Ana V. Cáceres

Feline Ureteral Strictures: 10 Cases (2007–2009)

BACKGROUND Feline ureteral obstructions have emerged as a common problem. Ureteral strictures rarely are reported as a cause and the predisposing factors and clinical course of this condition have not been described. OBJECTIVES Evaluate cases of feline ureteral strictures and characterize historical features, clinical signs, diagnostic imaging, surgical and endoscopic findings, histopathology, treatment modalities, and short- and long-term outcomes. ANIMALS Ten cats diagnosed with ureteral strictures based on compatible findings from at least 2 of the following: ultrasonography, ureteropyelography, surgical exploration, or histopathology. METHODS Retrospective study. RESULTS Median age, serum creatinine concentration, and size of the renal pelvis were 12 years, 3.7 mg/dL, and 11.75 mm, respectively. Six of 10 cats had hyperechoic periureteral tissue on ultrasound examination at the stricture site. Four cats had evidence of a circumcaval ureter at surgery. Eight cats had an intervention including ureteral stent placement (n = 6) and traditional surgery (n = 2). Seven of 8 cats had decreases in serum creatinine concentration and renal pelvic parameters preceding discharge and 6 had persistently improved results at their last examination. All patients survived to discharge. Median survival time was > 294 days (range, 14 to > 858 days) with 6/10 cats still alive. CONCLUSIONS AND CLINICAL IMPORTANCE Ureteral strictures may occur in cats secondary to ureteral surgery, inflammation, a circumcaval ureter, impacted ureterolithiasis, or for unknown causes. With appropriate and timely intervention, the prognosis for long-term survival is good. In addition to ureteral reimplantation or ureteronephrectomy, ureteral stenting or SC ureteral bypass may be considered as future therapeutic options.

Multiple myeloma in 16 cats: a retrospective study

Background: There is limited published information regarding feline multiple myeloma. Diagnostic criteria are derived from canine studies and to our knowledge, have not been critically reviewed for cats. Objective: To evaluate the clinical and laboratory findings in cats with multiple myeloma and appraise diagnostic criteria. Methods: Retrospective evaluation of medical records was performed. Inclusion required an antemortem diagnosis of multiple myeloma using 2 of 4 criteria: 1) ≥20% plasma cells in the bone marrow, or ≥10% if atypical plasma cells; 2) paraproteinemia; 3) radiographically‐evident osteolysis; 4) light chain proteinuria. Alternatively, a postmortem diagnosis was based on the findings of multiple plasma cell neoplasms, with marrow involvement. Results: Sixteen cats were diagnosed with multiple myeloma between 1996 and 2004, with a median age of 14.0 years; 9 of 16 (56%) were castrated males, and 7 of 16 (44%) were spayed females. Laboratory abnormalities included hyperglobulinemia (14/16, 87.5%), with 11/14 (78.5%) monoclonal and 3/14 (21.4%) biclonal gammopathies; hypoalbuminemia (4/16, 25%); light chain proteinuria, (4/9, 44.4%); hypocholesterolemia (11/16, 68.7%); hypercalcemia, (3/15, 20%); nonregenerative anemia, (11/16, 68.7%); regenerative anemia, (1/16, 6.2%); neutropenia (5/15, 33.3%); thrombocytopenia (8/16, 50%); and marrow plasmacytosis (14/15, 93.3%). Plasma cells were markedly immature, atypical, or both in 10 of 12 (83.3%) cats. Focal or multifocal osteolysis was noted in 6 of 12 (50%) cats for which radiographs were available for review; generalized osteopenia was found in 1 (8.3%) cat. Noncutaneous, extramedullary tumors were found in all cats assessed, 7/7 (100%), including spleen (6), liver (3), and lymph nodes (4). The disease in 1 of 2 cats with cutaneous tumors progressed to plasmacytic leukemia. Conclusions: Common findings in feline multiple myeloma include atypical plasma cell morphology, hypocholesterolemia, anemia, bone lesions, and multi‐organ involvement. Based on the results of this study, we advocate modifying diagnostic criteria in cats to include consideration of plasma cell morphology and visceral organ infiltration.

COMPARISON BETWEEN BOLUS TRACKING AND TIMING-BOLUS TECHNIQUES FOR RENAL COMPUTED TOMOGRAPHIC ANGIOGRAPHY IN NORMAL CATS

Renal dual-phase computed tomograpic angiography (CTA) is used to assess suitability of feline donors prior to transplantation. A prerequisite for successful CTA is optimal synchronization between the arterial passage of contrast material and CT data acquisition. This retrospective study was conducted to compare quality of renal vascular enhancement at dual-phase CTA in normal cats between two techniques of timing of data acquisition: the timing-bolus and the bolus tracking method. Nine cats were scanned using the timing-bolus technique and 14 with the bolus tracking technique using otherwise similar scanning parameters in a 16-slice multidetector row CT scanner. The quality of enhancement of the renal vessels at the scanned arterial phase and venous phase was assessed both subjectively and objectively by three board-certified radiologists. Arterial enhancement was not observed at the scanned arterial phase in three of the nine cats with the timing-bolus technique but only 1 of the 14 cats with the bolus tracking technique. Early venous enhancement at the scanned arterial phase was common with the bolus tracking technique. Data acquisition was significantly faster with the bolus tracking technique. We conclude that the bolus tracking technique is a valid technique that could be integrated into the routine protocol for 16-detector row CT renal angiography in cats.

RELIABILITY OF T2‐WEIGHTED SAGITTAL MAGNETIC RESONANCE IMAGES FOR DETERMINING THE LOCATION OF COMPRESSIVE DISk HERNIATION IN DOGS

Magnetic resonance imaging is used commonly to diagnose intervertebral disk herniation in dogs. It is common to locate areas of suspected compression on sagittal T2-weighted (T2-W) images and then obtain limited transverse images in these areas to reduce the acquisition time (a step-by-step approach). Our objective was to assess the frequency of correct localization of spinal cord compression due to disk herniation using only the sagittal images. The results from isolated readings of the sagittal T2-W images alone or combined with a single-shot fast spin echo (SSFSE) slab in 118 dogs were compared with a gold standard, based on a consensual reading of all images available, including complete transverse images across the entire spinal segments under study. The sites of compression were localized correctly from the sagittal images in 89.8% of dogs. If only the most significant lesions were accounted for, the percentage increased up to 95.2%. In 54.9% of the readings with incorrect localization, the actual compressive site was immediately adjacent to the one suspected from review of the sagittal images. The frequency of correct localization was higher in the cervical region, and was increased by examination of the SSFSE slab. The most common cause of disagreement was the presence of multiple degenerate bulging disks. Based on these results we recommend obtaining transverse images across the entire segment when multiple bulging disks are present. It is also recommended to obtain transverse images across the spaces immediately adjacent to the suspected site of herniation from review of the sagittal images.

Sensitivity, positive predictive value, and interobserver variability of computed tomography in the diagnosis of bullae associated with spontaneous pneumothorax in dogs: 19 cases (2003–2012)

OBJECTIVE To determine the sensitivity, positive predictive value, and interobserver variability of CT in the detection of bullae associated with spontaneous pneumothorax in dogs. DESIGN Retrospective case series. ANIMALS 19 dogs with spontaneous pneumothorax caused by rupture of bullae. PROCEDURES Dogs that had CT for spontaneous pneumothorax caused by rupture of bullae confirmed at surgery (median sternotomy) or necropsy were included. Patient signalment, CT protocols, and bulla location, size, and number were obtained from the medical records. Computed tomographic images were reviewed by 3 board-certified radiologists who reported on the location, size, and number of bullae as well as the subjective severity of pneumothorax. RESULTS Sensitivities of the 3 readers for bulla detection were 42.3%, 57.7%, and 57.7%, with positive predictive values of 52.4%, 14.2%, and 8.4%, respectively, with the latter 2 readers having a high rate of false-positive diagnoses. There was good interobserver agreement (κ = 0.640) for correct identification of bullae. Increasing size of the bulla was significantly associated with a correct CT diagnosis in 1 reader but not in the other 2 readers. Correct diagnosis was not associated with slice thickness, ventilation protocol, or degree of pneumothorax. CONCLUSIONS AND CLINICAL RELEVANCE Sensitivity and positive predictive value of CT for bulla detection were low. Results suggested that CT is potentially an ineffective preoperative diagnostic technique in dogs with spontaneous pneumothorax caused by bulla rupture because lesions can be missed or incorrectly diagnosed. Bulla size may affect visibility on CT.

Articular Cartilage Lesions of the Patellofemoral Joint in Dogs With Naturally Occurring Cranial Cruciate Ligament Disease

OBJECTIVE To evaluate frequency, severity, and location of patellofemoral (PF) osteoarthritis (OA) in dogs with naturally occurring cranial cruciate ligament (CCL) disease. STUDY DESIGN Cross-sectional observational study. ANIMALS Dogs (n = 40; stifles, 44). METHODS Stifle arthroscopic video recordings and radiographs were performed. Cartilage pathology was scored at 3 locations (proximal, middle, distal) in the trochlear groove and patella. A radiographic osteoarthrosis and synovial pathology score were assigned. A Kruskal-Wallis test was used to determine if lesion severity varied by site, synovitis, and osteoarthrosis, and the Dunns test was used for pairwise comparisons. The variability of body weight was evaluated using 1 way ANOVA; P < .05 was considered significant. RESULTS Cartilage pathology and synovitis was identified in all PF joints. The proximal aspect of the trochlear groove had significantly higher cartilage scores than the middle and distal sites and the middle groove site was significantly higher than the distal site. The distal aspect of the patella had significantly greater scores than the middle and proximal patellar locations. Higher synovitis scores were associated with increased cartilage scores. Cartilage scores were significantly greater in stifles with higher radiographic osteophytosis, tibial sclerosis, and patellar enthesiophytosis scores. Higher body weights were significantly associated with greater synovial and radiographic scores. CONCLUSIONS Dogs with CCL disease have a high incidence of PF cartilage pathology and the severity of cartilage lesions varies depending on location within the joint.

Proximal tibial metaphyseal fractures in immature dogs

OBJECTIVE To describe proximal tibial metaphyseal fractures in immature dogs. MATERIALS AND METHODS Medical records of immature dogs with metaphyseal fractures of the proximal tibia were reviewed and data were collected on signalment and history of trauma. Craniocaudal and mediolateral radiographs were evaluated for the determination of the bones fractured, location of the fracture within the bone, fracture configuration, and the presence of fracture segment displacement and angulation. RESULTS Eighteen dogs with 22 proximal tibial metaphyseal fractures fulfilled the inclusion criteria. All fractures had a curvilinear, complete fracture of the proximal tibial metaphysis. Displacement was identified in 16 fractures and angulation in 15 fractures. All affected breeds were terrier or small breed dogs less than six months of age. The majority of dogs weighed less than or equal to 5 kg at the time of injury. The most common type of trauma that occurred was a jump or fall from a short distance. CLINICAL SIGNIFICANCE Proximal tibial metaphyseal fractures are an uncommon injury that occur in skeletally immature dogs from minimal trauma. Proximal tibial metaphyseal fractures have a characteristic curvilinear fracture configuration that affects mainly small breed dogs with a predominance for terrier breeds.

Total laparoscopic gastropexy using 1 simple continuous barbed suture line in 63 dogs

OBJECTIVE To describe the use and outcome of a single, simple continuous, barbed suture line for prophylactic, total laparoscopic gastropexy in dogs. STUDY DESIGN Multi-center, retrospective case series. ANIMALS Sixty-three client-owned dogs. METHODS Medical records of dogs undergoing total laparoscopic gastropexy using a barbed suture at 4 academic veterinary hospitals from 2011-2015 were reviewed. Data collected included signalment, procedure time, procedure-associated complications, short-term complications, and long-term outcome. All procedures were performed under general anesthesia in dorsal to dorsal-left oblique recumbency. Laparoscopic ports were placed on ventral midline in 1 of 3 port configurations, and 5 mm laparoscopic needle drivers were used for intracorporeal sutured gastropexy with unidirectional barbed suture. The gastropexy was positioned just caudal to the 13th rib, 2-4 cm lateral to the rectus abdominis muscle. RESULTS Sixty-three dogs underwent total laparoscopic gastropexy with a single, simple continuous, barbed suture line. Median gastropexy surgery time was 70 minutes (interquartile range [IQR] 60-90 minutes). One dog sustained splenic laceration from Veress needle penetration during initial abdominal insufflation. Short term (>24 hours to 6 months postoperative) complications included incisional seroma formation (n = 2) and suture reaction (n = 1). Long term (>6 months postoperative) complications included intermittent regurgitation and chronic diarrhea in 1 dog. Fifteen dogs had postoperative ultrasound and all had intact gastropexy sites. CONCLUSION Total laparoscopic barbed gastropexy using a single, simple continuous, barbed suture line in dogs is safe and results in an intact gastropexy long term.