Geometric, landmark-guided technique reduces tissue trauma, surgery time, and subjective difficulty for canine peripheral lymphadenectomies: an educational crossover study.

OBJECTIVE: To compare the effect of a geometric, landmark-guided lymphadenectomy (LL) approach to peripheral lymph nodes (LNs) on successful LN identification, surgical time, tissue trauma, and ease of LN identification compared to standard lymphadenectomy (SL) and methylene blue-guided lymphadenectomy (MBL). SAMPLE: 18 adult, mixed-breed canine cadavers operated on by 7 veterinarians and 5 fourth-year veterinary students between July 23 and October 12, 2022. METHODS: Participants were provided standardized, publicly available materials regarding the anatomy and surgical techniques for SL of 3 peripheral lymphocentrums: superficial cervical, axillary (ALN), and superficial inguinal (SILN). Participants performed the 3 SLs unilaterally on canine cadavers. Thereafter, they were randomly assigned to 2 crossover groups: MBL and LL. All dissections were separated by at least 2 weeks for each participant. Primary outcome measures included successful LN identification, surgical time, tissue trauma scores, and subjective difficulty. RESULTS: Successful LN identification was highest with LL (86%) compared to SL (69%) and MBL (67%). Subjective difficulty scores were reduced with LL for SILN dissections. Tissue trauma scores were reduced when using LL for ALN and SILN compared to MBL and SL. Time to LN identification was reduced for ALN with LL. No significant differences were observed between MBL and SL, or for the superficial cervical dissections. CLINICAL RELEVANCE: Peripheral lymphadenectomies are time consuming and difficult for veterinarians in early stages of surgical training. Little surgical guidance is provided within current literature. Geometric, landmark-guided lymphadenectomies may improve LN identification success and reduce surgical time, tissue trauma, and procedure difficulty, which could encourage their clinical application.

Glomerulotubular pathology in dogs with subclinical ehrlichiosis.

Subclinical stage of ehrlichiosis is characterized by absence of clinical or laboratory alterations; however, it could lead to silent glomerular/tubular changes and contribute significantly to renal failure in humans and animals. The aim of this study was to evaluate glomerular and tubular alterations in dogs with subclinical ehrlichiosis. We evaluated renal biopsies of 14 bitches with subclinical ehrlichiosis and 11 control dogs. Samples were obtained from the left kidney, and the tissue obtained was divided for light microscopy, immunofluorescence, and transmission electron microscopy. Abnormalities were identified by light microscopy in 92.9% of dogs with ehrlichiosis, but not in any of the dogs of the control group. Mesangial cell proliferation and synechiae (46.1%) were the most common findings, but focal segmental glomerulosclerosis and ischemic glomeruli (38.4%), focal glomerular mesangial matrix expansion (30.7%), mild to moderate interstitial fibrosis and tubular atrophy (23%), and glomerular basement membrane spikes (23%) were also frequent in dogs with ehrlichiosis. All animals with ehrlichiosis exhibited positive immunofluorescence staining for immunoglobulins. Transmission electron microscopy from dogs with ehrlichiosis revealed slight changes such as sparse surface projections and basement membrane double contour. The subclinical phase of ehrlichiosis poses a higher risk of development of kidney damage due to the deposition of immune complexes.

Hydrogen peroxide plasma sterilization of a waterproof, high-definition video camera case for intraoperative imaging in veterinary surgery.

OBJECTIVE: To evaluate the safety and usability of a wearable, waterproof high-definition camera/case for acquisition of surgical images by sterile personnel. STUDY DESIGN: An in vitro study to test the efficacy of biodecontamination of camera cases. Usability for intraoperative image acquisition was assessed in clinical procedures. METHODS: Two waterproof GoPro Hero4 Silver camera cases were inoculated by immersion in media containing Staphylococcus pseudointermedius or Escherichia coli at ≥5.50E+07 colony forming units/mL. Cases were biodecontaminated by manual washing and hydrogen peroxide plasma sterilization. Cultures were obtained by swab and by immersion in enrichment broth before and after each contamination/decontamination cycle (n = 4). The cameras were then applied by a surgeon in clinical procedures by using either a headband or handheld mode and were assessed for usability according to 5 user characteristics. RESULTS: Cultures of all poststerilization swabs were negative. One of 8 cultures was positive in enrichment broth, consistent with a low level of contamination in 1 sample. Usability of the camera was considered poor in headband mode, with limited battery life, inability to control camera functions, and lack of zoom function affecting image quality. Handheld operation of the camera by the primary surgeon improved usability, allowing close-up still and video intraoperative image acquisition. CONCLUSION: Vaporized hydrogen peroxide sterilization of this camera case was considered effective for biodecontamination. Handheld operation improved usability for intraoperative image acquisition. CLINICAL SIGNIFICANCE: Vaporized hydrogen peroxide sterilization and thorough manual washing of a waterproof camera may provide cost effective intraoperative image acquisition for documentation purposes.

Duty hours restriction for our surgical trainees: An ethical obligation or a bad idea?

To ensure patient safety and protect the well-being of interns and residents, the Accreditation Council for Graduate Medical Education (ACGME) issued guidelines in 2003 limiting the working hours of physician trainees. Although many supported the goals of the ACGME, institutions struggled to restructure their programs and hire staff required by this unfunded mandate. Numerous studies have analyzed the effects of duty hours restrictions on patient outcomes and physician training over the past 15 years. Most agree that duty hours restrictions improved well-being of house officers, but these improvements came at the expense of continuity, and patient hand-offs led to medical errors. Effects on resident training are program specific, with duty hours restrictions having the most deleterious effects on surgical disciplines. Because veterinary specialists assume a similar role in providing 24-hour patient care, interns and residents face work-related stress as a result of extended working hours, on-call duty, and an increasingly complex caseload. The North Carolina State Veterinary Hospital is staffed by approximately 100 house officers representing almost every veterinary specialty group. We surveyed departing house officers regarding their quality of life and training experience. Sixty-six percent of interns and residents reported that they do not have time to take care of personal needs, and 57%-62% felt neutral or dissatisfied with their mental and physical well-being. Most trainees believed that decreased duty hours would improve learning, but 42% believed that decreased caseload would be detrimental to training. Veterinary educators must consider post-DVM veterinary training guidelines that maintain patient care with a good learning environment for interns and residents.

Associations of patient characteristics, disease stage, and biopsy technique with the diagnostic quality of core needle renal biopsy specimens from dogs with suspected kidney disease.

OBJECTIVE To identify factors affecting the diagnostic quality of core needle renal biopsy specimens from dogs with suspected kidney disease. DESIGN Cross-sectional study. ANIMALS 522 client-owned dogs with suspected kidney disease for which core needle renal biopsy specimens (n = 1,089) were submitted to the International Veterinary Renal Pathology Service for evaluation and inclusion in their database. PROCEDURES Data regarding dog signalment, clinical variables, biopsy method, needle brand and gauge, biopsy results, and other variables were extracted from the database. Variables were tested for association with 3 outcomes of light microscopic evaluation of core specimens: number of glomeruli per core specimen, obtainment of < 10 glomeruli, and presence or absence of renal medullary tissue. RESULTS Number of glomeruli per core specimen was significantly associated with needle gauge, dog age, serum creatinine concentration, and degree of proteinuria, whereas biopsy method and submitting hospital were significantly associated with the presence of renal medullary tissue in specimens. Mean numbers of glomeruli per core specimen obtained with 14- or 16-gauge needles were similar, but both were significantly greater than the mean number obtained with 18-gauge needles. Needle gauge had a similar association with the likelihood of obtaining < 10 glomeruli in a core specimen. Specimens obtained via laparotomy or laparoscopic approaches more commonly contained medullary tissue than those obtained by ultrasound-guided approaches. CONCLUSIONS AND CLINICAL RELEVANCE Overall, findings suggested that ultrasound-guided biopsy with a 16-gauge needle should maximize the diagnostic quality of renal biopsy specimens from dogs with suspected kidney disease, while avoiding potential adverse effects caused by larger needles.

Radical Cystectomy and Cutaneous Ureterostomy in 4 Dogs with Trigonal Transitional Cell Carcinoma: Description of Technique and Case Series.

OBJECTIVE: To describe radical cystectomy followed by cutaneous ureterostomy as a treatment of invasive bladder neoplasia in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs with transitional cell carcinoma of the bladder trigone (n=4). METHODS: Perioperative complications and long-term outcomes of dogs that underwent cutaneous ureterostomy following radical cystectomy and lymphadenectomy for transitional cell carcinoma of the urinary bladder trigone were reviewed. Both ureters were transected and anastomosed to the ventral abdominal skin. Polyvinyl chloride catheters were placed in the ureteral stomas and maintained for 5 days. After catheter removal, dogs were managed with an absorbent diaper over the stomas. Long-term outcome and survival were documented by follow-up visits or phone contact. RESULTS: Median age at the time of surgery was 10.3 years (range, 8-12). Average procedural time was ∼4.7 hours (range, 3.8-6.1). Minor complications occurred in all dogs, including bleeding and edema of the ureterostomy site during the first 2-3 days after surgery. One dog developed urine scald that resolved with improved stoma care and hygiene. Median survival time after surgery was 278.6 days (range, 47-498). Distant metastases were documented in 2 dogs at 47 days (bone) and 369 days (lung) after surgery. CONCLUSION: Radical cystectomy with cutaneous ureterostomy is a viable salvage procedure for urinary diversion after cystectomy in dogs with invasive bladder neoplasia. Postoperative management and quality of life were considered acceptable by most owners. Future studies are warranted to evaluate survival time in a larger number of animals.

Prevalence of Glomerulopathies in Canine Mammary Carcinoma.

The incidence and prevalence of paraneoplastic glomerulopathy, especially associated with carcinoma, are a matter of debate and the causal link between cancer and glomerular diseases remains unclear. The aim of this study was to evaluate renal biopsies of selected bitches with spontaneous mammary gland carcinoma. We hypothesized that dogs with mammary carcinomas would show histologic evidence of glomerular pathology. A prospective study was performed in dogs with naturally occurring mammary carcinoma that were undergoing tumor resection and ovariohysterectomy. We evaluated renal biopsies of 32 bitches with spontaneous mammary gland carcinoma and 11 control dogs without mammary gland neoplasia. Samples were obtained from the left kidney and the biopsy material was divided for light microscopy (LM), immunofluorescence (IF) and transmission electron microscopy (TEM). Light microscopy abnormalities were identified in 78.1% of dogs with mammary carcinoma (n = 25) and in none of the dogs in the control group. Focal glomerular mesangial matrix expansion was the most common alteration (n = 15, 60.0%), but mesangial cell proliferation (n = 9, 36.0%) and focal segmental glomerulosclerosis (n = 9, 36.0%), synechiae (n = 7, 28.0%), and globally sclerotic glomeruli (n = 6, 24.0%) were also frequent in dogs with malignancy. Immunofluorescence microscopy revealed strong IgM staining was demonstrated in 64.3% (n = 18) of carcinoma dogs. Transmission electron microscopy from dogs with carcinoma revealed slight changes, the most frequent of which was faint sub-endothelial and mesangial deposits of electron-dense material (78%). Mesangial cell interpositioning and segmental effacement of podocyte foot processes were identified in some specimens (45%). Changes in the glomerulus and proteinuria are common in dogs with naturally occurring mammary carcinoma and this condition appears to provide an excellent large animal model for cancer-associated glomerulopathy in humans.

Laparoscopic placement and urodynamic effects of an artificial urethral sphincter in cadaveric dogs.

OBJECTIVE: To describe a laparoscopic approach for placement of a percutaneously controlled artificial urethral sphincter (AUS) in female cadaver dogs and compare the change in urethral pressure and lumen diameter after filling the device. STUDY DESIGN: Experimental study. ANIMALS: Canine female cadavers (n = 10). METHODS: A laparoscopic technique was used to implant the AUS in 10 cadaver dogs. Maximum urethral closure pressure (MUCP), cystourethral leak point pressure (CLPP), and urethral luminal area were measured at 0, 25, 50, and 75% cuff inflation. Necropsy was performed after urethral pressure profilometry and cystoscopy data collection to assess for trauma caused by the procedure. RESULTS: Laparoscopic implantation was performed successfully in all 10 cadavers with no evidence of inadvertent trauma. Median MUCP at 0% AUS fill (48.9 cmH2 O) was significantly lower than 75% fill (243.5 cmH2 O). Median CLPP at 0% fill (5.0 cmH2 O) was significantly lower than 75% fill (23.2 cmH2 O). Significant differences were also found comparing urodynamic values 25 to 50%, 25 to 75%, and 50 to 75%. Cystoscopic evaluation revealed progressive decreases in urethral lumen area and significant differences between the urethral luminal area values as the AUS cuff was inflated. CONCLUSION: Laparoscopic placement of an AUS can be performed successfully in cadaver dogs, improved urethral pressure profile parameters, and visibly occluded the urethral lumen. Further studies of laparoscopic placement in clinical cases affected by urethral sphincter mechanism incompetence are warranted.

Suture-Free Ureterovesical Anastomosis Using a Microvascular Anastomosis System: Canine Cadaveric Study.

OBJECTIVE: To describe a suture-free ureterovesical anastomosis using a microvascular anastomotic system (MAS) and compare the surgical time and bursting pressure to a sutured ureterovesical anastomosis (SA) with and without an extravesical seromuscular tunnel (EVSMT). STUDY DESIGN: Randomized, unblocked design, ex vivo study. ANIMALS: Three canine cadavers. METHODS: For each cadaver, the ureters were sectioned into 3 equal lengths. The 6 sections were randomly assigned to receive either the MAS or end-side SA. The first cadaver (3 MAS, 3 SA) was used to refine the technique, and the remaining 2 cadavers were used for evaluation. Surgical time and bursting pressure of the anastomosis were compared between MAS and SA (n = 6 per technique). After bursting pressure testing of each anastomosis, an SMT was created over the anastomoses. Bursting pressures were again recorded and compared across techniques. RESULTS: The surgery time was significantly shorter for MAS (median 5.4 minutes) than SA (median 15.8 minutes; P = .002). The bursting pressure was significantly higher for MAS (median 189.5 cmH2 O) than SA (median 64 cmH2 O; P = .002). The bursting pressure for MAS-EVSMT (median 398.5 cmH2 O) was not significantly different from the SA-EVSMT (median 321 cmH2 O, P = .567); however, the creation of an SMT significantly increased the bursting pressure for both techniques (P = .028, respectively). CONCLUSION: This study demonstrated the feasibility of a suture-free ureterovesical anastomosis in the canine cadaver using a commercially available MAS. The MAS anastomosis was faster and resulted in higher bursting pressures than SA. The creation of an SMT improved the bursting resistance of both techniques but there was no difference between the techniques covered by an EVSMT.

Suture-free technique for canine ureteral resection-anastomosis using a microvascular anastomotic system: a cadaveric study.

OBJECTIVE: To describe a suture-free technique for canine ureteral resection-anastomosis using a microvascular anastomotic system (MAS) and to compare surgical time and burst pressure of hand-sewn (HS) ureteral end-to-end anastomosis with the MAS technique. STUDY DESIGN: Experimental ex vivo study. ANIMALS: Canine cadavers (n = 8). METHODS: For each cadaver, 1 ureter was randomly assigned to undergo HS anastomosis and the contralateral ureter had MAS anastomosis. The first 3 cadavers (6 ureters) were used to refine the MAS technique. In the other 5 dogs, surgical time and ureteral burst pressure were compared between groups (n = 5 ureters/group). RESULTS: Preliminary procedures showed that selective impaling of the mucosa and submucosa (without muscularis and adventitia) is necessary to allow complete mechanical interlock of the anastomotic rings for the MAS technique. Median anastomotic time was significantly shorter for MAS (7.6 min) than HS (16.6 min; p = .029) and burst pressure higher for MAS (393 cm H2 O) than HS (180 cm H2 O; p = .012). CONCLUSION: This study demonstrated the feasibility of a suture-free technique of canine ureteral resection-anastomosis using a commercially available MAS. The MAS anastomosis was faster and had higher burst strength compared with the HS anastomosis.

Complications of upper urinary tract surgery in companion animals.

Due to the negative effects of urine on wound healing, the high rate of complications associated with surgical incisions in the ureter and a desire to avoid large open approaches to the abdomen, there is a strong trend in human medicine toward the use of endoscopic methods in the treatment of upper urinary tract disease. However, the small size of urogenital structures in companion animals has prevented the widespread application of endoscopy of the upper urinary tract and surgery continues to be the mainstay of treatment. Through careful decision making, veterinary surgeons now use microsurgical technique and interventional radiology to provide a high success rate. The current review will discuss complications pertaining to surgery of the kidney and ureter in companion animals, using experimental and clinical data to guide the detection and avoidance of these complications.

Complications of ovariohysterectomy and orchiectomy in companion animals.

Complications following elective spay or neuter procedures are particularly feared by new graduates. However, even the most experienced surgeons may encounter surgical or postoperative complications. At best, complications associated with elective procedures can harm the doctor-client relationship. At worst, these can present legal and financial problems. Veterinary surgeons should be aware of the potential complications associated with elective sterilization, these should be communicated to the client, and there should be a clear plan for action when a complication occurs. This article reviews the reported complications encountered in elective sterilization surgery in companion animals, with a special focus on early detection and prevention.

Bladder inversion and secondary hematuria in a 6-month-old domestic shorthair cat.

CASE DESCRIPTION: A 6-month-old female domestic shorthair cat was admitted for evaluation of intermittent clinical signs of hematuria and inappropriate urination for the past 2 months. CLINICAL FINDINGS: Transabdominal ultrasonography revealed a multilayered mass in the urinary bladder apex consistent with full-thickness invagination of the bladder wall. TREATMENT AND OUTCOME: Exploratory surgery was performed, and partial inversion of the urinary bladder was confirmed. The invaginated bladder apex was manually reduced, and partial cystectomy was performed to remove the invaginated section of bladder wall. Histologic findings were consistent with vascular congestion and edema secondary to partial invagination. Bacterial culture of a section of the bladder mucosa demonstrated concurrent bacterial urinary tract infection. Clinical signs resolved following surgical resection of the bladder apex and antimicrobial treatment for the concurrent urinary tract infection. CLINICAL RELEVANCE: Partial invagination of the urinary bladder should be considered in the differential diagnosis for cats with clinical signs of hematuria, stranguria, and inappropriate urination. A diagnosis may be made on the basis of detection of invaginated tissue in the bladder apex during abdominal ultrasonography.

Long-term efficacy of a percutaneously adjustable hydraulic urethral sphincter for treatment of urinary incontinence in four dogs.

OBJECTIVE: To evaluate the efficacy of a surgically placed, static hydraulic urethral sphincter (SHUS) for treatment of urethral sphincter mechanism incompetency (USMI). STUDY DESIGN: Prospective study. ANIMALS: Spayed female dogs (n=4) with acquired USMI. METHODS: Urinary incontinence was assessed using a subjective continence score before and after implantation of an SHUS on the proximal urethra via ventral median celiotomy. Dogs were assessed for urinary continence, urinary tract infections, and implant-associated complications for 30 months. Residual incontinence was treated with percutaneous inflation of the SHUS with sterile saline solution through a biocompatible subcutaneous administration port. RESULTS: At last follow-up (26-30 months after surgery), continence scores improved from a median preoperative score of 3/10 to a median postoperative score of 10. One dog developed wound drainage over the subcutaneously placed administration port but remained continent after port removal. Three occluders were percutaneously filled with additional saline (median, 0.18 mL; mean, 0.16 mL) to improve continence after surgery. CONCLUSIONS: Application and adjustment of an SHUS provided sustained improvements in continence score in all dogs. CLINICAL RELEVANCE: In this pilot study, 3 of 4 dogs with hydraulic urethral sphincter implantation had successful percutaneous adjustment and maintained improved continence scores for 2 years after surgery. Continence was maintained in the 4th dog even after administration port removal. Based on this pilot study, the SHUS warrants further clinical evaluation for treatment of dogs with USMI unresponsive to medical management.

Effects of ischemia-reperfusion injury on renal ammonia metabolism and the collecting duct.

Acute renal injury induces metabolic acidosis, but its specific effects on the collecting duct, the primary site for urinary ammonia secretion, the primary component of net acid excretion, are incompletely understood. We induced ischemia-reperfusion (I/R) acute renal injury in Sprague-Dawley rats by clamping the renal pedicles bilaterally for 30 min followed by reperfusion for 6 h. Control rats underwent sham surgery without renal pedicle clamping. I/R injury decreased urinary ammonia excretion significantly but did not persistently alter urine volume, Na(+), K(+), or bicarbonate excretion. Histological examination demonstrated cellular damage in the outer and inner medullary collecting duct, as well as in the proximal tubule and the thick ascending limb of the loop of Henle. A subset of collecting duct cells were damaged and/or detached from the basement membrane; these cells were present predominantly in the outer medulla and were less frequent in the inner medulla. Immunohistochemistry identified that the damaged/detached cells were A-type intercalated cells, not principal cells. Both TdT-mediated dUTP nick-end labeling (TUNEL) staining and transmission electron microscopic examination demonstrated apoptosis but not necrosis. However, immunoreactivity for caspase-3 was observed in the proximal tubule, but not in collecting duct intercalated cells, suggesting that mechanism(s) of collecting duct intercalated cell apoptosis differ from those operative in the proximal tubule. We conclude that I/R injury decreases renal ammonia excretion and is associated with intercalated cell-specific detachment and apoptosis in the outer and inner medullary collecting duct. These effects likely contribute to the metabolic acidosis frequently observed in acute renal injury.

Epidemiologic factors associated with the anatomic location of intrahepatic portosystemic shunts in dogs.

OBJECTIVE: To determine whether breed, sex, country of origin, and age are associated with anatomic location of intrahepatic portosystemic shunts (IHPSS) in dogs. STUDY DESIGN: Multi-institutional retrospective case series. SAMPLE POPULATION: Dogs (n=125) with IHPSS from the veterinary teaching hospitals of the University of Florida (21), Sydney University (44), and the University of California-Davis (60). METHODS: Dogs with surgical/necropsy confirmation of single IHPSS were identified. Data were analyzed using logistic regression for associations between age, breed, sex, and country with the anatomic location of IHPSS. RESULTS: Right (34%), left (34%), and central divisional IHPSS (32%) were prevalent with approximately equal frequency in Australia; in the United States, the prevalence of right (24%) and central divisional (26%) combined was similar to left divisional IHPSS (51%). Country (P=048), sex (P=.016), and Australian cattle dog ([ACD], P=.025) were significantly associated with IHPSS location. Dogs in Australia had 2.5-fold higher odds of having right versus left divisional IHPSS. Males and ACD had 2.8- and 5.6-fold higher odds of having right versus left divisional IHPSS. Australian dogs were significantly older than those in the United States (P<.0001) and ACD were significantly older than other breeds (P=.0067). CONCLUSIONS: Although country of origin, breed, and sex had significant associations with anatomic location of IHPSS, signalment does not appear to be a strong predictor of shunt location when used alone. CLINICAL RELEVANCE: For the common breeds in this report, signalment is only occasionally helpful in predicting likelihood of anatomic division in IHPSS. Australian cattle dogs and male dogs have a statistical association with right (versus left) divisional IHPSS. If advanced imaging techniques are not available, veterinary surgeons should be prepared to locate and address any anatomic configuration of IHPSS in a dog.

Outcome associated with use of a percutaneously controlled hydraulic occluder for treatment of dogs with intrahepatic portosystemic shunts.

OBJECTIVE: To evaluate efficacy of a hydraulic occluder (HO) used for treatment of dogs with an intrahepatic portosystemic shunt (IHPSS). DESIGN: Prospective study. ANIMALS: 10 dogs with an IHPSS. PROCEDURES: Serum biochemical and postprandial bile acids (PPBA) analyses and transcolonic scintigraphy were performed before surgery. Laparotomy was performed, and an uninflated HO was placed around the portal vein branch leading to the IHPSS. After surgery, 0.9% NaCl solution was injected into subcutaneous injection ports at 2, 4, 6, and 8 weeks to achieve staged occlusion of the HO. Serum biochemical analyses, PPBA analysis, and scintigraphy were performed 2 weeks after occlusion. Serum biochemical analyses were repeated 1 year after surgery. RESULTS: Implant revision was required in 3 dogs because of rupture of the HO (n = 2) or detachment of the actuating tubing (1). Serum biochemical values and clinical signs improved in all dogs after surgery. Six of 10 dogs had PPBA concentration within reference range 2 weeks after occlusion, and 2 additional dogs had concentrations within reference range at 1 year. Only 5 of 10 dogs had complete resolution of portosystemic shunting 2 weeks after occlusion. Two dogs were lost to follow-up, and 8 dogs remained alive with no recurrence of clinical signs at a median of 22 months after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Use of the HO appeared to be an effective method for surgical treatment for dogs with IHPSS, although problems with implant reliability indicate a need for modifications in design and manufacturing.

Biomechanical and histologic comparison of single-layer continuous Cushing and simple continuous appositional cystotomy closure by use of poliglecaprone 25 in rats with experimentally induced inflammation of the urinary bladder.

OBJECTIVE: To biomechanically and histologically compare single-layer continuous Cushing and simple continuous appositional cystotomy closure in rats with xylene-induced cystitis. ANIMALS: 40 female Sprague-Dawley rats. PROCEDURE: Rats were anesthetized, their urinary bladders catheterized and evacuated, and xylene instilled in each bladder for 5 minutes and then aspirated. Forty-eight hours later, ventral midline celiotomy and cystotomy (8 mm) were performed. Cystotomies were closed with 6-0 poliglecaprone 25 by use of a single-layer continuous Cushing or simple continuous appositional pattern (20 rats/group), and cystotomy times were recorded. Rats were allocated to healing durations (5 rats/group) of 0, 3, 7, and 14 days. Celiotomies were closed in a routine manner. After the allotted healing interval, another celiotomy was performed, the urethra cannulated, and ureters ligated. The cannula was secured to the urethra, and the bladder infused at 0.1 mL/min. Leak pressure volume, leak pressure, peak pressure volume, and peak pressure were recorded via a pressure transducer. Bladders were harvested and histologically assessed. RESULTS: Cystotomy time, biomechanical testing values, and overall inflammation scores did not differ between closure methods for any healing duration. Both methods had significantly greater leak pressures, with the appositional method also having significantly greater peak pressures on day 7, compared to day 0. Biomechanical testing values decreased from day 7 to 14 as a result of juxtaincisional weakening of the bladder and xylene-induced changes in collagen. CONCLUSIONS AND CLINICAL RELEVANCE: Simple continuous appositional was equal biomechanically and histologically to continuous Cushing for all comparison variables. Poliglecaprone 25 was acceptable for cystotomy closure.