Friday, March 20, 2020
Author Technique on ACT English Passage Strategy
Author Technique on ACT English Passage Strategy SAT / ACT Prep Online Guides and Tips Author technique is a specific type of reading comprehension question that appears frequently on the ACT English section. Author technique questions require you to analyze a specific sentence and determine if it fulfills an author's stated purpose. Read this article for a thorough explanation of author technique and guidance on how to figure out author technique questions. In this post, I'll do the following: Define author technique questions. Provide examples from real ACTs. Offer detailed strategies for correctly answering these questions. What Is Author Technique on ACT English? Author technique questions ask you to determine if a sentence or phrase fulfills the author's stated purpose. Each author technique question is constructed in the same way. Knowing the basic construction of author technique questions will allow you to easily identify them and use the same efficient process for correctly answering them. General Construction of Author Technique Questions Author technique questions are phrased in this way: Which one would best fulfill (some stated purpose)? A portion of a sentence will be underlined, and you have to determine if the given phrase or the other answer choices will best fulfill the purpose given in the question. This type of question requires you to analyze phrases and determine whether they would satisfy the stated goal. Now, let's look at examples of author technique questions from actual ACTs. Real Examples of Author Technique Questions Here are examples of author technique questions from the ACT English section. Example #1 By nightfall a controlled inferno roars in the kiln. The writer would like to indicate that at this point thefire is extremely intense. Given that all the choices aretrue, which one best accomplishes the writerââ¬â¢s goal? F. NO CHANGE G. the fire is stronger than everH. there is more heat being producedJ. a kind of intense blaze takes place Example #2 As the potter takes bricks away to create an opening into the oven, an expanding view of gleaming shapes rewards the artist for months of hard work. The writer would like to suggest the potterââ¬â¢s cautiouspace and sense of anticipation in opening the kiln. Given that all the choices are true, which one bestaccomplishes the writerââ¬â¢s goal? F. NO CHANGEG. removes bricks by handH. removes one brick at a timeJ. experiences great anticipation and removes bricks Example #3 Dickinson stayed in contact with correspondents for many years. Given that all of the choices are true, which one bestdevelops the paragraphââ¬â¢s focus on the roles that lettersplayed in Emily Dickinsonââ¬â¢s life? A. NO CHANGE B. Her personal interests also included keen observationof the natural world around her. C. Though she produced volumes of letters, none were shared publicly until after her death. D. She enjoyed hearing their news and reflecting with them on political events. Now, let's go through the process to correctly answer these questions. Follow these steps! Strategy for Author Technique Questions #1: Determine What the Question is Asking Here's our first example question again. Example #1 By nightfall a controlled inferno roars in the kiln. The writer would like to indicate that at this point thefire is extremely intense. Given that all the choices aretrue, which one best accomplishes the writerââ¬â¢s goal? F. NO CHANGE G. the fire is stronger than everH. there is more heat being producedJ. a kind of intense blaze takes place The question is asking which answer choice does the best job of indicating that the fire is extremely intense. The correct answer choice will make it obvious to the readerthat the fire is extremely intense. #2: Check the Answer Choices to See if They Acomplish the Intended Goal For our example, go through each answer choice and determine if it indicates that the fire is extremely intense. The answer choice has to match the goal as closely as possible. The fire canââ¬â¢t be somewhat intense. Weââ¬â¢re looking for extremely intense. First, look at the original sentence. Does ââ¬Å"a controlled inferno roarsâ⬠accomplish the goal of showing that the fire is extremely intense? Yes. An inferno is a large, intense fire. And the verb ââ¬Å"roarsâ⬠further indicates that the fire is extremely intense. However, go through the rest of the answer choices quickly just to make sure there isnââ¬â¢t a better answer. Answer choice G, ââ¬Å"the fire is stronger than ever,â⬠indicates that the fire is more intense than before, but it doesnââ¬â¢t directly state that the fire is extremely intense. Answer choice H, ââ¬Å"there is more heat being produced,â⬠does not even reference the intensity of the fire. Answer choice J, ââ¬Å"a kind of intense blaze takes place,â⬠is the trap answer. It has the word ââ¬Å"intenseâ⬠in the phrase, but weââ¬â¢re looking for a phrase that shows that the fire is extremely intense. A ââ¬Å"kind of intenseâ⬠fire is not extremely intense. #3: Eliminate Wrong Answer Choices Usually, itââ¬â¢s easier to eliminate the obviously wrong answer choices first before eventually arriving at the right answer. For our example, H could be eliminated right away since there isn't even a reference to the fire. Then, after looking more closely at the other answer choices, you should be able to eliminate G and J. #4: Consider the Tone and Conciseness of the Answer Choices Not only should the answer choice fulfill the purpose of the author, but the resulting sentence should be grammatically correct and match the essayââ¬â¢s tone. Typically, sentences in ACT English are moderately formal. Theyââ¬â¢re not extremely formal or very casual. Also, the ACT stresses that sentences should be as concise as possible. For our example, we didnââ¬â¢t really need to consider tone and conciseness, but if you were considering answer choice F, ââ¬Å"a kind of intense blaze takes placeâ⬠, itsconstructionmakes the phrase sound awkward and wordy. You could convey the same meaning more succinctly. #5: Select the Correct Answer In our example, we are left with answer choice F, NO CHANGE. Going through all of these steps should take roughly 15-30 seconds. We'll go through this process again with another question from a real ACT. Another Actual ACT English Example Try to figure out the answer to the following author technique question. At one point, Emily sent a draft of her poem ââ¬Å"Safe in TheirAlabaster Chambersâ⬠to Susan, who read the poem. Given that all the choices are true, which one wouldmost clearly describe an interaction between Susan andEmily during Emilyââ¬â¢s writing process? A. NO CHANGE B. liked the poem tremendously. C. considered and thought about the poem. D. praised the poem but suggested revisions. First, we determine what the question is asking. We need to choose a phrase that suggests interaction between Susan and Emily during Emilyââ¬â¢s writing process. Therefore, if a phrase doesnââ¬â¢t show interaction between the two, it can be eliminated. The original phrase, ââ¬Å"read the poem," doesn't show interaction. If Susan ââ¬Å"liked the poem tremendously," that doesn't show interaction between them either, so we can eliminate B. If Susan ââ¬Å"considered and thought about the poem," that doesn't demonstrate any interaction so answer choice C can be eliminated as well. However, if Susan ââ¬Å"praised the poem but suggested revisionsâ⬠, that does describe an interaction during the writing process. If she ââ¬Å"suggested revisions,â⬠Susan told Emily how to change the poem to make it better. That's an interaction during the writing process. The answer is D. Quick Review of General Strategies for Author Technique Questions #1: Determine What the Question Is Asking #2: Go Through the Answer Choices to See if the Phrase Fulfills the Stated Purpose #3: Eliminate Wrong Answer Choices #4: Consider the Conciseness, Tone, and Formality of Answer Choices, if Need Be. What's Next? If you haven't done so already, I strongly suggest that you check out these articles on the best way to approach ACT English passages and five critical concepts to ace ACT English. Both posts provide you with extremely helpful strategies that will allow you to maximize your ACT English score. For those of you looking to improve your ACT English grammar skills, you may want to read up on punctuation on the ACT. Want to improve your ACT score by 4 points? Check out our best-in-class online ACT prep program. We guarantee your money back if you don't improve your ACT score by 4 points or more. Our program is entirely online, and it customizes what you study to your strengths and weaknesses. If you liked this English lesson, you'll love our program.Along with more detailed lessons, you'll get thousands ofpractice problems organized by individual skills so you learn most effectively. We'll also give you a step-by-step program to follow so you'll never be confused about what to study next. Check out our 5-day free trial:
Tuesday, March 3, 2020
Statement of purpose essay
Statement of purpose essay Statement of purpose essay A statement of purpose essay is exactly what it claims to be-a statement of your purpose in life. What is it that you want to achieve by choosing a particular course or college? And how will this help you to fulfill your purpose? Before starting to write a statement of purpose essay it is essential for you to do some soul searching. What kind of a person are you? Are you driven by a strong drive to help the poor and needy? Then this would be an adequate reason for looking for admission in to a social work course. Also, you can read:http://.com/blog/law-school-personal-statement Short is sweet The golden rule is that if you can say it in six words, dont use twenty. Ensure that what you say is relevant and interesting. If it is not-dont say it-this is one time when silence really proves golden. Tips for success Write on an aspect of life that you have knowledge and interest in. Enjoyment while writing ensures reading enjoyment. If you are a practical down to earth person-use your power of observation to reinforce your central point. If you are more bent towards the why of things then look at the esoteric aspects Make your writing style unique and gripping. Do not repeat points or incidents as this can bore the reader who will quickly loose interest Illustrate your statement of purpose essaywith your past experience and achievements that have left you better equipped to fulfill your goal in life. Examine how future plans and long term goals will get realized if you are given a chance in your chosen college. Motivate the admissions committee to read through your statement of purpose essayby weaving a human interest story around it. Mention specific incidents in which you made a difference. Do not just list your qualities without narrating what helped you to discover your purpose in life. Ensure that your statement of purpose essay has a proper structure with the introductory paragraph stating your purpose and following paragraphs highlighting the logical steps you undertook to reaffirm your purpose. The concluding paragraph should leave the admissions committee feeling that you are the logical choice for admission. Ensure that your statement of purpose essay sounds enthusiastic and positive. Do this by zeroing in on your winning qualities and playing down your negative points. Additional topics: Informative Essay Writing Drama Coursework Help Media Studies Coursework Case Study Analysis Critical Thinking Essay
Sunday, February 16, 2020
Mandatory Recycling in the USA Essay Example | Topics and Well Written Essays - 1000 words
Mandatory Recycling in the USA - Essay Example Air pollution that coming from the process of burning fossil fuels is one of the common factors that causes acid rain. (U.S. Geological Survey and U.S. Environmental Protection Agency, 1999) In other words, electric utility plants are among the major sources of emitted sulfur dioxide and nitrogen oxide that are present in the atmostphere. As explained by Science, global warming and the nitrogen oxide present in the acid rain could cause negative impact on the environment aside from declining the annual crop yields due to the presence of flood caused by typhoon and/or prolonged hot season that often leads to the growth of new pesticides and fungicides. (Hampton, 2008; Union of Concerned Scientists, 2006) For this reason, income from agricultural activities becomes lesser. On the other hand, the thinning of the ozone layer could cause human beings to suffer from skin cancer and other related health detriments. (The Daily Galaxy, 2007) Aside from causing serious damage on agricultural products, acid rain could also severely damage our natural sources of water such as lakes and streams. (U.S. Geological Survey and U.S. Environmental Protection Agency, 1999) Given the fact that trees absorb water from the ground, there is a higher chance that trees and other plants would die caused by high amount of acid found in the ocean, lakes, streams, rivers, and water reservoir. For this reason, forest degradation is most likely to occur.
Sunday, February 2, 2020
Professional Accountability Discussion Paper (nursing) Essay
Professional Accountability Discussion Paper (nursing) - Essay Example This discussion is about the professional accountability of persons engaged in the medical profession. Due to the advancements in the medical technology, today doctors are able to offer treatments that cure even the very complicated conditions. People with potentially life threatening conditions are able to prolong their lives due to the remarkable improvements in the treatments. But here doctors are faced with an important issue of explaining to the patient the kind of treatment to be administered, the possible results, side effects that may occur and get the consent of the patient. Obtaining the consent of the patient is very essential to commence any kind of treatment. Patient autonomy which means the right of the patient who is in a sound mental capacity to take the decision whether to acceptor refuse the treatment is given utmost importance. If the patient is not in a state of mind to give his consent, efforts should be made to find out the views expressed by him earlier in this regard or the consent of the closest family member should be obtained. When neither could be done, that situation put doctors in a fix. They land in an ethical dilemma as to whether to save the life of the patient or to respect his own decision even if it would lead him to his end of life. The following problem deals with such a kind. You are working in a casualty department of a large hospital. An accident victim is rushed in one evening. He is conscious, but badly injured and desperately in need a blood transfusion. However, he turns out to have religious principles that forbid the exchange of blood. You explain the situation to him, including the very really threat to his survival if he does not have a transfusion. He clearly understands exactly what you are telling him, but still refuses to accept a transfusion, and asks you to do what you can by other means. He
Saturday, January 25, 2020
Realism And Naturalism In The Literary World English Literature Essay
Realism And Naturalism In The Literary World English Literature Essay When people think of what is real, that often think of what is natural. When people think of what is natural, they often think of something real. However, these statements do not apply to literature. Although Realism and Naturalism seem as if they should be the same exact concepts, they have completely different meanings in the literary world. The movement towards Realism began after the Romanticism period when people became more interested in stories that could relate to their everyday lives. From there, Naturalism was invented. Realism is writing about something that is real, or possible. It has everyday people, ordinary scenarios, and familiar language to that culture. Although Naturalism captures some of the same ideas, it is often much darker and filled with a more Gothic feel of literary devices. The Death of Ivan Ilyich is a great example of a literary work from the Realism era. A work that describes the later movement to Naturalism is The Lost Phoebe. By contrasting these two examples, I believe you can identify the differences between Realism and Naturalism. The Death of Ivan Ilyich is the story of a man who has worked his way into a high social standing, married a good wife, and started what seems to be the perfect family. When a fatal illness takes over, Ivan starts to see himself change not only physically, but mentally as well. This story is a piece from the Realism movement. All the characters are living normal, ordinary lives. What seems to be the perfect family to outsiders is not so perfect on the inside. Everything that revolves around this piece could be true, or real, for other families. It was created to make a social change, often a principle of Realism. The idea was to use their own methods to reveal the cruelty of the society that many people, like Ivan Ilyich, take such pride in. In the beginning of the story, Mr. Ilyichs coworkers are all discussing his death and the effects that his death could cause. He had been ill for some weeks with an illness said to be incurable. His post had been kept open for him, but there had been conjectures that in case of his death Alexeev might receive his appointment, and that either Vinnikov or Shtabel would succeed Alexeev. The people that he spent most of his time with in a single day did not care about the fact he was ill or hurting in pain. The only thing that came to mind is how they could better themselves. This is a problem that we see in society from the past and now; it is a real idea yet told in a fiction setting. Another sad but true, realistic idea that is discussed in the story is marriage and love. Ivan Ilyich did not marry his wife for love. Several people tend to not marry for this reason and find other comfort areas like finance and success. To say that Ivan Ilyich married because he fell in love with Praskovya Fedorovna and found that she sympathized with his views of life would be as incorrect as to say that he married because his social circle approved of the match. Another point of view this story steps on is selfishness. Ivan had tried to give his only daughter the best possible life, even if it meant not being home most of the nights. When he becomes ill, she has no way to show love for her father because of the other things that are more important in her life. Their daughter came in in full evening dress, her fresh young flesh exposed, strong, healthy, evidently in love, and impatient with illness, suffering, and death, because they interfered with her happiness. Its hard to think from my own point of view how someone could act in such a way towards their own family; the Realism of this story is that scenarios like this happen everyday. Someone can pinpoint how the struggles in this mans life could be similar to what someone else is going through and how it could also correct us in the way that we live our own. The major point of view revolves around his life and the decisions he made on how to live. It was his choice and when death came upon him, he could decide if he made the right ones. In the story of The Lost Phoebe, an elderly man and his wife live together with the little money they have and they little food they can put on the table. Even though circumstances are not the best, happiness seems to come from just them being together. In the period of Naturalism, many of the ideas were focused around characters of a lower rank in life. It believed that life is deterministic; man is not a free agent, but he is an animal motivated by his chemistry, heredity, and environment of circumstances. Henry, the old man, seemed to find motivation in the love for his wife Phoebe. The ideas of this literary work still speculate around realism including original language of ordinary characters, but in this work, it seems to be a darker story with a semi-twisted happy ending. Henry had been married to the love of his life for 48 years. Old Henry and his wife Phoebe were as fond of each other as it is possible for two old people to be who have nothing else in this life to be fond o f. Henry always accused his dear wife of misplacing his belongings even though they most likely had no importance at all; other than that, their lives together were peaceful and sympathetic. Phoebe, Wheres my corn-knife? You aint never minded to let my things alone no more. Now you hush, Henry. If you dont, Ill leave yuh. Ill git up and walk out of here someday, and then where would y be? Y aint got anybody but me to look after yuh, so yuh just behave yourself. His wife always knew how to calm him and take control of the situation. Not long afterwards, Henrys wife passed away. Im sure he felt almost as if the whole world around him had fallen apart. He had not order to his life and the only thing that kept him motivated was Phoebe. Up into this part of the story, everything can relate to Realism. On the night that Henry spots the bright light of the moon, he takes a turn toward the unknown and becomes eager to fins his long lost Phoebe. Henry somehow took a illness that destroyed th e memory of his wifes death. He finally makes the decision to set out and search for her. He remembered her threat had always been, Yuhll not find me it I ever leave yuh. I guess I kin git some place where yuh cant find me. Henrys desperate attempt to find Phoebe lasted for seven long years going door to door and looking under every rock and in every hole until it eventually came to an end. Of a sudden there came to him now for the first time in many years the full charm of her girlish figure as he had known it in boyhood, the pleasing, sympathetic smile, the brown hair, the blue sash she had once worn about her waist at a picnic, her gay, graceful movements. He walked around the base of the tree, straining with his eyes, forgetting for once his cane and utensils, and following eagerly after. He thought he had finally found his one true love, Phoebe. In desperation to follow her and finally get her to come back home, Henry jumps to his death and to his Phoebe. You could think of thi s story with a tragic ending; a man who jumped off a cliff chasing after nothing but a dark shadow in the middle of the night. I think of this story as a love story; a man who had searched for his long lost love for seven straight years and he finally found her, through death. This work includes several of the same ideas of that of Realism; however, the main theories behind both of them differ completely. The Lost Phoebe includes many Romantic, Gothic ideations with a sense of Realism; the idea that creates Naturalism. In The Death of Ivan Ilyich, the author is reaching out through a real life scenario to make a change within a community and within peoples lives, a principle of Realism. It includes ordinary characters, familiar language, and a realistic point of view. In The Lost Phoebe, the meaning is much deeper. A man in search for his true love, but in all actuality, he never finds her. They learned to live in peace with the lesser things in life. Naturalism incorporated the same ideas as Realism just in a deeper and darker way.
Friday, January 17, 2020
MRI Applications Imaging Knee Joint Health And Social Care Essay
The articulatio genus articulation is one of the most complicated articulations in the human organic structure. Because the articulatio genus is so vulnerable in many respects, it is besides the most normally injured articulation, particularly in the younger, athletic population. As a consequence of the enormous emphasiss applied on the constructions of the articulatio genus during athletic activities, articulatio genus hurts are besides the taking cause of long-run disablement of jocks ( Davies & A ; Cassar-Pullicino 2002 ) . In add-on to other imaging modes such as computing machine imaging, ultrasound and general skiagraphy, magnetic resonance imagination ( MRI ) is now normally used to picture the complex anatomy and pathological findings of one of the most of import joint articulations in our organic structures ( Harper et al 2005 ) . The cause of internal mental unsoundnesss of the articulatio genus can run from athleticss activities to effects of devolution. Arthroscopy was the primary method used to accomplish a comprehensive rating of articulatio genus joint constructions before MRI became widely available. In comparing to MRI imagination, the arthroscopic process is both invasive and expensive. With the outgrowth of MRI as a powerful diagnostic tool, arthroscopies are no longer routinely used to name internal articulation constructions. Alternatively, it is now more normally used for curative benefits, and to clear up inconclusive findings ( Grenier et al 2004 ) . MRI has contributed mostly to the basic apprehension and clinical diagnosing of assorted hurts and conditions impacting the articulatio genus. The different constructions in the articulatio genus can be visualized in great item on different MRI pulsation sequences.MeniscusThe semilunar cartilage are made up of fibrocartilaginous constructions that a ttach to the condylar surface of the shinbone. The median semilunar cartilage remainders on the interior of the articulatio genus, whilst the sidelong semilunar cartilage lies on the exterior of the articulatio genus. Meniscal hurts are one of the most common causes of articulatio genus hurting and disablement ( Alatakis & A ; Naidoo 2009 ) . Acute meniscal hurts are normally caused by either valgus emphasis with external rotary motion or varus emphasis with internal rotary motion of the articulatio genus. Patients with meniscal harm normally experience hurting and swelling as their primary symptoms. Other common ailments include joint-locking, starting and snaping within the articulatio genus, or the inability to wholly unbend the articulation. Harmonizing to Feller ( 2002 ) , additive, complex, or diffuse increased signal strength within the semilunar cartilage and communicate with an articular surface are declarative of meniscal cryings on MR images. Meniscal cryings may be descr ibed in assorted ways, which include horizontal cleavage, radial, parrot beak, peripheral or perpendicular, flap, bucket-handle, meniscocapsular separation, complex, and macerated ( Feller 2002 ) . Grenier ( 2004 ) describes the normal semilunar cartilage as a semi-circle of gristle and collagen fibers that appear as low, homogeneous signals with wedged-shape profiles on all MRI sequences, and ââ¬Ëbow-tie ââ¬Ë profiles on sagittal pieces ( Figure 1 ) . Younger patients may look to hold intrasubstance signal around the peripheral border on the scans. This happening is sometimes mistaken for a tear. However, the signal is more frequently showing vascularity, non pathology. Although the axial plane can be used to expose meniscal construction, everyday axial images at 4 to 5mm may be excessively thick to show meniscal pathology. Harmonizing to Fox ( 2007 ) , a piece thickness of about 3 to 4 millimeter is more ideal in showing a meniscal tear in the axial plane. The anterior and posterior horns of the median and sidelong semilunar cartilages are best demonstrated on sagittal pieces, whilst coronal images best show the meniscal organic structures. Hence, the semilunar cartilage are best evaluated on the sagittal and coronal planes. High spacial declaration and an optimized signal/noise ratio ratio are besides required to supply accurate visual image of the semilunar cartilage. At our pattern, PD- weighted fast spin-echo images are preferred for meniscal rating as they can show the assorted classs of meniscal cryings or devolution. Meniscal hurts are frequently accompanied by secondary pathologies of the articulatio genus. Fat impregnation is besides appli ed in the PD sequences to visualise any presence of ligamentous hurts and bone marrow hydrops ( Harper et al 2005 ) . Figure 1. T1-weighted sagittal image of the right articulatio genus showing the normal ââ¬Ëbowtie ââ¬Ë visual aspect of the sidelong semilunar cartilage ( Grenier et al 2004 ) . Meniscal cysts can frequently do marks and symptoms consistent with typical meniscal pathology, and include swelling, hurting, tenderness, limited mobility, and a tangible mass. They are normally unstable aggregations that have resulted from the peripheral borders of horizontal cleavage cryings or complex cryings of the semilunar cartilage. Meniscal cysts besides tend to be more normally associated with cryings in the sidelong semilunar cartilage, and are by and large accompanied by lateralizing joint line tenderness ( Feller 2002 ) . Harmonizing to Grenier & A ; Wessely ( 2004 ) , the cystic mass normally appears with low signal strength on T1-weighted images, but has increased signal strength on T2-weighted MR images. Meniscal cysts can look in all imagination planes, but are best demonstrated in axial and coronal images.Ligaments: Cruciate & A ; CollateralLigamentous hurts of the articulatio genus are common happenings among jocks. The constructions that function as the chief stab ilizers of the normal articulatio genus joint consist of four chief ligaments ; the medial and sidelong collateral ligaments, every bit good as the anterior cruciate ligament ( ACL ) and posterior cruciate ligament ( PCL ) ( Tham et al 2008 ) . The most often injured ligament in the articulatio genus is the anterior cruciate ligament ( ACL ) . The ACL ââ¬Ës primary maps are to forestall anterior interlingual rendition of the tibia relation to the thighbone, limit rotary motion of the shinbone when the articulatio genus is in extension, and bound varus and valgus emphasis when the medial and sidelong collateral ligaments are injured. Cryings of the ACL are normally caused by valgus emphasis or hyperextension, and normally occur in featuring activities that involve changeless acceleration and slowing ( Berquist 2001 ) . Although best demonstrated in the sagittal position, the normal ACL appears as a thick set of fibers with low signal strength on all imaging planes. The ACL is best demonstrated in the sagittal plane. In the normal articulatio genus, it is shown to attach proximally at the internal facet of the sidelong femoral condyle, and distally to the anterior shinbone and the anterior facet of the tibial spinal column ( see Figure 2a ) . However, due to partial averaging of the proximal ACL with the cortical border of the sidelong femoral condyle, the proximal femoral fond regard of the ACL is non ever demonstrated faithfully on sagittal images. Therefore, axial images can be helpful in visualising the proximal ACL and femoral fond regard. On the coronal pieces, the ACL is demonstrated as a level set adjacent to the sidelong femoral condyles ( Grenier et al 2004 ) . If there is no visual image or discontinuity of the ACL in merely the sagittal plane, it is normally sufficient in naming the presence of an ACL tear. When there is a tear nowadays, the ACL fibers can be seen to be wholly or partly disrupted with unnatural morphology and signal strength ( Tham et al 2008 ) . Other marks of a tear are discontinuity and an change of the orientation of the fibers ( see Figure 2b ) . Harmonizing to Grenier & A ; Wessely ( 2004 ) , intrasubstance high signal countries tend to be indexs of partial cryings in the ACL. Chronic cryings are characterized with outstanding fibrosis and associated cicatrix formation. Because of the mechanism of hurt, ACL cryings are frequently accompanied by associated ligamental, meniscal, and boney hurts. Figure 2a ) ( left ) Sagittal proton-density image of the articulatio genus demoing the normal ACL ( white pointer ) ( Tham et al 2008 ) . B ) ( right ) Sagittal T1-weighted image of the articulatio genus demoing discontinuity of the ligament fibers ( pointer ) , proposing an acute tear in the ACL ( Grenier et al 2004 ) . The chief map of the posterior cruciate ligament ( PCL ) is to move as the primary stabilizer of the articulatio genus, and prevent posterior interlingual rendition of the shinbone. It is located near the centre of rotary motion of the articulatio genus, and has a normal ââ¬Ëinverted hockey-stick ââ¬Ë visual aspect. Because the PCL is thicker and stronger than the ACL, it is injured less normally. However, hurts to the PCL can be caused by a direct blunt force to the anterior facet of the articulatio genus. The force of the injury can force the shinbone back posteriorly in relation to the thighbone, ensuing in a sprain or tear of the PCL ( Roberts et al 2007 ) . Injuries to the PCL can show the same scope of visual aspects on MR imaging as ACL hurts, including focal countries of unnatural signal to finish break of the ligament. Specific countries of increased signal strength and break of ââ¬Ëhockey-stick ââ¬Ë visual aspect of the PCL are common indexs of a partial tear of the PCL ( Figures 3 a & A ; B ) . However, PCL cryings are non every bit common as ACL cryings, and secondary findings may non be as characteristic or well-described. The PCL is visualized in all MRI planes and sequences with a uniform, hypointense signal. Similar to the ACL, the PCL is besides best visualized on sagittal images, and can hold partial or complete cryings ( Grenier & A ; Wessely 2004 ) . Coronal images may be helpful in measuring the short diameter cross-section of the PCL ( Davies & A ; Cassar-Pullicino 2002 ) . Figure 3a ) ( left ) The upside-down ââ¬Ëhockey stick ââ¬Ë visual aspect of the PCL is shown in a sagittal T1-weighted image of a normal articulatio genus. B ) ( right ) The signal strength of the PCL has changed, and there is besides discontinuity of the fibers. The PCL no longer has an ââ¬Ëinverted hockey-stick ââ¬Ë visual aspect ( Grenier et al 2004 ) . The chief constructions that provide stableness to the medial and sidelong parts of the articulatio genus are the indirect ligaments. MRI rating of the collateral ligaments is effectual, but can be disputing because of the anatomic fluctuation and the thin nature of these constructions. The mechanisms of hurt to the medial and sidelong collateral ligaments are inordinate valgus and varus emphasis ( Helms et al 2009 ) . The median collateral ligament ( MCL ) is normally visualized as a level construction that begins from the epicondyles of the thighbone and attaches into the median shinbone. The MCL is the 2nd most normally injured ligament in the articulatio genus. The sidelong or fibular collateral ligament ( LCL ) attaches the distal thighbone to the fibular caput collectively with the biceps femur, and is the chief restraint to varus forces on the articulatio genus ( Grenier et al 2004 ) . The collateral ligaments are by and large best visualized on coronal pieces, looking as countries of low signal strength ( see Figures 4 a & A ; B ) . The LCL can by and large be evaluated on a individual coronal image due to its oblique class. The short diameter cross-section of the MCL can besides be demonstrated on consecutive axial images. These are indispensable in finding the extent of partial cryings or intrasubstance sprains ( Davies & A ; Cassar-Pullicino 2002 ) . When there is a complete tear of the LCL, irregular contouring of the lacerate ligament with environing fluid or hydrops can be observed on MRI images ( Feller 2002 ) . As with the semilunar cartilage, conventional spin reverberation sequences provide moderately accurate appraisal of the ligaments. The normal ligament may be good visualized on T1-weighted spin-echo images. But in the presence of a joint gush, the unity of the cruciate ligaments may be hard to measure. In our pattern, PD spin-echo sequences are by and large used in all imaging programs as they provide good contrast between the ligament and joint fluid, and show a greater SNR ( Davies & A ; Cassar-Pullicino 2002 ) . Figure 4a ) ( left ) Coronal PD images of the articulatio genus show a normal sidelong collateral ligament ( LCL ) that attaches from the sidelong femoral condyle to the caput of the calf bone ( white arrowheads ) . B ) ( right ) The normal median collateral ligament ( MCL ) can be seen attaching from the median femoral condyle to the median surface of the organic structure of the shinbone ( white pointers ) ( Tham at el 2008 ) .Osseous PathologyBone bruising is frequently associated with coincident soft tissue hurts. Therefore, placing bone bruising besides helps to place other possible hurts. Tension injuries affecting ligaments tend to avulse bony fond regard sites. Bone bruising at the sidelong femoral condyles and the posterolateral facet of the tibial tableland are normally related to acute cryings of the ACL. Assorted hurts to the ligamentous and meniscal constructions are besides associated with osteal pathology. Although blunt breaks can be good visualized on conventional sk iagraphy, bone bruising by and large requires MRI to be visualized ( Grenier & A ; Wessely 2004 ) . Traumatic bony lesions, microfractures or trabeculate hurts that occur in the ague or subacute scene are normally accompanied by bone marrow hydrops. They by and large present as low signal strength countries on T1 images, or increased signal strength countries on T2 and fat suppressed images. Fat suppressed images are helpful as they will show an increased signal strength if bony jobs are present. Fat suppression eliminates the signal from the marrow, therefore leting bone marrow hydrops to go more apparent. Figure 5 demonstrates an country of increased signal strength on a T2-weighted image, bespeaking the presence of bone bruising. Bone bruises and stress reactions can frequently look as a diffuse or localised country of low signal strength on T1- weighted images. A defined break line is normally non seen. However, any cortical or stress breaks that may be present would look as cri sp, chiseled, additive subdivisions with reduced signal strength on all MR sequences ( Feller 2002 ) . Figure 5. Sagittal T2-weighted image showing a big bone bruise within the femoral condyle ( pointer ) ( Grenier & A ; Wessely 2004 ) .Extensor muscle MechanismThe extensor mechanism is made up of the quadriceps musculus and sinew, kneecap, and patellar sinew. Injury to the extensor mechanism seldom occurs. However, should it happen, it is normally indirect, and is frequently caused by strong quadriceps contraction that is opposed by forced flexure of the articulatio genus. Loss of map in the extensor mechanism and sever hurting are direct consequences of complete break of the mechanism ( Feller 2002 ) . Patellar disruption occurs when the kneecap has been wholly displaced from the femoral trochlea, and is the most common cause of break of the extensor mechanism. The disruption about ever occurs to the sidelong side. An arthroscopic process is normally required if a piece of patellar gristle is found on the MR images ( Stoller 2002 ) . Osgood-Schlatter disease and jumperA?s articulatio genus both root from chronic patellar tendinitis. With Osgood-Schlatter disease, redness of the sinew occurs. However, with jumper ââ¬Ës articulatio genus, micro-tears and collagen devolution occur as a consequence of puting repeated strain on the joint with gestures such as leaping motions ( Berquist 2001 ) . Both entities have similar MRI findings, and are demonstrated as focal or spindle-shaped thickener of the patellar sinew, and may show with increased intratendonous signal. The increased signal by and large appears near the tibial tubercle with Osgood-Schlatter disease. However, with jumperA?s articulatio genus, the increased signal is normally present near to the part of the inferior pole of the kneecap. Overliing hypodermic hydrops can sometimes happen, taking to countries of low signal strength due to bony fragments ( Feller 2002 ) .Extra InjuriesInjury to the articulatio genus can besides ensue in hurt to other of import soft tissue constructions, such as the Bursa, which includes the popliteal, prepatellar, pes anserinus, semi-membranosus and tibial collateral ligament Bursa. Inflammation, or bursitis, in these countries can frequently be mistaken for other intra-articular pathologies. MRI is able to supply brilliant visual image of these soft tissue constructions. The popliteal Bursa is normally the most common site of hurt. The normal popliteal Bursa may incorporate a little sum of fluid in the posterior facet of the articulatio genus, and by and large nowadayss as a focal country of increased T2 signal ( Grenier et al 2004 ) . Traumatic haemarthrosis can besides happen as a consequence of a meniscal or ligamental tear. MRI imagination is helpful in finding the beginning of the hydrops. A standard articulatio genus protocol is normally sufficient in imaging traumatic haemarthrosis.MR ArthrographyConventional arthrography has bit by bit become unneeded with the debut of MRI of the articulatio gen us. MR arthrography is used merely when there is a demand to foster measure the post-operative meniscua, osteochondral lesions, or show loose organic structures, in a patient with no joint gush. MR arthrography may be direct or indirect ( Helms et al 2009 ) . In indirect arthrography, Gd is injected intravenously. The articulatio genus is so scanned about 10 to 20 proceedingss after, during which some contrast would hold diffused into the articulatio genus articulation. However, indirect arthrography does non supply distention of the articulatio genus articulation with fluid, which is indispensable in this process. Hence, indirect arthrography remains more limited. With direct arthrography, contrast is injected straight into the patellofemoral articulation through the sidelong facet of the kneecap. If the radiotherapist executing the process is experienced, fluoroscopic counsel is non even necessary. MR arthrography of the articulatio genus is non presently performed at our pattern, and at the minute, no protocol has been established for this process. However, harmonizing to Magee et Al ( 2003 ) , T1-weighted images with fat impregnation are typically employed following the injection of Gd. If normal saline is used as the contrast agent, T2-weighted or gradient echo images with T2 weighting may be used every bit good.MR ProtocolWith our 1.5-Tesla MR system, imagination of the articulatio genus is performed with the patient in a supine place, with a dedicated phased-array quadrature articulatio genus spiral. If the patient ââ¬Ës articulatio genus is unable to suit into the standard spiral, or that the patient has trouble widening their articulatio genus, a flexible surface spiral may be used. Most patterns have standard protocols for MR imaging rating of the articulatio genus which normally includes coronal, sagittal, and axial positions. A standard articulatio genus protocol at our pattern includes: T1 Sagittal PD FS Sagittal ( Proton denseness with fat impregnation ) T2 GRE ( Gradient echo ) Sagittal PD Coronal PD FS Coronal PD FS Axial Sagittal images are likely the best imagination plane at showing pathologies affecting the internal constructions and assorted pathologies of the articulatio genus. Components of the median and indirect ligaments, every bit good as the next capsule, are well-demonstrated in the sagittal plane. Mid-sagittal pieces can supply visual image of the patellofemoral compartment, quadriceps, and kneecap sinew. The ACL and PCL are besides best displayed on sagittal images. The sagittal plane is normally sufficient in naming cryings of the ACL and PCL, as breaks or unnatural signal strengths bespeaking a tear are easy demonstrated in the sagittal plane ( Davies & A ; Cassar-Pullicino 2002 ) . Images in the sagittal plane can besides be highly helpful in measuring meniscal anatomy for both devolutions and cryings. The coronal plane enables the visual image of the posterior capsule, popliteus sinew, cruciate ligaments and semilunar cartilage, the collateral ligaments, and the extensor mechanism. The collateral ligaments are besides often evaluated utilizing the coronal plane. Coronal images can be used in concurrence with sagittal images to show the cruciate ligaments, and to measure the posterior femoral condyles, which are common sites of articular eroding. The low signal strength popliteal vass are besides identified on posterior coronal images ( Helms et al 2009 ) . Due to the oblique orientation of the median and sidelong patellar aspects, every bit good as the articular gristle, the axial plane is the most equal at showing these constructions through the patella-femoral articulation. Axial plane images by and large serve as a localizer to find sagittal and coronal planning. Majority of the osteal dealingss between the kneecap, thighbone and tibua, every bit good as the fond regards of the cruciate and indirect ligaments can be displayed in axial images. The larger sidelong patellar aspect and the oblique median kneecap aspect are besides seen in the axial plane, as are both the sidelong and median patellar retinacular fond regards at the degree of the patellofemoral articulation ( Davies & A ; Cassar-Pullicino 2002 ) . In order to adequately measure the articulatio genus, images should be obtain in the sagittal, coronal and axial planes. All three imaging planes work in concurrence to show all the internal constructions of the articulatio genus. For illustration, although the semilunar cartilage are chiefly evaluated on sagittal images, they are frequently supplemented by images in the coronal plane. Sagittal images are used to visualise the cruciate ligaments, which can besides be farther assessed on coronal and sometimes axial images. Coronal images are indispensable in showing collateral ligaments, but are besides supplemented by axial images. The patellofemoral articulation is best assessed on axial images, but can besides be evaluated on sagittal images ( Stoller 2002 ) . Hence, all three planes are indispensable in exhaustively showing the articulatio genus. The most normally used sequences for MRI of the articulatio genus include spin-echo or fast spin-echo ( FSE ) proton denseness sequences , with or without fat impregnation, T1 and gradient reverberation ( GRE ) .Image SequencesStandard protocols for MRI rating of the articulatio genus include sagittal, axial and coronal images. A typical modus operandi protocol at our pattern may include sequences such as: PD- leaden spin-echo imagination ; T1-weighted spin-echo imagination ; and T2-weighted gradient reverberation imagination. Other optional protocols include a short tau inversion recovery ( STIR ) sequence in the sagittal plane. In PD-weighted sequences, the image contrast is dependent chiefly on the denseness of protons in the imagination volume. The images are typically acquired utilizing TR that is greater that with T1 sequences, and TE that is less than in T2 sequences. At our pattern, PD sequences are chiefly used in all planes to show the articulatio genus. This is because PD spin reverberation images have high signal to resound ratio, and are able to supply accurate anatomical item. When fat impregnation is applied, PD-weighted sequences have an increased sensitiveness for synovial fluid within meniscal cryings. This makes the sequence highly valuable in measuring meniscal pathology. The combination of fat impregnation with PD weighted sequences besides allows for high sensitiveness to cartilage and intramedullary osteal abnormalcies ( Stoller 2002 ) . Fat impregnation to supply a better presentation of any abnormalcy, appraisal of bone marrow abnormalcies, and enables the distinction between fluid an d fat at their interface. Fat impregnation is applied to take the high signal strength of fat in the articulatio genus, therefore leting bone marrow pathology, semilunar cartilage and gristle to be demonstrated more clearly. Therefore, PD weighted sequences with fat impregnation is used in all three imaging planes to measure the articulatio genus ( Davies & A ; Cassar-Pullicino 2002 ) . However, PD weighted sequences utilizing fat impregnation normally require longer scanning times, which can sometimes be a disadvantage to the injured patient. The effectivity of fat impregnation is besides decreased at low magnetic field strengths, and it is extremely sensitive to local magnetic field inhomogeneities ( Helms et al 2009 ) . A gradient reverberation sequence and T1-weighted sequence are besides performed in the sagittal plane. In imagination, a T1 image is obtained when merely one reverberation is generated utilizing a short TR and TE. The T1-weighted sequence provides a general overview of the anatomy and any gross pathology. Normal anatomy of the ligaments and semilunar cartilages can be adequately visualized on T1 images. However, in the presence of a joint gush, any pathology nowadays may go hard to measure. T1-weighted images are besides non able to adequately show the hyaline gristle as it appears of low signal strength, and is hence identical from joint fluid ( Stoller 2002 ) . A gradient reverberation is formed when a brace of bipolar gradient pulsations is used. In T2-weighted gradient reverberation sequences, a smaller somersault angle is used, along with longer TR and TE. Signal strength alterations within the ligaments ensuing from hurt are more clearly demonstrated on T2-weight gradient reverberation sequences, therefore leting for the accurate appraisal of the unity of the ligament. Gradient reverberation images besides display the hyaline gristle with high signal strength, which in bend contrasts aggressively with next constructions of low signal strength ( Davies & A ; Cassar-Pullicino 2002 ) . However, because gradient reverberation images do non supply equal visual image of bone marrow pathology, they are non by and large recommended for the rating of bony pathology, particularly in the instance of the injured patient.DiscussionStandard articulatio genus imaging protocols can besides include T2-weighted every bit good as STIR sequences. Conventio nal PD sequences were compared to FSE-PD sequences in 216 back-to-back surveies. Amongst the 216 patients, it was found that 42 cryings were missed on the fast spin reverberation ( FSE ) PD sequences, but shown in the conventional PD sequence ( Helms 2009 ) . Hence, Helms et Al ( 2009 ) concludes that FSE PD images are unacceptable in the imagination of the articulatio genus. Alternatively, the writer suggests that sagittal FSE T2-weighted images with fat impregnation would supply brilliant visual image of the cruciate ligaments, gristle and osteal constructions. Similarly, the survey states that although gradient reverberation sequences would do for imaging the gristle, but was unacceptable of showing the castanetss. However, a separate survey by Wolff et Al ( 2008 ) has found that FSE PD-weighted sequences are sufficient in showing meniscal cryings. T2-weighted and STIR sequences are non typically performed at our pattern. T2-weighted fast spin-echo MR imagination with fat impregnation can be an accurate and fast technique for observing and rating articular gristle defects in the articulatio genus ( Alatakis & A ; Naidoo 2009 ) . Because PD-weighted sequences have high SNR and can supply high anatomic item, we chiefly use PD sequences in geting articulatio genus images. However, it has been noted that pathology, which is characterized by an addition in unstable content, can be accentuated in the PD weighted sequences. One of the benefits of the STIR sequence is that the signal from fat is wholly suppressed. Another advantage of the STIR sequences is that because they are based on the rapid T1 recovery of fat, they can be employed utilizing low field strength, and are non affected by gradient field inhomogeneities. Because the STIR sequence does non trust as much on the homogeneousness of the magnetic field, it can supply an alte rnate method of fat signal suppression. Bone hydrops can besides be assessed utilizing STIR sequences. However, STIR images by and large have a comparatively low SNR. Thus, tissues with a similar T1 to flesh out, such as bleeding, melanin and Gd, may besides be suppressed ( Berquist 2001 ) . For this ground, STIR sequences are by and large unsuitable for MR arthrography or scanning following endovenous Gd ( Magee et al 2003 ) . This sequence may be used in our pattern if there is metal artifact nowadays. Metallic devices can make an inhomogenous magnetic field. This can ensue in countries of suboptimal fat impregnation. STIR sequences frequently result in reduced SNR, and as a consequence, images can hold a farinaceous visual aspect with loss of tissue signal declaration ( Helms et al 2009 ) . STIR sequences besides require longer scan times. After reexamining the literature, it has been taken into history that some alterations to our current protocol could be made. It is my continued belief that the PD-weighted sequences utilizing fat impregnation provides that most accurate information sing the constructions of the articulatio genus articulation. However, some consideration is necessary in respects to the add-on of T2 fat-saturated wreath and sagittal sequences may be necessary so as to visualise pathology such as recurrent cryings, perchance replacing the demand for a T1-weighted sagittal sequence. A possible alteration of protocol may include FSE T2-weighted images with fat impregnation in all three planes. A conventional PD-weighted sequence with fat impregnation in the sagittal plane should be included, therefore supplying high truth of the semilunar cartilage, ligaments and gristle ( Helms 2009 ) . STIR sequences may be used to replace gradient reverberation sequences if there is metal present, or if rating of the bone marrow is required. When make up one's minding whether or non to alter the sequences, one must take into consideration the clip alteration that will happen, particularly in respects to imaging the injured patient. At present, MRI of the articulatio genus requires about 30 proceedingss with our current protocol consisting of 6 sequences. The alteration in protocol uses 4 sequences, therefore perchance cut downing the scanning clip. However, using fat impregnation with a sequence tends to increase scanning clip. The add-on of another sequence that requires fat impregnation, or the STIR sequence, could well increase the sum of clip required for a knee scan. It is still a argument as to whether these excess sequences are necessary. Sequences such as the 3-dimensional spoilt gradient-echo and STIR sequences may go unneeded for the separate rating of gristle and bone marrow alterations, particularly in injured patients ( Davies & A ; Cassar-Pullicino 2002 ) .DecisionMRI is progressively going the aureate crit erion in measuring the articulatio genus articulation. It provides a more easy come-at-able, less invasive, and comparatively less dearly-won alternate to arthroscopy. It besides provides the injured patient a comparatively easy and comfy manner of obtaining all right elaborate imagination of their articulatio genus. Although most imaging centres have set standard protocols for MRI of the articulatio genus, these protocols may sometimes necessitate accommodation in order to outdo profit the patient. In order to make up one's mind which protocol is more suited, we must first take into consideration what consequence each sequence will hold on diagnostic truth, curative impact, and the degree of patient comfort.
Thursday, January 9, 2020
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