Biomedical subjects

D Bägli

Publications and source records attributed to D Bägli.

8 recordsLinked to original sources

PubMed2003

Healing of unstented tubularized incised plate urethroplasty: an experimental study in a rabbit model.

OBJECTIVE: To develop a rabbit model to study the temporal healing taking place after an unstented tubularized incised plate urethroplasty (TIPU). MATERIALS AND METHODS: The study comprised 13 New Zealand white rabbits (3-4 kg); the ventral wall of the penile urethra was excised to create a hypospadias-like defect. A vertical incision was made in the dorsal urethral plate and the incised urethra tubularized. Two animals were killed at 2 days and two at 5 days after surgery, and the remainder killed at 2, 6 and 12 weeks (three each). A retrograde urethrogram was taken at autopsy. Serial sections of the penis were stained with haematoxylin and eosin, and Masson trichrome for microscopy. RESULTS: There were no deaths related to the procedure and all animals voided spontaneously. Retrograde urethrograms showed no fistulae or stricture. Microscopic examination at 2 and 5 days showed partial coverage of the incision with regenerating urothelium. At 2 weeks there was full-thickness urothelium with a mild inflammatory reaction. At 6 and 12 weeks, remodelling of the peri-urethral connective tissue with minimal fibrosis completed the healing. CONCLUSION: The mechanism of healing of the incised urethral plate involves normal urothelial regeneration into the depth of the incised defect, which explains the gain in urethral diameter after TIPU. Urine flow, during normal voiding, might be responsible for keeping the incised plate open during urothelial regeneration. A urethral stent was not necessary for normal healing in this model.

Animals↗

PubMed2002

A single-centre long-term outcome analysis of artificial urinary sphincter placement in children.

OBJECTIVE: To retrospectively evaluate the outcome of artificial urinary sphincter (AUS) placement in 79 children, with a mean follow-up of 12.5 years. PATIENTS AND METHODS: A total of 89 children had an AUS placed between 1977 and 1994; complete data were obtained for 79 (63 boys and 16 girls). The indication for AUS placement was urinary incontinence caused by sphincteric deficiency with a stable bladder. Before and after surgery, all patients underwent ultrasonography, voiding cysto-urethrography and urodynamics. Logistic regression was used to assess the factors influencing the outcome. RESULTS: The mean (range) age at surgery was 11.7 (3-18) years. The cause of incontinence was a neuropathic bladder in 74 patients and bladder exstrophy in five. At a mean (range) follow-up of 12.5 (5-22) years, 63 of 79 patients (80%) had an intact AUS. The AUS was removed in 16 patients (20%) because of erosion at a mean (range) of 5.6 (1-11) years after insertion; there were 0.035 revisions per patient-year. Of 63 patients with an AUS in place, 57 (90%) are completely dry and 36 (57%) are using clean intermittent catheterization. Thirteen patients (20%) developed bladder instability during the follow-up, which was managed by anticholinergics in eight, spinal cord de-tethering in three and enterocystoplasty in two. Hydronephrosis occurred in 12 of 126 renal units (10%) that improved after enterocystoplasty or anticholinergics. The overall 10-year survival of the AUS was 79% (78% for early models and 80% for the AMS800); the survival was not affected by age, sex, model, previous bladder neck surgery, augmentation cystoplasty or intermittent catheterization. Bladder exstrophy was associated with lower AUS survival, as four of the five patients affected had the AUS removed secondary to erosion (P = 0.014). CONCLUSION: In children the AUS has a 79% 10-year survival and gives a 90% continence rate. Bladder instability after AUS placement can be managed with anticholinergics or enterocystoplasty. The AUS is not a justifiable treatment option for patients with bladder exstrophy.

Adolescent↗

PubMed2000

Outcomes of primary valve ablation versus urinary tract diversion in patients with posterior urethral valves.

OBJECTIVES: Although valve ablation is the treatment of choice for patients with posterior urethral valves, debate continues as to the role of urinary diversion. We sought to retrospectively compare the clinical and radiologic outcomes between valve ablation and urinary diversion for patients with posterior urethral valves. METHODS: We retrospectively reviewed the records of 50 consecutive patients with posterior urethral valves since January 1995. On the basis of the initial renal function and radiologic findings, patients were divided into three groups: group 1, normal renal function and radiologically normal upper tracts; group 2, normal renal function with hydronephrosis and/or reflux; and group 3, azotemia with hydronephrosis or reflux. RESULTS: All 22 patients in group 1 were treated with valve ablation. After a mean follow-up of 32 months, these children had normal renal function and no evidence of upper tract deterioration. All 13 patients in group 2 were also treated with valve ablation. The radiologic abnormalities (hydronephrosis, reflux) resolved in 50% of cases, with an average follow-up of 28 months. Of the 15 patients in group 3, 7 underwent valve ablation and 8 underwent urinary diversion. Urinary diversion was performed in patients with renal deterioration and severe hydronephrosis and/or high-grade reflux. Renal function returned to normal in all patients who underwent valve ablation except one; renal function returned to normal in only 3 of 8 patients who underwent urinary diversion. Radiologically, the severity of the hydronephrosis and reflux was downgraded in patients who underwent valve ablation but not in the diverted group. CONCLUSIONS: Valve ablation is the mainstay of treatment for patients with posterior urethral valves. Prenatal and postnatal factors, such as renal dysplasia and urinary tract infection, respectively, rather than the posterior valve treatment dictate the long-term renal and radiologic outcomes.

Adolescent↗

PubMed2000

The natural history of neonatal vesicoureteral reflux associated with antenatal hydronephrosis.

PURPOSE: In an attempt to evaluate the natural history of neonatal vesicoureteral reflux, patients with antenatal history of hydronephrosis and documented reflux in the first 30 days of life were analyzed. MATERIALS AND METHODS: Between 1993 and 1998, 260 patients with a history of antenatal hydronephrosis were referred for evaluation. Of these patients 31 were diagnosed with unilateral or bilateral refluxing renal units (54 renal units). Patients were treated with a prospective plan of observational therapy and prophylactic antibiotics, and resolution rate was calculated in patients with adequate followup. Reflux grade was correlated with postnatal ultrasonographic findings, urinary tract infections and differential renal function. Outcome analysis of 34 high grade (III to V) refluxing renal units using the Kaplan-Meier survival curves was undertaken with the end point being complete resolution or improvement. Three patients with vesicostomy and 2 who underwent ureteral reimplantation were excluded from analysis. RESULTS: Reflux was grade I in 5% (33% males), II in 15% (62% males), III in 32% (71% males), IV in 18% (90% males) and V in 30% (100% males) of the patients. Postnatal ultrasound findings correlated poorly with the presence and degree of vesicoureteral reflux. Of 17 patients followed for at least 14 months (average followup 20) there was complete resolution in 60% with grade III, 50% with grade IV and 28% with grade V reflux. Using the Kaplan-Meier estimate there was a 50% chance of improvement (decrease in reflux grade by at least 2 grades) in high grade reflux by age 16 months. Urinary tract infections developed in 8 patients (26%) while on antibiotics. Of 46 renal units in 23 patients evaluated with a renal scan before urinary tract infection, 12 had less than 35% function. CONCLUSIONS: A normal postnatal ultrasound should not be a basis for excluding the use of cystography. Our Kaplan-Meier estimate shows that high grade reflux does improve and may resolve spontaneously. In addition, renal scarring may be seen with high and low grade reflux in the absence of urinary tract infection but high grade reflux is associated with a higher incidence of infection.

Female↗

PubMed2000

Lessons learned from laser tissue soldering and fibrin glue pyeloplasty in an in vivo porcine model.

PURPOSE: We compared sutured pyeloplasty to 2 newer techniques of tissue anastomosis, including laser soldered pyeloplasty using a diode laser with 50% albumin solder mixed with indocyanine green and fibrin glue. MATERIALS AND METHODS: We performed 53 pyeloplasties in 50 pigs using suture, laser or fibrin glue. In the immediate group anastomotic leak pressure was measured immediately postoperatively, and then animals were euthanized. At 1, 3 and 4 weeks postoperatively a pressure flow study at 10 cc per minute in cm. H2O was performed, and tissue was sent for histological and collagen content analysis. RESULTS: In the immediate studies laser soldering achieved a significantly higher mean anastomotic leak pressure (50.5 +/- 15.1 cm. H2O) than sutured (17.3 +/- 5.4) or fibrin glued (3.5 +/- 1.5) repairs. In the 1, 2 and 4-week studies animals in the sutured pyeloplasty group had no complications, and all pressure flow studies except 1 were normal. However, in the laser soldered groups we observed 8 urinomas in 19 animals, and most occurred during the first part of our study. This complication was prevented by stopping urine flow at the anastomotic site at laser irradiation and by improving application of the solder. Of the 11 animals in which pressure flow studies were performed only 2 were obstructed. Of the 7 chronic fibrin glue group 4 animals had urinomas and 2 had unobstructed pressure flow studies. Histological studies and immunohistochemical staining for collagen showed no differences in collagen distribution among the 3 procedures. CONCLUSIONS: Laser soldering and fibrin glue pyeloplasties are not superior in the long-term compared to sutured pyeloplasty. Fibrin glue in our animal model had the highest failure rate. Further improvements in the technical aspect of laser tissue welding need to be made to benefit from its theoretical advantages in minimally invasive surgery.

Anastomosis, Surgical↗

PubMed2000

The use of magnetic resonance imaging in the diagnosis and followup of pediatric pelvic rhabdomyosarcoma.

PURPOSE: Previous radiological descriptions of pelvic rhabdomyosarcoma emphasized ultrasonography and computerized tomography (CT). Few reports are available on the use of magnetic resonance imaging (MRI) for diagnosing and following pelvic rhabdomyosarcoma. We retrospectively compared MRI to CT for diagnosing and following children with pelvic rhabdomyosarcoma. MATERIALS AND METHODS: We treated 4 boys and 3 girls for pelvic rhabdomyosarcoma. Initial and followup evaluations included pelvic CT and MRI at intervals determined by treatment and disease status. We retrospectively reviewed the clinical charts and imaging studies of these patients. The initial radiological report was evaluated and then 1 radiologist reviewed all studies. Attention was directed toward identifying lesions revealed by CT or MRI but not by the other modality. RESULTS: MRI detected all lesions shown by CT. On the other hand, MRI detected residual disease in 1 case that was not demonstrated by CT. In 2 other patients MRI was superior to CT for delineating the local extent of disease, especially urethral involvement. CONCLUSIONS: Compared with CT, MRI improves the detection of residual pelvic rhabdomyosarcoma. Tissue planes are well delineated, allowing more accurate assessment of tumor invasion into adjacent structures. MRI is the imaging modality of choice for following pediatric patients with pelvic rhabdomyosarcoma.

Child↗

PubMed1999

Urinary retention after bilateral extravesical ureteral reimplantation: does dissection distal to the ureteral orifice have a role?

PURPOSE: We evaluated the outcome and incidence of urinary retention after bilateral detrusorrhaphy using 2 modifications of the original Lich-Gregoir procedure. MATERIALS AND METHODS: We evaluated the charts of 220 patients who underwent correction of bilateral vesicoureteral reflux using the extravesical approach from January 1991 to December 1997. Inverted Y detrusorrhaphy was performed in 154 patients and the advancing suture modification was done in 66. RESULTS: The success rate using the advancing suture technique was 92.4 and 95.4% at 3 and 12 months, respectively. The Y detrusorrhaphy technique was successful in 91.6 and 97.4% of cases at 3 and 12 months, respectively. The difference in the techniques was not statistically significant. Urinary retention developed in 8.4% of the patients who underwent Y detrusorrhaphy compared to 15.2% of those who underwent the advancing suture technique (not statistically significant). However, patients with grades IV and V reflux, children younger than 3 years and boys had significantly (p <0.05) higher postoperative retention rates of 24.6, 35.6 and 20.3%, respectively, when all 220 patients were considered. CONCLUSIONS: Each modification of the original Lich-Gregoir technique is highly effective for treating bilateral vesicoureteral reflux and each is associated with a low rate of temporary urinary retention. Although there seems to be a lower incidence of retention with the Y detrusorrhaphy technique, this was not statistically significant. Because of the higher incidence of urinary retention in young children, boys and/or patients with high grade reflux, we recommend that physicians consider a longer period of catheterization regardless of the technique chosen.

Child↗

PubMed1999

Concomitant modified bladder neck closure and Mitrofanoff urinary diversion.

PURPOSE: We describe a modification of bladder neck closure for managing urinary incontinence in children. MATERIALS AND METHODS: In 11 patients with intractable urinary incontinence that persisted after multiple failed surgical procedures we performed modified bladder neck closure with construction of a catheterizable continent conduit. RESULTS: Mean followup is 3 years. All patients were continent after the procedure and none had a fistula or urinary leakage. One patient required stomal and conduit revision, and bladder stones in 3 necessitated endoscopic removal. CONCLUSIONS: We recommend this modified technique of bladder neck closure as an option for managing urinary incontinence in a complex group of children because it allows the achievement of continence with minimal morbidity.

Adolescent↗