Wallerian degeneration after cerebral infarction: evaluation with sequential MR imaging

The dynamic signal intensity changes at magnetic resonance (MR) imaging in active and chronic wallerian degeneration in the corticospinal tract were evaluated. Forty-three patients with wallerian degeneration seen on MR images after cerebral infarction were studied. When possible, patients with acute stroke were examined with MR imaging prospectively at the onset of symptoms and then at weekly intervals for several months. Focal infarction without distal axonal degeneration is demonstrated for the 1st month following onset of clinical symptoms. At 4 weeks, a well-defined band of hypointense signal appears on T2-weighted images in the topographic distribution of the corticospinal tract. After 10-14 weeks, the signal becomes permanently hyperintense. Over several years, accompanying ipsilateral brain stem shrinkage occurs. The dark signal intensity observed on T2-weighted images between 4 and 14 weeks is believed to result primarily from transitory increased lipid-protein ratio.     

Effect of volume load of the left ventricle in aortic and mitral insufficiency on the geometry and function of the right ventricle

To investigate the effect of chronic left ventricular enlargement on right ventricular geometry and function, biplane cineventriculograms were analyzed in 23 patients with aortic regurgitation (AR) and in 17 patients with mitral regurgitation (MR). Left ventricular end-diastolic volume indices (LVEDVI) were elevated and significantly (p less than 0.05) different in patients with aortic regurgitation (AR) (190.2 +/- 65.2 ml/m2) and mitral regurgitation (MR) (148.7 +/- 40.1 ml/m2). Right ventricular end-diastolic volume indices (RVEDVI), however, were comparable and within the normal range (AR: 96.6 +/- 18.3 ml/m2, MR: 100.2 +/- 33.7 ml/m2). Mean pulmonary artery pressure was significantly (p less than 0.05) higher in patients with mitral regurgitation with 24.7 +/- 12.8 mm Hg (AR: 17.5 +/- 6.6 mm Hg). Six patients with mitral insufficiency had concomitant tricuspid valve insufficiency. In five out of six patients with tricuspid insufficiency, right ventricular afterload was significantly elevated. Only in patients with mitral regurgitation was a significant correlation (r) between left and right ventricular end-diastolic volume index found (RVEDVI = 0.7 X LVEDVI +1, r = 0.80). Moreover, in patients with MR, left ventricular end-diastolic volume index correlated with right ventricular end-systolic volume index (RVESVI = 0.4 X LVEDVI -8, r = 0.73). Right ventricular ejection fraction was significantly different (p less than 0.05) between patients with aortic and mitral insufficiency (AR: 53.7 +/- 8.9%, MR: 46.7 +/- 10.7%). Particularly in patients with normal left ventricular ejection fraction (greater than 50%) and mitral regurgitation, the incidence of a reduced right ventricular ejection fraction (less than 50%) was significantly higher (p less than 0.01) compared to patients with aortic regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Management Strategies for Pain in Breast Carcinoma Patients: Current Opinions and Future Perspectives

Breast cancer is the most frequently encountered carcinoma in women worldwide. Pain is the most distressing symptom in patients with breast carcinoma and can occur at all stages of the disease due to the cancer per se as well as due to various diagnostic and treatment modalities. A proper pain assessment helps in identification of pain syndromes and guides in formulating analgesic strategies. Primary therapies of breast carcinoma like surgery, chemotherapy, and radiotherapy for bony metastases can cause substantial pain relief. However, multimodal analgesic approaches incorporating pharmacological, interventional as well as non-conventional techniques should be employed prior to, in conjunction with, and after primary therapies of breast cancer. The prevalence of chronic neuropathic pain following breast cancer surgery may exceed 50% by current estimates, and with the increase in life expectancy of these patients, providing adequate pain relief is of paramount importance to improve their quality of life. In this review, we discuss prevailing methods of evaluation and management of pain in patients of breast carcinoma and the new techniques that may become the mainstay of pain management protocols in future.     

Patterns of Insulin Dependence in an African Diabetic Clinic

SUMMARY Analysis of the age of onset of diabetes amongst insulin-treatedpatients in a large African diabetic clinic revealed a bimodaltype of distribution, 23 per cent having an age of onset before30 years and 77 per cent with onset at 30 years of age. All66 of the young insulin-treated group (21.7±4.8 years(mean±1 SD)), and a random selection of 50 older insulin-treatedpatients (49.7±10 years), were studied. The older groupwere better controlled (HbA₁ 8.4±1.7 per cent vs. 10.8±2.6per cent, p<0.001), on lower doses of insulin (49±23vs. 71±23 u/day, p<0.001) and had higher body massindex (26.0±5.6 vs. 21.8±3.5, p<0.001). SerumC-peptide (0.24±0.15 vs. 0.07±0.10 nmol/l, p<0.0001),and C-peptide/glucose ratio (2.57±2.65 vs. 0.56+0.98nmol/mmolx 10², p<0.001) were very significantly higher inolder patients. Patients with later onset disease thus had betterpreservation of pancreatic function, higher body mass indexand better glycaemic control on lower doses of insulin. Thesefeatures suggest that older insulin-treated patients could infact be ‘Type 2’ or non-insulin dependent patients,and the condition may be controllable with diet and/or oralhypoglycaemic agents, at least in some.     

The Importance of Early Carotid Endarterectomy in Symptomatic Patients

INTRODUCTION

Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.

PATIENTS AND METHODS

A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.

RESULTS

A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).

CONCLUSIONS

Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population.