Free flap reconstruction of the lower extremity in the elderly

Summary Over a four year period, thirteen patients over the age of 60 (mean 69 years) underwent reconstruction of lower extremity defects with free tissue transfers. Ten latissimus dorsi, one tensor facia lata, and two rectus abdominus free flaps were used. Despite significant risk factors which included previous tobacco use, hypertension, diabetes mellitus, and angiographic vessel abnormalities, ten of thirteen cases had successful outcomes. There was one acute flap failure secondary to arterial thrombosis. Four flaps had delayed healing, with one patient eventually requiring amputation secondary to persistent pain and wound drainage. This experience demonstrates that free flap reconstruction of lower extremity defects in the elderly patient is a reasonable alternative to amputation when other options are limited.From the Section of Plastic and Reconstructive Surgery at the Mayo Clinic and Mayo Foundation, Rochester, Minnesota, USA Requests for reprints: J. Fisher, M.D.     

Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging

Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.     

Outcome of gestational diabetes in Bengali Asians living in an east London health district.

The characteristics and outcome of pregnancy complicated by gestational glucose intolerance are described in a consecutive series of 69 Bengali Asian patients and a parallel group of 22 Caucasian patients. The Bengali patients were older and of higher parity than the Caucasians and more frequently required insulin therapy. However, the outcome of pregnancy was similar in terms of antenatal clinic attendance, the number of antenatal hospital admissions, glycaemic control, birthweight and mode of delivery. Of those patients who attended for postnatal glucose tolerance test, 20% of the Bengali population demonstrated persisting abnormality of glucose tolerance, whereas no abnormalities were evident in the Caucasian group. These findings are consistent with the high prevalence and early age of onset of non-insulin-dependent diabetes in Asian populations. The World Health Organisation (WHO) criteria for the diagnosis of impaired glucose tolerance proved insufficiently sensitive for the diagnosis of gestational diabetes. This was particularly demonstrated by four patients with apparently normal glucose tolerance by WHO criteria who subsequently required insulin therapy.     

Experience with high-dose gadolinium MR imaging in the evaluation of brain metastases.

PURPOSE: To assess the effectiveness and safety of higher doses of gadoteridol in the MR evaluation of patients with brain metastases. MATERIALS AND METHODS: Thirty-one patients with a clinical suspicion of brain metastases were studied prospectively with gadoteridol, a new, nonionic, low-osmolality contrast agent. Each patient received an initial injection of 0.1 mmol/kg and an additional dose of 0.2 mmol/kg 30 minutes later. Images were obtained before, immediately after, and 10 and 20 minutes after the initial dose. Images also were acquired immediately after the additional dose of gadoteridol. RESULTS: No adverse effects were attributed to the injection of gadoteridol. Four patients' examinations were excluded from analysis because of machine malfunction (two patients) and excessive motion artifact (two patients). Four patients had no detectable metastases. After the additional dose of gadoteridol, there was a marked qualitative improvement in lesion conspicuity and detection. The conspicuity of 80 of 81 lesions was increased in the high-dose studies, and 46 new lesions were detected in 19 of 27 patients. Quantitative image analysis demonstrated a significant increase in normalized mean lesion contrast between the initial-dose and high-dose studies (35 lesions identified in 13 patients, P less than .0001). The additional information gained by high-dose examinations contributed to a potential modification of the treatment in 10 of 27 patients. High-dose examinations increased flow-related artifact in the posterior fossa in 12 of 27 patients. CONCLUSION: Based on our preliminary results, high-dose gadolinium-enhanced MR examinations may have advantages over 0.1 mmol/kg examinations in detecting early and/or small metastases. This may be significant in the management of patients with cerebral metastases.     

Comparison between epidermal growth factor, transforming growth factor-alpha and EGF receptor levels in regions of adult rat brain.

Examination of adult rat brain regions by specific radioimmunoassays revealed a widespread distribution of transforming growth factor-alpha (TGF-alpha), but not epidermal growth factor (EGF), the peptide that had previously been reported to be present in rodent brain. Polyadenylated RNA samples from the different regions of rat brain were analyzed by Northern blot to identify mRNA species encoding precursor proteins for EGF (preproEGF), TGF-alpha (preproTGF-alpha), and the EGF/TGF-alpha receptor. The results indicate that TGF-alpha is the most abundant ligand for the EGF/TGF-alpha receptor in most parts of the brain analyzed. Message for preproEGF was only detectable after prolonged autoradiographic exposure; levels of preproEGF mRNA were between two and three orders of magnitude lower in brain than those expressed in control tissue (kidney), and one to two orders of magnitude lower than preproTGF-alpha mRNA levels in all brain regions. These results were confirmed by analysis of mRNA by RT/PCR, and support the hypothesis that expression of preproEGF mRNA in the brain is limited to smaller discrete areas, whereas preproTGF-alpha gene expression is almost ubiquitous.