Dorothea Rohrmann

Alloplastic Replacement of the Urinary Bladder

PURPOSE The loss of a functioning bladder is nowadays mostly managed by replacement with gastrointestinal segments. Management of these urinary diversions is difficult and the long-term effects are unknown. We developed a silicone rubber prosthesis for alloplastic replacement of the urinary bladder and tested it in an animal experiment. MATERIAL AND METHODS Two artificial bladders were implanted into subcutaneous pockets on each side of the anterior abdominal wall. Cystectomy was performed and each prosthesis was connected to one kidney. Distally, a Y-shaped tube sutured to the urethral stump joined the two bladder outlets. The whole system was successfully implanted in 5 sheep with a mean follow-up of 11.5 months (5-19 months). RESULTS Adequate capacity, effective and reliable mechanical function and patent anastomoses to the renal pelvis and the urethra could be achieved. Blood chemistry and renal ultrasound were performed at regular intervals demonstrating neither morphological nor functional deterioration of the renal parenchyma. Histopathological examination in the end of the experiment confirmed the excellent clinical results. CONCLUSIONS The positive outcome of these animal experiments suggests this system would be useful for human bladder substitution. Standardized industrial production of the prostheses will be needed prior to implantation in humans.

Protective Effect of Tadenan of Bladder Function Secondary to Partial Outlet Obstruction

PURPOSE Tadenan (DEBAT, Paris, France) is a pharmaceutical agent used in the treatment of benign prostatic hyperplasia (BPH). The specific aim of this study was to determine if pretreatment of rabbits with Tadenan reduced either the hypertrophic response of the bladder to partial outlet obstruction or the accompanying contractile dysfunction. MATERIALS AND METHODS Twenty-five male New Zealand rabbits (3 to 5 kg.) were separated into 5 groups of 5 rabbits each. Each rabbit in groups 1,2, and 3 received Tadenan orally at 1, 10 and 100 mg./kg./day for 3 weeks. Group 4 received vehicle only (peanut oil); Group 5 were controls. The bladders were evaluated (in vitro studies) after 2 weeks of obstruction. RESULTS 1) Tadenan did not reduce the effect of partial outlet obstruction on bladder mass. 2) Tadenan pretreatment resulted in a significant protective effect on the contractile responses to field stimulation, bethanechol and KCl. CONCLUSIONS These results clearly demonstrate that Tadenan pretreatment protected the bladder from the contractile dysfunctions induced by partial outlet obstruction.

MAGNETIC RESONANCE UROGRAPHY IN CHILDREN: EVALUATION OF SUSPECTED URETERAL ECTOPIA IN DUPLEX SYSTEMS

PURPOSE We evaluate the diagnostic accuracy of magnetic resonance urography in children with suspected ectopic ureters and ureteroceles in duplex systems. MATERIALS AND METHODS A total of 14 children 4 weeks to 8 years old with a total of 18 duplex systems underwent magnetic resonance urography using a 1.5 tesla scanner. After injection of low dose furosemide, half-Fourier rapid acquisition with relaxation enhancement images were obtained for T2-weighted static fluid magnetic resonance urography. Respiratory gated 3-dimensional gradient echo images were acquired for T1-weighted excretory magnetic resonance urography 5 to 30 minutes after intravenously administered gadolinium. RESULTS All magnetic resonance examinations were successfully performed without sedation. The diagnostic accuracy of T1-weighted excretory magnetic resonance urography depended on the renal function. Twelve duplex systems with a normal excretory function, including 6 bifid ureters and 6 upper moieties with inferomedial ectopic ureters, were analyzed correctly with the exception of a 6 mm. ureterocele in 1 case. In 6 duplex systems with poor or nonfunctioning upper moieties ectopic ureters were only demonstrated on T2-weighted magnetic resonance urograms. CONCLUSIONS Respiratory gated excretory and static fluid magnetic resonance urography complement each other in the evaluation of duplex systems in children and provide high accuracy in the evaluation of suspected ectopic ureters and ureteroceles.

Feasibility and utility of respiratory-gated, gadolinium-enhanced T1-weighted magnetic resonance urography in children.

RATIONALE AND OBJECTIVES To evaluate the feasibility and utility of respiratory-gated, gadolinium-enhanced T1-weighted magnetic resonance (MR) urography in children. METHODS In a prospective study, 30 consecutive children, aged 3 weeks to 13.8 years, underwent MR urography. After intravenous injection of low-dose furosemide and gadopentetate dimeglumine, respiratory-gated, coronal, T1-weighted 3D-gradient-echo sequences were obtained at 1.5 T 5 to 30 minutes after contrast administration. Postprocessing of the data was performed using a maximum-intensity projection algorithm. In addition, precontrast half-Fourier rapid acquisition with relaxation enhancement MR urograms were obtained in 29 children. RESULTS Respiratory-gated, T1-weighted MR urography was successfully performed in all children without the need for sedation. Compared with the final diagnosis, prospective analysis of MR urography images revealed the correct diagnosis in 56 of 58 pelvicaliceal systems (96%). The ureteral morphology was correctly evaluated in 59 of 64 ureters (92%). The method showed limited efficiency for evaluating nonfunctioning renal units. CONCLUSIONS Respiratory-gated, gadolinium-enhanced T1-weighted MR urography is a feasible and effective diagnostic tool in the assessment of upper urinary tract morphology in children. It is especially useful in depicting nondilated collecting systems and ureters.

Different Types of Scaffolds for Reconstruction of the Urinary Tract by Tissue Engineering

Introduction: Tissue engineering is an important and expanding field in reconstructive surgery. The ideal biomaterial for urologic tissue engineering should be biodegradable and support autologous cell growth. We examined different scaffolds to select the ideal material for the reconstruction of the bladder wall by tissue engineering. Materials and Methods: We seeded mouse fibroblasts and human keratinocytes in a co-culture model on 13 different scaffolds. The cell-seeded scaffolds were fixed and processed for electron microscopy, hematoxylin and eosin stain, and immunohistochemistry. Cell density and epithelial cell layers were evaluated utilizing a computer-assisted optical measurement system. Results: Depending on the growth pattern, scaffolds were classified into the following three distinct scaffold types: carrier-type scaffolds with very small pore sizes and no ingrowth of the cells. This scaffold type induces a well-differentiated epithelium. Fleece-type scaffolds with fibers and huge pores. We found cellular growth inside the scaffold but no epithelium on top of it. Sponge-type scaffolds with pores between 20 and 40 µm. Cellular growth was observed inside the scaffold and well-differentiated epithelium on top of it. Conclusion: To our knowledge, this is the first time three distinct scaffold types have been reported. All types supported the cell growth. The structure of the scaffolds affects the pattern of cell growth.

Bladder wall replacement by tissue engineering and autologous keratinocytes in minipigs

To develop a tissue‐engineered bladder wall replacement with autologous cells and a biodegradable scaffold, as whenever there is a lack of native urological tissue the bladder is reconstructed with different bowel segments, which has inevitable complications.

A Continent Urinary Diversion in a Female With Agenesis of the Bladder: A 5-Year Follow-up

There are few case reports of bladder agenesis. The outcome of the patients differs and depends on the associated malformations. Different urinary diversions are described to save renal function. Most of the surviving patients with bladder agenesis have undergone incontinent urinary diversions as primary treatment. We describe the case of a female infant with agenesis of the bladder that arrived in our institution after several septic episodes. Treatment of choice was a continent pouch with an appendicovesicostomy. We state that even in young children, a primary continent urinary diversion can be performed with excellent long-term outcome.

Chronic Subdural Hematoma Associated with Voiding Dysfunction

We report the case of a 73-year-old male who presented with a chronic subdural hematoma that compressed the frontal lobe, an area known to be active in detrusor control, and caused contralateral hemiparesis and urgency incontinence. Urodynamically, he had a small bladder capacity and high amplitude overactive detrusor contractions with an intact sphincteric response. We concluded that the effect of intracranial lesions on voiding depends upon the site rather than the type of the pathology. Further in-depth studies are needed to clarify the effect of intracranial lesions, and accordingly the function of different brain regions and their influence on voiding.

Microangiopathy and mild mixed neuromyopathic alterations in a patient with homozygous PIEZO-2 mutation

We report a 9-year-old girl homozygous for a loss-of-function mutation in the PIEZO-2 gene. She showed generalized muscular hypotonia with severe scoliosis, joint deformities, deficient proprioceptive function and selective atrophy and signal alterations of both gastrocnemii on whole body MRI scan. Light microscopic and ultrastructural examination showed few atrophic fibres, abnormal mitochondria, focal myofibrillar disruption and endomysial capillary microangiopathy.

Voiding Dysfunction due to Chronic Viral Encephalitis in a Young Woman

We record a case of a 37-year-old female with acute viral encephalitis, frequency and urgency incontinence. Video urodynamics showed small bladder capacity, sensory urgency, high residual urine and a Christmas tree appearance of the bladder. MRI showed inflammation and edema in the area of the thalamus and internal capsule in the early stage, then cavitation and gliosis in the same regions in the late stage.