Biomedical subjects
Publications and source records attributed to Herbert M User.
Simple prostatectomy has been a mainstay of therapy for patients with benign prostatic hyperplasia. We describe a preperitoneal laparoscopic approach for resection of large prostatic adenomas. We believe this is a viable and less invasive alternative to the traditional open approaches used for simple prostatectomy.
Laparoscopic radical prostatectomy is rapidly gaining popularity. Several techniques have been described to retract the prostate. We have developed a technique using a urethral catheter that is simple to reproduce and provides stationary anterior countertraction on the prostate that does not require an assistant.
PURPOSE: To evaluate our experience with the LithoTron lithotripter (Healthtronics, Atlanta, GA), a dry portable system that utilizes a spark-gap electrode as an energy source. PATIENTS AND METHODS: We prospectively evaluated the first 312 treatments performed on 199 men and 99 women with an average age of 43.5 years (range 4 months-80 years), over a 25-month period between May 1999 and June 2001. Of the 468 stones treated, 136 were located in the ureter, 52 in the renal pelvis or ureteropelvic junction, and 230 in the kidney; the sites of 50 were not specified in our database. The average stone size was 8.0 mm (range 1-40 mm). Follow-up included a plain (KUB) film, CT scan, or intravenous urogram (IVU) and was available for 256 patients. "Stone free" was defined as no fragments visible on postoperative images. The mean radiographic follow-up was 74 days (range 0-866 days). Data collection was initially done manually by data sheets, but a Web-based medical database application was developed in order to enter, store, retrieve, and analyze the data more efficiently. RESULTS: The average number of shocks delivered per renal unit was 2689 at 25.8 kV. Seventy-five percent of the procedures were performed with intravenous sedation. Two thirds (169/256) of the patients were rendered stone free with one treatment. According to size, 71% (209/294) of stones <1 cm, 57% (39/68) of stones between 1.0 and 1.5 cm, and 22% (8/36) of stones >1.5 cm were eliminated. There were 23 patients who required further treatment; from the available data, 18 of them are currently stone free. Perioperative complications occurred in 6 patients (2%). No patient had worsening renal function or new-onset hypertension. The effectiveness quotient was 59.3%. CONCLUSION: The LithoTron lithotripter is satisfactory for stones <1 cm.
PURPOSE: The role of ureteronephroscopy in the diagnosis and treatment of upper-tract disease has expanded dramatically in recent years with technological advances. In a study involving 14 urologists, we measured the practical performance and durability of the most common commercially available flexible ureteroscopes. PATIENTS AND METHODS: Six commercially available flexible ureteroscopes (Circon-ACMI DUR 8, ACMI DUR 8-Elite, Storz 11274AA, Wolf 7325.172-7.5Fr, Wolf 7330.072-9.0 Fr, Olympus URF-P3) were used consecutively 102 times over a 7-month period. Comparative data, including preoperative and postoperative maximal deflection angles and luminosity, were accumulated, as well as a survey of insertion methods, irrigation methods, instruments used in the working channel, visibility, maneuverability, and overall satisfaction. Maintenance records were analyzed to evaluate the need or reason for repair. RESULTS: Overall satisfaction, visibility, luminosity, and maneuverability were similar for all instruments. The ACMI DUR-8 Elite scored slightly higher than the others, but the difference was not statistically significant. Ureteroscopes were used an average of 10 to 34 times between breakages. The ACMI DUR-8 and DUR-8 Elite instruments had a higher durability score than the others, but with significantly more uses. Channel perforation by a laser fiber was the predominant cause of ureteroscope breakage. CONCLUSIONS: All ureteroscopes performed similarly by objective and subjective criteria. The largest and newest instruments were significantly more durable than the smaller ones, even in the hands of numerous endoscopists. This finding has significant implications for the cost-effectiveness of the various ureteroscopes.
Hemostasis can be a challenging problem to control laparoscopically. We advocate the use of FloSeal Matrix. FloSeal can be used in a variety of open and laparoscopic procedures, including laparoscopic or open partial nephrectomy. FloSeal was highly effective in stopping bleeding in a bloody surgical field.
PURPOSE: We evaluated neurogenic erectile dysfunction, focusing on the post-radical prostatectomy model. We investigated changes in DNA, protein and apoptotic cells of the rat penis after denervation. Gross morphometry was measured to elucidate the impact of chemical changes. MATERIALS AND METHODS: Postpubertal male Sprague-Dawley rats were randomized to bilateral or unilateral cavernous nerve transection, or sham operation. Wet weight, DNA content and protein content were measured. Tissue sections were stained for apoptosis by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling and the apoptotic index was calculated. Dual staining was performed for endothelial and smooth muscle cells to identify apoptotic cells. RESULTS: Penile wet weight was significantly decreased at all time points after bilateral neurotomy (p <0.0005). Unilateral neurotomy allowed much greater preservation of penile weight. DNA content was significantly decreased in bilaterally denervated penes and unchanged in unilaterally operated penes. Protein content was not significantly altered in the bilateral or unilateral cohorts. Bilateral neurotomy induced significant apoptosis, while unilateral surgery caused significantly less apoptosis. Each population had apoptotic clustering just beneath the tunica albuginea, which was mostly smooth muscle cells. CONCLUSIONS: These data suggest the importance of neural integrity to maintain penile homeostasis. The loss in penile weight was consistent with the anecdotal experience of many clinicians. Decreased DNA content may have been due to significant levels of apoptosis in smooth muscle cells. Preserved protein content may suggest an increase in extracellular protein, as postulated in corporeal fibrosis. The subtunical population of apoptotic smooth muscle cells revealed a mechanism for veno-occlusive dysfunction observed after radical prostatectomy. These effects were significantly moderated in the unilateral model, reinforcing the critical nature of neural integrity.
PURPOSE: We focused on the post-radical prostatectomy model to advance the understanding of neurogenic erectile dysfunction. We attempted to identify previously undescribed molecular changes via gene discovery methods using GeneChip (Affymetrix, Santa Clara, California) microarray technology. MATERIALS AND METHODS: Five male adult 120-day-old Sprague-Dawley rats underwent bilateral cavernous nerve neurectomy. Five age matched controls were prepared simultaneously. The penises were harvested on postoperative day 2 and snap frozen in liquid nitrogen. RNA was prepared and pooled into cut and uncut groups. Synthesis of cRNA was performed according to the GeneChip technical manual. Microarray analysis was performed on a U34A Rat Array (Affymetrix). This array has approximately 8,800 gene probe sets, approximately 6,600 known genes and approximately 2,200 estimated sequence transcripts. RESULTS: Dramatic results were found during GeneChip microarray expression analysis. A total of 126 candidate genes were noted to be altered based on the magnitude of expression change using rigorous statistical criteria, including 47 that were down-regulated and 79 that were up-regulated. Among the many significant changes seen 1 dominant class of genes was the submandibular rat genes. Submandibular rat 1 (SMR1) was down-regulated 82.5 fold. Other genes in this family were down-regulated 226 and 90 times. This result was confirmed by reverse transcriptase-polymerase chain reaction and Western blot analyses. These assays verified decreases in SMR1 at multiple time points after surgery. CONCLUSIONS: Impressive and previously unrecognized genetic changes are being intensely investigated as they are being unmasked by GeneChip technology. We have identified and begun the investigation of 1 interesting family of genes, namely submandibular gland proteins. The role of SMR as a clinically relevant change in penile and/or urethral function following cavernous nerve injury is speculative.
PURPOSE: Renal entrapment for morcellation can be a difficult task, often necessitating additional port placement and awkward maneuvering as well as concern with specimen sack breakage. We describe a novel technique that combines the best features of existing technology to allow easy entrapment and safe morcellation. MATERIALS AND METHODS: We combined a 15 mm. EndoCatch II (United States Surgical Corp., Norwalk, Connecticut) introducer and frame with an 8 x 10-inch LapSac (Cook Urological, Spencer, Indiana) to facilitate entrapment with a strong reliable specimen sack. The LapSac is sutured in place onto the frame of the EndoCatch device with 3-zero sutures. The device is then rearmed and lubricated prior to introduction. RESULTS: The described modification greatly enhances our ability more rapidly and easily to entrap nephrectomy specimens prior to tissue morcellation. No additional ports are needed and no morbidity has resulted from the use of the modified entrapment device. Introduction and deployment of the modified entrapment device is straightforward and easily reproducible. CONCLUSIONS: We recommend this easy and secure technique when tissue morcellation is being considered.
PURPOSE: Laparoscopic renal cryosurgery provides a minimally invasive alternative for the treatment of small renal lesions of undefined malignant potential. We report on our series of patients treated with laparoscopic renal cryosurgery. MATERIALS AND METHODS: Fifteen patients underwent laparoscopic renal cryoablation of peripheral, exophytic unifocal renal lesions. Patients were managed with a 4-port transperitoneal approach for anteromedial tumors and 3 to 4-port retroperitoneal approach for posterolateral tumors. All lesions were biopsied and sent to pathology for permanent section. A 4.8 mm cryoprobe (CMS cryoprobe, 4.8 mm x 2 cm x 40 cm, Cryomedical Sciences Inc., Ewing, New Jersey) was placed into the tumor using visual and ultrasonographic guidance, and a double freeze-passive thaw cycle was performed. The iceball was extended at least 1 cm beyond the tumor margin under ultrasound guidance. Followup biopsies were performed on all consenting patients with renal cell carcinoma at least 3 months after cryosurgery was performed. RESULTS: Laparoscopic renal cryosurgery was successfully performed on all 15 patients (6 male and 9 female). Of the 15 patients 10 had renal cell carcinoma. Mean age was 68.5 years (range 49 to 86). Mean tumor size was 2.15 cm (range 1.2 to 3.2) and mean estimated blood loss was 67 cc (range 15 to 125). There were 2 perioperative complications. Mean hospital stay was 3.5 days (range 1 to 11). Patients returned to work after 16.5 days (range 7 to 28). Radiographic followup revealed stable cryoablative lesions in all patients. Mean radiographic followup was 453 days (range 147 to 816). Mean preoperative creatinine was 1.25 mg/dl (range 0.8 to 4.3) and mean postoperative creatinine obtained 1 month postoperatively was 1.36 (range 0.8 to 4.8). There was 1 treatment failure, although another patient had a positive biopsy outside the ablated area. The failure occurred in the largest tumor treated (3.2 cm) and was due to incomplete treatment of the periphery of the lesion. The other patient had a successfully treated tumor but a positive followup biopsy due to multifocal papillary renal cell carcinoma and required nephrectomy. CONCLUSIONS: Laparoscopic renal cryosurgery appears to be a safe and effective minimally invasive alternative for the treatment of small renal masses. Careful selection of patients with lesions that are less than 3.0 cm and close monitoring of the iceball is necessary to treat these patients successfully.
OBJECTIVE: Topiramate is a sulfamate-substituted monosaccharide anticonvulsant used as adjunctive therapy for intractable refractory seizures. It is report a case of topiramate-induced urolithiasis. CASE REPORT: A 35-year-old man presented with acute, right-sided, colicky flank pain. He denied hematuria or dysuria. He was in use of phenytoin, risperidone, phenobarbital, and topiramate. The total daily dose of topiramate was 375 mg. A CT scan showed a 7 x 1 mm curvilinear density at the right ureterovesical junction with proximal hydrouretronephrosis. He was managed with rigid ureteroscopic stone extraction and the calculus metabolic analysis revealed the stone was composed of carbonate apatite (70%), calcium oxalate dihydrate (20%), and calcium oxalate monohydrate (10%). COMMENTS: The present case typifies many features of topiramate-induced urolithiasis. Those who care for patients with urinary stone disease should be aware of this association.