M. Hohenfellner

The Nutcracker Syndrome: New Aspects of Pathophysiology, Diagnosis and Treatment

Magnetic resonance imaging (MRI) was used to study vascular anatomy in 3 patients with the nutcracker syndrome and in 10 healthy volunteers. From these studies an abnormal branching of the superior mesenteric artery from the aorta was identified as being the cause of the nutcracker syndrome. Consequently, surgical transposition of the left renal vein to achieve an unobstructed renal venous backflow was performed successfully in 2 patients, while 1 underwent nephrectomy. In 1 patient adjuvant ureteral instrumentation became necessary to aid occlusion of persisting shunts between peripelvic venous varicosities and the urinary tract. Awareness of the pathophysiology of the nutcracker syndrome ensures an early diagnosis, which should be confirmed by a combination of diagnostic procedures, including MRI.

Chronic sacral spinal nerve stimulation for fecal incontinence: Long-term results with foramen and cuff electrodes

PURPOSE: Sacral spinal nerve stimulation is a new therapeutic approach for patients with severe fecal incontinence owing to functional deficits of the external anal sphincter. It aims to use the morphologically intact anatomy to recruit residual function. This study evaluates the long-term results of the first patients treated with this novel approach applying two techniques of sacral spinal nerve stimulator implantation. METHODS: Six patients underwent either of two techniques for electrode placement: one “closed” (electrodes placed through the sacral foramen) and one “open” (cuff electrodes placed after sacral laminectomy). Follow-up evaluation of their continence status ranged from 5 to 66 months. RESULTS: Incontinence improved in all patients. The percentage of incontinent bowel movements decreased during chronic stimulation from a mean of 40.2 percent to 2.8 percent, and the Wexner score decreased from a mean of 17 to 2. The function of the striated anal sphincter improved during chronic stimulation: maximum squeeze pressure increased from a mean of 48.5 mmHg to 92.7 mmHg, and median squeeze pressure increased from a mean of 37.3 mmHg to 72.5 mmHg. No complications were encountered perioperatively or postoperatively. Two devices had to be removed because of intractable pain, in one patient at the site of the electrode after five months and in the other at the site of the impulse generator after 45 months. CONCLUSION: Long-term sacral spinal nerve stimulation persistently improves continence and increases striated anal sphincter function in patients with fecal incontinence owing to functional deficits, but in whom the striated anal sphincter is morphologically intact. Two different operative approaches can be applied effectively.

Bilateral sacral spinal nerve stimulation for fecal incontinence after low anterior rectum resection

AbstractBackground and aims. The somatomotor innervation pattern has been shown to differ in patients undergoing percutaneous nerve evaluation for sacral nerve stimulation. In some patients bilateral stimulation might improve clinical outcome; however, only single-channel pulse generators have until now been available. We report a patient with fecal incontinence after surgery for rectal carcinoma in whom a dual-channel, individually programmable, pulse generator permitted implantation of neurostimulation electrodes bilaterally. Patients and methods. Intractable fecal incontinence developed in a 48-year-old man who underwent low anterior rectum resection, owing mainly to reduced internal anal sphincter function. The morphology of the anal sphincter was without defect. Based on the findings of unilateral and bilateral temporary sacral nerve stimulation the patient underwent placement of foramen electrodes on S4 bilaterally. Both electrodes were connected to a dual-channel impulse generator for permanent low-frequency stimulation. Results. The percentage of incontinent bowel movements decreased during unilateral test stimulation from 37% to 11%, during bilateral test stimulation to 4%, and with chronic bilateral stimulation to 0%. The Wexner continence score improved from 17 preoperatively to 2, and quality of life (ASCRS score) was notably enhanced. Anorectal manometry revealed improved striated anal sphincter function; the internal anal sphincter remained unaffected. Conclusion. Sacral nerve stimulation can effectively treat incontinence after rectal resection, and bilateral stimulation can improve the therapeutic effect.

Orthotopic bladder substitution in women: functional evaluation.

PURPOSE Orthotopic bladder substitution following cystectomy in women has recently been introduced at some specialized centers. Studies of such a procedure should consider the oncological and functional outcomes. We analyzed only the functional results of orthotopic bladder substitution since followup is too short (about 2 years) for a valid oncological assessment. MATERIALS AND METHODS From October 1994 to November 1997, 60 women with a mean age of 48.3 years underwent standard radical cystectomy and orthotopic diversion (ileal W-neobladder with subserous tunnel in 47 and hemi-Kock reservoir in 13). The oncological criterion was organ confined invasive bladder cancer. RESULTS There was no perioperative mortality. Postoperative complications included fatal pulmonary embolism in 1 woman, deep vein thrombosis in 2, prolonged ileus in 1 and fistula of the vaginal pouch in 3, which was repaired successfully. Cancer recurred in the pelvis in 2 cases and as distant metastases in 5. Of the patients 43 had been followed for a mean of 20.2 months (range 6 to 36), and 32 were continent day and night, 1 was totally incontinent, 2 had daytime stress incontinence and 6 had nighttime incontinence. Six women had difficulty emptying the pouch spontaneously with concomitant residual urine due to acute angulation between the urethra and pouch. CONCLUSIONS Orthotopic bladder substitution after standard radical cystectomy in select women provides a satisfactory functional outcome. Failure of complete emptying seems to be due to anatomical rather than functional reasons.

Transposition of the left renal vein for treatment of the nutcracker phenomenon: long-term follow-up

OBJECTIVES To assess the therapeutic value of left renal vein transposition for treatment of the nutcracker phenomenon in long-term follow-up. METHODS Eight patients (4 women and 4 men) between 23 and 58 years old (mean 39.1) underwent transposition of the left renal vein for treatment of the nutcracker phenomenon associated with recurrent gross hematuria and flank pain. The postoperative follow-up was 41 to 136 months (mean 66.4). RESULTS No perioperative complications were encountered. The postoperative complications comprised deep vein thrombosis (n = 1), retroperitoneal hematoma necessitating surgical revision (n = 1), and paralytic ileus that resolved with conservative management (n = 1). One patient underwent laparotomy for treatment of mechanical ileus due to adhesions 4 years after the initial surgery. In 7 of 8 patients, transposition of the left renal vein efficiently relieved the symptoms related to the nutcracker phenomenon. In 1 patient, the hematuria persisted despite postoperative normalization of the pressure gradient between the left renal vein and the inferior vena cava. CONCLUSIONS Transposition of the left renal vein is an efficient surgical approach for the treatment of the nutcracker phenomenon and is associated with an acceptable risk of complications. However, rare cases may be encountered in which the shunted connections between the renal veins and the collecting system are so matured that, despite removal of the obstruction of the renal venous backflow, gross hematuria may persist.

Chronic sacral neuromodulation for treatment of neurogenic bladder dysfunction: long-term results with unilateral implants

OBJECTIVES To investigate the therapeutic value of sacral neuromodulation in patients with neurogenic disorders in whom conservative treatment options were unsuccessful. Neurogenic disorders may result in various forms of lower urinary tract dysfunction. METHODS Twenty-seven patients (19 women, 8 men) aged 18 to 63 years (mean 44.9 years) were subjected to percutaneous test stimulation of the sacral spinal nerves. Their urologic symptoms consisted of bladder storage failure (n = 15) due to detrusor hyperreflexia and/or bladder hypersensitivity, failure to empty due to detrusor areflexia (n = 11), and combined bladder hypersensitivity and detrusor areflexia (n = 1). Twelve patients (11 women and 1 man) underwent chronic sacral neuromodulation with unilateral electrode implantation into one of the dorsal S3 foramina. The follow-up was 89.3 months (range 13 to 126). RESULTS Severe side effects were encountered in 2 patients (1 with infection and 1 with adverse sensation during stimulation) and moderate side effects in another 3 patients. In 1 patient, the implant had to be removed during the immediate postoperative period. In 3 patients, the implant was not effective. In 8 patients, the symptoms of lower urinary tract dysfunction were significantly attenuated (50% or more) for 54 months (range 11 to 96). After this period, all implants became ineffective, except one, which was still in use at the last follow-up visit. CONCLUSIONS Unilateral chronic sacral neuromodulation using sacral foramen electrodes can be a valuable, but only temporary, treatment for neurogenic bladder dysfunction. The technique of chronic sacral neuromodulation should be refined to achieve the same and lasting results with implantation systems as achieved with preoperative test stimulation.

Tumor in the Horseshoe Kidney: Clinical Implications and Review of Embryogenesis

We report on 3 patients with tumor in a horseshoe kidney, 1 of whom had bilateral tumor (renal cell cancer on the right side and urothelial cancer on the left side). Tumors that arise predominantly in the bridge of a horseshoe kidney can mimic the symptoms of an intra-abdominal disease process. Besides routine diagnostic procedures, angiography is essential to plan the surgical approach, which in principle should be organ-sparing. The literature of the embryology of the horseshoe kidney was reviewed for a relationship between the abnormal renal development and the site of tumorigenesis, and for development of a key for the wide variation of blood supply. Recently reported data suggest that the theory of a mechanical fusion is valid only for horseshoe kidneys with a fibrous isthmus but that an abnormal migration of the posterior nephrogenic area causes the majority of horseshoe kidneys in which the isthmus consists of parenchyma. Development of the isthmus through abnormal migration could predispose this location for renal cell cancer and would explain the varying forms of blood supply. Additionally, this hypothesis supports the previously raised assumption that horseshoe kidneys may be the result of teratogenic factors, which also may be responsible for the known increased incidence of related congenital anomalies and of nephroblastoma.

Sacral bladder denervation for treatment of detrusor hyperreflexia and autonomic dysreflexia.

OBJECTIVES Detrusor hyperreflexia after spinal cord injury may cause urinary incontinence and chronic renal failure. In patients refractory to conservative treatment and not eligible for ventral sacral root stimulation for electrically induced micturition, we investigated the therapeutic value of sacral bladder denervation as a stand-alone procedure. METHODS Nine patients (8 men and 1 woman) between 21 and 58 years old (mean 30.2) with traumatic suprasacral spinal cord lesions underwent sacral bladder denervation for treatment of detrusor hyperreflexia and/or autonomic dysreflexia. RESULTS Detrusor hyperreflexia and autonomic dysreflexia were eliminated in all cases. Bladder capacity increased from 177.8 +/- 39.6 to 668.9 +/- 64.3 mL; intravesical pressure decreased from 89.3 +/- 19.1 to 20.2 +/- 2.7 cm H(2)O. For facilitating clean intermittent catheterization (CIC), 4 patients received a continent vesicostomy in a second-stage procedure; one of them in combination with bladder augmentation. Four patients empty their bladder by way of urethral CIC. One completely tetraplegic patient has an indwelling urethral catheter. In the 5 patients with autonomic dysreflexia, the systolic blood pressure was lowered from 196 +/- 16.9 to 124 +/- 9.3 mm Hg and the diastolic blood pressure from 114 +/- 5.1 to 76 +/- 5.1. The annual frequency of urinary tract infections decreased from 9 +/- 1.2 to 1.8 +/- 0.7. In all patients, renal function remained stable. CONCLUSIONS In selected patients with detrusor hyperreflexia and/or autonomic dysreflexia, sacral bladder denervation is a valuable treatment option. It is only moderately invasive in nature, requires neither sophisticated nor expensive medical equipment, and is an attractive alternative to urinary diversion using intestinal segments.

Sacral neuromodulation for treatment of lower urinary tract dysfunction

Despite initial reservations, sacral neuromodulation has begun to develop as a new therapeutic tool for the treatment of lower urinary tract dysfunction. It bridges the gap between conservative treatment options and highly invasive procedures, such as urinary diversion. At present, there are no clinical variables that can reliably predict the efficacy of neuromodulation in an individual patient. All patients, regardless of indication, must therefore undergo a test stimulation before they can be offered chronic sacral neuromodulation with an implanted system. Evaluations in various clinical trials have confirmed that sacral neuromodulation, based on unilateral sacral foramen electrode implantation, has statistically significant therapeutic effects compared to controls, in patients with urge syndromes and failure to empty. The patients most likely to benefit from this treatment are those with detrusor hyperactivity or detrusor hypo‐activity. Those with pain syndromes are less likely to respond and to benefit from treatment. Acute and subchronic sacral neuromodulation are associated with very low rates of complications. Complications of chronic sacral neuromodulation are caused either by surgery‐related morbidity or hardware problems. Conservative treatment options should be exhausted before neuromodulation is considered. This rule has two purposes: First, it postpones surgery, with its potential morbidity, for as long as possible; second, the long‐term efficacy of neuromodulation is still unclear and may be limited in some patients. A fully exploited conservative therapy, in combination with subsequent sacral neuromodulation, may therefore be the optimum way to pursue therapeutic options of relatively low invasiveness.

RETROVESICAL MASS IN MEN: PITFALLS OF DIFFERENTIAL DIAGNOSIS

PURPOSE We review the differential diagnosis and treatment of retrovesical masses in men. MATERIALS AND METHODS During the last 8 years 21 male patients 3 to 79 years old (mean age 47.1) presented with symptoms or signs of a retrovesical mass. Clinical features and diagnostic findings were reviewed, and related to surgical and histopathological findings. RESULTS The retrovesical masses included prostatic utricle cyst in 3 cases, prostatic abscess in 1, seminal vesicle hydrops in 6, seminal vesicle cyst in 2, seminal vesicle empyema in 3, large ectopic ureterocele in 1, myxoid liposarcoma in 1, malignant fibrous histiocytoma in 1, fibrous fossa obturatoria cyst in 1, hemangiopericytoma in 1 and leiomyosarcoma in 1. In 17 patients various symptoms were seen and in 4 the mass was incidentally detected. A mass was palpable on digital rectal examination in 16 cases and visible on sonography in 20. For a cystic mass medial location relative to the bladder neck was suggestive of prostatic abscess or utricle cyst, while lateral location was suggestive of seminal vesicle cyst/hydrops or empyema, ectopic ureter or ureterocele. In 6 patients diagnosis was established only by exploratory laparotomy and histopathological examination. CONCLUSIONS Digital rectal examination and sonography reliably detect a retrovesical mass. Nevertheless, clinical signs and median or lateral location relative to the bladder neck on ultrasound are diagnostic only for cystic lesions. Computerized tomography and magnetic resonance imaging are useful for staging malignant tumors. However, needle or open biopsy is required in most cases to establish a histopathological diagnosis. Exploratory laparotomy and histopathological examination are the procedures of choice when other findings are equivocal.