Predictors of recurrence of chronic subdural haematoma in a cohort study of patients presenting in a sub-Saharan African teaching hospital.

BACKGROUND: Chronic subdural haematoma (CSDH) is a common neurological condition affecting the elderly with decreased quality of life. Recurrence leads to increase in number of hospital admissions and surgical interventions. Several factors contribute to recurrence of chronic subdural haematoma, and determination of these factors will help institute measures to reduce recurrence of CSDH, cost of care and improved quality of life. The aim of this study was to determine the predictors of recurrence of chronic subdural haematoma in a cohort of patients presenting in a Sub-Saharan African Teaching Hospital. METHODS: A prospective hospital-based cohort study of 62 participants who presented with CSDH and underwent burr-hole and drainage at the Neuroscience unit of the Korle-bu Teaching Hospital. The primary outcome of this study was the recurrence of CSDH within 3 months after the surgery. Data was entered into Microsoft Excel 2016 and exported to International Business Machine (IBM) Statistical Package for the Social Sciences (SPSS) version 21.0 for analysis. Predictors of recurrence of CSDH were determined using logistic regression with odds ratio calculated at the 95% confidence level and a p-value less than 0.05 accepted as statistically significant. RESULTS: There was a male preponderance of 45 (72.6%), over females of 17 (27.4%). The mean age was 63.1 ± 13.6 years. The recurrence rate of CSDH was 21.0% whilst the mortality rate was 4.8%. Facial palsy and dysphasia were associated with the recurrence of CSDH (p = 0.045, 0.029). Hypertension and bilaterality were associated with recurrence of CSDH from a univariate analysis (p = 0.039, OR = 4.865, CI = 0.975-24.285; p = 0.005, OR = 5.979, CI = 1.585-22.557). In a multivariate logistic regression analysis, bilaterality was the only independent predictor of recurrence of CSDH (p = 0.030, AOR = 5.47, CI = 1.18-25.34). CONCLUSIONS: Both hypertension and bilaterality showed statistically significant association with recurrence of CSDH. However, only bilaterality proved to be an independent predictor of recurrence of CSDH in patient who underwent burr-hole and drainage.

Normal MR anatomy and techniques for imaging of the male pelvis.

MR imaging has enhanced our ability to evaluate anatomic and pathologic processes in the male pelvis. Its remarkable soft-tissue contrast provides a unique depiction of the internal anatomy of the pelvic organs. Coupled with this superior soft-tissue characterization, its multiplanar capacity allows for greater depiction of tumor extension and staging. This article discusses some general MR techniques and concepts about MR imaging of the male pelvis and the normal MR anatomy and specific MR imaging techniques regarding each of the male pelvic organs.

A probe for specimen magnetic resonance microscopy.

One of the primary limits to spatial resolution in magnetic resonance (MR) microscopy is the limited signal. The purpose of this study is to build a radiofrequency (rf) probe for MR microscopy of fixed specimens at 300 MHz. The design criteria for the probe were (1) high sensitivity; (2) good rf homogeneity; (3) minimization of BO variations. All probes were Helmholtz pairs operating at 300 MHz. Coils were constructed from copper/Teflon/copper microwave substrate which eliminated susceptibility problems from solder and discrete capacitors. Signal-to-noise ratio (SNR) was compared with a conventional solenoid. Phantoms of agar gels and saline-filled tubes were used to characterize the SNR and homogeneity. SNR measurements of the coil pairs showed a marked improvement (up to 60%) over that of the reference solenoid. The region of homogeneity was defined as a 10% variation in signal intensity. This correlated with the coil's inner diameter. Graphs of SNR versus diameter, separation, and copper foil width allowed for optimization of the structure. Using this coil, MR microscopy is now possible on small, fixed specimens with pixels as small as 20 x 20 x 30 microns. Work is currently under way exploiting the SNR and homogeneity provided by this probe to determine the degree to which MR microscopy might add to the pathologists' diagnostic tools.

Surface coil imaging of rat spine at 7.0 T.

An inductively coupled surface coil for imaging the rat spine at 7 T is described. This planar circular probe was made from microwave substrate to limit the size of the coil and to minimize the magnetic susceptibility. The surface coil was used as a single transmit/receive coil and as a receive-only coil with a birdcage body coil for excitation. The signal-to-noise ratio (SNR) of the probe was compared to a 5-cm birdcage coil and exceeded the birdcage coil's SNR by three to six times at superficial structures. The main advantages of the probe are an improved SNR for superficial structures and a simple design and use. Images with 50 x 50 x 500 micron voxels were obtained of the rat spine with excellent anatomical detail.