4T MRI Knee Protocol at the Wesley Hospital in Australia - Research Proposal Example

Review 4 T MRI Knee protocol at the Wesley Hospital in Brisbane/Australia. Introduction Musculoskeletal trauma of the knee joint remains the mostcommon cause of long-term disability. A significantly low percentage (10%) of the injuries recorded annually, were low-severity injuries, and serious non- fracture knee injuries also remain relatively rare, recorded at approximately 1 out of 50 injuries. Ligament tears form the large amount of serious non-fracture knee injuries at about 40%. Among the serious non-fracture knee injuries anterior cruciate ligament (ACL) tears are about 46 %, while medical collateral ligament (MCL) tears make up about 29% of the serious non-fracture knee injuries. Posterior cruciate ligament (PCL) injuries are the most rare injuries.(1- JM) Most suspected knee disorders become diagnosed first through conventional radiographs (X-rays). These radiographs are effective in demonstrating fractures because the show bones and joint spaces. Their sensitivity to soft tissue conditions remains low except in conditions where the tissues contain mush calcium or fat. X-rays are also relatively insensitive to destruction of medullary bone and loss of cartilage as well. The basic examination consists of lateral and ante posterior (AP) projections of the knee.(Carmen Martı´n-Herva´s) Radiographs and CTs remain effective modalities for post-operative imaging following ACL reconstruction. CTs, however, depict femoral tunnel in more accurate manner than radiographs. The radiation dosage however, is almost double that of the radiographs and this should be effective considered when utilizing CTs over radiographs ( Anagha et al). Plain radiographs provide limited assistance in dealing with sports related injuries. They can only be indicated in circumstances where there is significant impact injury. Positive findings are however, occasionally demonstrated in ACL disruptions, where there is depression of the lateral femoral notch, and segond fracture. Computed Tomography (CT) provides effective analysis for categorizing fracture of the tibia plateau. Ultrasound imaging is utilized minimally together with magnetic resonance imaging when analyzing many knee injuries. Ultrasound becomes reliable in assessment of quadriceps and patellar tendons, when symptoms of injury are located within the anterior joint, and are focal. Ultrasound easily identifies collateral ligaments. Injuries to these ligaments are however associated with derangement and MRI becomes essential in demonstrating the full spectrum of the injury (12- EUGENE G). MRI utilizes high soft tissue contrast and multiplanar capability in presenting precise anatomical examination of knee tendons, ligaments, menisci, bones, cartilage, synovium and diseases involving these body tissues. ( 2Y. L. CHAN). The utilization of MRI in assessment of knee injuries remains an indispensable clinical tool for managing chronic injuries. In the assessment of acute knee injuries, MRI remains limited but is becoming increasingly popular because of the accuracy. The MRI method has been effectively utilized in assessment of ACL injuries and other associated injuries (Darren).this paper seeks to present methods for improving the MR protocol of ACL tears imaging that is used by 4T MRI Siemens scanner at Wesley Hospital in Brisbane for more accurate diagnosis of the ACL tears. Aim: The project aims at reviewing 4T MRI Knee protocol for detecting anterior cruciate ligaments tears at Wesley Hospital in Brisbane/Australia. This will involve covering the following points: Anatomy and physiology of the Knee joint. Physical assessment of Knee joint injuries. Methods of imaging Knee joint. Normal appearance of Knee joint and its structures. Knee injuries. Focus on Anterior Cruciate Ligament (ACL) tears injuries. Pathogenic tears. Mechanism of ACL tears. ACL reconstruction. Advantages and disadvantages of using high magnetic fields. strength in scanning Knee. Advantages and disadvantages of using low magnetic field strength in scanning Knee joint. Common artifact seen in MR knee imaging. Review best current used MR imaging protocols of Knee joint for detecting ACL tears and abnormalities. As a part of the aim, several Knee MR images from different patients that had been scanned at Wesley Hospital using 4T MRI Knee protocol will be reviewed and evaluated to assess the adequacy of the protocol in detecting anterior cruciate ligament injuries. The findings of the project will be essential in providing recommendations to improve 4T MRI Knee protocol for detecting anterior cruciate ligament tears at Wesley Hospital in Brisbane/ Australia. Justification: Many reasons exist for undertaking this research including: 1. MRI could be defined as an evaluation of the internal structures of the knee which include menisci, cruciate ligaments, and articular cartilage. Though the method presnts different accuracy levels, within different structures, it produces results which are very close to those of arthroscopy, which is the generally acceptable method for assessing knee injuries. MRI can be effective in substituting arthroscopy, as the acceptable imaging modality for assessment of acute and chronic knee injuries (4-Harish). 2. The number of anterior cruciate ligament (ACL) injuries has been increasing, with reported injuries being between 100,000 and 200,000 anuallly within the united states alone. The numbers continues to increase with population and increased participation in sporting activities. Many of these injuries come from football (53%), while skiers and gymnasts are also high risk category of athletes. Women tend to be more susceptible to ACL injuries than men. The relative risk for injury among women in the United States Naval academy was established to be 3.96 for women, which was higher than that of men. The National Collegiate Athletic Association Injury Surveillance System also found similar results when making comparison of injuries between 1990 and 2002. This study involved analysis of soccer and basketball. (5Leon Siegel). 3. MRI remains one of the most accepted imaging modality in undertaking diagnosis of workups among patients with knee related problems, and continuously gained popularity over the traditionally preferred arthroscopy. MRI remain capable of depicting abnormalities among soft tissues such as meniscal lesions, cruciate ligament and collateral ligament lesions, tendinous lesions, and loose bodies, which are commonly analyzed using arthroscopy. Other problems like radiographically occult fractures, bone marrow edema, and osteochondral lesions can also become effectively diagnosed with MRI. The method has been identified as having higher accuracy when compared to arthroscopy, regarding meniscal tears and cruciate ligament injuries (9-Edwin). 4. MRI remains extremely valuable in ACL reconstruction. The accurate visualization of double-bundle anatomy and the evaluation of AM and PL bundles remain aspects which have been enhanced by special protocols of MRI. The method can effectively and accurately detect rupture patterns, through measuring insertion site size, angle of inclination, ACL and graft size, and post-operative complications (6-Paulo Araujo). 5. ACL injuries cause immense concern to careers of soccer players. The ligaments have a fundamental role in enabling individuals to twist, turn, jump and make other maneuvers. Surgical reconstruction remains inevitable when injuries occur to these ligaments. There is still limited knowledge on the capability of the knees to return to full functions once the reconstruction has been undertaken. The increased number of participants within the risky games continues to cause immense concern for a permanent solution to be sought. The technical changes including increased playing speeds have resulted in the increased number of injuries sustained annually. The diffusion of football activities in Europe has essentially made ACL a necessary element of the body, which must be extensively studied (7-PAOLO). 6. MRI has become a generally accepted non-invasive approach for investigating knee injuries sustained during sporting activities. The method presents high negative prediction value and becomes essential in avoiding the undertaking of knee arthroscopy to assess sustained injuries. The method has been identified as having diagnostic accuracy of 89% on meniscal tears and ACL tears, with sensitivity in detecting these injuries being more than 90%. The approach is also presumed better than arthroscopy in the assessment of posterior horn. Fundamental changes within the Australian government have resulted in the expansion medical funded MRI services. Individuals of all ages can be referred to MRI services following clinically appropriate indications. These indications will include MRI knee investigations for possible internal joint derangement (8Sarah Skinner ) 7. MRI has been identified by many medical practitioners as a reliable and cheaper alternative to “diagnostic arthroscopy”. While patients with clinical sings could be subjected to therapeutic arthroscopy, investigations into knee injuries will remain limited to the MRI, for diagnosis. The adoption of this policy enables many individuals to avoid unnecessary and expensive surgeries since MRI is non-invasive. The utilization of arthroscopy in diagnosis will remain limited to specific purposes, which the approach becomes identified as necessary and unavoidable. Arthroscopy of the knee has been reported as to produce negative results ranging between 29-50% of the cases diagnosed, while MRI provides accurate and reliable diagnosis to meniscal and cruciate injuries. Though interpretation of the findings remains difficult, accuracies of between 89-93% have been reported for meniscal tears and 95-98% for cruciate ligament injuries (10-I. W. CARMICHAEL). 8. MRI remains one of the most widely utilized methods for diagnosing ACL tears. ACL tears on T2-weighted or proton density weighted (TW2) sequences, when using MRI, remain clearly understood. Without the discrimination between complete and partial tears, studies have produced results indicating high accuracy levels in diagnosing ACL injuries, in general. (11Cyrille). 9. The MRI protocols remain different between various healthcare institutions, general practice diagnosis requires the assessment to be performed in three orthogonal planes (axial, sagittal, and coronal), and at least a sequence for analyzing fat saturation should be obtained Deepa R. (2011). The application of a protocol for standard protocol knee trauma or pain includes a sagittal proton density sequence without fat saturation and sagittal, coronal, and axial proton density images with fat saturation. The Images are obtained at a 3-mm slice thickness with a 1-mm interslice gap. A 3D sagittal water-selective excitation sequence or 3D spoiled gradient-recalled echo with fat saturation sequence provides excellent assessment of the articular and physeal cartilage (Deepa R). 10. Sequences of diffusion are generally utilized to ascertain diffusion fo free water in body tissues. A ligament fragment (rich in collagen and very poor in water) produces hypointense signal on ADC mapping. It becomes surrounded by a hyperintense signal corresponding to the fluid infiltration, which is induced by traumatic tear of the ligament and its surrounding tissue. Within this post-traumatic oedema, in becomes difficult to analyse the ACL on T2W sequences. ACL collagen fibres are hypothesized to be more visible on ADC mapping, and would this enables verification regarding the ligaments’ continuity. When ADC mapping is applied to traumatic ACLs it also improves differentiation between complete and partial tears, when compared with other studies that used only conventional T1 and T2 sequences. Applying ADC mapping to standard T1 and T2 sequences significantly enhances the specificity of MRI diagnosis for complete ACL tears, compared with using the T1 and T2 sequences alone. Also, it has been found that, an increase in sensitivity, non-significant probably because standard MRI sensitivity is already very high (11-Cyrille). 11. The unique diagonal course of anterior cruciate ligament (ACL) of knees, has enabled various MR imaging techniques to be investigated in regard to their capacity for visualization of the ACL. Many of the investigation reports remain focused on the knee position and the utilization of oblique sagittal images. (14-SUNG HWAN) found that the utilization of additional oblique sagitall images improves the specificity and accuracy of the capacity to detect ACL tears. This improvement of accuracy when utilizing oblique coronal images remains essential in decision making process regarding appropriate treatment for ACL, and related problems ( 14-SUNG HWAN). 12. Sung Gyu (2008) also found that the use of additional oblique coronal images significantly improved both the diagnostic accuracy and the diagnostic confidence for grading ACL graft injuries. Using the oblique coronal images also increased the specificity and accuracy of ACL graft tear, and this becomes essential in helping physicians to make correct clinical/surgical decisions when treating these ligament injuries. 13. the 4T MRI Siemens scanner in Wesley Hospital in Brisbane, which is owned and managed by the University of Queensland, improve the MR protocol utilized in accurately diagnosing ACL tears, within the hospital. Hypothesis: The Wesley Hospital 4T MRI Knee protocol is adequate for visualization of ACL tears. Method: There are two sections in the methods of this project: Section (I) Literature review, which is a comprehensive review of various academic material from different electronic databases which include: the Wiley Online Library, University of Queensland library, TheCochrane Library, SpringerLink, CINaHL, ScienceDirect, MEDLINE, and OvidSP. The selected articles were articles published from 2004 up to date. This was done to ensure the information contained within the project remains updated, since earlier articles might have outdated information; hence were excluded as part of the study. The following terms were used in the search for the articles Moreover, the terms used in the search should preferably have the phrases Knee Anatomy and Physiology, ACL reconstruction, ACL tears classification and grading, advantages and disadvantages of High and Low field MR magnet systems, artifacts encountered in Knee MR imaging, best MRI protocols and sequences for ACL tears imaging, Factors affect signal to noise (SNR) and resolution in Knee MR imaging, Gold standard methods for ACL imaging, Knee injuries, and ACL tears, Part (II) review 4T MR Knee protocol for ACL tears imaging at Wesley Hospital in Brisbane/Australia. This includes viewing knee MR images for ACL tears and subsequently grading the tears where present. Equipment: Writing and the subsequent activities of editing the dissertation will be undertaken using the Microsoft Office suite. The data collection processes within the study will utilize electronic databases and a personal password-protected laptop to ensure safety of the information. Several MR images will be acquired from the hospital for analysis of ACL knee tears. All the images utilized for this purpose have been taken by 4T MRI scanner at Wesley Hospital in Brisbane using ACL tears protocol. Bibliography: Read More