Jane F. Ladlow

Injection site-associated sarcoma in the cat: treatment recommendations and results to date.

Practical relevance: Feline injection site-associated sarcomas (FISSs) have been the cause of much controversy and concern since they were first reported in the early 1990s. While not solely associated with vaccination, there are implications for vaccination sites and schedules and, while guidance has been published, this appears to be permeating only slowly through to general practice. Clinical challenges: Up to one-quarter of cats with this difficult condition have metastatic lung involvement. The mainstay of treatment is aggressive surgery, but even in cases where full excision with clean margins is achieved, tumour recurrence is anticipated in about one-third of cases. The role of radiotherapy and chemotherapy as adjuvant treatments has yet to be clearly defined. Patient group: FISSs are often seen in younger cats, with a peak presentation at 6–7 years and a second peak at 10–11 years. Evidence base: This review summarises the diagnosis and management of FISS with reference to the latest published treatment results. It focuses on surgical excision but also covers adjuvant radiotherapy and chemotherapy, and gives median survival times for the different treatment approaches.

Characterisation of Brachycephalic Obstructive Airway Syndrome in French Bulldogs Using Whole-Body Barometric Plethysmography

Brachycephalic obstructive airway syndrome (BOAS) is an important health and welfare problem in several popular dog breeds. Whole-body barometric plethysmography (WBBP) is a non-invasive method that allows safe and repeated quantitative measurements of respiratory cycles on unsedated dogs. Here respiratory flow traces in French bulldogs from the pet population were characterised using WBBP, and a computational application was developed to recognise affected animals. Eighty-nine French bulldogs and twenty non-brachycephalic controls underwent WBBP testing. A respiratory functional grading system was used on each dog based on respiratory signs (i.e. respiratory noise, effort, etc.) before and after exercise. For development of an objective BOAS classifier, functional Grades 0 and I were considered to have insignificant clinical signs (termed here BOAS-) and Grades II and III to have significant signs (termed here BOAS+). A comparison between owner-perception of BOAS and functional grading revealed that 60 % of owners failed to recognise BOAS in dogs that graded BOAS+ in this study.WBBP flow traces were found to be significantly different between non-brachycephalic controls and Grade 0 French bulldogs; BOAS- and BOAS+ French bulldogs. A classifier was developed using quadratic discriminant analysis of the respiratory parameters to distinguish BOAS- and BOAS + French bulldogs, and a BOAS Index was calculated for each dog. A cut-off value of the BOAS Index was selected based on a receiver operating characteristic (ROC) curve. Sensitivity, specificity, positive predictive value, and negative predictive value of the classifier on the training group (n=69) were 0.97, 0.93, 0.95, and 0.97, respectively. The classifier was validated using a test group of French bulldogs (n=20) with an accuracy of 0.95. WBBP offers objective screening for the diagnosis of BOAS in French Bulldogs. The technique may be applied to other brachycephalic breeds affected by BOAS, and possibly to other respiratory disease in dogs.

Whole-Body Barometric Plethysmography Characterizes Upper Airway Obstruction in 3 Brachycephalic Breeds of Dogs

Background A novel test using whole‐body barometric plethysmography (WBBP) was developed recently to diagnose brachycephalic obstructive airway syndrome (BOAS) in unsedated French bulldogs. Hypothesis/Objectives The hypotheses of this study were: (1) respiratory characteristics are different between healthy nonbrachycephalic dogs and brachycephalic dogs; and among pugs, French bulldogs, and bulldogs; and (2) obesity and stenotic nares are risk factors for BOAS. The main objective was to establish a diagnostic test for BOAS in these 3 breeds. Animals A total of 266 brachycephalic dogs (100 pugs, 100 French bulldogs, and 66 bulldogs) and 28 nonbrachycephalic dogs. Methods Prospective study. Exercise tolerance tests with respiratory functional grading, and WBBP were performed on all dogs. Data from WBBP were associated with functional grades to train quadratic discriminant analysis tools to assign dogs to BOAS+ and BOAS‐ groups. A BOAS index (0–100%) was calculated for each dog. Receiver operating characteristic (ROC) curves were used to evaluate classification ability. Results Minute volume was decreased significantly in asymptomatic pugs (P = .009), French bulldogs (P = .026), and bulldogs (P < .0001) when compared to nonbrachycephalic controls. Respiratory characteristics were different among breeds and affected dogs had a significant increase in trace variation. The BOAS index predicted BOAS status for each breed with 94–97% (95% confidence interval [CI], 88.9–100%) accuracy (area under the ROC curve). Both obesity (P = .04) and stenotic nares (P = .004) were significantly associated with BOAS. Conclusions and Clinical Importance The WBBP can be used as a clinical tool to diagnose BOAS noninvasively and objectively.

Comparison of surgical duration of canine ovariectomy and ovariohysterectomy in a veterinary teaching hospital

OBJECTIVE To prospectively evaluate ovariectomy and ovariohysterectomy via midline coeliotomy when being employed by supervised final year veterinary students for the purpose of routine canine neutering. METHODS One hundred and eight female dogs of various breeds, presented to a veterinary teaching hospital for neutering, were randomly allocated to one of two surgery groups, ovariectomy or ovariohysterectomy. The specified procedure was performed by a supervised final year veterinary student. If the duration of surgery exceeded 2 hours or if major surgical or anaesthetic complications occurred, the supervising surgeon intervened to complete the procedure. RESULTS Data analysed included age, weight, time from first incision to start of closure, duration of closure, total surgical time and length of incision. Fifty-four dogs underwent each procedure. There was no significant difference between the two surgery groups for any of the measured variables. CLINICAL SIGNIFICANCE Ovariectomy is not associated with shorter surgical times or smaller abdominal incisions than ovariohysterectomy when employed by inexperienced surgeons. As no major complications novel to ovariectomy occurred in this cohort of dogs, this study adds support to the existing literature indicating that ovariectomy is an acceptable alternative to ovariohysterectomy for canine neutering.

Creation of a Urethral Conduit from a Preputial Indirect Flap in a Dog with Perineal Hypospadias

OBJECTIVE To report a surgical technique for creation of a urethral conduit using a preputial indirect flap. STUDY DESIGN Case report. ANIMALS Male Doberman Pinscher (6 weeks old). METHODS A urethral conduit was constructed using a multistage preputial indirect flap in a dog with severe perineal hypospadias. RESULTS Successful transfer of a perineal located urethral meatus to a more anatomically normal inguinal location was achieved with a preputial flap. The procedure was performed to aid control of recurrent urinary tract infections after anal and urethral separation in a dog with imperforate anus, urethrorectal fistula, and proximal perineal hypospadias. CONCLUSIONS Creation of a urethral conduit from a tubed bipedicle flap using redundant preputial tissue eliminated fecal contamination of the urethral meatus, aiding control of urinary tract infection. A good functional and cosmetic outcome was achieved. CLINICAL RELEVANCE This technique should be considered in aiding control and prevention of urinary tract infections in dogs with proximal perineal hypospadias where a preputial remnant exists.

Conformational risk factors of brachycephalic obstructive airway syndrome (BOAS) in pugs, French bulldogs, and bulldogs.

Extremely brachycephalic, or short-muzzled, dog breeds such as pugs, French bulldogs, and bulldogs are prone to the conformation-related respiratory disorder—brachycephalic obstructive airway syndrome (BOAS). Affected dogs present with a wide range of clinical signs from snoring and exercise intolerance, to life-threatening events such as syncope. In this study, conformational risk factors for BOAS that could potentially aid in breeding away from BOAS were sought. Six hundred and four pugs, French bulldogs, and bulldogs were included in the study. Soft tape measurements of the head and body were used and the inter-observer reproducibility was evaluated. Breed-specific models were developed to assess the associations between the conformational factors and BOAS status based on functional grading. The models were further validated by means of a BOAS index, which is an objective measurement of respiratory function using whole-body barometric plethysmography. The final models have good predictive power for discriminating BOAS (-) and BOAS (+) phenotypes indicated by the area under the curve values of >80% on the receiver operating curves. When other factors were controlled, stenotic nostrils were associated with BOAS in all three breeds; pugs and bulldogs with higher body condition scores (BCS) had a higher risk of developing BOAS. Among the standardized conformational measurements (i.e. craniofacial ratio (CFR), eye width ratio (EWR), skull index (SI), neck girth ratio (NGR), and neck length ratio (NLR)), for pugs EWR and SI, for French bulldogs NGR and NLR, and for bulldogs SI and NGR showed significant associations with BOAS status. However, the NGR in bulldogs was the only significant predictor that also had satisfactory inter-observer reproducibility. A NGR higher than 0.71 in male bulldogs was predictive of BOAS with approximately 70% sensitivity and specificity. In conclusion, stenotic nostrils, BCS, and NGR were found to be valid, easily applicable predictors for BOAS (+).

Canine Intrahepatic Vasculature: Is a Functional Anatomic Model Relevant to the Dog?

Objective To clarify canine intrahepatic portal and hepatic venous system anatomy using corrosion casting and advanced imaging and to devise a novel functional anatomic model of the canine liver to investigate whether this could help guide the planning and surgical procedure of partial hepatic lobectomy and interventional radiological procedures. Study Design Prospective experimental study. Animals Adult Greyhound cadavers (n = 8). Methods Portal and hepatic vein corrosion casts of healthy livers were assessed using computed tomography (CT). Results The hepatic lobes have a consistent hilar hepatic and portal vein supply with some variation in the number of intrahepatic branches. For all specimens, 3 surgically resectable areas were identified in the left lateral lobe and 2 surgically resectable areas were identified in the right medial lobe as defined by a functional anatomic model. Conclusions CT of detailed acrylic casts allowed complex intrahepatic vascular relationships to be investigated and compared with previous studies. Improving understanding of the intrahepatic vascular supply facilitates interpretation of advanced images in clinical patients, the planning and performance of surgical procedures, and may facilitate interventional vascular procedures, such as intravenous embolization of portosystemic shunts. Functional division of the canine liver similar to human models is possible. The left lateral and right medial lobes can be consistently divided into surgically resectable functional areas and partial lobectomies can be performed following a functional model; further study in clinically affected animals would be required to investigate the relevance of this functional model in the dog.OBJECTIVE To clarify canine intrahepatic portal and hepatic venous system anatomy using corrosion casting and advanced imaging and to devise a novel functional anatomic model of the canine liver to investigate whether this could help guide the planning and surgical procedure of partial hepatic lobectomy and interventional radiological procedures. STUDY DESIGN Prospective experimental study. ANIMALS Adult Greyhound cadavers (n = 8). METHODS Portal and hepatic vein corrosion casts of healthy livers were assessed using computed tomography (CT). RESULTS The hepatic lobes have a consistent hilar hepatic and portal vein supply with some variation in the number of intrahepatic branches. For all specimens, 3 surgically resectable areas were identified in the left lateral lobe and 2 surgically resectable areas were identified in the right medial lobe as defined by a functional anatomic model. CONCLUSIONS CT of detailed acrylic casts allowed complex intrahepatic vascular relationships to be investigated and compared with previous studies. Improving understanding of the intrahepatic vascular supply facilitates interpretation of advanced images in clinical patients, the planning and performance of surgical procedures, and may facilitate interventional vascular procedures, such as intravenous embolization of portosystemic shunts. Functional division of the canine liver similar to human models is possible. The left lateral and right medial lobes can be consistently divided into surgically resectable functional areas and partial lobectomies can be performed following a functional model; further study in clinically affected animals would be required to investigate the relevance of this functional model in the dog.

IMAGING DIAGNOSIS-EXTRAHEPATIC BILIARY TRACT OBSTRUCTION SECONDARY TO A BILIARY FOREIGN BODY IN A CAT: Imaging Diagnosis-Obstructive Biliary Foreign Body In A Cat

An 11-year-old, neutered female British Shorthair cat was referred with a 4-week history of abdominal pain and vomiting. Abdominal ultrasonography revealed a dilated common bile duct containing a spindle-shaped structure with several reflecting interfaces. Differentials that were considered included an intraluminal foreign body, or helminth parasites within the common bile duct. Surgical exploration of the abdominal cavity demonstrated the presence of two grass awns obstructing the common bile duct. Anomalies of the portal vasculature were noted during surgery and were considered an incidental finding. The clinical signs resolved following surgical removal of the grass awns.

Endotracheal tube placement during computed tomography of brachycephalic dogs alters upper airway dimensional measurements

Computed tomography (CT) is used to document upper airway lesions in dogs with brachycephalic obstructive airway syndrome. The presence of an endotracheal tube during CT scanning is often required for general anesthesia. We hypothesized that the endotracheal tube placement would change the soft tissue dimensions of the upper airway. The aims of this prospective, method comparison study were to evaluate the reliability of the previously reported upper airway CT measurements with endotracheal tube placement, and to propose measurements that are minimally affected by the endotracheal tube. Twenty brachycephalic dogs were included in this study. Each dog underwent head/neck CT with an endotracheal tube, followed by a second scan without the endotracheal tube. Ten measurements of the soft palate, nasopharynx, and trachea were performed. Tracheal dimension was significantly larger with the endotracheal tube compared to without, whereas the soft palate cross-sectional area was significantly smaller with the endotracheal tube than without the endotracheal tube. The influence of the endotracheal tube on the caudal nasopharynx cross-sectional (transverse-sectional) area varied with a mean proportional absolute difference of 35%. Rostral soft palate thickness, tracheal perimeter, and cross-sectional area of the rostral nasopharynx were the measurements least affected by the endotracheal tube (intraclass correlation coefficient = 0.964, 0.967, and 0.951, respectively). Therefore, we proposed that these three measurements may be most useful for future brachycephalic obstructive airway syndrome studies that require CT scanning of intubated animals. However, with endotracheal tube placement, measurements of soft palate length, caudal nasopharyngeal cross-sectional area, and trachea height and width may not be reliable.

Objective effectiveness of and indications for laser-assisted turbinectomy in brachycephalic obstructive airway syndrome

OBJECTIVE To evaluate the effectiveness of laser-assisted turbinectomy (LATE) in treating brachycephalic obstructive airway syndrome (BOAS) and to investigate the potential indications. STUDY DESIGN Prospective clinical study. SAMPLE POPULATION Client-owned pugs, French bulldogs, and English bulldogs (n = 57). METHODS A BOAS index was obtained from whole-body barometric plethysmography before BOAS conventional multilevel surgery (CMS) and 2-6 months post-CMS. Dogs with BOAS index >50% and BOAS functional grades II-III after CMS were considered candidates for LATE. A BOAS index was repeated 2-6 months after LATE. Intranasal lesions and a measurement of soft tissue proportion at the rostral entrance of choanae (STC) were recorded on the basis of computed tomography images. Logistic regressions were used to assess the intranasal predictors for being LATE candidates. RESULTS Twenty-nine of 57 dogs were candidates for LATE, all of which were pugs or French bulldogs. The median BOAS index of dogs that were operated on (20/29 candidates) decreased from 67% post-CMS to 42% after LATE (P < .001). Soft tissue proportion at the rostral entrance of choanae was the only predictor for candidacy for LATE. Pugs (P = .021; cutoff = 64%) and French bulldogs (P = .008; cutoff = 55%) with higher STC were more likely to be candidates for LATE. After LATE, 12 of 20 dogs had temporary episodes of reverse sneezing, and nasal noise was noted in 8 of 20 dogs when sniffing and excited. CONCLUSION Laser-assisted turbinectomy was an effective treatment for dogs with intranasal abnormalities and a poor response to CMS. Soft tissue proportion at the rostral entrance of choanae was a predictor of candidacy for LATE in pugs and French bulldogs. CLINICAL SIGNIFICANCE Computed tomography-based measurement of STC can be used to predict whether LATE is required in addition to CMS in pugs and French bulldogs with BOAS.