OBJECTIVE:To describe the surgical technique and clinical outcome of minimally invasive parathyroidectomy for primary hyperparathyroidism (PHPT) in the dog.ANIMALS:Fifty client-owned dogs with PHPT that underwent minimally invasive parathyroidectomy.STUDY DESIGN:Retrospective cohort study.METHODS:An ultrasound-guided mini lateral approach was made via a plane established between the sternocephalicus muscle and sternohyoideus muscles to expose the thyroid gland and enlarged parathyroid gland. Abnormal parathyroid glands were removed en bloc via partial thyroidectomy. The technique for bilateral disease was similar, the skin incision was made on midline and moved laterally to develop the above-mentioned plane of dissection. Age, sex, breed, bodyweight, ultrasound findings, histopathological diagnosis, surgical time, preoperative clinical signs, and clinical outcome were extracted from the records for descriptive statistics.RESULTS:A total of 62 glands were surgically removed, including 17 hyperplastic glands (17/62, 27.4%), 34 adenomas (34/62, 54.8%), and two carcinomas (2/62, 3.2%). Hypercalcemia resolved shortly after surgery in 44 dogs (44/45, 97.8%). One dog had recurrent hypercalcemia (1/45, 2.2%), one dog had persistent hypercalcemia (1/45, 2.2%), two dogs had permanent hypocalcemia requiring life-long calcitriol supplementation (2/45, 4.4%), and one dog died from clinical hypocalcemia (1/45, 2.2%).CONCLUSION:Minimally invasive parathyroidectomy was associated with a low morbidity and led to favorable outcomes in 44/45 dogs in this series.CLINICAL SIGNIFICANCE:The results of this study supports the use of minimally invasive parathyroidectomy to treat PHPT in dogs.

OBJECTIVETo determine the dominant arterial supply to the scrotum.STUDY DESIGNExperimental anatomic study.ANIMALSIntact male canine cadavers (n = 10).METHODSBarium sulfate was injected into the internal iliac artery (n = 7) or into the pudendoepigastric trunk (n = 3). The perineal, scrotal, and prescrotal skin was sharply dissected from cadavers and radiographed. Angiograms were subjectively reviewed by 3 investigators.RESULTSAngiograms were completed successfully in all 10 dogs, with no difference between frozen and fresh cadavers. The dominant blood supply to the scrotum was consistently identified as arising from the ventral perineal arteries, originating from the internal pudendal arteries, coursing ventrally and cranially toward the caudal scrotum before terminating as the dorsal scrotal arteries (n = 7). The blood supply to the cranial scrotum was more limited (n = 3) as only the cranial border of the scrotum was perfused by the ventral scrotal arteries.CONCLUSIONBased on this anatomic perfusion study, the dorsal scrotal arteries appear to supply a larger area than the ventral scrotal arteries.CLINICAL SIGNIFICANCEThese results provide evidence to justify further consideration of a scrotal flap using the caudal perineal skin as the main cutaneous pedicle to reconstruct defects located on the caudal, medial, and lateral thighs in dogs. Such a flap should be based on the caudal blood supply and the base of this flap should be located caudal to the scrotum to preserve its main blood supply.

OBJECTIVE:To report the use of a balloon catheter as an extraction device for a posthepatic caval thrombus in a dog with a right adrenal tumor.ANIMALS:Twelve-year-old male neutered Chihuahua mix dog.STUDY DESIGN:Case report METHODS: The dog presented for the evaluation of a hepatic mass. Computed tomography of thorax and abdomen was performed, and a right lateral liver lobe mass and a right adrenal mass were noted. The adrenal mass had a caval thrombus extending almost to the level of the right atrium. Traditional methods of tumor thrombectomy were unsuccessful. Extraction of the thrombus was facilitated by passing a balloon catheter through the caudal vena cavotomy until it was cranial to the thrombus, inflating the balloon and slowly withdrawing the catheter.RESULTS:A malignant pheochromocytoma was diagnosed on histology. The dog had a subjectively assessed good quality of life until it was euthanized 118 days postoperatively for acute dyspnea.CONCLUSION:Balloon catheter-assisted thrombectomy was successful in removing an extensive caval thrombus that was otherwise difficult to extract via conventional methods. This technique can be considered in cases with extensive tumor thrombus either as a method of choice or when other methods of thrombus extraction have failed.

OBJECTIVETo evaluate the angiosomes of the superior and inferior labial arteries in the cat and describe the use of a musculomucosal axial pattern flap incorporating each artery for reconstruction of palatal defects in cats.STUDY DESIGNCadaveric study and a series of two clinical cases.SAMPLE POPULATIONFive feline cadavers and two client-owned cats.METHODSThe common carotid arteries of five feline cadavers were injected with barium sulfate. Radiographs of excised tissue specimens were examined to map the location of the superior and inferior labial arteries and to visualize each angiosome available for an axial pattern flap. Labial musculomucosal flaps were utilized to reconstruct palatal defects in two live cats.RESULTSThe superior and inferior labia were predominantly perfused by the superior and inferior labial arteries, respectively, and the angiosome of each artery encompassed the majority of its respective labium. Comparative positive contrast angiograms revealed the vascular supply was located within the musculomucosal layer. Reconstruction of recurrent palatal defects utilizing musculomucosal flaps based on these angiosomes in two clinical cases was successful with complete survival of the flaps.CONCLUSIONThe upper and lower lips were found to have robust vascular supplies within the musculomucosal layer which can support musculomucosal axial pattern flaps.CLINICAL SIGNIFICANCEThis information provides the veterinary surgeon with additional surgical options for reconstruction of central and caudal palatal defects in the cat.

Objective To describe the location of the dorsal perineal artery in cats and identify landmarks for axial pattern flaps based on this vessel. Study design Anatomic study. Animals Twelve feline cadavers. Methods Nonselective barium sulfate angiography was performed via injection of the descending aorta. Skin excised from the perineum and thighs was evaluated via gross inspection and radiography to identify angiosomes. Results The dorsal perineal artery had a robust angiosome on the caudal thigh in 10 of 12 cadavers. The artery exited the ischiorectal fossa along the muscular furrow between the biceps femoris and semitendinosus muscles and passed sagittally toward the popliteal fossa in those 10 specimens. All cadavers had a consistent angiosome based on the ventral perineal artery, which was located on the caudomedial thigh. All cadavers also had a consistent angiosome from a cutaneous branch of the popliteal artery, which traveled in a distal to proximal direction starting at the popliteal fossa. Conclusion The dorsal perineal artery had a large cutaneous angiosome on the caudal thigh, which was consistent in most cats. The ventral perineal artery and cutaneous branch of the popliteal artery had consistent but smaller cutaneous angiosomes. Clinical significance The axial pattern flaps of the cutaneous branches of the dorsal and ventral perineal arteries and the popliteal artery provide a robust arterial blood supply to the skin of the perineum and the caudal thigh. These three flaps may therefore have adequate vascular supply to consistently survive in most cats.

Objective The aim of this study was to evaluate the angiosome of the superior and inferior labial arteries within the superior and inferior labia and to describe superior and inferior labial musculomucosal axial pattern flaps that can be used for intra-oral wound reconstruction. This study also presents the clinical use of a superior labial musculomucosal flap in a dog. Materials and Methods The common carotid arteries of six canine cadavers were injected with barium sulphate. The skin of the face and labial mucosa was removed and radiographed to study the vascular supply of the superior and inferior labia. Results The angiograms in all dogs demonstrated that the superior and inferior labial arteries were located within the musculomucosal layer of the labia. At the junction of the rostral and caudal half of the upper lip, extensive choke anastomoses joined the angiosome of the infra-orbital artery. The inferior labial artery perfused the caudal half of the lower labium and had extensive choke anastomoses with the middle and rostral mental arteries. Clinical Significance The musculomucosal flaps of the superior and inferior labia contain a rich arterial blood supply, which suggests that these flaps may survive in live dogs. The superior labial musculomucosal flap was successfully used to reconstruct a large cleft palate in a single clinical case.

OBJECTIVE:To determine (1) if preoperative and intraoperative osteotomy planning increases the likelihood that a surgeon will achieve a centered osteotomy during tibial plateau leveling osteotomy (TPLO) and (2) if that centered osteotomy reduces the risk of tibial tuberosity (TT) fractures.STUDY DESIGN:Retrospective case series.ANIMALS:Dogs (n = 406) with cranial cruciate ligament that had TPLO (n = 468).METHODS:Medical records (2007-2010) and radiographs of dogs that had TPLO were reviewed. Osteotomies from Group A (pre and intra-operative planning) were compared to Group B (free-hand osteotomy only) investigating the influence of osteotomy planning as well as 21 other variables, looking for any other confounding variables that may also contribute to TT fractures. Data were analyzed with logistic regression and χ(2) analysis.RESULTS:Actual osteotomies were closer to the centered-osteotomy position in Group A than in Group B (P ≤ .01). TT fractures occurred in 20 cases (4.3% overall). Group A had 0 fractures out of 172 surgeries and Group B had 20 fractures out of 296 surgeries (6.8%). Five variables were found to increase the risk of TT fractures: lack of osteotomy planning, bilateral same-session surgeries, osteotomy gap, anti-rotational pin location, and decreased tibial crest width at the insertion of the patellar ligament (P ≤ .05).CONCLUSIONS:Dogs that had osteotomy planning had a more centered osteotomy position and a reduced risk of developing TT factures.

OBJECTIVE To (1) compare thickness of the epidermis and dermis of anatomically different donor sites in dogs, and (2) evaluate hair follicle damage during full thickness skin grafts (FTSG) preparation from anatomically different donor sites. Another objective was to compare the extent of agreement between gross and histologic quality of graft preparation. STUDY DESIGN Ex vivo study. ANIMALS Healthy Beagle dogs (n = 12). METHODS Skin samples were harvested from fresh cadavers free of gross dermatopathology and FTSG prepared. Regional, epidermal and dermal thickness, and hair follicle density in intact skin and FTSG specimens from different regions were determined by histomorphometric analysis. Hair follicle density in intact skin and FTSG specimens, and skin thickness measurements were compared among regions. RESULTS Mean epidermis and dermis thickness of the dorsal lumbar and lateral neck regions were significantly greater when compared with other sites. Total hair follicle (superficial and deep dermis) densities were significantly less in prepared FTSG versus intact skin specimens. The dorsal lumbar region had the highest hair follicle density. CONCLUSIONS Thickness of the epidermis and dermis is dependent on body region. Hair follicle density in the FTSG specimens was decreased compared with intact skin specimens, which may affect hair regrowth in FTSG.

Chapter 44 Liver Lobe Torsion and Abscess Daniel A. Degner, Daniel A. DegnerSearch for more papers by this authorJitender Bhandal, Jitender BhandalSearch for more papers by this author Daniel A. Degner, Daniel A. DegnerSearch for more papers by this authorJitender Bhandal, Jitender BhandalSearch for more papers by this author Book Editor(s):Professor, Small Animal Surgery Eric Monnet DVM, PhD, FAHA, Diplomate ACVS, ECVS, Professor, Small Animal Surgery Eric Monnet DVM, PhD, FAHA, Diplomate ACVS, ECVS Colorado State University, ColoradoSearch for more papers by this author First published: 21 December 2012 https://doi.org/10.1002/9781118997505.ch44 AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onFacebookTwitterLinked InRedditWechat Summary Liver lobe torsion is a rare condition, but has been reported in dogs, cats, horses, pigs, rabbits, otters, and humans. Torsion of one liver lobe from any division results in strangulation of vessels of the torsed lobe, which may lead to infarction and necrosis. Most often a single lobe is affected; however, simultaneous torsion of two liver lobes or the entire liver is reported in domestic animals and humans. The liver lobes are suspended by their attachments to the diaphragm and body wall by a number of ligaments. Liver abscesses are uncommon in dogs and cats. Clinical signs common to liver abscessation include lethargy, anorexia, vomiting, diarrhea, trembling, abdominal pain, fever, and dehydration. Aspiration of a liver lesion and cytology of the exudate is essential for confirming a diagnosis of liver abscess. Potential complications of drainage of liver abscesses may include abscess rupture with localized or generalized peritonitis. Small Animal Soft Tissue Surgery RelatedInformation

The objective of this retrospective study was to compare vascularized free or roll-in ulnar bone grafts for limb-sparing surgery in dogs with radial osteosarcoma with the cortical allograft, metal endoprosthesis, or distraction osteogenesis techniques. Overall, the ulnar graft techniques used in this study demonstrated excellent healing properties. Complications included recurrence of the tumor in 25% (2/8) of the dogs, metastasis in 50% (4/8) of the dogs, implant loosening in 37.5% (3/8) of the dogs, implant failure in 12.5% (1/8) of the dogs, and infection in 62.5% (5/8) of the dogs. Mean survival time was 29.3 mo (range, 9 to 61 mo). The mean metastasis-free interval was 33.67 mo (range, 8 to 54 mo). Tumors recurred locally in two dogs at 10 mo and 20 mo postoperatively. This study yielded similar long-term complications as other limb-sparing options (such as cortical allografts and metal endoprostheses) and allowed dogs to bear weight on the operated limb with acceptable limb function. More research is needed regarding specific healing times for ulnar vascularized grafts, time until implant removal, and the extent of radial bone that could ultimately be replaced by the ulna.

OBJECTIVE:To describe hepatic vasculobiliary anatomy important to hilar liver lobe resection in the dog.STUDY DESIGN:Experimental study.ANIMALS:Canine cadavers (n=7).METHODS:The vasculobiliary system of 7 fresh canine livers was injected with a polymer. The parenchyma was dissected at the level of the hilus to determine the vascular and biliary supply to each liver lobe, and then macerated with a corrosion preparation. The information gathered was used to describe a surgical approach for hilar liver lobe resection.RESULTS:Each liver lobe had a single hepatic artery and biliary duct. The location of these structures was consistent, although minor variations existed (dorsal versus ventral to the lobar portal vein) in the left lateral lobe and papillary process in 2 specimens. Most liver lobes (34/49) were supplied by 1 lobar portal vein and drained by 1 lobar hepatic vein (39/49). The location of the portal and hepatic veins was consistent among specimens.CONCLUSIONS:The left division is the most mobile of the liver lobes and each lobe can be removed separately or en bloc. Because of the location of the hepatic veins, the central division is best removed as a single unit. The right lateral lobe can be removed individually or together with the caudate process. The papillary process is removed by itself.CLINICAL RELEVANCE:A hilar liver lobectomy technique can provide an alternative approach to conventional procedures for tumors that encroach upon the hilus of the liver.

OBJECTIVE:To evaluate the clinical use and outcome of a rectus abdominis microvascular free flap for wound closure in dogs.STUDY DESIGN:Retrospective case series.ANIMALS:Dogs (n=9) with complex extremity or oral wounds.METHODS:Medical records (2002-2006) of dogs that had a rectus abdominis free tissue transfer to close an extremity or oral wound were reviewed.RESULTS:Nine dogs were identified: 5 had distal extremity wounds, 3 had oral palatal defects, and 1 had a large hygroma excised. A rectus abdominis free tissue transfer with a caudal epigastric vascular pedicle was successfully used for management of these wounds. No major complications occurred with the donor site and a good cosmetic and functional outcome occurred in all dogs.CONCLUSION:The rectus abdominis is a versatile muscle that can be used for reconstructing cutaneous and oral defects with repeatable success.CLINICAL RELEVANCE:Free tissue transfer of the rectus abdominis muscle is a clinically useful technique for closure of a variety of difficult soft tissue wounds.

Elbow luxation is a common orthopedic injury in the ferret. The injury is usually caused by trauma but can also occur spontaneously. The most successful treatment involves a combination of surgical and medical intervention. Surgical treatment includes open reduction of the elbow joint and stabilization with orthopedic implants. Medical treatment includes external coaptation, analgesia, and prevention of infection. Owner compliance also plays an important role in return to full function of the luxated ferret elbow joint.