Utility of magnetic resonance imaging in diagnosing ulnar neuropathy at the elbow.

OBJECTIVE: Magnetic resonance imaging (MRI) of the ulnar nerve is being increasingly employed in the diagnosis of ulnar neuropathy at the elbow (UNE). Our aims were to: (i) assess the sensitivity of MRI in diagnosing UNE, especially in cases where neurophysiologic studies were non-localizing, (ii) determine the spectrum of MRI abnormalities in patients presenting with symptoms and signs of ulnar neuropathy, (iii) assess whether MRI findings differ between grades of UNE severity, and (iv) to see if MRI findings give an input into the pathological mechanisms of UNE. METHODS: Clinical, neurophysiologic, and radiologic (MRI) records were reviewed in 52 patients with symptoms and signs of ulnar neuropathy. Ulnar nerve MRI studies were assessed by an unblinded observer. RESULTS: The sensitivity of MRI at diagnosing UNE was higher than conventional nerve conduction studies, 90 versus 65%, respectively. In patients with non-localizing neurophysiologic studies (n=19), MRI disclosed changes consistent with UNE in 16 (84%) cases. The most frequent MRI findings included a combination of high signal intensity and nerve enlargement (63%), followed by nerve compression (27%) and isolated high signal intensity (23%), and isolated nerve enlargement (2%). There was no significant difference between patients with localizing and non-localizing neurophysiologic testing. Lastly, there were no differences between different grades of UNE, suggesting that UNE may be a neurophysiologically heterogeneous disorder. CONCLUSIONS: MRI studies proved to be more sensitive than conventional nerve conduction studies at diagnosing UNE. In addition, the MRI studies were highly sensitive in patients with non-localizing UNE. SIGNIFICANCE: Our study shows that MRI of the ulnar nerve should be used in patients with clinical features of UNE especially in those with non-localizing neurophysiologic testing.

Nocturnal blood pressure predicts left ventricular mass index in normotensive elderly.

Blood pressure (BP) predictors of left ventricular mass index (LVMI) were studied in 40 healthy normotensive (71.4 +/- 4.4 years) and 31 hypertensive (73.5 +/- 4.8 years) elderly community-dwelling subjects using short-axis cardiac cine magnetic resonance imaging and 24-h ambulatory BP monitoring. Mean night-time BPs were calculated from the average of readings during sleep and mean daytime BPs were calculated from the remaining recordings. The hypertensive subjects were all receiving anti-hypertensive therapy with angiotensin-converting enzyme (ACE) inhibitors, calcium-channel blockers, beta-blockers or diuretics. Nocturnal systolic BP was a strong predictor of LVMI in both normotensive (beta = 0.38, p = 0.02) and treated hypertensive (beta = 0.39, p = 0.03) subjects. By contrast, daytime systolic BP was a weaker predictor of LVMI in the treated hypertensives (beta = 0.36, p = 0.04) and did not predict LVMI in the normal subjects (beta = 0.27, NS). Nocturnal BP may partly explain the increase in LVMI with ageing in subjects thought to be normotensive on the basis of daytime clinic BP recordings.

Reproducibility study of left ventricular measurements with breath-hold cine MRI using a semiautomated volumetric image analysis program.

The reproducibility of a semiautomated method of volumetric analysis allowing estimates of left ventricular (LV) parameters in approximately 5 minutes of analysis time is reported. Twenty normal volunteers underwent cine breath-hold cardiac MRI on two occasions with two observers using this new semiautomated method to estimate LV parameters. Reproducibility of this technique was comparable to published data with a variability of less than approximately 10% for all LV parameters calculated. Using this technique, the 95% confidence limits for change for left ventricular end diastolic volume (LVEDV) = +/-15 ml, left ventricular end systolic volume (LVESV) = +/-8 ml, LV mass = +/-24 g, and left ventricular ejection fraction (LVEF) = +/-6%. This new method also compared favorably to established manual methods. This new method permits estimation of LV parameters with acceptable reproducibility in a time that may permit routine quantitation of cardiac MR studies.

Labrocapsular ligamentous complex of the shoulder: normal anatomy, anatomic variation, and pitfalls of MR imaging and MR arthrography.

Magnetic resonance (MR) imaging is a useful modality for evaluating the labrocapsular ligamentous complex (LCLC) of the shoulder. MR arthrography is an important and occasionally indispensable supplementary modality for accurate differentiation between normal and deranged glenohumeral joints. Because of the joint distention that occurs during MR arthrography, it is especially helpful in detecting subtle capsular derangement, as occurs in patients with atraumatic instability. Also, some of the pitfalls associated with MR imaging of the LCLC are less likely to occur with MR arthrography. Radiologists should look for several key abnormalities when evaluating MR images of the shoulder: an anterior or posterior Bankart lesion; a Hill-Sachs defect; a tear of the rotator cuff, glenoid labrum, or superior labrum-biceps tendon attachment; and loose bodies. Knowledge of normal anatomy, normal variations, and pitfalls in image interpretation related to evaluation of the LCLC will help the radiologist accurately detect debilitating derangements associated with glenohumeral instability.

The relationship between tests of lung function and three chest radiological scoring systems in patients with cystic fibrosis.

The chest radiographs and lung function tests of 41 patients attending the cystic fibrosis clinic at Royal Prince Alfred Hospital were reviewed. The chest radiographs were scored using three different scoring systems: the Shwachman and Kulczycki system (as modified by Doershuk), the National Institute of Health (NIH) system described by Taussig in 1973 and the Brasfield system. The scores were correlated with lung function tests. Significant correlations were found between the radiological scores and the respiratory variables; the best correlation was with the forced expiratory volume in one second (FEV1 % predicted). All three scoring systems showed a high degree of reproducibility of scores when a second radiologist was asked to score the same radiographs independently. The difference in scores between the radiologists was not significant for the NIH and the Brasfield systems. The Brasfield system is, however, the system of choice because it allows the assessment of all the major pathological features seen in cystic fibrotic chest films and consistently has the best agreement with all the lung function variables. It was also found that radiological evidence of lung hyperinflation may not be a good indicator of disease progression.

Central nervous system tuberculosis in Australia: a report of 22 cases.

OBJECTIVE: To review the clinical features, treatment and outcome of patients with central nervous system (CNS) tuberculosis. DESIGN AND SETTING: A retrospective analysis of the case records of patients diagnosed as having CNS tuberculosis in a large Australian teaching hospital. PATIENTS: Twenty-two patients with CNS tuberculosis were identified between 1978 and 1989. Six patients (age range, 17-78 years) were Australian-born whites, seven patients (age range, 21-68 years) were overseas settlers in Australia and nine patients (age range, 14-56 years) were New Caledonians. The diagnoses included tuberculous meningitis, intracranial tuberculomas and intracranial tuberculous abscesses. These were confirmed by microbiology and/or histopathology in 16 patients and were presumptive in the remaining six. RESULTS: All patients were treated with antituberculous drugs and 14 received corticosteroids as well. Fourteen patients made a full recovery and two had mild residual neurological disability. Four patients died and two were left with severe residual disability. The neurological state of seven patients (all non-whites) deteriorated paradoxically after they started taking the antituberculous drugs. CONCLUSIONS: The diagnosis of CNS tuberculosis may be difficult to make, so therapy based on a presumptive diagnosis will often be needed because of the poor outcome if treatment is delayed. Computed tomographic scanning helps the initial diagnosis and demonstrates the processes underlying paradoxical deterioration, which may occur in the face of adequate antituberculous treatment. Corticosteroids are effective in treating this uncommon complication.