Comparison of the effect of single-site and multiple-site disk fenestration on the rate of recurrence of thoracolumbar intervertebral disk herniation in dogs.

OBJECTIVE: To prospectively assess whether multiple-site disk fenestration decreases the incidence of recurrent thoracolumbar intervertebral disk herniation (IVDH), compared with single-site disk fenestration, in small-breed dogs treated for IVDH. DESIGN: Randomized controlled clinical trial. ANIMALS: 207 client-owned dogs. PROCEDURES: Dogs undergoing decompressive surgery of the spinal cord because of thoracolumbar IVDH between 2001 and 2004 were randomly assigned to receive single-site disk fenestration at the level of surgical decompression (n = 103) or multiple-site disk fenestration of all disks from T11 through L4 (104). Follow-up consisted of complete reevaluation of patients, telephone surveys, and further surgery if signs indicative of recurrence occurred. RESULTS: 189 dogs were available for long-term follow-up: 95 dogs in the single-site disk fenestration group and 94 in the multiple-site disk fenestration group. Twenty-four dogs developed 28 confirmed episodes of recurrent thoracolumbar IVDH. The rate for first-time recurrence was 12.7% (24/189). First-time recurrence rates for single-and multiple-site disk fenestration groups were 17.89% (17/95) and 7.45% (7/94), respectively. Dogs undergoing single-site disk fenestration were significantly more likely to have recurrent thoracolumbar IVDH than were dogs undergoing multiple-site disk fenestration. Disk mineralization at the time of first surgery was associated with recurrence, and 87.5% (21/24) of recurrences occurred at a disk space adjacent to or 1 disk away from the initial lesion. Regardless of disk fenestration group, 22 of 24 (91.7%) recurrences occurred at a nonfenestrated disk space. CONCLUSIONS AND CLINICAL RELEVANCE: Multiple-site disk fenestration decreased the rate of recurrent IVDH in small-breed dogs, compared with the use of single-site disk fenestration.

Branchial cysts in two Amazon parrots (Amazona species).

A 37-year-old yellow-crowned Amazon parrot (Amazona ochrocephala) and a 20-year-old red-lored Amazon parrot (Amazona autumnalis) each presented with a large mass localized on the lateral neck. With the first bird, there was no evidence of signs of pain or discomfort, and the bird prehended and swallowed food normally. The second bird showed signs of mild upper-gastrointestinal discomfort. Results of an ultrasound examination and aspiration of the mass on each bird revealed a cystic structure. A computed tomography performed on the second bird revealed a large polycystic mass connected to the pharynx by a lateral tract. During surgical resection, both masses were found to originate from the subpharyngeal area. Based on topography and the histopathologic and immunohistochemical results, the masses were determined to be a second branchial cleft cyst for the first case and a second branchial pouch cyst for the second case. In addition, a carcinoma was present in situ within the epithelium of case 1, and the cyst in case 2 was secondarily infected. Branchial cysts are uncommonly diagnosed in veterinary and human medicine. These 2 cases are the first documented in parrots and appear similar to second branchial cysts reported in adult humans.

Anesthetic management of an off-pump open-heart surgery in a dog.

OBSERVATIONS: A 9 year-old, 40 kg, female spayed Bouvier des Flandres was anesthetized for surgical removal of an intra-cardiac mass. Pre-anesthetic work-up included thoracic radiographs, which revealed moderate pleural effusion, and cardiac ultrasound, which identified a mass attached to the wall of the right ventricular outflow tract (RVOT). The mass caused dynamic obstruction of the RVOT during systole. The dog was pre-medicated with intravenous (IV) hydromorphone (0.05 mg kg(-1)). Following pre-oxygenation, anesthesia was induced with ketamine (3.75 mg kg(-1), IV) and diazepam (0.18 mg kg(-1), IV). Anesthesia was maintained with isoflurane in oxygen, an intravenous constant rate infusion (CRI) of fentanyl (10-30 microg kg(-1) hour(-1)) and a CRI of lidocaine (50-200 microg kg(-1) minute(-1)). A right lateral thoracotomy was performed. The heart was stopped transiently with a cold cardioplegic solution for 7.83 minutes to allow the removal of the mass through an open-heart procedure. No cardiopulmonary bypass was used. The heart was successfully restarted after cardiopulmonary resuscitation with internal cardiac massage and internal defibrillation. The dog recovered uneventfully from anesthesia without any apparent neurological sequelae. Post-operative analgesia consisted of intercostal nerve blocks with bupivacaine, CRIs of fentanyl (2-5 microg kg(-1) hour(-1)) and lidocaine (40 microg kg(-1) minute(-1)) and with oral meloxicam (0.1 mg kg(-1)). Five days following surgery, the dog was discharged from the hospital. Histopathology and immunohistochemistry of the mass identified an ectopic thyroid carcinoma. CONCLUSIONS: This case showed the feasibility of whole body hypothermia and using a cold cardioplegic solution to induce cardiac arrest for a short open-heart procedure.

Ectopic thyroid carcinoma causing right ventricular outflow tract obstruction in a dog.

A 9-year-old Bouvier des Flandres was presented with coughing, lethargy, chylous pleural effusion, and a heart murmur. An echocardiogram revealed the presence of an intracardiac mass causing right ventricular outflow tract obstruction. The mass was successfully removed surgically, using total inflow occlusion. Histopathology and immunohistochemistry identified the tumor as an ectopic thyroid carcinoma. The dog was euthanized 11 months after diagnosis at the request of the owner because of nonresolving chylothorax.

Evaluation of risk factors associated with suture-nidus cystoliths in dogs and cats: 176 cases (1999-2006).

OBJECTIVE: To characterize and evaluate risk factors for suture-associated cystoliths in dogs and cats. DESIGN: Retrospective case-control study. Animals-163 dogs and 13 cats with suture-associated cystoliths and 326 control dogs and 26 control cats with non-suture-associated cystoliths. PROCEDURES: Submissions to the Canadian Veterinary Urolith Centre received from 1999 to 2006 were reviewed. Case dogs and cats had cystoliths associated with visible suture or with hollow, cylindrical channels or suture knot impressions consistent with dissolved suture. Control dogs and cats had at least a single recurrent non-suture-associated cystolith submitted closest in time to the sample case. Associations among cystolith composition, recurrence times, sex, age, and breed were evaluated. RESULTS: Cases consisted of 92 dogs and 7 cats with visible suture and 71 dogs and 6 cats with dissolved suture. Suture-associated cystoliths represented 0.6% of canine cystoliths, 9.4% of recurrent canine cystoliths, 0.17% of feline cystoliths, and 4% of recurrent feline cystoliths. Sexually intact and neutered males were at increased odds of suture-associated cystoliths, relative to spayed female dogs. Shih Tzus, Lhasa Apsos, and Pomeranians were significantly predisposed to form suture-associated cystoliths. In dogs, compound suture-associated cystoliths were significantly more likely than other cystolith types (OR, 8.6). Dogs with suture-associated cystoliths had significantly shorter recurrence times than did control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Suture remnants in the bladder have an important role in recurrent cystolithiasis in dogs. Identification of risk factors is important for avoiding recurrence of iatrogenic cystoliths.

Outcome of medical and surgical treatment in dogs with cervical spondylomyelopathy: 104 cases (1988-2004).

OBJECTIVE: To compare outcomes and survival times for dogs with cervical spondylomyelopathy (CSM; wobbler syndrome) treated medically or surgically. DESIGN: Retrospective case series. ANIMALS: 104 dogs. PROCEDURES: Medical records of dogs were included if the diagnosis of CSM had been made on the basis of results of diagnostic imaging and follow-up information (minimum, 6 months) was available. Ordinal logistic regression was used to compare outcomes and the product-limit method was used to compare survival times between dogs treated surgically and dogs treated medically. RESULTS: 37 dogs were treated surgically, and 67 were treated medically. Owners reported that 30 (81%) dogs treated surgically were improved, 1 (3%) was unchanged, and 6 (16%) were worse and that 36 (54%) dogs treated medically were improved, 18 (27%) were unchanged, and 13 (19%) were worse. Outcome was not significantly different between groups. Information on survival time was available for 33 dogs treated surgically and 43 dogs treated medically. Forty of the 76 (53%) dogs were euthanized because of CSM. Median and mean survival times were 36 and 48 months, respectively, for dogs treated medically and 36 and 46.5 months, respectively, for dogs treated surgically. Survival times did not differ significantly between groups. CONCLUSIONS AND CLINICAL RELEVANCE: In the present study, neither outcome nor survival time was significantly different between dogs with CSM treated medically and dogs treated surgically, suggesting that medical treatment is a viable and valuable option for management of dogs with CSM.

Use of the ventrodorsal myelographic view to predict lateralization of extruded disk material in small-breed dogs with thoracolumbar intervertebral disk extrusion: 104 cases (2004-2005).

OBJECTIVE: To determine whether the ventrodorsal myelographic view can be used to accurately predict the circumferential location of extruded disk material in dogs with thoracolumbar intervertebral disk extrusion (IVDE) and to describe paradoxical contrast obstruction (PCO). DESIGN: Retrospective case series. ANIMALS: 104 dogs with Hansen type I IVDE. Procedures-Ventrodorsal myelographic views were reviewed, and contrast patterns were categorized according to 8 predetermined patterns. Agreement among observers was compared, and the predicted location of extruded disk material was compared with surgical findings. RESULTS: Agreement regarding myelographic pattern and location of extruded disk material was moderate (kappa = 0.74 and 0.80, respectively) among the 4 observers. Ninety-three (89%) dogs had myelographic evidence of lateralized extrusion, and in 83 of the 93 (89%), predicted location of extruded disk material matched the surgically confirmed location. In 33 of the 40 (83%) dogs with bilateral contrast column gaps of unequal length, disk material was found to be located on the side with the shorter, rather than the longer, contrast gap, a phenomenon described as PCO. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that the ventrodorsal myelographic view could be used to predict the circumferential location of extruded disk material in dogs with thoracolumbar IVDE more often than previously reported. The PCO phenomenon may be useful in determining the side of lateralization when contrast material does not outline the extruded disk material.

Cianose e metahemoglobinemia associada à deficiência de NADH-metahemoglobina redutase em um cão sob anestesia / Cyanosis and methahemoglobinaemia associated with NADH-methahemoglobin reductase deficiency in a dog under anesthesia

Este estudo relata a ocorrência de cianose em um cão sob anestesia geral. O paciente não apresentava sinal de doençacardíaca ou respiratória, não havia possibilidade de ingestão acidental de agentes oxidantes, resultando então na suspeita demetahemoglobinemia associada à deficiência de NADH-metahemoglobina redutase. Sendo esta confirmada após testesugestivo e confirmação laboratorial por teste específico

This study reports the occurrence of cyanosis in a dog under general anesthesia. The patient didn’t present any sign of heart orrespiratory disease, the accidental ingestion of oxidizers agents wasn’t possible. Therefore resulting the suspicion ofmetahemoglobinemia associated to the deficiency of NADH-metahemoglobina redutase. This was confirmed after suggestivetest and laboratorial specific test

Morphologic and morphometric magnetic resonance imaging features of Doberman Pinschers with and without clinical signs of cervical spondylomyelopathy.

OBJECTIVE: To compare morphologic and morphometric features of the cervical vertebral column and spinal cord of Doberman Pinschers with and without clinical signs of cervical spondylomyelopathy (CSM; wobbler syndrome) detected via magnetic resonance imaging (MRI). ANIMALS: 16 clinically normal and 16 CSM-affected Doberman Pinschers. PROCEDURES: For each dog, MRI of the cervical vertebral column (in neutral and traction positions) was performed. Morphologically, MRI abnormalities were classified according to a spinal cord compression scale. Foraminal stenosis and intervertebral disk degeneration and protrusion were also recorded. Morphometric measurements of the vertebral canal and spinal cord were obtained in sagittal and transverse MRI planes. RESULTS: 4 of 16 clinically normal and 15 of 16 CSM-affected dogs had spinal cord compression. Twelve clinically normal and all CSM-affected dogs had disk degeneration. Foraminal stenosis was detected in 11 clinically normal and 14 CSM-affected dogs. Vertebral canal and spinal cord areas were consistently smaller in CSM-affected dogs, compared with clinically normal dogs. In neutral and traction positions, the intervertebral disks of CSM-affected dogs were wider than those of clinically normal dogs but the amount of disk distraction was similar between groups. CONCLUSIONS AND CLINICAL RELEVANCE: The incidence of intervertebral disk degeneration and foraminal stenosis in clinically normal Doberman Pinschers was high; cervical spinal cord compression may be present without concurrent clinical signs. A combination of static factors (ie, a relatively stenotic vertebral canal and wider intervertebral disks) distinguished CSM-affected dogs from clinically normal dogs and appears to be a key feature in the pathogenesis of CSM.

A prospective comparison of postoperative morbidity associated with the use of scalpel blades and lasers for onychectomy in cats.

This study compared patient discomfort for 10 d following feline onychectomies performed using a CO2 surgical laser versus a scalpel blade. Both techniques appeared to result in discomfort of a similar duration, although the laser caused significantly less lameness than blade excision during the first 7 d.

Comparison of mesenteric lymphadenography performed via surgical and laparoscopic approaches in dogs.

OBJECTIVE: To determine whether injection of a mesenteric lymph node with iodinated aqueous contrast medium results in radiographic delineation of the thoracic duct and its branches, ascertain the ideal interval between injection and radiographic imaging, and evaluate mesenteric lymphadenography performed via laparoscopic and surgical approaches in dogs. ANIMALS: 10 adult dogs. PROCEDURE: In each dog, a right paracostal laparotomy or a right laparoscopic approach was performed to identify a mesenteric lymph node for injection of an iodinated aqueous contrast agent (0.22 mL/kg [81.4 mg of iodine/kg]). Lateral radiographic views were obtained at 60, 120, 180, 240, and 300 seconds after injection. RESULTS: A mesenteric lymph node was identified and injected with contrast medium in each dog. Via paracostal laparotomy, lymph node injection resulted in successful lymphangiographic evaluation in 4 of 5 dogs, whereas via the laparoscopic approach, lymph node injection resulted in successful lymphangio-graphic evaluation in 2 of 5 dogs. In successful radiographic evaluations, injected lymph nodes, mesenteric lymphatics, and the thoracic duct and its branches were delineated. Radiographs obtained at 60 and 120 seconds after injection of contrast medium provided the most detail. CONCLUSIONS AND CLINICAL RELEVANCE: Injection of a mesenteric lymph node directly with contrast medium appears to be a feasible technique for delineation of the thoracic duct and its branches in dogs and might be useful in small animals in which mesenteric lymphatic catheterization can be difficult and lymphangiography is more likely to fail. Refinement of the laparoscopic technique may provide a minimally invasive approach to lymphadenography.

Bile peritonitis associated with gastric dilation-volvulus in a dog.

This report describes a case of septic peritonitis and gall bladder rupture in German shepherd dog that developed 7 d after surgical treatment for gastric dilation-volvulus. Histological examination confirmed gall bladder necrosis, secondary to an acute ischemic event. Postoperative acute necrotizing cholecystitis has not been a previously reported complication in dogs.

Metastatic anal sac adenocarcinoma in a dog presenting for acute paralysis.

A 4-year old, female spayed terrier was referred for hind end paresis that rapidly progressed to paralysis. Spinal radiographs revealed vertebral collapse and bony lysis. Myelography confirmed spinal cord compression and surgical exploration found an extradural soft tissue mass. Metastatic anal sac adenocarcinoma was diagnosed at postmortem examination.

Correlation between severity of clinical signs and motor evoked potentials after transcranial magnetic stimulation in large-breed dogs with cervical spinal cord disease.

OBJECTIVE: To evaluate use of transcranial magnetic motor evoked potentials for assessment of the functional integrity of the cervical spinal cord in large-breed dogs with cervical spinal cord disease. DESIGN: Randomized, controlled, masked study. ANIMALS: 10 healthy large-breed control dogs and 25 large-breed dogs with cervical spinal cord diseases. PROCEDURE: Affected dogs were allocated to 3 groups on the basis of neurologic status: signs of neck pain alone, ambulatory with ataxia in all limbs, or nonambulatory. Transcranial magnetic stimulation was performed on each dog with the same standard technique. Motor evoked potentials (MEP) were recorded from electrodes inserted in the tibialis cranialis muscle. Following the procedure, each dog was anesthetized and cervical radiography, CSF analysis, and cervical myelography were performed. The MEP latencies and amplitudes were correlated with neurologic status of the dogs after correction for neuronal path length. RESULTS: Mean MEP latencies and amplitudes were significantly different between control dogs and dogs in each of the 3 neurologic categories, but were not significantly different among dogs in the 3 neurologic categories. A linear association was evident between MEP latencies and amplitudes and severity of neurologic deficits; the more severe the neurologic deficits, the more prolonged the latencies and the more decreased the amplitudes. CONCLUSIONS AND CLINICAL RELEVANCE: Transcranial magnetic MEP are useful to assess severity of cervical spinal cord disease in large-breed dogs. Impairment of the functional integrity of the cervical spinal cord was found even in dogs with neck pain alone.