Anatomical classification of feline congenital extrahepatic portosystemic shunts based on CT angiography: A SVSTS and VIRIES multi-institutional study in 231 cats.

The prevalence of anatomical-based subtypes of feline congenital extrahepatic portosystemic shunts (EHPSS) has not been completely elucidated. The goal of this study was to use CT angiography to create an anatomical-based nomenclature system for feline congenital EHPSS. Additionally, subjective portal perfusion scores were generated to determine if intrinsic portal vein development was associated with different shunt conformations or patient age at the time of CT. The SVSTS and VIRIES list services were used to recruit cases. Data collected included patient DOB, gender, breed, weight, CT date, and reported diagnosis. Shunts were classified based upon (1) the shunt portal vessel(s) of origin, (2) the shunt systemic vessel(s) of insertion, and (3) any substantial portal vessels contributing to the shunt. Additionally, hepatic portal perfusion was subjectively scored between 1 (poor/none) and 5 (good/normal) based on the caliber of the intrahepatic PVs. A total of 264 CT scans were submitted from 29 institutions. Due to exclusion criteria, 33 (13%) were removed, leaving 231 CT scans to be included. Twenty-five different EHPSS anatomies were identified with five classifications accounting for 78% of all shunts (LGP [53%], LGC-post [11%], LCG [7%], LGC-pre [4%], and PC [4%]). Shunt origin involved the left gastric vein in 75% of the described classifications. Significant differences were identified among the five most common shunt types with respect to age at the time of CT scan (P = .002), breed (P < .001), and subjective portal perfusion score (P < .001). This refined anatomical classification system for feline EHPSS may enable improved understanding, treatment comparisons, and outcome prediction for cats with these anomalies.

Protein C and comparative biochemical changes in dogs treated with percutaneous transvenous coil embolization of congenital intrahepatic portosystemic shunts.

OBJECTIVE: To evaluate protein C (PC) activity after intrahepatic portosystemic shunt (IHPSS) percutaneous transvenous coil embolization (PTCE) in dogs; to identify if PC is associated with clinical status after intervention, and to compare PC with standard biochemical values. STUDY DESIGN: Retrospective case series. ANIMALS: Forty-seven client-owned dogs with IHPSS undergoing PTCE. METHODS: Records were reviewed for preoperative and postoperative PC, hematocrit (HCT), mean corpuscular volume (MCV), albumin (ALB), and blood urea nitrogen (BUN). Ultimate clinical status was classified as excellent, fair, or poor, based on ongoing medical management and the presence of clinical signs. Intrahepatic portosystemic shunt was considered to be completely or incompletely occluded intraoperatively based on angiography. RESULTS: Postoperative PC activity increased in 37/47 (78.7%) dogs with a mean increase of 38.7% ± 2.1%. Ultimate postoperative clinical status was excellent in 16/43 (37.2%), fair in 19/43 (44.2%), and poor in 8/43 dogs (18.6%). No association was detected between preoperative PC (46.8% ± 1.8%) and ultimate clinical status but mean postoperative PC (75.7% ± 1.4%), HCT, MCV, ALB, and BUN were higher in dogs with excellent clinical status. Postoperative PC activity was higher when shunts were completely occluded (96.3% ± 10.9%), which was a finding associated with excellent status. CONCLUSION: Postoperative, but not preoperative, PC activity was higher in dogs with better ultimate clinical status. Similar trends were noted in standard hematological and biochemical values. Complete occlusion of shunts was associated with a higher postoperative PC and superior ultimate clinical status. CLINICAL SIGNIFICANCE: Postoperative PC may provide valuable information about the success of PTCE for IHPSS as it relates to the ultimate status and the need for additional procedures.

Bronchial Stent Placement for Palliative Treatment of Pulmonary Carcinoma with Bronchial Obstruction in a Cat.

A feral, domestic shorthair was evaluated for palliative treatment of a pulmonary mass with secondary pneumonia. Because of the patient's temperament and extent of the mass, tracheobronchoscopy, bronchial stenting, and biopsy were elected, followed by adjuvant radiation therapy. Stent placement across the malignantly obstructed bronchus permitted drainage and recruitment of the infected lung lobe. Uncomplicated radiation therapy, stent extension, and debulking due to tissue ingrowth were subsequently performed. Successful palliation was achieved for 323 days with subsequent progressive pulmonary and liver metastases.

Intrahepatic venous collaterals in dogs with congenital intrahepatic portosystemic shunts are associated with focal shunt or hepatic vein narrowing.

Dogs with congenital intrahepatic portosystemic shunts (IHPSS) occasionally have multiple smaller intrahepatic, tortuous blood vessels surrounding the primary shunt. This study was a retrospective, observational design that was also descriptive and anatomic in nature. Objectives were to characterize vascular morphology in IHPSS dogs presenting with intrahepatic venous collaterals (IVCs) relative to IHPSS dogs without IVCs, and to propose reasons for IVC development. The authors hypothesized that (a) IVCs develop secondary to flow resistance around a focal area of a shunt or draining hepatic vein narrowing and (b) the presence of IVC is associated with portal vessel development before intervention. Anonymized CT angiograms (CTA) and fluoroscopic portovenograms (FPV) of dogs with IHPSS were evaluated for the presence of IVCs, focal narrowing within the IHPSS, and intrahepatic portal vessels >5 mm long. Eleven of 47 (23%) dogs had IVCs identified. IVCs were significantly associated with focal narrowing in the shunt or draining hepatic vein on CTA (P = 0.039) and FPV (P = 0.021). IVCs were not associated with the presence of intrahepatic portal branches >5 mm long on portovenography (P = 0.42) or CTA (P = 0.49). Focal narrowing in the shunt (circumferential soft tissue narrowing >20% of the shunt diameter) was significantly associated with intrahepatic portal branches >5 mm long on both modalities (P < 0.001). IVCs are associated with focal narrowing of the shunt or draining hepatic vein in dogs with IHPSS. IVC should be distinguished from other conditions when evaluating a CTA for canine IHPSS.

Clinical outcomes of dogs with transitional cell carcinoma receiving medical therapy, with and without partial cystectomy.

The objective of this retrospective study was to evaluate the effects of surgery on outcome for dogs with naturally occurring urinary bladder transitional cell carcinoma. Forty-seven dogs met the inclusion criteria. Thirty-one dogs (Group A) were treated with partial cystectomy and adjunctive medical therapy and 16 dogs (Group B) were treated with medical therapy alone. Overall survival was greater in dogs treated with partial cystectomy and adjunctive medical therapy (498 days for Group A versus 335 days for Group B, hazard ratio 2.5; 95% confidence interval: 1.1 to 5.7; P = 0.026). Progression-free survival was not different between groups (85 days for Group A versus 83 days for Group B; P = 0.663). No prognostic factors were identified for progression-free survival. Due to the many cases in Group A that were lost to follow-up, time-to-event survival analysis was performed. No significant difference in overall survival was noted, and no prognostic factors were identified in the time-to-event analysis. Prospective, randomized studies are needed to determine the role of partial cystectomy in the treatment of transitional cell carcinoma.

Résultats cliniques des chiens atteints d'un carcinome à cellules transitionnelles recevant un traitement médical, avec et sans cystectomie partielle. L'objectif de cette étude rétrospective était d'évaluer les effets de la chirurgie sur les résultats chez des chiens atteints d'un carcinome à cellules transitionnelles de la vessie d'origine naturelle. Quarante-sept chiens répondaient aux critères d'inclusion. Trente et un chiens (Groupe A) ont été traités par cystectomie partielle et traitement médical d'appoint et 16 chiens (Groupe B) ont été traités par thérapie médicale seule. La survie globale était plus élevée chez les chiens traités par cystectomie partielle et traitement médical d'appoint (498 jours pour le Groupe A contre 335 jours pour le Groupe B, rapport de risque de 2,5; intervalle de confiance à 95 % : 1,1 à 5,7; P = 0,026). La survie sans progression n'était pas différente entre les groupes (85 jours pour le Groupe A contre 83 jours pour le Groupe B; P = 0,663). Aucun facteur pronostique n'a été identifié pour la survie sans progression. En raison des nombreux cas dans le Groupe A qui ont été perdus de vue lors du suivi, une analyse du temps de survie a été realisée. Aucune différence significative dans la survie globale n'a été notée et aucun facteur pronostique n'a été identifié dans l'analyse du temps de survive. Des études prospectives randomisées sont nécessaires pour déterminer le rôle de la cystectomie partielle dans le traitement du carcinome à cellules transitionnelles.(Traduit par Dr Serge Messier).

Canine and feline abdominal arterioportal communications can be classified based on branching patterns in computed tomographic angiography.

Arterioportal vascular anomalies are communications between the splanchnic arteries and the portal system that represent a rare cause of presinusoidal portal hypertension in small animals. There is little information concerning the imaging findings of arterioportal communications in small animals and no classification could be found for radiologists and surgeons. The aims of this retrospective descriptive multicentric study were to describe the computed tomographic characteristics of arterioportal communications in a group of cats and dogs, and to propose a classification based on computed tomography (CT) angiographic anatomy. Computed tomography databases from multiple veterinary hospitals were searched for cats and dogs with a diagnosis of arterioportal communication. A total of 36 animals (33 dogs, three cats) met the inclusion criteria. There were 32 intrahepatic arterioportal malformations and four extrahepatic fistulae. The intrahepatic arterioportal malformations were classified as right divisional (11/32) and left divisional (21/32), and the left divisional were subclassified as left medial (16/21) and left lateral (4/21). One patient showed multiple intrahepatic arterioportal communications with concomitant left medial and left lateral conformations. Two patients with intrahepatic arteriovenous malformation showed concomitant congenital intrahepatic shunts. The proposed anatomical classification based on CT angiography could allow veterinary radiologists to have a more systematic approach and help improve the radiologist-surgeon communication.

EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AND ENDOSCOPIC URETERAL STENT PLACEMENT IN AN ASIAN SMALL-CLAWED OTTER (AONYX CINEREA) WITH NEPHROLITHIASIS.

Urolithiasis is a significant disease concern in Asian small-clawed otters (Aonyx cinerea), with over 60% of captive animals affected. Bilateral ureteral stent placement, using endoscopic and fluoroscopic guidance, and extracorporeal shock wave lithotripsy (ESWL) were performed as salvage procedures in a 13-yr-old intact female Asian small-clawed otter following a 7-yr history of nephrolithiasis and progressive renal insufficiency. Following the procedure, radiographs revealed a slight shifting of urolith position, although a decrease in urolith mass was not observed. As a result of declining quality of life related to severe osteoarthritis, the otter was euthanized 5 wk after the procedure. While this treatment approach was unsuccessful in this case, the technique was clinically feasible, so ESWL and ureteral stent placement may remain a consideration for other individuals of this species presented earlier in the course of this disease.

Preliminary experience with stenting for management of non-urolith urethral obstruction in eight cats.

OBJECTIVE: To (1) describe minimally invasive transurethral antegrade and retrograde techniques for the placement of self-expanding metallic stents (SEMS) to reestablish urethral patency in cats with non-urolith urethral obstructions and (2) to report the procedural complications, incontinence rates, and long-term effectiveness in maintaining a patent urethra. STUDY DESIGN: Case series. ANIMALS: Cats (n = 8). METHODS: Signalment, history, clinical signs, physical examination, severity of stranguria and incontinence, clinicopathologic data, diagnostic procedures performed, diagnosis, interventional technique, type and dimensions of stent placed, complications and final outcome of 8 cats treated with SEMS for the management of urethral strictures or masses are presented. Each cat was followed for ≥12 months. Follow-up information was obtained from the medical record or by telephone interview of the owner and/or referring veterinarian. RESULTS: Four cats were continent after stent placement, 2 were moderately incontinent, and 2 were severely incontinent. Long-term follow-up (median, 462 days) was available. At follow-up, 5 cats were alive and 3 had been euthanatized at 88, 233, and 305 days. Long-term outcome, as assessed by the authors, was good (1) to excellent (3) in 4 cats, and fair (2) to poor (2) in 4 cats. Owner reported outcomes were excellent in 3/8, good to excellent in 1/8, good in 2/8, and poor in 2/8. CONCLUSION: Palliative stenting of urethral obstructions is a minimally invasive method to re-establish urethral patency in cats.

Preoperative parameters (signalment, digital radiography, urinalysis, urine microbiological culture) and novel algorithm improve prediction of canine urocystolith composition.

OBJECTIVE: To determine the accuracy of 4 preoperative parameters (signalment, urinalysis, urine microbiological culture, and digital radiography) in predicting urocystolith composition, compare accuracy between evaluators of varying clinical experience and a mobile application, and propose a novel algorithm to improve accuracy. ANIMALS: 175 client-owned dogs with quantitative analyses of urocystoliths between January 1, 2012, and July 31, 2020. METHODS: Prospective experimental study. Canine urocystolith cases were randomly presented to 6 blinded "stone evaluators" (rotating interns, radiologists, internists) in 3 rounds, each separated by 2 weeks: case data alone, case data with a urolith teaching lecture, and case data with a novel algorithm. Case data were also entered into the Minnesota Urolith Center mobile application. Prediction accuracy was determined by comparison to quantitative laboratory stone analysis results. RESULTS: Prediction accuracy of evaluators varied with experience when shown case data alone (accuracy, 57% to 82%) but improved with a teaching lecture (accuracy, 76% to 89%) and further improved with a novel algorithm (accuracy, 93% to 96%). Mixed stone compositions were the most incorrectly predicted type. Mobile application accuracy was 74%. CLINICAL RELEVANCE: Use of the 4 preoperative parameters resulted in variable accuracy of urocystolith composition predictions among evaluators. The proposed novel algorithm improves accuracy for all clinicians, surpassing accuracy of the mobile application, and may help guide patient management.

Use of a percutaneously controlled urethral hydraulic occluder for treatment of refractory urinary incontinence in 18 female dogs.

OBJECTIVE: To evaluate the efficacy and safety of a percutaneously controlled urethral hydraulic occluder (HO) device for the treatment of refractory urinary incontinence (RUI) in female dogs with various urogenital anomalies. STUDY DESIGN: Case series. ANIMALS: Female dogs with RUI (n = 18). METHODS: Retrospective evaluation of dogs after a silicone ring (HO) was surgically placed around the proximal urethra. The ring was connected to a subcutaneous injection port with actuating tubing. Residual incontinence was treated with percutaneous infusion of sterile saline into the device to provide extraluminal urethral compression. Dogs were assessed for continence (owner-assessed 10-point continence scale) and complications at standard time points. RESULTS: All 18 dogs had significantly improved continence scores (P < .001) after HO placement (median and mean score pre-HO = 2.8 and 3.3; post-HO = 10 and 8.9, respectively) with a median follow-up time of 32 months. "Functional" continence (score ≥ 9) was achieved in 67% of dogs after HO placement, though only 13/18 clients were compliant with inflations. Of dogs belonging to compliant owners, 12 (92%) had a functional continence score. Six dogs (33%) did not require inflation to achieve continence. Urethral obstruction occurred as a complication in 3 dogs. CONCLUSIONS: Use of an HO device was an effective long-term treatment for RUI when traditional options failed. The technique was associated with some complications, and these risks should be considered before use.

Comparison of computed tomography response criteria after chemoembolization of hepatic carcinoma in dogs.

The objective of this study was to evaluate unidimensional (mm), bidimensional (mm2), or tridimensional (mL) computed tomography (CT) tumor measurements for ability to discriminate changes in lesion size and predict survival in dogs with nonresectable hepatic carcinoma treated with drug-eluting bead transarterial-chemoembolization (DEB-TACE) and to compare CT response via Response Evaluation Criteria in Solid Tumors 1.1 (mm), World Health Organization (mm2), ellipsoid and spherical volume (mL), and percent necrosis, for their ability to differentiate treatment responders. This was a prospective, single-arm clinical trial. DEB-TACE was performed to varying levels of blood flow stasis in 16 client-owned dogs with nonresectable hepatic carcinoma. Computed tomography imaging responses were assessed and compared to median survival time. Results revealed that initial, follow-up, or changes in unidimensional, bidimensional, or tridimensional tumor measurements were not associated with survival. Larger bidimensional and tridimensional tumor measurements/body weight on initial and follow-up CT were significantly associated with a shorter median survival time [bidimensional (P = 0.04, 0.016) and tridimensional (P = 0.025, 0.015), respectively]. A higher percent necrosis on initial CT was significantly associated with a shorter median survival time (P = 0.038). Ellipsoid volumetric criteria detected treatment response most frequently; however, response classification was not associated with median survival time. Computed tomography bidimensional and tridimensional tumor measurements/body weight before and after DEB-TACE may help to predict median survival time for dogs undergoing DEB-TACE for hepatic carcinoma.

L'objectif de cette étude était d'évaluer les mesures tumorales unidimensionnelles (mm), bidimensionnelles (mm2) ou tridimensionnelles (mL) par tomodensitométrie (CT) pour déterminer la capacité de discriminer les changements de taille des lésions et de prédire la survie chez les chiens atteints d'un carcinome hépatique non-résécable traité avec un médicament par chimioembolisation transartérielle par billes à élution (DEB-TACE) et pour comparer la réponse CT via les critères d'évaluation de la réponse dans les tumeurs solides 1,1 (mm), l'Organisation mondiale de la santé (mm2), le volume ellipsoïde et sphérique (mL) et le pourcentage de nécrose, pour leur capacité à différencier les répondeurs au traitement. Il s'agissait d'un essai clinique prospectif à un seul volet. Le DEB-TACE a été réalisé à différents niveaux de stase du flux sanguin chez 16 chiens appartenant à des clients atteints d'un carcinome hépatique non-résécable. Les réponses d'imagerie par tomodensitométrie ont été évaluées et comparées au temps de survie médian. Les résultats ont révélé que les mesures initiales, de suivi ou les modifications des mesures tumorales unidimensionnelles, bidimensionnelles ou tridimensionnelles n'étaient pas associées à la survie. Des mesures tumorales bidimensionnelles et tridimensionnelles plus grandes/poids corporel sur la CT initiale et de suivi étaient significativement associées à un temps de survie médian plus court [bidimensionnel (P = 0,04, 0,016) et tridimensionnel (P = 0,025, 0,015), respectivement]. Un pourcentage plus élevé de nécrose au scanner initial CT était significativement associé à une durée de survie médiane plus courte (P = 0,038). Les critères volumétriques ellipsoïdes ont détecté la réponse au traitement le plus fréquemment; cependant, la classification des réponses n'était pas associée à la durée médiane de survie. La tomodensitométrie bidimensionnelle et tridimensionnelle des mesures tumorales/poids corporel avant et après DEB-TACE peut aider à prédire la durée médiane de survie des chiens subissant DEB-TACE pour un carcinome hépatique.(Traduit par Docteur Serge Messier).

Stenting of the caudal aorta and aortic trifurcation for the treatment of thrombosis in 7 dogs.

BACKGROUND: Aortic and aortoiliac thrombosis in dogs causes disease and death. OBJECTIVE: To describe the procedure and outcomes for stenting the caudal aorta and aortoiliac trifurcation. ANIMALS: Seven client-owned dogs that underwent aortic/aortoiliac stenting for treatment of thrombosis. METHODS: Retrospective multi-center investigation. Medical records were reviewed for dogs that underwent stenting of the aorta or aortoiliac trifurcation between 2008 and 2020. Information collected included history, signalment, clinicopathologic data, diagnostic imaging, procedure reports, and outcomes. RESULTS: Seven dogs with an occlusive thrombus located at or near the aortic trifurcation were included. Four of 7 dogs were non-ambulatory. Hind limbs were paretic in 5 dogs, paralyzed in 1 dog, and claudication alone was noted in 1 dog. Five of the 7 dogs had protein-losing nephropathy (PLN). Of 5 dogs with PLN, 1 had protein-losing enteropathy (PLE) and controlled hypothyroidism and 1 had caudal aortic chondrosarcoma. Two dogs had no identified underlying disease. Angiography was performed before catheter directed thrombolysis and stent placement. No deaths occurred during the procedure. Postoperative complications included pain (4/7), bruising and edema (3/7), bruising only (1/7), and edema only (1/7). Median survival time (MST) of the 7 dogs was 264 days (range, 1-1053 days). Five of 7 dogs were ambulatory within 2 days of stenting and survived to discharge with a MST of 425 days (range, 208-1053 days). CONCLUSIONS AND CLINICAL IMPORTANCE: Stenting of the aorta and aortoiliac trifurcation can provide an apparently safe and effective treatment with rapid return to ambulation for some dogs with aortic thrombosis.

Computed tomographic assessment of principal bronchial anatomy in dogs of various thoracic conformations: 93 cases (2012-2017).

OBJECTIVE: To better understand spatial relationships between principal bronchi and other intrathoracic structures by use of CT images of dogs of various somatotypes. ANIMALS: 93 dogs that underwent thoracic CT. PROCEDURES: Information was collected from medical records regarding signalment and physical examination and echocardiographic findings. Two investigators recorded multiple measurements on a thoracic axial CT image from each dog. RESULTS: Thoracic height-to-width ratio (H:W) was associated with left principal bronchus (LPB) and right principal bronchus (RPB) H:W, aortic-LPB separation, focal LPB narrowing, and aortic-vertebral overlap. Thoracic H:W was not associated with dog age, weight, sex, or brachycephalic breed. Twenty-five (27%) dogs had focal LPB narrowing, compared with 5 (5%) dogs with focal RPB narrowing (P < 0.001). Ten of 25 dogs had overlap or contact between vertebrae, aorta, LPB, and heart, suggesting a cumulative compressive effect on the LPB, while 15 had LPB-aorta contact and lack of contact between the aorta and thoracic vertebrae, suggesting an aortic constrictive effect on the LPB. None had LPB narrowing without contact from surrounding structures. Inter-rater agreement was high. CLINICAL RELEVANCE: In dogs that underwent CT and were not selected for clinical suspicion of bronchial disease, principal bronchial morphology was associated with thoracic conformation. Focal LPB narrowing occurred more often than RPB narrowing. Focal LPB narrowing occurred with evidence of extraluminal compression, with or without contact between aorta and vertebrae. Brachycephalic breed could not be used for predicting thoracic H:W.

Assessment of serum symmetric dimethylarginine and creatinine concentrations in cats with urethral obstruction.

OBJECTIVES: The aims of this study were to evaluate serum symmetric dimethylarginine (SDMA) and creatinine concentrations in cats with urethral obstruction pre- and post-decompression of the obstruction, and to determine if pre-decompression values were predictive of post-decompression renal function, as measured by SDMA and creatinine. METHODS: This was a prospective observational study. Twenty-five client-owned cats with urethral obstruction were hospitalized for decompression of the obstruction. Serum SDMA and creatinine were prospectively assessed at presentation, 24 h post-decompression and 5-20 days post-decompression. Urinalysis and culture were assessed at presentation and at the final follow-up. Exclusion criteria included positive urine culture, reobstruction or failure to obtain required samples. RESULTS: Mean SDMA concentration dropped by 41.8% from an initial pre-decompression concentration of 17.6 µg/dl to 10.3 µg/dl 24 h post-decompression (P <0.001). The mean creatinine value dropped by 38.4% from an initial pre-decompression concentration of 2.5 mg/dl to 1.5 mg/dl 24 h post-decompression (P <0.001). There was no association between SDMA concentration at initial presentation and SDMA concentration 5-20 days after urethral catheterization (Spearman's ρ = 0.205, P = 0.314). Creatinine concentration upon initial presentation was associated with the 5-20 day values after urethral catheterization (Spearman's ρ = 0.583, P <0.002). Twenty percent of cases were excluded due to bacterial growth on initial urine culture. SDMA and creatinine concentrations were significantly higher in these cases (median 59 µg/dl and 10.9 mg/dl, respectively) compared with those with negative cultures (median 14 µg/dl and 1.6 mg/dl [P <0.002 and P <0.001], respectively). CONCLUSIONS AND RELEVANCE: Both SDMA and creatinine decreased significantly after urethral catheterization, suggesting that renal function post-decompression cannot be predicted by the pre-decompression concentrations of these values.

Pharmacokinetic study comparing doxorubicin concentrations after chemoembolization or intravenous administration in dogs with naturally occurring nonresectable hepatic carcinoma.

BACKGROUND: Chemoembolization is a viable treatment option for patients with nonresectable hepatic carcinoma (HC) and may allow delivery of chemotherapeutic drugs with decreased systemic toxicity. HYPOTHESIS/OBJECTIVE: Compare the serum concentrations of doxorubicin after chemoembolization or IV administration in the same patient. We hypothesized that locoregional delivery may result in increased tumor chemotherapeutic drug concentrations, reflected by decreased measurable serum drug concentrations. Adverse hematological events were hypothesized to be decreased after locoregional delivery. ANIMALS: Seventeen client-owned dogs with incompletely resectable HC. METHODS: Prospective, single-arm clinical trial. Drug-eluting bead transarterial chemoembolization was performed to varying levels of blood flow stasis (NO STASIS, STASIS). Intravenous doxorubicin (IVC) subsequently was administered in selected patients. Systemic exposure was quantified by area under the serum doxorubicin concentration time curve (AUC), maximum serum doxorubicin concentration (Cmax ), and time doxorubicin was last above the limit of quantitation (Tlast ). Nadir test results after treatments were used to evaluate adverse hematological events. RESULTS: Thirteen NO STASIS treatments, 15 STASIS treatments, and 9 IVC treatments were performed. Maximum serum doxorubicin concentration, AUC, and Tlast were significantly lower when comparing NO STASIS or STASIS to IVC treatments. Of the patients with nadir results available, no adverse hematological events were observed after NO STASIS or STASIS treatments. Two patients developed adverse hematological events after IVC treatment. CONCLUSIONS/CLINICAL RELEVANCE: Drug-eluting bead transarterial chemoembolization offers a viable treatment option for patients with incompletely resectable HC with the potential for increased local tumor doxorubicin concentrations, decreased systemic chemotherapeutic exposure, and fewer adverse hematological events.

Evaluation of preoperative ultrasonographic parameters to predict renal recovery in long-term survivors after treatment of feline ureteral obstructions: 2012-2019.

OBJECTIVES: The aim of this study was to determine whether preoperative ultrasound imaging characteristic(s) in cats suffering from unilateral benign ureteral obstructions are predictive of outcome after successful renal decompression with a subcutaneous ureteral bypass (SUB) device. METHODS: This was a retrospective study of 37 cats with unilateral, benign ureteral obstruction. Preoperative imaging characteristics (including renal pelvis diameter, parenchymal thickness [transverse plane], renal length and pelvic size:overall renal size) and biochemical data were evaluated for all cats diagnosed with a unilateral ureteral obstruction treated with a SUB device. Any patient with bilateral obstructions or documented bacteriuria/infection in the data collection period was excluded. All patients were followed between 3 and 6 months postoperatively to obtain postoperative biochemical data. Long-term outcome was defined as serum creatinine concentration at 3-6 months postoperatively. RESULTS: No preoperative imaging characteristics or biochemical findings were found to be significantly associated with long-term serum creatinine concentrations. The length of the kidney was found to be associated with change in blood urea nitrogen and creatinine with decompression but not with long-term renal values. CONCLUSIONS AND RELEVANCE: In this study, long-term renal function based on preoperative ultrasound imaging findings could not be predicted in cats with unilateral ureteral obstruction, regardless of the severity of the biochemical parameters, renal pelvic dilation (large or small pelvis), kidney size or thickness of renal parenchyma assessed.

Bladder wall adhesion causing a vesicular septum in a dog following surgical cystotomy.

CASE DESCRIPTION: An 8-year-old spayed female Yorkshire Terrier-Poodle dog was evaluated for persistent pollakiuria and stranguria following routine cystotomy for calcium oxalate cystoliths. CLINICAL FINDINGS: The dog presented for a cystotomy with intermittent hematuria. Postoperative radiographs revealed no remaining cystoliths. Urine, cystolith, and bladder mucosal aerobic cultures were negative. Pollakiuria, stranguria, and hematuria developed immediately after surgery and persisted despite antibiotics. Ultrasound revealed suspected fibrous adhesions within the urinary bladder lumen connecting the dorsal and ventral bladder wall creating a septum. This was confirmed cystoscopically 4 weeks after surgery. TREATMENT AND OUTCOME: Cystoscopic-guided laser ablation was performed to incise abnormal tissue connecting the ventral and dorsal bladder wall using a holmium:yttrium-aluminum-garnet laser. Three weeks later, ultrasound revealed adhesion resolution though mild pollakiuria and stranguria persisted. Oxybutynin was prescribed and clinical signs resolved. At 27 months after ablation, hematuria occurred with recurrent cystoliths. These cystoliths were removed by percutaneous cystolithotomy, documenting a cystoscopically normal bladder wall. The patient had normal urination for 55.5 months after ablation, with normal bladder wall thickness on ultrasound repeated at 27 and 36 months after ablation. CLINICAL RELEVANCE: To the authors' knowledge, an adhesion creating a septum between the dorsal and ventral bladder wall has not been previously reported as a complication after cystotomy in any species and should be considered as a cause of persistent lower urinary signs after surgery. Ultrasound identified the lesion in this dog. Because bladder abnormalities can develop quickly after surgery, ultrasound might be considered if urine testing is not supportive of infection. Cystoscopic-guided laser ablation was a successful minimally invasive treatment in this case.

Multicenter retrospective evaluation of transmural migration of subcutaneous ureteral bypass devices within the digestive tract in cats.

BACKGROUND: Placement of a subcutaneous ureteral bypass (SUB) device is an effective method to relieve all causes of ureteral obstruction in cats. Complications involving migration within the gastrointestinal tract have been seldomly described. OBJECTIVES: To characterize transmural migration of SUB devices within the digestive tract in cats. ANIMALS: Eleven migrated SUB catheters identified in 8 cats between 2017 and 2021. METHODS: Retrospective review of medical records of cats with a SUB device in which migration into the gastrointestinal tract was identified. RESULTS: The median time from SUB device placement to implant migration was 928 days (201-2298 days). Seven cats had obstruction of the SUB device and a positive urine culture at diagnosis. The migration was identified by ultrasound in 6/11, pre-operative contrast radiography in 2/2, and only at time of surgery in 3 SUB devices. All cats underwent surgical correction. Four nephrostomy and 7 cystotomy catheters migrated. Migration occurred into the duodenum (3/11), jejunum (7/11), and colon (1/11). SUB devices were removed in 7 cats and replaced in 2 cats, with 1 cat diagnosed with 2 migration events. Gastrointestinal resection and anastomosis were performed in 7/8 cats and an enterotomy in 2 cats. Six cats survived to discharge. The median follow-up time after migration diagnosis was 365 days (range, 0-1114 days) and 2 cats are still alive. CONCLUSIONS AND CLINICAL IMPORTANCE: Although a rare complication, migration of SUB device should be considered in cats with SUB device obstruction and a positive urine culture.

Use of indwelling, double-pigtail stents for treatment of malignant ureteral obstruction in dogs: 12 cases (2006-2009).

OBJECTIVE: To determine the outcome of minimally invasive ureteral stent placement for dogs with malignant ureteral obstructions. DESIGN-Retrospective case series. ANIMALS: 12 dogs (15 ureters) with ureteral obstruction secondary to a trigonal urothelial carcinoma. PROCEDURES: In all patients, indwelling, double-pigtail ureteral stents were placed by means of percutaneous antegrade needle and guide wire access under ultrasound and fluoroscopic guidance. RESULTS: Stents were successfully placed in all patients. In 11 of 12 patients, percutaneous antegrade access was accomplished. One patient required access via laparotomy because percutaneous access could not be achieved. The median survival time from the date of diagnosis was 285 days (range, 10 to 1,571 days), with a median survival time of 57 days (range, 7 to 337 days) from the date of stent placement. Three complications occurred in 1 patient. Seven patients required concurrent urethral stent placement for relief of urethral obstruction. All animals were discharged from the hospital (median hospitalization time after stent placement, 18 hours [range, 4 hours to 7 days]) with an indwelling, double-pigtail ureteral stent (3 bilateral and 9 unilateral) in place. All stents evaluated 0.25 to 11 months after placement were considered patent. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that ureteral stent placement was safe, effective, and well tolerated in patients with malignant ureteral obstructions. Stents could be reliably placed in a minimally invasive manner and remain patent long-term. Ureteral stent placement should be considered as early as possible in patients with neoplasia, prior to the development of permanent renal damage.

Dominant outflow vein occlusion in the management of naturally occurring peripheral arteriovenous anomalies in cats and dogs.

Two dogs and 1 cat were referred to a tertiary veterinary center for the consultation and treatment of limb edema, variable dermal sanguineous crusting lesions, and intermittent lameness. A peripheral arteriovenous anomaly (PAA) was diagnosed via computed tomographic angiography (CTA) in each case. Arteriography enabled further evaluation of the PAA with confirmation of a dominant outflow vein. Dominant outflow vein occlusion was achieved by direct ligation in 1 dog and retrograde transvenous glue embolization in the cat and other dog. Repeat arteriography demonstrated resolution of arteriovenous shunting. Presenting clinical signs resolved in all animals. The previously identified aberrant vessels in 1 dog were not identified after CTA 40 days postoperatively. No postoperative complications or recurrence was identified in any case during the 6- to 55-month follow-up period.