Intra-Trial Reliability and Usefulness of Isometric Mid-Thigh Pull Testing on Portable Force Plates.

The aim of this study was to assess the intra-trial reliability and usefulness of portable force plates and a customised Isometric Mid-Thigh Pull rig. Twenty males (age: 24.1 ± 2.5 years, body height: 177.7 ± 0.09 cm, body mass: 88.4 ± 17.9 kg) with weightlifting experience ± 12 months attended 1 familiarisation session and 1 testing session where 4 isometric mid-thigh pulls were performed. Maximum force, absolute peak force (PF), relative PF, allometrically scaled PF, and force (150, 200, 250 ms) were deemed reliable (ICC ≥ 0.91 and CV ≤ 9.8%) based on predetermined criteria (ICC ≥ 0.8 and CV ≤ 10%). The impulse and the rate of force development (RFD) were deemed unreliable (ICC ≤ 0.91 and CV ≥ 10 %) at all time points. Maximum force, absolute PF, relative PF to body weight and body mass, rand allometrically scaled PF, had a typical error (TE) lower than the smallest worthwhile change small effect (SWC0.2) and moderate effect (SWC0.5) and were rated as good with regard to usefulness. The TE for force at selected time points (150, 200, 250 ms) was also higher than the SWC0.2, achieving a rating of marginal, but TE was higher than SWC0.5, achieving a rating of good with regard to usefulness. Portable force plates and customised rigs can reliably determine peak force and force output at different time points and for detecting the SWC in maximum and absolute force measures, greater familiarisation may be required to establish reliability of other variables such as the impulse and the RFD.

Evaluation of adult outpatient magnetic resonance imaging sedation practices: are patients being sedated optimally?

PURPOSE: To evaluate the use of anxiolytics in adult outpatient magnetic resonance imaging (MRI) centres and to determine whether utilisation is optimal based on the pharmacology of the drugs used, who prescribes these drugs, and how patients are managed after administration. MATERIALS AND METHODS: Identical paper and Web-based surveys were used to anonymously collect data about radiologists' use of anxiolytic agents for adult outpatient MRI examinations. The survey questions were about the type of facility, percentage of studies that require sedation, the drug used and route of administration, who orders the drug, timing of administration, patient monitoring during and observation after the study, use of a dedicated nurse for monitoring, and use of standard sedation and discharge protocols. The chi(2) analysis for statistical association among variables was used. RESULTS: Eighty-five of 263 surveys were returned (32% response rate). The radiologist ordered the medication (53%) in slightly more facilities than the referring physician (44%) or the nurse. Forty percent of patients received medication 15-30 minutes before MRI, which is too early for peak effect of oral or sublingual drugs. Lorazepam was most commonly used (64% first choice). Facilities with standard sedation protocols (56%) were more likely to use midazolam than those without standard sedation protocols (17% vs 10%), to have a nurse for monitoring (P = .032), to have standard discharge criteria (P = .001), and to provide written information regarding adverse effects (P = .002). CONCLUSIONS: Many outpatients in MRI centres may be scanned before the peak effect of anxiolytics prescribed. A standard sedation protocol in such centres is associated with a more appropriate drug choice, as well as optimized monitoring and postprocedure care.

Comparison of MRI and sonography in the preliminary evaluation for fibroid embolization.

OBJECTIVE: The purpose of our study was to evaluate whether pelvic MRI provides additional clinically relevant information after sonography in the preprocedure evaluation of uterine artery embolization of fibroids. MATERIALS AND METHODS: Forty-nine women who presented for consultation for uterine artery embolization were retrospectively reviewed. The MRI and sonography scans were independently evaluated and compared for uterine size, fibroid size and location (categorized as paraendometrial, intramural, subserosal, or pedunculated) of the four largest fibroids in each patient, and the total number of fibroids present. RESULTS: One hundred twenty-two fibroids were measured. The uterine volume was significantly smaller as measured on MRI compared with sonography (p = 0.01). We found good MRI and sonography correlation of the volume of the single largest fibroid in each patient (R = 0.87) but poor correlation of fibroid location (R = 0.17). MRI detected 31 paraendometrial fibroids and three pedunculated fibroids that were thought to be intramural fibroids on sonography. Five fibroids thought to be paraendometrial on sonography were confirmed to be subserosal or intramural on MRI. Discrepancy in the total number of fibroids was noted, with additional fibroids found on MRI in 31 of 49 patients and erroneously suspected on sonography in five of 49 patients. Pelvic MRI affected management in 11 of 49 patients, leading to cancellation of uterine artery embolization in four patients. In another seven patients who were originally thought to be poor candidates on the basis of sonographic findings, uterine artery embolization was performed. MRI did not alter the management plan in 38 patients. CONCLUSION: MRI provided considerable additional information compared with sonography and affected clinical decision making in a substantial number of patients. MRI should be considered in all patients being evaluated for uterine artery embolization.

"Chasing the dragon"--imaging of heroin inhalation leukoencephalopathy.

"Chasing the dragon" refers to the inhalation of heroin pyrolysate vapors produced when the freebase form of heroin is heated. Inhalation of these vapors can result in a rare toxic spongiform leukoencephalopathy. The patients may progress through 3 defined clinical stages, with one-quarter reaching the terminal stage, which invariably leads to death. Imaging and, in particular, magnetic resonance imaging (MRI) demonstrates white matter findings that are felt to be specific for this entity and essential in its early diagnosis. We present the typical imaging findings in a pictorial essay format, using images taken from 9 patients who presented within an 18-month period at UBC-affiliated hospitals. These findings include low computed tomography (CT) attenuation and high T2 MRI signal most commonly in the posterior cerebral and cerebellar white matter, cerebellar peduncles, splenium of the corpus callosum, and posterior limb of the internal capsules. In addition, there is often selective, symmetric involvement of the corticospinal tract, the medial lemniscus, and the tractus solitarius. We also present the variable diffusion-weighted imaging and apparent diffusion coefficient findings from 4 of our patients, which to our knowledge, have not been described in the literature.

High-resolution sonography of the triangular fibrocartilage: initial experience and correlation with MRI and arthroscopic findings.

OBJECTIVE: The aim of our study was to compare the findings of high-resolution sonography of the triangular fibrocartilage with those of MRI and arthroscopy. SUBJECTS AND METHODS. Thirteen patients with clinically suspected triangular fibrocartilage tears prospectively underwent sonography, followed by MRI, of their wrists. Triangular fibrocartilage tears were classified as predominantly ulnar or predominantly radial. Only the surgeon was aware of the results of both studies, and eight patients subsequently underwent arthroscopy. The findings of the different techniques were compared. RESULTS: For the presence or absence of a tear, seven (87.5%) of eight sonographic examinations correlated with arthroscopy, and 11 (84.6%) of 13 sonographic examinations correlated with MRI. Sonography missed one small radial tear that was detected at arthroscopy and MRI, but sonography showed an ulnar tear in triangular fibrocartilage that appeared normal on MRI. CONCLUSION: High-resolution sonography shows good correlation with MRI and arthroscopy for the evaluation of triangular fibrocartilage tears. Sonography has the potential to be a rapid and cost-effective means of diagnosing tears of the triangular fibrocartilage, particularly those involving the ulnar aspect of the cartilage.

Imaging features of fat necrosis.

OBJECTIVE: We describe five cases of biopsy-proven fat necrosis and review the imaging with an emphasis on MRI. CONCLUSION: MRI showed the classically reported finding of central globular high signal intensity with a low-signal-intensity rim in only two of the five cases. We noted peripheral contrast enhancement, which to our knowledge has not been reported previously, in three of our five cases. Other patterns such as amorphous, cloudlike stranding and a serpentine appearance were also encountered. In reviewing the literature, we found that the MRI appearance of fat necrosis is more varied than previously thought.

Fibroid in the buttock: an unexpected diagnosis.

Uterine leiomyomas (fibroids) are very common lesions with well-described imaging features. We present an unusual case of a fibroid which presented in the buttock with atypical clinical and imaging features in a woman who had had a previous hysterectomy. Despite extensive imaging and biopsies, the diagnosis was not suspected until pathological evaluation of the resected mass. The differential diagnosis for such a lesion, and the imaging and pathological features of fibroids, including atypical and parasitic leiomyomas, are discussed.

Computed tomography of acute small bowel obstruction: pictorial essay.

In many patients, the diagnosis of SBO can often be made by a combination of clinical history, physical examination and plain radiographs. However, in many cases, the diagnosis of SBO may be difficult. Abdominal radiographs are limited in their ability to diagnose SBO and, more particularly, to identify a specific underlying cause. Although barium studies, ultrasonography and magnetic resonance imaging may all play a role in the evaluation of SBO, CT should be the examination of choice for most patients when the diagnosis and underlying cause of SBO is unclear. It may help differentiate pseudo-obstruction from true obstruction, and a specific underlying cause can often be determined. Signs of closed-loop obstruction, strangulation, perforation or infarction may be detected and allow for more timely and appropriate surgical management. We advocate the use of CT in any patient with SBO where the cause or diagnosis is unclear. We have attempted to demonstrate a range of clinical cases in our practice where CT played an invaluable role in the evaluation of our patients.

Neuroimaging features of heroin inhalation toxicity: "chasing the dragon".

OBJECTIVE: Our objective was to illustrate the dramatic neuroimaging findings of toxic leukoencephalopathy caused by heroin vapor inhalation. CONCLUSION: Symmetric abnormality involving the cerebellar white matter and posterior limb of the internal capsule is characteristic of heroin vapor inhalation toxicity, although involvement may be more extensive, depending on the severity of the condition. MR imaging and CT appear to be essential for making this diagnosis because clinical history is often unreliable and findings at physical examination are nonspecific.

Bilateral lipoma arborescens associated with early osteoarthritis.

Lipoma arborescens is a rare disease that has generally been considered to be unilateral. We report a case of bilateral disease in a patient with associated marked premature osteoarthritis of the knees. We postulate a possible association between these two conditions and explain a possible underlying mechanism. We suggest that lipoma arborescens be considered as a rare underlying cause of young patients with bilateral premature osteoarthritis, and recommend MRI as the definitive imaging modality.