Retrospective analysis of perineal herniorrhaphy with cone-shaped polypropylene mesh in dogs: technique description and outcome.

Introduction: This study aimed to describe the technique for the surgical repair of perineal hernia (PH) in dogs using a polypropylene mesh (PM) and to evaluate its outcomes. Methods: All dogs were placed in the Trendelenburg position. Castration and caudal celiotomy for cystopexy and colopexy were performed as needed. Ipsilateral perianal incision was performed in the affected hernia side. A PM was formed a cone-shape with suturing and placed in hernial foramen. The PH was repaired with suturing between PH and pelvic diaphragm including the sacrotuberous ligament, internal obturator muscle, and external anal sphincter muscle. The medical records of all dogs were reviewed to evaluate signalment, perioperative findings, postoperative complications, and prognosis. Results: Of the 22 dogs, 15 were intact, and 7 were previously neutered. The median age and body weight were 10 years and 6.8 kg, respectively. The PH reconstruction using a cone-shaped PM was feasible in all dogs. The median operative time was 60.5 min for unilateral PH and 109 min for bilateral PH. Major postoperative complications occurred in seven dogs (32%), and three dogs (14%) had a recurrence of PH. In the long-term (> 2 weeks) follow-up period, 16 dogs (73%) had an excellent prognosis. Discussion: Our study suggests that PH reconstruction surgery using a cone-shaped PM may be a viable treatment method for PH in dogs. Therefore, a cone-shaped PM could serve as an alternative treatment option for canine PH reconstruction.

Perineal herniorrhaphy with pedunculated tunica vaginalis communis in dogs: Description of the technique and clinical case series.

Background: Perineal hernia (PH) in dogs is caused by the separation of the anal septal muscles and the displacement of pelvic/abdominal organs under the perineal skin. Reconstruction of the pelvic septum by surgical repositioning is the only curative treatment. Objectives: To describe the procedure and outcomes of surgical repair using the pedunculated tunica vaginalis communis (TVC) for PH in dogs. Methods: Intact male dogs diagnosed with PH were included in this study. For surgery, each dog was positioned in the Trendelenburg position. Castration was performed with the open technique, followed by colopexy and cystopexy via laparotomy. The remaining bilateral TVCs transposed to the opening of PH were used for the perineal herniorrhaphy. Intraoperative findings, complications, and outcomes were evaluated and recorded. Results: Eight dogs [median age 10.5 years (range, 9-13 years); median body weight 4.9 kg (range, 1.6-12.3 kg)] were treated using the TVC surgical technique. Perineal herniorrhaphy with the TVC was feasible in all dogs. The median operation time was 105.5 min (range, 46-149 min) in unilateral PH, and 92 and 122 min in two dogs with bilateral PH. Short-term postoperative complications during hospitalization did not occur in six dogs, whereas the residual two dogs had a temporary local infection as a minor complication. Postoperative recurrence occurred in one dog (13%) on postoperative day 136. Conclusions: Our study suggests that the herniorrhaphy technique using the pedunculated TVC is an alternative option for the repair of PH in dogs.

Pharyngeal contraction secondary to its collapse in dogs with brachycephalic airway syndrome.

Brachycephalic airway syndrome (BAS) is a common disease in certain "flat-faced" dog breeds. This syndrome includes stenotic nares, elongated and thickened soft palate, laryngeal collapse, and tracheal hypoplasia. Pharyngeal collapse is also commonly observed, but it is unclear if laryngopharynx motions are merely sequelae or actually contribute to BAS respiratory symptoms. Laryngopharynx motion was imaged using dynamic four-dimensional computed tomography (4D-CT) during spontaneous respiration in four dogs with different BAS types. Dynamic 4D-CT showed laryngopharynx motion in the following order during inspiration: pharyngeal collapse, contraction, and laryngospasm. We concluded that dynamic 4D-CT is a highly-detailed diagnostic approach for detecting laryngopharynx motion. Pharyngeal contraction during inspiration appears to contribute toward the worsening of clinical respiratory signs of BAS.

Impact of intracranial hypertension on the short-term prognosis in dogs undergoing brain tumor surgery.

The present study used data from anesthetic records to analyze variables of intracranial pressure (ICP) during brain tumor surgery or in the early postoperative period as prognostic indicators in dogs. Data from 17 dogs which were scheduled to undergo elective craniotomy for brain tumor surgery from 2009 to 2012 were included. Of these, five (29.4%) died during 14 days after the surgery because of respiratory failure following pneumonia (n=2), euthanasia due to difficulty in treatment of status epilepticus (n=1), tumor-bed hematoma (n=1), and unknown reason (n=1). In the 12 surviving dogs, neurological signs were improved or resolved at discharge. All dogs were administered midazolam and droperidol-fentanyl as premedication. General anesthesia was induced using propofol maintained on isoflurane and oxygen. Direct ICP was obtained via a Codman Microsensor strain gauge transducer. ICP hypertension (>13 mmHg) measured after 15 min of recovery from the moment after discontinuation of anesthesia by turning off the vaporizer dial was associated with poor prognosis (odds ratio, 20.00; 95% confidence interval, 1.39-287.60, P=0.028). This suggests that intracranial pressure influences the postoperative mortality rate in dogs undergoing brain tumor surgery.

Arterial blood gas analysis in dogs with bronchomalacia.

Canine bronchomalacia (CBM) is a structural airway disease leading to chronic cough and intermittent respiratory distress, primarily affecting elderly dogs of small breeds. Results of blood gas analysis have been reported in dogs with several diseases, but not yet in those with CBM. Eleven dogs with CBM were recruited in this study. Most dogs presented with mild hypoxemia and normocapnia, and all with increased alveolar-arterial difference for O2 (A-aDO2). In computed tomography, abnormal lung patterns, such as atelectasis and parenchymal band, were detected in all dogs, consistent with the regions affected by CBM. We conclude that CBM causes abnormal lung patterns and results in impaired oxygenation. Blood gas analysis is a useful tool for detecting mild pulmonary lesions and concurrent CBM.

Surgery for partial atrioventricular septal defect with pulmonary hypertension in an adult dog.

A 4-year-old, 5.9-kg female Japanese Spitz presented with syncope and exercise intolerance. Echocardiography revealed an ostium primum atrial septal defect (ASD), a cleft mitral valve, mitral valve regurgitation (MR), and tricuspid regurgitation (TR) (velocity: 3.6 m/sec, pressure gradient: 52 mmHg), leading to a diagnosis of partial atrioventricular septal defect (AVSD) with moderate pulmonary hypertension (PH). Open-heart surgery using cardiopulmonary bypass was performed through right atriotomy. The cleft of the mitral valve was sutured with polypropylene and the AVSD was closed using an autologous pericardial patch fixed with glutaraldehyde. No postoperative pulmonary hypertensive crisis occurred. Shunting flow through the ASD, TR and PH had completely disappeared 2 months postoperatively; however, moderate MR persisted. The dog is still alive 5 years postoperatively without clinical signs.

Triple-phase helical computed tomography in dogs with solid splenic masses.

We investigated the utility of triple-phase helical computed tomography (CT) in differentiating between benign and malignant splenic masses in dogs. Forty-two dogs with primary splenic masses underwent triple-phase helical CT scanning (before administration of contrast, and in the arterial phase, portal venous phase, and delayed phase) prior to splenectomy. Tissue specimens were sent for pathological diagnosis; these included hematomas (n=14), nodular hyperplasias (n=12), hemangiosarcomas (n=11), and undifferentiated sarcomas (n=5). The CT findings were compared with the histological findings. Nodular hyperplasia significantly displayed a homogeneous normal enhancement pattern in all phases. Hemangiosarcoma displayed 2 significant contrast-enhancement patterns, including a homogeneous pattern of poor enhancement in all phases, and a heterogeneous remarkable enhancement pattern in the arterial and portal venous phases. Hematoma and undifferentiated sarcoma displayed a heterogeneous normal enhancement pattern in all phases. The contrast-enhanced volumetric ratios of hematoma tended to be greater than those of undifferentiated sarcoma. Our study demonstrated that the characteristic findings on triple-phase helical CT could be useful for the preoperative differentiation of hematoma, nodular hyperplasia, hemangiosarcoma, and undifferentiated sarcoma in dogs. Triple-phase helical CT may be a useful diagnostic tool in dogs with splenic masses.

Epidemiologic study of dogs with the displacement or deformity of the medial and lateral fabellae in Japan.

The prevalences of displacement and deformity of the medial and lateral fabellae in dogs were investigated. This was a retrospective epidemiologic study. Radiographs of canine stifle joints (1022 limbs, 534 dogs) were obtained. The images were taken at the Nihon University Animal Medical Center and three private animal hospitals from January 2003 to July 2012. The position and morphology of the medial or lateral fabella were evaluated on the radiographs. The prevalence of displacement of the medial and lateral fabellae was 1.7% and 0.3%, respectively. The prevalence of deformity of the medial and lateral fabellae was 6.9% and 4.6%, respectively. Aplasia or hypoplasia of the fabella was detected more frequently in the medial fabella. On the other hand, a bipartite or multipartite fabella was observed more frequently in the lateral fabella. Nearly all cases of displacement or deformity of the fabella occurred in dogs weighing less than 10 kg. Abnormalities of the fabella were observed in the medial and lateral fabella. We found that abnormal fabellae were closely associated with medial patellar luxation and to a lesser extent with cranial cruciate ligament rupture. No clinical signs were associated with an abnormality of the fabella, with the exception of two dogs with traumatic avulsion of the lateral head of the gastrocnemius muscle.

Preoperative Differential Diagnosis of Canine Adrenal Tumors Using Triple-Phase Helical Computed Tomography.

OBJECTIVE: To characterize the computed tomography (CT) findings for canine adrenal tumors, including cortical adenoma, cortical adenocarcinoma, and pheochromocytoma, and to evaluate the feasibility and usefulness of preoperative triple-phase helical CT for differentiation of tumor types and surgical planning. STUDY DESIGN: Retrospective study. ANIMALS: Dogs with adrenal tumors (n=36). METHODS: All dogs underwent triple-phase helical CT, followed by adrenalectomy and histopathological diagnosis of the resected mass. Precontrast images, arterial, venous, and delayed phase images were obtained. In all cases, morphological characteristics and CT values and calculations, including the percentage enhancement washout ratio, relative percentage washout, enhancement washin, and enhancement washout, were analyzed and compared among the tumor types. RESULTS: Of the 36 dogs with adrenal masses, cortical adenocarcinoma was most commonly diagnosed (16 dogs), followed by pheochromocytoma (13 dogs), and cortical adenoma (7 dogs). The precontrast minimum CT value and enhancement washout between venous and delayed phases in the cortical adenoma were significantly higher than those in the cortical adenocarcinoma. The maximum CT values of the precontrast image and arterial and venous phases, the enhancement washin and washouts, percentage enhancement washout ratio, and relative percentage washout in the pheochromocytomas were significantly higher than those in cortical adenocarcinoma. CONCLUSION: The differential diagnosis of canine adrenal tumors was feasible based on triple-phase CT findings, including morphological features, CT values, and intratumoral contrast attenuation. Preoperative diagnosis using triple-phase helical CT may be useful for surgical planning in dogs with adrenal tumors.

Evaluation of bone deformities of the femur, tibia, and patella in Toy Poodles with medial patellar luxation using computed tomography.

OBJECTIVES: To evaluate morphological parameters of the femur, tibia, and patella in Toy Poodles with medial patellar luxation (MPL) using three-dimensional (3D) computed tomography (CT) and to compare these parameters between radiography and CT. METHODS: Thirty-five hindlimbs of Toy Poodles were divided into normal and grade 2 and 4 MPL groups. The anatomical and mechanical lateral proximal femoral angle, anatomical and mechanical lateral distal femoral angle (aLDFA, mLDFA), femoral varus angle (FVA), inclination of the femoral head angle, procurvation angle, anteversion angle (AA), frontal angle of the femoral neck, mechanical medial proximal or distal tibial angle, mechanical cranial proximal or distal tibial angle, tibial plateau angle, tibial torsion angle (TTA), Z angle, relative tibial tuberosity width, ratio of the medial distance of tibial tuberosity to the proximal tibial width (MDTT/PTW), patella size, and the patellar ligament length: patellar length (L:P) ratio were evaluated on radiography and 3D CT. RESULTS: The aLDFA, mLDFA, FVA, and TTA were significantly larger and the AA, MDTT/PTW, and patella were significantly smaller in the grade 4 MPL group. There were significant differences in many parameters between imaging tools, and CT was considered less susceptible to potential artefacts and rotational deformities. CLINICAL SIGNIFICANCE: Toy Poodles with grade 4 MPL had significant femoral varus deformity, medial displacement of the tibial tuberosity, internal torsion of the proximal tibia, and hypoplasia of the patella.

Differentiation of canine bone marrow stromal cells into voltage- and glutamate-responsive neuron-like cells by basic fibroblast growth factor.

We investigated the in vitro differentiation of canine bone marrow stromal cells (BMSCs) into voltage- and glutamate-responsive neuron-like cells. BMSCs were obtained from the bone marrow of healthy beagle dogs. Canine BMSCs were incubated with the basal medium for neurons containing recombinant human basic fibroblast growth factor (bFGF; 100 ng/ml). The viability of the bFGF-treated cells was assessed by a trypan blue exclusion assay, and the morphology was monitored. Real-time RT-PCR was performed to evaluate mRNA expression of neuronal, neural stem cell and glial markers. Western blotting and immunocytochemical analysis for the neuronal markers were performed to evaluate the protein expression and localization. The Ca(2+) mobilization of the cells was evaluated using the Ca(2+) indicator Fluo3 to monitor Ca(2+) influx. To investigate the mechanism of bFGF-induced neuronal differentiation, the fibroblast growth factor receptor inhibitor, the phosphoinositide 3-kinase inhibitor or the Akt inhibitor was tested. The bFGF treatment resulted in the maintenance of the viability of canine BMSCs for 10 days, in the expression of neuronal marker mRNAs and proteins and in the manifestation of neuron-like morphology. Furthermore, in the bFGF-treated BMSCs, a high concentration of KCl and L-glutamate induced an increase in intracellular Ca(2+) levels. Each inhibitor significantly attenuated the bFGF-induced increase in neuronal marker mRNA expression. These results suggest that bFGF contributes to the differentiation of canine BMSCs into voltage- and glutamate-responsive neuron-like cells and may lead to the development of new cell-based treatments for neuronal diseases.

Triple-phase helical computed tomography in dogs with hepatic masses.

The purpose of this study was to determine the utility of triple-phase helical computed tomography (CT) for differentiating canine hepatic masses. Seventy dogs with hepatic masses underwent triple-phase CT followed by surgical removal of the hepatic masses. Triple-phase helical CT scans for each dog included precontrast, arterial phase, portal venous phase, and delayed phase studies. The removed hepatic masses were histopathologically classified as hepatocellular carcinoma (n = 47), nodular hyperplasia (n = 14), and hepatic metastatic tumors (n = 9) in dogs. Of the 47 hepatocellular carcinomas, the most common CT findings included a heterogeneous pattern with hyper-, iso-, and hypoenhancement in both the arterial and portal venous phases (40/47, 85.1%). Of the 14 nodular hyperplasias, the most common CT findings were a homogeneous pattern with hyper- and isoenhancement in both the portal venous and delayed phases (13/14, 92.9%). Of nine hepatic metastatic tumors, the most common CT findings included a homogeneous hypoenhancement pattern in both the arterial and portal venous phases (8/9, 88.9%). In addition, 5 (55.6%) showed homogeneous hypoenhancement patterns in the delayed phase. Findings from our study indicated that triple-phase CT is a useful tool for preoperative differentiation of hepatocellular carcinoma, nodular hyperplasia, and hepatic metastatic tumors in dogs.

Effects of cryopreservation on the cell viability, proliferative capacity and neuronal differentiation potential of canine bone marrow stromal cells.

We investigated the cell viability, proliferative capacity and neuronal differentiation potential of canine bone marrow stromal cells (BMSCs) after cryopreservation. BMSCs were cryopreserved using cryoprotectant solutions with 10% DMSO and 10% FBS (DF group) or without DMSO and FBS (DF-free group); fresh BMSCs were used as a control. The cell viability and proliferative capacity of BMSCs were similar in the DF-free and control groups, while those in the DF group were lower. In all groups, BMSCs differentiated into neuron-like cells that stained positive against neuron markers, and the mRNA expression levels of neuron markers increased after neuronal induction. In conclusion, cryopreservation with DF-free cryoprotectant solution did not diminish the cell viability, proliferative capacity or neuronal differentiation potential of canine BMSCs.

Gene expression of growth factors and growth factor receptors for potential targeted therapy of canine hepatocellular carcinoma.

The purpose of this study was to evaluate the gene expression of growth factors and growth factor receptors of primary hepatic masses, including hepatocellular carcinoma (HCC) and nodular hyperplasia (NH), in dogs. Quantitative real-time reverse transcriptase-polymerase chain reaction was performed to measure the expression of 18 genes in 18 HCCs, 10 NHs, 11 surrounding non-cancerous liver tissues and 4 healthy control liver tissues. Platelet-derived growth factor-B (PDGF-B), transforming growth factor-α, epidermal growth factor receptor, epidermal growth factor and hepatocyte growth factor were found to be differentially expressed in HCC compared with NH and the surrounding non-cancerous and healthy control liver tissues. PDGF-B is suggested to have the potential to become a valuable ancillary target for the treatment of canine HCC.

Evaluation of mRNA expression levels and electrophysiological function of neuron-like cells derived from canine bone marrow stromal cells.

OBJECTIVE: To investigate the in vitro differentiation of canine bone marrow stromal cells (BMSCs) into functional, mature neurons. SAMPLE: Bone marrow from 6 adult dogs. PROCEDURES: BMSCs were isolated from bone marrow and chemically induced to develop into neurons. The morphology of the BMSCs during neuronal induction was monitored, and immunocytochemical analyses for neuron markers were performed after the induction. Real-time PCR methods were used to evaluate the mRNA expression levels of markers for neural stem or progenitor cells, neurons, and ion channels, and western blotting was used to assess the expression of neuronal proteins before and after neuronal induction. The electrophysiological properties of the neuron-like cells induced from canine BMSCs were evaluated with fluorescent dye to monitor Ca(2)+ influx. RESULTS: Canine BMSCs developed a neuron-like morphology after neuronal induction. Immunocytochemical analysis revealed that these neuron-like cells were positive for neuron markers. After induction, the cells' mRNA expression levels of almost all neuron and ion channel markers increased, and the protein expression levels of nestin and neurofilament-L increased significantly. However, the neuron-like cells derived from canine BMSCs did not have the Ca(2)+ influx characteristic of spiking neurons. CONCLUSIONS AND CLINICAL RELEVANCE: Although canine BMSCs had neuron-like morphological and biochemical properties after induction, they did not develop the electrophysiological characteristics of neurons. Thus, these results have suggested that canine BMSCs could have the capacity to differentiate into a neuronal lineage, but the differentiation protocol used may have been insufficient to induce development into functional neurons.

Proliferation capacity, neuronal differentiation potency and microstructures after the differentiation of canine bone marrow stromal cells into neurons.

We examined the proliferation capacity and neuronal differentiation potency of canine bone marrow stromal cells (BMSCs). In addition, the microstructures of neuron-like cells after neuronal differentiation were observed under a scanning electron microscope. Canine BMSCs grew to confluency at 10.0 ± 2.5 days, and 3.8 ± 2.1 × 10(6) BMSCs were collected in one passage. Approximately 65% of canine BMSCs changed to neuron-like morphology after neuronal differentiation, and nearly all neuron-like cells stained positive against neuron-specific enolase. In addition, microstructures such as the cellular organelles, filaments and growth cones of these cells bore a close resemblance to those of the original mature neurons. These results suggested that canine BMSCs might be capable of differentiating into neurons.

Influence of an autologous serum-supplemented medium on the proliferation and differentiation into neurons of canine bone marrow stromal cells.

We investigated the influence of autologous serum (AS)-supplemented medium on the proliferation and differentiation into neurons of canine bone marrow stromal cells (BMSCs). Canine BMSCs were cultured using α-MEM only, α-MEM with 10% fetal bovine serum (FBS), and 5, 10 and 20% AS-supplemented α-MEM. Growth of canine BMSCs was observed in all AS groups. The proliferation capacity of canine BMSCs in the AS groups was similar to that in the FBS group. No significant differences between the FBS and AS groups were observed in the percentage of the cells that changed to the neuron-like morphology and neuron-specific enolase-positive ratio after neuronal differentiation. Canine BMSCs cultured using AS-supplemented medium were able to proliferate and showed neuronal differentiation potency.

Plasma adrenomedullin concentration in dogs with myxomatous mitral valvular disease.

Adrenomedullin (AM), a peptide identified to have vasodilating and natriuretic effects, is involved in the regulation of the cardiovascular system. To evaluate plasma AM concentration in dogs with myxomatous mitral valvular disease (MMVD), and to investigate the associations between the concentrations of plasma AM and natriuretic peptides and the echocardiographic data, we evaluated plasma AM concentrations in 31 healthy control dogs and 57 dogs with MMVD. Plasma AM concentrations in dogs with MMVD were higher than that in the control subjects. The plasma AM concentration increased in conjunction with the severity of heart failure according to the International Small Animal Cardiac Health Council (ISACHC). The AM concentrations were 25.1 ± 5.0 fmol/ml (ISACHC class Ia), 29.9 ± 11.0 fmol/ml (ISACHC class Ib), 43.4 ± 19.8 fmol/ml (ISACHC class II) and 73.5 ± 21.7 fmol/ml (ISACHC class III) and 7.5 ± 5.1 fmol/ml (control group), respectively. The receiver operating characteristic curve indicated an area of 0.93 (95% CI, 0.8801-0.9889; <0.0001), a cutoff value of 30.5 fmol/ml, a sensitivity of 87.1%, and a specificity of 82.5% for the determination of congestive heart failure. Plasma AM concentrations correlated with atrial natriuretic peptide concentrations, LA/Ao ratio, and left ventricular diameter. In conclusion, AM may be a potential diagnostic marker for canine MMVD and possibly plays a pathophysiological role in collaboration with the other neurohumoral factors such as natriuretic peptides.

En block resection of a large hepatocellular carcinoma involving the caudal vena cava in a dog.

A 13-year-old neutered female Shih Tzu was referred for investigation of a cranial abdominal mass. Investigations including conventional radiography, abdominal ultrasonography and computed tomography confirmed the mass in the caudate lobe of the liver. As a collateral vein originating from the caudal vena cava (CVC) communicated with the azygos vein, the CVC was ligated and transected cranial to the right renal vein and cranial to the mass under temporary occlusion of the thoracic descending aorta and posthepatic CVC. The mass combined with the CVC was excised. The mass was confirmed as hepatocellular carcinoma (HCC). This report describes the first case with successful en bloc resection of a large HCC involving the CVC in a dog.

Cloning of prepro-adrenomedullin and mRNA expression in cats.

The objective of this paper was to evaluate the sequence of feline prepro-adrenomedullin (AM) and its tissue distribution and to investigate whether expression of feline AM mRNA increases in association with spontaneous cardiomyopathy. The feline prepro-AM cDNA sequence and deduced amino acids were 564 base pairs and 188 residues, respectively. The cDNA sequences of feline prepro-AM including AM and proadrenomedullin N-terminal 20 peptide showed high homology with those of other mammalian species. The mRNA expression of AM was detectable in various normal tissues. The mRNA levels of AM were elevated in hearts with cardiomyopathy compared with normal hearts. This study suggests that AM has an important role as a neurohumoral factor in cats with spontaneous heart diseases.