Biomedical subjects

D A Canning

Publications and source records attributed to D A Canning.

67 records · Page 4Linked to original sources

PubMed1993

Techniques to create continence in the failed bladder exstrophy closure patient.

We reviewed retrospectively 315 patients with bladder exstrophy treated at our hospital between July 1976 and April 1992 to assess the outcome of those who failed primary closure of the bladder. Of the patients 47 required reclosure of the bladder, including 28 who have undergone a procedure to restore urinary continence. Methods used to achieve dryness included bladder neck reconstruction in 18 patients, bladder neck reconstruction along with augmentation in 4, augmentation alone in 4, repeat bladder neck reconstruction in 1, and reclosure with creation of a continent stoma and augmentation in 1. Nine of 18 patients who underwent primary bladder neck reconstruction are dry on intermittent catheterization, while 8 of the remaining 9 are dry and voiding without catheterization. Four patients who underwent primary bladder neck reconstruction and augmentation, and 4 who underwent augmentation after bladder neck reconstruction are dry on intermittent catheterization. The patient who underwent reclosure, bladder augmentation and creation of a continent abdominal stoma is dry on intermittent catheterization. Virtually all patients who failed the initial closure and later bladder neck reconstruction for continence require augmentation and intermittent catheterization to remain dry. Of 28 patients who underwent salvage procedures only 1 had upper tract changes. With attention to detail and the use of a variety of reconstructive techniques children who have failed exstrophy closure can achieve continence and have stable renal function.

Bladder Exstrophy↗

PubMed1993

Histological and histochemical study of the vesicoureteric junction in infancy and childhood.

The morphology of the vesicoureteric junction was compared using 19 post mortem specimens obtained from male and female Afro-American and Caucasian children with an age range of 1 to 72 months (mean 4). All specimens were serially sectioned and the tissues processed using standard histological and histochemical techniques (acetylcholinesterase ¿AChE¿ and pseudocholinesterase ¿PChE¿). The results failed to reveal any differences in the structure of the vesicoureteric junction with respect to age, sex and ethnic origins. The vesicoureteric junction comprised 3 histologically and histochemically distinct smooth muscle components. Ureteric muscle formed a complete inner layer rich in PChE which continued beyond the ureteric orifices to merge distally with the superficial trigone. An intermediate layer of muscle was also demonstrated whose constituent muscle cells possessed specific histological features and which was rich in both AChE and PChE, which is distinct from that derived from the ureter and detrusor. The presence of detrusor muscle on the outer aspect of the juxtavesical segment of ureter rich in AChE was also confirmed. While this study, using histochemical studies in infants and children, did not reveal any differences in the structure of the vesicoureteric junction with respect to age, sex or ethnic origin, an intermediate layer of muscle was identified with histochemical characteristics more like that of the male genital tract than that derived from the ureter or detrusor muscle.

Acetylcholinesterase↗

PubMed1992

An immunohistochemical study of human postnatal paraganglia associated with the urinary bladder.

Histological and immunohistochemical methods were used to study pelvic paraganglia in a series of human postnatal specimens ranging in age from 1 month to 6 y. Up to 5 months of age, many of the encapsulated paraganglia contained small pacinian-like sensory corpuscles which occurred either singly or in small clusters, implying an unknown functional interrelationship during this period. In older specimens, this intimate association was not observed since pacinian corpuscles and small nonencapsulated clusters of paraganglion cells were observed only as separate structures. It is suggested that the paraganglion cells may induce the formation of the pacinian corpuscles during fetal development. Immunohistochemistry using the nerve marker protein gene product (PGP 9.5) demonstrated a rich plexus of varicose nerve fibres within the paraganglia which may directly innervate the paraganglion cells and/or be associated with the profuse vascular supply. A similar density of vasoactive intestinal polypeptide-containing nerves was also demonstrated while some of the nerves contained calcitonin gene related peptide or substance P. The paraganglion cells stained positively for tyrosine hydroxylase, dopamine-beta-hydroxylase and neuropeptide Y, but not for phenylethanolamine N-methyltransferase. This combination of immunostaining confirms them as a rich source of noradrenaline.

Age Factors↗

PubMed1991

Failed bladder neck reconstruction: options for management.

During the last 10 years 17 patients have been seen at this institution for persistent urinary incontinence after Young-Dees-Leadbetter bladder neck reconstruction. Of these patients 16 were born with classical bladder exstrophy and 1 with complete epispadias. Six patients underwent 1, 10 underwent 2 and 1 underwent 3 prior bladder neck procedures. As salvage procedures 8 patients underwent another Young-Dees-Leadbetter procedure, 1 repeat bladder neck reconstruction and augmentation cystoplasty, 3 augmentation alone, 4 bladder augmentation with creation of a continent abdominal stoma and 1 augmentation with implantation of an artificial urinary sphincter. Of the 8 patients who underwent a repeat Young-Dees-Leadbetter procedure 7 are dry for 3 hours or more and 1 is dry for greater than 3 hours on intermittent self-catheterization. All of those who are dry for greater than 3 hours are dry at night and 1 wears pads when engaging in strenuous physical activity. Of the 9 patients who underwent augmentation cystoplasty along with other adjunctive procedures 8 are continent for greater than 3 hours on intermittent catheterization, 6 are dry at night if they perform catheterization at bedtime and 1 remains totally incontinent after removal of the artificial urinary sphincter. Thus, with persistence and creativity a child with a previously failed bladder neck reconstruction or even multiple failed repairs can be made socially continent, providing a satisfactory alternative without resorting to urinary diversion.

Adolescent↗

PubMed1991

Nonsurgical management of primary vesicoureteral reflux in complete ureteral duplication: is it justified?

We reviewed the treatment of 56 children with vesicoureteral reflux and complete duplication of the collecting system, including 14 who had complete bilateral duplication. A total of 70 refluxing duplicated systems was analyzed. Of the patients 18% demonstrated spontaneous resolution of reflux within 42 months, 23% are currently stable on prophylactic antibiotics and 57.1% underwent surgical correction. Spontaneous resolution of reflux occurred in 58% of the children with grades I to III/V reflux. In comparing the group with reflux and duplication to a group with reflux into single systems, we conclude that the patients with duplication and lower grades of reflux can be managed nonoperatively, while infection is prevented with antibiotic prophylaxis.

Child, Preschool↗

PubMed1991

Endoscopic injection of glutaraldehyde cross-linked bovine dermal collagen for correction of vesicoureteral reflux.

From November 1986 through May 1989, a Food and Drug Administration approved investigational study was done to assess the safety and efficacy of glutaraldehyde cross-linked bovine dermal collagen in the endoscopic treatment of vesicoureteral reflux. Over-all, 57 patients (92 ureters) were treated. The majority of ureters (68.5%) had grade II to III/V vesicoureteral reflux (international classification). One treatment was given in 61.4% of the patients, while 33.3% required 2 and 5.3% required 3 treatments. Nonduplicated/primarily refluxing ureters comprised 68.5% of the total, while 13% were duplex/primarily refluxing and 18.5% were surgical failures. The procedures were performed on an outpatient basis in all but 3 patients. Patients were evaluated by voiding cystourethrogram and renal/bladder sonography before and after treatment at 1 month and 1 year. Cure at 1 month after the last treatment was achieved in 75% of the ureters. Among the ureters cured at 1 month the cure persisted in 79% at 1 year after treatment. Cure at 1 year was achieved in 65% of all ureters evaluated, regardless of the status at 1 month. Procedure-related morbidity was minimal and there were no adverse reactions to the implant substance. Thus, glutaraldehyde cross-linked bovine dermal collagen appears to be safe and effective in the endoscopic treatment of vesicoureteral reflux.

Animals↗

PubMed1990

Local tissue reaction to the subureteral injection of glutaraldehyde cross-linked bovine collagen in humans.

Although the technique of subureteral injection has been widely accepted as an alternative to reimplantation in the treatment of vesicoureteral reflux, the choice of the material to be used is controversial. We have used glutaraldehyde cross-linked bovine collagen to correct vesicoureteral reflux within the context of a Food and Drug Administration approved investigational study. We report the local tissue reaction to the implanted collagen in 7 patients who underwent reimplantation 3 to 19 months after failed endoscopic therapy. Glutaraldehyde cross-linked bovine collagen engendered a minimal localized inflammatory reaction without causing granuloma formation. Subsequent reimplantation was not hindered by the presence of the implant materials.

Child↗

PubMed1990

Suspected testicular torsion and ischemia: evaluation with color Doppler sonography.

Color Doppler sonography was performed in 32 patients with a painful scrotum in whom testicular ischemia from torsion or postherniorrhaphy was clinically suspected. Surgical correlation was available in 15 patients, and scintigraphic correlation was available in 17 patients. Seven of the 32 patients were diagnosed as having testicular ischemia from torsion. Color Doppler flow imaging demonstrated a lack of intratesticular flow in six of the seven testes with torsion and relatively normal intratesticular flow in one of the patients with acute torsion. Normal or increased intratesticular flow was demonstrated by color Doppler in all 57 of the nonischemic testes. Using the single criterion of presence or absence of identifiable intratesticular flow, the authors found that color Doppler was 86% sensitive, 100% specific, and 97% accurate in the diagnosis of torsion and ischemia in the painful scrotum. Color Doppler sonography is an accurate, noninvasive means of rapidly assessing perfusion of the testis in the painful scrotum.

Acute Disease↗

PubMed1989

Nutritional consequences of bowel segments in the lower urinary tract.

To assess for altered fat absorption in a group of 26 patients who underwent bladder replacement or augmentation between 1975 and 1988 serum samples were assayed for levels of B12 and carotene. Reconstruction was done with ileum and/or cecum in 22 patients, and 4 who had undergone sigmoid cystoplasty and were not expected to be at risk for fat malabsorption were included as controls. Followup ranged from 4 months to more than 8 years. No patient demonstrated low values of B12 or carotene regardless of postoperative duration, bowel segment location or length of segment. Use of ileal segments less than 45 cm. long even with associated incorporation of the ileocecal valve and adjacent cecum does not appear to compromise fat absorption or the enterohepatic circulation.

Carotenoids↗

PubMed1989

A new technique of using the in situ appendix as a catheterizable stoma in continent urinary reservoirs.

A new technique of using the in situ appendix to construct a continent catheterizable stoma is described in a patient who underwent continent urinary diversion, and the technical aspects of this procedure are illustrated in detail. The appendix is remodeled by invaginating its base into the cecum for 1 cm., cecoplicating the middle portion for 2 cm. and bringing the distal end to the skin as a cutaneous stoma. This new technique demonstrates that the in situ appendix can be constructed successfully to provide continence without the need for isolating it from the cecum and implanting the distal end into the urinary reservoir as described in the Mitrofanoff technique.

Adult↗

PubMed1987

Testicular torsion in a 62-year old man.

A 62-year-old man is described who had surgically confirmed testicular torsion. This is the second oldest reported patient with this condition. Although uncommon in men more than 30 years old, this diagnosis should be considered when evaluating the acute scrotum in all age groups.

Age Factors↗

PubMed1986

Predictors of recurrent clinical stage I nonseminomatous testicular cancer. A prospective clinicopathologic study.

A prospective clinicopathologic study of 60 patients with clinical Stage I nonseminomatous testicular cancer (NSTC) has been reported. Of 60 patients with clinical Stage I NSTC who underwent retroperitoneal lymphadenectomy (RPLA), 6 proved to be Stage II, a staging error of 10 per cent. In 4 patients of the remaining 54, metastases developed in the lungs. In 1 patient metastases developed both in the lung and in retroperitoneal lymph nodes. There was no death in these groups of patients. These 10 patients with staging error and/or recurrence after RPLA have been analyzed for the causes of treatment failure utilizing a set of prognostic criteria (tumor cell type, vascular or lymphatic invasion in the primary tumor, extension to the spermatic cord, and size of the primary tumors). It has been concluded that embryonal carcinoma (P less than 0.001), vascular invasion (P less than 0.001), and extension of the tumor to the spermatic cord (P less than 0.001) are significant predictors of metastases and/or recurrence after RPLA in Stage I NSTC. A plan of management is suggested based on these criteria.

Humans↗

PubMedDate not supplied

Identification and management of urinary tract infection in the preschool child.

Urinary tract infections commonly occur in preschool children and can be associated with significant morbidity if they are not identified quickly and treated appropriately. Vesicoureteral reflux is found in a larger proportion of these patients. Recognizing and treating risk factors such as dysfunctional voiding may aid in the resolution of vesicoureteral reflux and reduce the recurrence of urinary tract infections.

Age Factors↗