Urinary bladder wall substitution using autologous tunica vaginalis in male dogs

Evaluation of the safety and feasibility of electrochemotherapy with intravenous bleomycin as local treatment of bladder cancer in dogs

Local treatment of canine urothelial carcinoma (UC) of the bladder is a challenge. More than 90% of the cases invade the muscular layer, more than 50% develop on bladder sites with a difficult surgical approach and often requiring radical surgical procedures. This study aims to evaluate the safety and feasibility of electrochemotherapy (ECT) with intravenous bleomycin (BLM) as a local therapy for bladder UC. This prospective study included 21 dogs with spontaneous bladder UC. Regional/distant metastases and neoplastic infiltration of the serosa was considered the main exclusion criteria. We had no deaths during ECT or in the immediate postoperative period, and no suture dehiscence. Most dogs (19/21) developed mild adverse effects, whereas two dogs developed ureteral stenosis. Complete response (CR) was achieved in 62% of the cases (13/21), while partial response (PR) was achieved in 24% (5/21). The median survival and disease-free survival times were 284 and 270 days, respectively. Overall survival was significantly better in the dogs who achieved a CR. In conclusion, ECT was well-tolerated in dogs with UC, demonstrating its safety and feasibility. These data pave the way for new studies aimed at evaluating the effectiveness of ECT in canine bladder UC as a translational model for human disease.

A Systematic Review of Canine Cystectomy: Indications, Techniques, and Outcomes

This review provides a summary of the literature encompassing partial and total cystectomy procedures in dogs and subsequent conclusions that can be drawn. Surgical excision as a component of treatment for lower urinary tract neoplasia in dogs may enhance survival time and result in acceptable quality of life, though risk for surgical complications is substantial, particularly following total cystectomy procedures. However, for dogs with urothelial carcinoma, cystectomy is generally not considered curative and disease progression is common. Appropriate case selection and thorough preoperative discussion with owners regarding potential risks and benefits of cystectomy are imperative for successful outcomes.

Augmentation cystoplasty in dogs: A comparative study of different tunica vaginalis grafts

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Tunica vaginalis allograft and sheep tunica vaginalis decellularized extracellular matrix successfully rebuilt the bladder wall with minor complications in dogs.

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Sheep tunica vaginalis xenograft has disappointing results in the canine model since the bladders became contracted with decreased capacity.

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Tunica vaginalis grafts represent a simple and low-cost choice for augmentation cystoplasty in dogs.

In veterinary practice, numerous urological disorders that cause bladder dysfunction necessitate augmentation cystoplasty (AC). The purpose of this study is to evaluate the dog tunica vaginalis allograft (DTVA), sheep tunica vaginalis xenograft (STVX) and sheep tunica vaginalis decellularized extracellular matrix (STVDEM) as graft materials for urinary bladder (UB) reconstruction following a 45±5% cystectomy model in dogs. In this study, 18 adult apparently healthy mongrel dogs of both sexes were divided into three groups (6 dogs each): the DTVA group, the STVX group, and the STVDEM group. The evaluation of the AC in different groups was carried out using clinical, hematological, serum biochemical, urine, ultrasonographic, retrograde positive cystogram, and histopathological analysis all over the study period of 12 weeks. The dogs in all groups survived the procedures, except three dogs died from both STVX and DTVA groups. The mean bladder capacity indicated that the DTVA and STVX groups had regained 82.22% and 68.62%, respectively, of their preoperative baseline capacity. Interestingly, the STVDEM group's bladder capacity increased to 113.70%. Although histological analysis revealed that the three grafts successfully rebuilt the bladder wall, the STVDEM demonstrated well-organized and well-differentiated epithelial and muscular tissues that resembled, but were not identical to, native UB tissues. As a result, STVDEM is proposed as an ideal and potential acellular graft for UB reconstruction in dogs, whereas DTVA and STVX could be employed in emergencies requiring UB reconstruction.

Case Report: Surgical Treatment for Intranasal Meningoencephalocele in a Cat

A 4-month-old cat with epileptic seizures and nasal discharge was presented, and diagnosed with intranasal meningoencephalocele based on the clinical symptoms and findings of CT and MRI. As liquorrhea was suspected, the meningoencephalocele was surgically excised and the postoperative course was favorable. For cribriform plate reconstruction, the autologous tunica vaginalis was used. Rhinorrhea of the cerebrospinal fluid and seizures disappeared after surgery. On CT and MRI at 7 months after surgery, septum formation between the cranial and nasal cavities was confirmed. Currently, no seizures have occurred even though no oral antiepileptic agent was administered. There are few reports of surgical treatment for meningoencephalitis, and there are no reports of reconstruction of the cribriform plate using tunica vaginalis, so we reported the details.

A combined protocol with piroxicam, chemotherapy, and whole pelvic irradiation with simultaneous boost volumetric modulated arc radiotherapy for muscle-invasive canine urinary transitional cell carcinoma: First clinical experience

The aims of this pilot study were to evaluate the feasibility and efficacy of high-dose hypofractionated volumetric modulated arc radiotherapy (VMAT) applied to whole pelvic region radiotherapy (WPRT) with multilevel simultaneous integrated boost (MLSIB) combined with piroxicam and chemotherapy for the treatment of canine transitional cell carcinoma (TCC) of the lower urinary tract with muscle invasion TCC. Twelve dogs were enrolled, according to stage, in two groups: group 1, TCC confined to the urinary tract; group 2, TCC with metastasis. The planning target volume dose was tailored from 36 to 42 Gy in 6 fractions. All dogs were prescribed piroxicam and radiosensitizing carboplatin, and six received chemotherapy after radiotherapy. Serial follow-ups with computed tomography and magnetic resonance imaging were performed. Disease control and toxicity effects were evaluated according to the Response Evaluation Criteria in Solid Tumors and Veterinary Radiation Therapy Oncology Group criteria. The treatment was well tolerated, and no high-grade side effects were reported. The median overall survival times for groups 1 and 2 were 1,230 and 150 days, respectively. A considerable percentage of patients in group1 (50%) were still alive at the time of writing this paper, and a longer follow-up could enable a more accurate survival analysis. This preliminary analysis shows that VMAT applied to the WPRT with MLSIB is an effective and safe option for dogs with lower urinary TCC, although the presence of metastases worsens the prognosis.

Autologous tunica vaginalis graft to repair perineal hernia in shelter dogs

In an effort to reduce shelter intake, Miami-Dade Animal Services (MDAS) Pet Retention Program offers caretakers with an opportunity to have animals treated for certain medical conditions, free of charge. Discovery of new, simple surgical techniques for low-cost procedures provides veterinarians with more surgical solutions, expands the capacity for services provided through low-cost veterinary clinics and other shelter programs, and provides shelters with life-saving alternatives that will increase adoptability of homeless pets and reduce euthanasia rates. The aim of this clinical trial was to describe and to evaluate the use of the autologous tunica vaginalis communis as a free graft to repair perineal hernia (PH) in intact male dogs at an animal shelter facility. In 2018, seven male intact dogs, diagnosed with perineal hernias (PH), were presented to MDAS. All dogs had the surgical reconstruction of the pelvic diaphragm repaired by using the tunica vaginalis communis obtained at the time of castration, prior to the perineal access, and sutured directly into the perineal defect. Clinical outcome including postoperative complications and hernia recurrence were obtained via telephone communication. The median follow-up time was 13 months. None of the dogs included in this study had recurrence of the PH. All dogs were adopted, were transferred to animal rescue organizations or were returned to their owners after the surgical procedure. The use of tunica vaginalis communis autograft is a simple, low-cost surgical technique that requires less surgical expertise and training and can be used for perineal herniorrhaphy in dogs, without long-term recurrence.

Túnica vaginal autógena para herniorrafia perineal em cães

RESUMO A túnica vaginal possui características ideais para enxertia e já foi empregada na reparação de diversos tecidos, inclusive do diafragma pélvico. Objetivou-se avaliar a aplicabilidade da túnica vaginal como enxerto autógeno livre, em dupla camada, para a reparação do diafragma pélvico em 14 cães portadores de hérnia perineal, das quais, nove eram unilaterais e cinco, bilaterais. Após a orquiectomia, as túnicas de ambos os testículos foram coletadas, sobrepostas e fixadas entre si por meio de quatro pontos de reparo. Foi realizada abordagem ao saco herniário, inspeção, redução do conteúdo herniário, desbridamento muscular e síntese primária mediante sutura. O enxerto foi fixado à musculatura remanescente por meio de pontos simples separados e, posteriormente, encoberto pela sutura intradérmica e por síntese cutânea. Observações transoperatórias e, posteriormente, avaliações clínicas e ultrassonográficas, por período de um ano, permitiram sugerir que a túnica vaginal possui atributos ideais para a reparação do diafragma pélvico. Conclui-se que o enxerto autógeno livre de túnica vaginal, em dupla camada, é exequível e aplicável para o reparo do diafragma pélvico no tratamento da hérnia perineal em cães.

Lower Urinary Tract Neoplasia

Lower urinary tract neoplasia in companion animals is a debilitating and often life-threatening disease. Tumors of the bladder, urethra, and prostate often occur independently, although extension of these tumors into adjacent regions of the lower urinary tract is documented frequently. The most common lower urinary tract tumor in dogs and cats is transitional cell carcinoma (TCC). In both dogs and cats, TCC affecting the urinary bladder is generally considered to be highly aggressive with both local and metastatic disease potential, and this disease poses unique treatment challenges. Whereas much literature exists regarding the TCC disease process, treatment options, and prognosis in dogs, relatively few studies on feline TCC have been published due to the lower incidence of TCC in this species. Prostate tumors, most commonly adenocarcinomas, occur less commonly in dogs and cats but serve an important role as a comparative model for prostate neoplasia in humans. This article serves as a review of the current information regarding canine and feline lower urinary tract neoplasia as well as the relevance of these diseases with respect to their human counterparts.

A Review of the Surgical Management of Perineal Hernias in Dogs

Perineal hernia refers to the failure of the muscular pelvic diaphragm to support the rectal wall, resulting in herniation of pelvic and, occasionally, abdominal viscera into the subcutaneous perineal region. The proposed causes of pelvic diaphragm weakness include tenesmus associated with chronic prostatic disease or constipation, myopathy, rectal abnormalities, and gonadal hormonal imbalances. The most common presentation of perineal hernia in dogs is a unilateral or bilateral nonpainful swelling of the perineum. Clinical signs do occur, but not always. Clinical signs may include constipation, obstipation, dyschezia, tenesmus, rectal prolapse, stranguria, or anuria. The definitive diagnosis of perineal hernia is based on clinical signs and findings of weak pelvic diaphragm musculature during a digital rectal examination. In dogs, perineal hernias are mostly treated by surgical intervention. Appositional herniorrhaphy is sometimes difficult to perform as the levator ani and coccygeus muscles are atrophied and unsuitable for use. Internal obturator muscle transposition is the most commonly used technique. Additional techniques include superficial gluteal and semitendinosus muscle transposition, in addition to the use of synthetic implants and biomaterials. Pexy techniques may be used to prevent rectal prolapse and bladder and prostate gland displacement. Postoperative care involves analgesics, antibiotics, a low-residue diet, and stool softeners.

Avaliação morfofuncional do enxerto de túnica albugínea suína na cistoplastia em ratos

RESUMO O objetivo deste trabalho é avaliar o uso da túnica albugínea suína na cistoplastia em ratos, avaliando funcionalidade, capacidade de reparação do órgão e possibilidades de complicações. Foram selecionados 30 ratos Wistar, machos, de seis meses de idade, divididos em: um grupo teste (TA), em que os animais receberam o enxerto de túnica albugínea suína após a cistectomia parcial e um grupo controle (C), em que os animais sofreram somente a cistectomia parcial. Os animais pertencentes a ambos os grupos foram divididos igualmente em subgrupos de cinco animais cada, que sofreram eutanásia em sete, 28 e 42 dias de pós-operatório. Foi realizada uma análise macroscópica e, posteriormente, uma análise histopatológica da região da ferida cirúrgica. Aos sete e 28 dias, os animais pertencentes ao grupo C e ao grupo TA apresentaram urotelização, regeneração da lâmina própria e da musculatura, porém o grupo TA apresentou menores sinais inflamatórios e maior organização tecidual, principalmente com relação à formação das fibras musculares. Aos 42 dias de pós-operatório, ambos os grupos já apresentavam características histológicas normais. Concluiu-se que o enxerto de túnica albugínea suína obteve sucesso na regeneração da bexiga de ratos, mantendo a funcionalidade do órgão, sem rejeição, e favorecendo a migração celular.

Management of transitional cell carcinoma of the urinary bladder in dogs: a review

Transitional cell carcinoma (TCC), also referred to as urothelial carcinoma, is the most common form of urinary bladder cancer in dogs, affecting tens of thousands of dogs worldwide each year. Canine TCC is usually a high grade invasive cancer. Problems associated with TCC include urinary tract obstruction, distant metastases in >50% of affected dogs, and clinical signs that are troubling both to the dogs and to their owners. Risk factors for TCC include exposure to older types of flea control products and lawn chemicals, obesity, female sex, and a very strong breed-associated risk. This knowledge is allowing pet owners to take steps to reduce the risk of TCC in their dog. The diagnosis of TCC is made by histopathology of tissue biopsies obtained by cystoscopy, surgery, or catheter. Percutaneous aspirates and biopsies should be avoided due to the risk of tumor seeding. TCC is most commonly located in the trigone region of the bladder precluding complete surgical resection. Medical treatment is the mainstay for TCC therapy in dogs. Although TCC is not usually curable in dogs, multiple drugs have activity against it. Approximately 75% of dogs respond favorably to TCC treatment and can enjoy several months to a year or more of good quality life. Many promising new therapies for TCC are emerging and with the close similarity between TCC in dogs and high grade invasive bladder cancer in humans, new treatment strategies found to be successful in canine studies are expected to help dogs and to be subsequently translated to humans.

Tissue-engineered cholecyst-derived extracellular matrix: a biomaterial for in vivo autologous bladder muscular wall regeneration

PURPOSE

To compare the biocompatibility and histological aspects of cholecyst-derived extra cellular matrix (CDECM) graft, either alone or with application of autologous detrusor muscles small fragments (ADMSF) on rabbit bladder mucosa for bladder augmentation.

METHODS

The gallbladders were acellularized and evaluated for preserved acellular matrix scaffold and biophysical properties. Thirty rabbits were divided into five groups. Rabbits in the control group underwent partial detrusorectomy followed by perivesical fat coverage. Groups I and II underwent the same procedure and bladder mucosa was covered either by acellular rabbit gallbladder (ARG) (group I) or acellular sheep gallbladder (ASG) (group II). Groups III and IV underwent detrusorectomy and the bladder mucosal was seeded by ADMSF and covered by ARG (group III), or ASG (group IV). Biopsies were taken at 4, 12, and 24 weeks postoperatively.

RESULTS

Higher expression of CD34 endothelial progenitor cells, CD31 microvessels, α-smooth muscle actin, S100, and cytokeratin with more organized muscular wall generation was demonstrated in groups III and IV. Expression of IHC markers was higher in groups III and IV compared with groups I and II in all the time points.

CONCLUSION

The current study confirmed that autologous fragment-seeded CDECM can be considered as a reliable natural collagen scaffold for bladder augmentation.

In-vivo autologous bladder muscular wall regeneration: application of tissue-engineered pericardium in a model of bladder as a bioreactor

PURPOSE

Tissue-engineered pericardium (TEP) is a collagen-rich matrix that has previously been shown to promote in vivo and in vitro tissue regeneration. We evaluated the potential of TEP as a source for the in-vivo creation of bladder muscular wall grafts. We used bladder wall as a bioreactor to create a natural environment for cellular growth and differentiation.

MATERIALS AND METHODS

Sixteen rabbits were divided into four groups. A control group underwent classical bladder autoaugmentation. Other groups underwent insertion of TEP between bladder mucosa and muscular layer: group 2 with insertion of TEP, group 3 with TEP over autologous bladder muscular wall fragments, and group 4 with autologous bladder smooth muscle cells (SMCs) seeded on TEP. After 4 and 8 weeks, grafts were biopsied for histopathological evaluations.

RESULTS

Frames from groups 3 and 4 demonstrated more organized muscular wall generation with a significantly higher number of CD34 + endothelial progenitor cells and CD31 + microvessels, and maintenance of α-smooth muscle actin expression through immunohistochemistry. Group 4 showed significant enhancement of SMC penetration to TEP. Although the fragment-seeded group required a simpler procedure, the cell-seeded group showed superior organization of the muscular layer on histopathology. We found a semi-organized muscular layer and new vessels in the margins of TEP in group 3, while there was a homogeneous pattern of SMCs and new vessels in both the margins and center of TEP in group 4.

CONCLUSIONS

This preliminary work has important functional and clinical implications, as it indicates that use of the autologous SMC seeding method may enhance the properties of TEP in terms of bladder wall regeneration.