Biomedical subjects

Michael W Phelan

Publications and source records attributed to Michael W Phelan.

3 recordsLinked to original sources

PubMed2003

Laparoscopic partial nephrectomy and minimally invasive nephron-sparing surgery.

Surgical extirpation remains the most effective therapy for renal cell carcinoma. The surgical management of renal masses has evolved away from radical nephrectomy and now includes nephron-sparing surgery for small tumors. Nephron-sparing surgery has similar cure rates and does not appear to compromise cancer control. As the detection of small renal masses by widespread abdominal imaging continues to increase, so will the demand for minimally invasive nephron-sparing procedures. Despite progress in surgical techniques, laparoscopic partial nephrectomy remains a technically challenging procedure. In this review, we discuss the challenges and recent advances in laparoscopic partial nephrectomy and other minimally invasive approaches to renal masses.

Carcinoma, Renal Cell↗

PubMed2003

Quality of life, pain and return to normal activities following laparoscopic donor nephrectomy versus open mini-incision donor nephrectomy.

PURPOSE: We evaluated pain, convalescence and health related quality of life in patients undergoing laparoscopic and open mini-incision donor nephrectomy. MATERIALS AND METHODS: We compared the records of consecutive patients who underwent laparoscopic and mini-incision open donor nephrectomy from our donor nephrectomy data base in retrospective fashion using 2 questionnaires. The first questionnaire evaluated postoperative pain, return to functioning time and satisfaction. The second questionnaire was the RAND 36-Item Health Survey, version 2, a standardized and validated health survey quality of life assessment tool. Mean patient sex, age and followup were similar for the 2 groups. All data were analyzed using the 2-tailed t test for independent variables with commercially available statistical analysis software. RESULTS: Pain in the laparoscopic group was significantly less than in the mini-incision group at all followup time points (p <0.05). Statistically significant differences demonstrated that laparoscopy led to more rapid recovery time in certain categories, including walking, discontinuation of prescribed oral pain relievers, return to driving, and resumption of normal work and home daily activities. More subjective questions in the survey showed high levels of acceptance for the 2 procedures. Using the RAND 36-Item Health Survey, version 2 health related quality of life was significantly higher in the laparoscopy group in 3 domains that measure bodily pain, physical functioning and emotional role functioning. However, each group scored at or above age matched American averages in all domains. CONCLUSIONS: The laparoscopy group had significantly less postoperative pain and required less time to return to normal functional activities than the mini-incision group. In addition, the laparoscopic group showed significantly higher quality of life scores than the mini-incision group in 3 domains.

Activities of Daily Living↗

PubMed2002

Diabetic cystopathy correlates with a long-term decrease in nerve growth factor levels in the bladder and lumbosacral dorsal root Ganglia.

PURPOSE It has been proposed that a deficiency in the axonal transport of nerve growth factor (NGF) may have an important role in inducing diabetic neuropathy, which contributes to diabetic cystopathy. Therefore, in streptozotocin (Sigma Chemical Co., St. Louis, Missouri) induced diabetic rats we investigated the relationship of bladder function with NGF levels in the bladder and lumbosacral dorsal root ganglia, which contain afferent neurons innervating the bladder. MATERIALS AND METHODS At 6 and 12 weeks after the induction of diabetes with streptozotocin (65 mg./kg. intraperitoneally) the effects of diabetes on Adelta afferent fiber dependent, conscious voiding were evaluated by metabolic cage measurements and awake cystometry. The effects of diabetes on C-fiber mediated bladder nociceptive responses were also investigated by cystometry with intravesical instillation of 0.25% acetic acid in the rats under urethane anesthesia. NGF levels in the bladder and L6 to S1 dorsal root ganglia were measured by enzyme-linked immunosorbent assay 3, 6, 9 and 12 weeks after streptozotocin injection. RESULTS In diabetic rats NGF levels in the bladder and L6 to S1 dorsal root ganglia were significantly decreased 12 weeks after streptozotocin injection (p <0.01). In cystometry and metabolic cage studies bladder capacity and post-void residual volume were significantly increased 12 weeks after streptozotocin injection (p <0.01). Bladder nociceptive responses revealed by a reduction in inter-contraction intervals after acetic acid infusion were significantly decreased in a time dependent manner 12 weeks after streptozotocin injection.CONCLUSIONS Rats with streptozotocin induced diabetes mellitus showed a significant time dependent decrease in NGF levels in the bladder and L6 to S1 dorsal root ganglia that was associated with voiding dysfunction attributable to defects in Adelta and C-fiber bladder afferents. Therefore, reduced production of NGF in the bladder and/or impaired transport of NGF to L6 to S1 dorsal root ganglia, which contain bladder afferent neurons, may be an important mechanism inducing diabetic cystopathy.

Animals↗