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Biomedical subjects

J W Konnak

Publications and source records attributed to J W Konnak.

At least 19 recordsLinked to original sources
PubMed2001

Randomized controlled trial of hand-assisted laparoscopic versus open surgical live donor nephrectomy.

BACKGROUND: Laparoscopic live donor nephrectomy for renal transplantation is being performed in increasing numbers with the goals of broadening organ supply while minimizing pain and duration of convalescence for donors. Relative advantages in terms of recovery provided by laparoscopy over standard open surgery have not been rigorously assessed. We hypothesized that laparoscopic as compared with open surgical live donor nephrectomy provides briefer, less intense, and more complete convalescence. METHODS: Of 105 volunteer, adult, potential living-renal donors interested in the laparoscopic approach, 70 were randomly assigned to undergo either hand-assisted laparoscopic or open surgical live donor nephrectomy at a single referral center. Objective data and subjective recovery information obtained with telephone interviews and validated questionnaires administered 2 weeks, 6 weeks, and 6-12 months postoperatively were compared between the 23 laparoscopic and 27 open surgical patients. RESULTS: There was 47% less analgesic use (P=0.004), 35% shorter hospital stay (P=0.0001), 33% more rapid return to nonstrenuous activity (P=0.006), 23% sooner return to work (P=0.037), and 73% less pain 6 weeks postoperatively (P=0.004) in the laparoscopy group. Laparoscopic patients experienced complete recovery sooner (P=0.032) and had fewer long-term residual effects (P=0.0015). CONCLUSIONS: Laparoscopic donor nephrectomy is associated with a briefer, less intense, and more complete convalescence compared with the open surgical approach.

Activities of Daily Living↗
PubMed2001

Revision rate after artificial urinary sphincter implantation for incontinence after radical prostatectomy: actuarial analysis.

PURPOSE: We determined the actuarial revision rate for artificial urinary sphincters implanted in patients who were incontinent after radical prostatectomy. MATERIALS AND METHODS: We reviewed the records of 70 consecutive patients who were incontinent after radical prostatectomy and who underwent primary artificial urinary sphincter implantation at the University of Michigan between 1984 and 1999. Questionnaires were mailed to all patients with an indwelling device, and telephone calls were placed to those who did not respond to the mailing. Information about surgical revision and current continence status was obtained from chart review and questionnaire response. The Kaplan-Meier curves for actuarial freedom from operative revision were constructed. RESULTS: Of the 66 patients with available postoperative data 24 (36%) required reoperation at a mean followup of 41 months. The 5-year actuarial rate for freedom from any operative revision was 50%, and the corresponding rate for cuff revision was 60%. A single operative revision did not predispose the patient to further revision. Questionnaire data indicated a continence rate of 80% (range 0 to 2 pads). CONCLUSIONS: Approximately half of the patients who were incontinent after radical prostatectomy may expect to undergo operative revision within 5 years after artificial urinary sphincter implantation. Despite this high reoperation rate, an excellent level of continence is maintained.

Actuarial Analysis↗
PubMed2000

Prospective, case matched comparison of hand assisted laparoscopic and open surgical live donor nephrectomy.

PURPOSE: The technical difficulty of standard laparoscopic live donor nephrectomy has limited its application. Hand assistance, which takes advantage of the incision necessary for organ removal, facilitates laparoscopy without significant impact on patient recovery. We prospectively compared open surgical and hand assisted laparoscopic donor nephrectomy. MATERIALS AND METHODS: Our first 10 laparoscopic live donor nephrectomies were matched with 40 open donor nephrectomies by gender, age and body mass index. Data were obtained by pain scales, SF-12 survey instruments, questionnaires and chart abstraction. RESULTS: Operative time was longer for the laparoscopic approach (mean 95 versus 215 minutes). However, laparoscopic group patients had a shorter hospital stay compared to those undergoing open surgery (mean 2.9 versus 1.8 days), returned sooner to nonstrenuous activity (mean 19.0 versus 9.9 days) and reported less pain 6 weeks postoperatively (mean 2.3 versus 0.6) (p </=0.03 for all). There were no differences between groups in terms of donor complications, allograft function and ureteral complications. Mean hospital cost was 23% greater in the laparoscopic group (p = 0.005) but global cost, which accounted for estimated loss of income from work during the recovery period, was only 15% greater (p = 0.10). Mean operative time was significantly improved for our second compared to our first 5 laparoscopic group patients (177 versus 254 minutes). CONCLUSIONS: Laparoscopic live donor nephrectomy appears to be a safe and effective alternative to open donor nephrectomy. Indexes of patient recovery suggest patient morbidity similar to that reported following standard laparoscopic donor nephrectomy and significantly less than after open nephrectomy. Improvement in operative time in the first 10 cases suggests that hand assistance "shortens" the learning curve, which might encourage more surgeons to offer laparoscopic live donor nephrectomy.

Adult↗
PubMed1999

Renal transplantation at the University of Michigan 1964 to 1999.

The Michigan Kidney Transplant Program has existed for 35 years. Outcomes have improved dramatically as the one-year survival of cadaver kidney grafts increased from 25% to 85-90%. Patient deaths in the first year are now uncommon. Indications for renal transplantation have been extended to infants, the elderly, diabetics and to patients with other significant health problems who would not have been candidates in the past. Chronic administration of large doses of corticosteroids is no longer necessary and the associated morbidity is largely avoided. Improvements in immunosuppression, especially the introduction of cyclosporine, account for much of this progress. With success has come increasing demand. Unfortunately, the gap between the number of available donor kidneys and the number of patients listed for a cadaver transplant continues to increase rather than diminish. Greater acceptance of volunteer donation, as has occurred in our own program, will help to reduce this shortage. If the past forecasts the future, we can anticipate extraordinary advances during the next 35 years.

Actuarial Analysis↗
PubMed1996

Potential renal donors: comparison of conventional imaging with helical CT.

PURPOSE: To assess helical computed tomography (CT) as a potential substitute for intravenous urography and renal angiography in the evaluation of living potential renal donors. MATERIALS AND METHODS: Helical CT was performed in 32 potential donors both before and after administration of contrast material. Scans were reconstructed at 1.5-mm intervals for three-dimensional reconstructions. Helical CT images were blindly compared with urograms (n = 32) and renal angiograms (n = 24). RESULTS: One small accessory artery was not depicted with helical CT, and angiography did not depict an accessory artery arising in proximity to the origin of the main renal artery. All eight kidneys with early dividing main arteries were identified with both helical CT and angiography. Three renal venous anomalies were depicted only with helical CT. Helical CT and urography equally depicted nonvascular findings. CONCLUSION: Renal helical CT is a suitable replacement for intravenous urography and angiography in the assessment of living renal donors.

Adult↗
PubMed1994

Long-term assessment of renal function following nephrectomy for stage I renal carcinoma.

OBJECTIVE: To evaluate the impact of nephrectomy on renal function in people who are potential candidates for nephron sparing surgery, i.e. partial nephrectomy. PATIENTS AND METHODS: A retrospective analysis was carried out of 109 patients (35 women, 74 men) who had undergone a nephrectomy for stage I renal carcinoma at the University of Michigan between 1960 and 1979. All patients had a functioning contralateral kidney and had undergone at least one post-operative serum creatinine evaluation. Statistical analysis was by Pearson's correlation coefficient. RESULTS: One individual developed a transitional cell carcinoma in the remaining renal pelvis and was treated with nephroureterectomy. No other patient progressed to dialysis. Five patients had post-operative serum creatinine levels from 221 to 354 mumol/l, one of whom had undergone both a nephrectomy and a partial nephrectomy for bilateral renal tumours. The remaining four had renal disease including diabetes, hypertension, pyelonephritis and renal artery stenosis. There was a strong association between pre-operative and post-operative serum creatinine values. CONCLUSION: Patients with low stage renal tumours and a normal contralateral kidney are at low risk of progression to renal failure.

Aged↗
PubMed1993

Vesicopyeloplasty in renal transplant patients: a 20-year followup.

Loss of a ureter in a renal transplant patient often results in transplant nephrectomy. In 1973 we used vesicopyelostomy with the bladder directly sutured to the renal pelvis as a method of reconstruction in 2 renal transplant patients following ureteral loss. These patients have been followed for more than 20 years and both renal allografts have functioned well. The status of these patients and a review of the literature on vesicopyelostomy are presented.

Adult↗
PubMed1993

Treatment of renal transplant ureteral complications by percutaneous techniques.

From January 1985 to October 1990, 487 adult renal transplantations were performed at our institution. Of 16 ureteral complications noted 15 were initially managed with percutaneous nephrostomy. Of the 8 complications that occurred during the last 2 years 5 resolved on percutaneous nephrostomy and stenting, or stenting with dilation alone. We conclude that percutaneous nephrostomy is indicated as an initial step in the diagnosis and treatment of urological transplant complications, and that it allows for nonoperative resolution of many of these complications.

Adult↗
PubMed1993

Results of combined Nesbit penile plication with plaque incision and placement of Dacron patch in patients with severe Peyronie's disease.

We treated 9 men with severe curvature of the penis secondary to Peyronie's disease with penile plication and a previously unreported technique of incision of the Peyronie plaque and placement of Dacron patch. All men were potent before penile straightening. At a mean followup of 17.5 months all men achieved good to excellent correction of the deformity and they have remained potent. One patient initially complained of numbness of the glans penis and decreased penile rigidity distal to the Dacron patch but potency returned and the numbness resolved.

Adult↗
PubMed1992

Ureteroscopic treatment of urothelial carcinoma of the ureter and renal pelvis.

From June 1987 to September 1990, 12 patients were evaluated for ureteroscopic treatment of upper urinary tract neoplasms. Four patients were not considered candidates because of technical reasons. Each of these patients was treated by nephroureterectomy. A total of 8 patients underwent ureteroscopic therapy with a neodymium:YAG laser 1 to 11 times (median 2) for the treatment of 3 proximal ureteral or pelvic lesions and 7 distal ureteral lesions. One patient had local progression and 1 failed subsequent laser treatment for technical reasons. Both of these individuals were salvaged with an operation. Three patients were without recurrence for 15, 21 and 36 months. Two patients had multiple superficial local recurrences and continue to be managed endoscopically without local progression for 12 and 32 months. One patient was asymptomatic 16 months after treatment but he has refused followup evaluation. Of 7 patients with ureteral tumors who were believed to be candidates for endoscopic therapy 5 have had the tumors controlled by this method of treatment. Only 1 renal pelvic tumor has been successfully treated. Most patients with tumors in the renal pelvis are not candidates for rigid endoscopic therapy because of the tumor size and location. In selected individuals ureteroscopic laser treatment of upper urinary tract transitional cell carcinoma can achieve local control with renal preservation.

Aged↗
PubMed1991

Results of 1,469 microsurgical vasectomy reversals by the Vasovasostomy Study Group.

During a 9-year period 1,469 men who underwent microsurgical vasectomy reversal procedures were studied at 5 institutions. Of 1,247 men who had first-time procedures sperm were present in the semen in 865 of 1,012 men (86%) who had postoperative semen analyses, and pregnancy occurred in 421 of 810 couples (52%) for whom information regarding conception was available. Rates of patency (return of sperm to the semen) and pregnancy varied depending on the interval from the vasectomy until its reversal. If the interval had been less than 3 years patency was 97% and pregnancy 76%, 3 to 8 years 88% and 53%, 9 to 14 years 79% and 44% and 15 years or more 71% and 30%. The patency and pregnancy rates were no better after 2-layer microsurgical vasovasostomy than after modified 1-layer microsurgical procedures and they were statistically the same for all patients regardless of the surgeon. When sperm were absent from the intraoperative vas fluid bilaterally and the patient underwent bilateral vasovasostomy rather than vasoepididymostomy, patency occurred in 50 of 83 patients (60%) and pregnancy in 20 of 65 couples (31%). Neither presence nor absence of a sperm granuloma at the vasectomy site nor type of anesthesia affected results. Repeat microsurgical reversal procedures were less successful. A total of 222 repeat operations produced patency in 150 of 199 patients (75%) who had semen analyses and pregnancy was reported in 52 of 120 couples (43%).

Adult↗
PubMed1989

Transrectal ultrasound. A case report related to the natural history of prostate cancer.

This is a case report of a man with prostate cancer diagnosed 10 years ago by digital rectal examination and prostatic biopsy. He was followed with serial transrectal ultrasound examinations for the last 22 months. Transrectal ultrasound enabled us to observe the natural history of his cancer. Because of accelerated tumor growth, a radical prostatectomy was performed. The tumor was confined within the prostate capsule and thus considered a "cure." Transrectal ultrasound is an invaluable tool for continuous monitoring of patients with prostate cancer.

Adenocarcinoma↗
PubMed1989

Diagnostic value of routine bone scintigraphy renal imaging in renal cell carcinoma.

Technetium-99m-phosphate compounds used in bone scanning are excreted by the kidney, and excellent renal images can be obtained on routine bone scintigrams. The preoperative bone scans of 49 patients who underwent radical nephrectomy for renal cell carcinoma between 1981 and 1985 were reviewed for renal imaging. Ninety-four percent of the patients had abnormal bone scan renal images (82% had focal decreased uptake, and 12% had focal increased uptake). Six percent of the renal images were symmetrical bilaterally. When bone scans are employed in the postoperative follow-up of patients with renal cancer, they can be used to assess the status of the remaining kidney.

Adult↗
PubMed1989

Microsurgical penile revascularization using the central corporeal penile artery.

We treated 9 patients with vasculogenic impotence by penile revascularization using a microsurgical anastomosis between the inferior epigastric artery and the central corporeal penile artery. Diagnostic evaluation included penile brachial indexes and pelvic arteriograms, which were abnormal in all 9 patients. Revascularization was technically possible in 7 of 9 patients; 2 had inadequate central arteries. The penile brachial index initially was improved in all 7 patients, although 1 had an early occlusion at 2 months and 1 had a late occlusion at 4 years. Potency was improved initially in 6 of the 9 patients, with longer term improvement in 5 of 9 followed 1 to 8 years. Two patients remain potent currently. The advantages of this technique are a reasonably high technical success rate in selected patients, with improved initial potency in more than half. The disadvantages include technical difficulty, lack of clear-cut selection criteria and unknown long-term results.

Adult↗
PubMed1989

Management of rectal injuries during radical cystectomy.

We reviewed the incidence and management of intraoperative rectal injuries in patients who underwent radical cystectomy from January 1980 through July 1988 to assess the role of primary repair without diverting colostomy as definitive therapy. During this interval 163 radical cystectomies were performed and 125 charts were available for review. The incidence of rectal injuries was 9.6% (12 of 125 patients). The rate of rectal injury in patients who had previously received definitive pelvic radiation was 27% (3 of 11). The incidence of injury in patients who received 2,000 rad preoperative radiation (11%, 2 of 17) was similar to that noted in individuals who were not irradiated (7%, 7 of 97). Of the 12 patients with rectal injury 9 underwent primary closure without diverting colostomy. The remainder were treated with an initial colostomy. Only 1 patient who had not received prior radiation required a colostomy after initial treatment with primary closure. The 8 successful primary rectal closures were done in 2 patients who underwent definitive pelvic radiation, 2 who had received 2,000 rad preoperatively and 4 who had not been irradiated.

Aged↗
PubMed1988

Is radical cystectomy indicated in patients with regional lymphatic metastases?

The records of 21 patients who had radical cystectomies for the treatment of locally advanced bladder cancer and were found to have regional lymphatic metastases have been reviewed. Ten of these patients had only one lymph node involved (N1), and 11 patients had metastases in more than one lymph node (N2-3). Four patients with N1 disease and 1 patient with N2-3 disease survived tumor-free greater than forty months postoperatively. Radical cystectomy can produce long-term disease-free survival in some patients with limited pelvic metastases.

Aged↗
PubMed1988

Extravesical ureteroneocystostomy in renal transplantation.

From October 1970 to January 1986, 808 patients underwent renal transplant ureteroneocystostomy by an extravesical technique. Complications related to the anastomosis and/or ureter were reviewed. There were 23 total complications, for an over-all urological complication rate of 2.8 per cent. Of these complications 17 were related to the ureteroneocystostomy, for an anastomotic complication rate of 2.1 per cent. Complications were almost universally repaired by another operation. Two patients died and 1 lost the allograft because of urological complications.

Anastomosis, Surgical↗