Ex vivo comparison of pin placement with patient-specific drill guides or freehand technique in canine cadaveric spines.

OBJECTIVE: To compare vertebral implant placement in the canine thoracolumbar spine between 3D-printed patient-specific drill guides (3DPG) and the conventional freehand technique (FH). STUDY DESIGN: Ex vivo study. ANIMALS: Cadaveric canine spines (n = 24). METHODS: Implant trajectories were established for the left and right sides of the T10 through L6 vertebrae based on computed tomography (CT) imaging. Customized drill guides were created for each vertebra of interest. Each cadaver was randomly assigned to one of six veterinarians with varying levels of experience placing vertebral implants. Vertebrae were randomly assigned a surgical order and technique (3DPG or FH) for both sides. Postoperative CT images were acquired. A single, blinded observer assessed pin placement using a modified Zdichavsky classification. RESULTS: A total of 480 implants were placed in 240 vertebrae. Three sites were excluded from the analysis; therefore, a total of 238 implants were evaluated using the FH technique and 239 implants using 3DPG. When evaluating implant placement, 152/239 (63.6%) of 3DPG implants were considered to have an acceptable placement in comparison with 115/248 (48.32%) with FH. Overall, pin placement using 3DPG was more likely to provide acceptable pin placement (p < .001) in comparison with the FH technique for surgeons at all levels of experience. CONCLUSION: The use of 3DPG was shown to be better than the conventional freehand technique regarding acceptable placement of implants in the thoracolumbar spine of canine cadavers. CLINICAL SIGNIFICANCE: Utilizing 3DPG can be considered better than the traditional FH technique when placing implants in the canine thoracolumbar spine.

Indications, complications, and mortality rate following craniotomy or craniectomy in dogs and cats: 165 cases (1995-2016).

OBJECTIVE: To determine the most common indications for cranial surgery and identify risk factors associated with the occurrence of complications and death in the perioperative period following cranial surgery. ANIMALS: 150 dogs and 15 cats. PROCEDURES: For this multi-institutional retrospective case series, medical records of dogs and cats that underwent cranial surgery at any of the 4 participating institutions between 1995 and 2016 were reviewed. Variables were evaluated included species, sex, age, neurolocalization, history of preoperative seizures, surgical approach, histological results, perioperative complications, and outcome. Logistic regression analysis was performed to assess for risk factors for complications. RESULTS: The most common neurolocalization was the forebrain (110/165 [66.7%]), with 94 (57.0%) animals having had seizures preoperatively. The rostrotentorial (116/165 [70.3%]) and caudotentorial (32/165 [19.4%]) surgical approaches were most commonly reported. The most common indication was the treatment of meningioma (75/142 [52.8%]). Complications arose in 58 of the 165 (35.2%) cases within 24 hours and in 86 (52.1%) cases 1 to 10 days postoperatively. Perioperative complications included hypotension (38/165 [23.0%]) and anemia (27/165 [16.4%]). During the postoperative period, the most common complications were neurologic deficits, seizures, postoperative anemia, and aspiration pneumonia. The mortality rate with death or euthanasia perioperatively or ≤ 10 days postoperatively was 14.5% (24/165). Long-term complications occurred in 65 of the 165 (39.4%) animals, with seizures and neurologic deficits being the most common. CLINICAL RELEVANCE: Cranial surgery was performed most commonly for the removal of neoplastic lesions in dogs and cats, and most complications were not life-threatening.

Assessment of the cutaneous trunci reflex in neurologically healthy cats.

OBJECTIVES: The aim of this study was to perform the cutaneous trunci reflex (CTR) in neurologically normal cats using two different instruments and determine how body condition score (BCS), body circumference, age, sex and instrument type may affect this reflex. METHODS: Sixty-five cats without evidence of neurologic disease were prospectively enrolled. Cats were randomly assigned to have the reflex tested first using a pair of hemostatic forceps or the integrated Babinski tip of an MDF Babinski Buck Reflex Hammer. After 30 mins, the reflex was retested using the other instrument. Data collected included the reflex presence, reflex caudal border, reflex intensity (weak, moderate, strong) and reflex symmetry (unilateral or bilateral). The influence of BCS, body circumference, age and sex on these variables was statistically evaluated along with effect of the instrument used. RESULTS: The CTR was elicited bilaterally in 52 (80%) cats and unilaterally in 64 (98%) cats. In two cats, the CTR was only able to be elicited using the Buck Reflex Hammer, while in four cats, the CTR was only able to be elicited using hemostatic forceps. Body circumference, BCS, age and sex had no effect on the presence, caudal border, intensity or symmetry of the CTR, regardless of the instrument used. No difference in the bilateral presence of the CTR was noted based on the instrument used first (P = 0.53). When assessing the influence of the instrument on reflex presence, caudal border, intensity and symmetry, the hemostatic forceps elicited the reflex further caudally (P = 0.02) and usually bilaterally (P = 0.02). CONCLUSIONS AND RELEVANCE: The CTR could be elicited in the majority of cats with both instruments. However, hemostatic forceps elicited a reflex more caudally and bilaterally symmetrical than the Buck Reflex Hammer.

Assessment of the cutaneous trunci muscle reflex in neurologically abnormal cats.

OBJECTIVES: The aim of this study was to evaluate the presence of the cutaneous trunci reflex (CTR) in a population of neurologically abnormal cats in regard to age, body condition score (BCS), sex, breed, evidence of traumatic injury, pain, known metabolic disease, mentation, neurolocalization and diagnostic classification. METHODS: A retrospective medical record review was performed to identify cats with a history of neurologic disease undergoing a complete neurologic assessment between 24 September 2012 and 20 March 2019. CTR outcome (present, absent), signalment, evidence of traumatic injury, pain, known metabolic disease, mentation, neurolocalization and diagnostic classification were recorded. RESULTS: A total of 182 cats were identified. The CTR was present in 118 cats (64.8%) and absent in 64 cats (35.2%). Statistical analysis revealed no association between CTR outcome and age, BCS, sex, breed, evidence of traumatic injury, non-spinal pain, known metabolic disease, mentation, neurolocalization or diagnostic classification. A significant association was found between spinal pain and CTR outcome (P = 0.037). CONCLUSIONS AND RELEVANCE: These findings suggest that elicitation of the CTR in the cat can be unreliable. Further prospective controlled studies are warranted to determine whether continued inclusion of the CTR in feline neurologic examinations is justified. Consideration of the reliability of the CTR is indicated, particularly in the context of fractious or anxious patients for which only a limited window for examination may be present.

Noise-Induced Hearing Loss in 3 Working Dogs.

Three working dogs were diagnosed with noise-induced hearing loss following exposure to loud noise. Physical and neurologic examinations in each case revealed no significant findings. Brainstem auditory evoked response (BAER) demonstrated bilateral sensorineural deafness. One dog did not regain hearing but continued working with adjusted protocols utilizing hand signals. One dog was lost to follow-up. The last dog was treated with oral Vitamin B complex (daily), Vitamin E (400 IU daily), and N-acetyl-cystine (600 mg daily) and regained hearing 2 months later, based on repeat BAER testing.

Glioma Mimics: Magnetic Resonance Imaging Characteristics of Granulomas in Dogs.

Granulomas can "mimic" gliomas on magnetic resonance imaging (MRI) in human patients. The goal of this retrospective study was to report canine brain granulomas that were consistent with glioma based upon MRI, report their histologic diagnosis, and identify MRI criteria that might be useful to distinguish granuloma from glioma. Ten granulomas, initially suspected to be glioma based on MRI, were ultimately diagnosed as granulomatous meningoencephalomyelitis (n = 5), infectious granulomas (n = 3) or other meningoencephalitis (n = 2). Age was 1.6-15.0 years and two dogs were brachycephalic breeds. MRI characteristics overlapping with glioma included intra-axial, heterogeneous, T2-weighted hyperintense, T1-weighted hypointense to isointense mass lesions with contrast-enhancement. Signals on fluid attenuation inversion recovery, gradient echo and diffusion weighted imaging also matched glioma. Peri-lesional edema and mass effect were toward the high end of findings reported for glioma. MRI characteristics that would be considered unusual for glioma included dural contact (n = 4), T2-hypointensity (n = 2), concomitant meningeal-enhancement (n = 9), and minor changes in the contralateral brain (n = 2). Cerebrospinal fluid analysis revealed albuminocytological dissociation or mild pleocytosis. These cases show that granulomas can "mimic" glioma on canine brain MRI. In individual cases, certain MRI findings may help increase the index of suspicion for granuloma. Lack of pronounced cerebrospinal fluid pleocytosis does not exclude granuloma. Signalment is very useful in the suspicion of glioma, and many of these dogs with granuloma were of ages and breeds in which glioma is less commonly seen.

The utility of intraoperative impression smear cytology of intracranial granular cell tumors: Three cases.

Two adult male dogs (a 7-year-old shorthaired Chihuahua and 14-year-old Shih Tzu) and one adult female dog (a 9-year-old Maltese) presented for evaluation of new-onset seizure activity. Magnetic resonance imaging of the brain demonstrated a large, poorly marginated T2-weighted hyperintense, and strong contrast enhancing extra-axial mass in each case. A surgical biopsy for histopathologic evaluation was elected in all cases, and intraoperative impression smears were successfully obtained. Intraoperative cytology identified a homogenous population of round to polygonal cells with central to eccentric nuclei, coarse chromatin, and variably amphophilic to eosinophilic granular cytoplasm. Cytologic findings led to a suspected diagnosis of granular cell tumor (GCT) in all cases. Histopathologic review identified a densely cellular, unencapsulated neoplastic mass comprised of sheets of large round to polygonal cells with abundant eosinophilic cytoplasm containing numerous eosinophilic intracytoplasmic granules, confirming the diagnosis of GCT in all cases. The cases reported here are unique in that they reveal an accurate intraoperative cytologic diagnosis of a rare canine central nervous system neoplasm. Intraoperative cytology of the intracranial masses could provide clinicians with important and quick diagnostic and prognostic information; therefore, expediting decisions made intraoperatively. Further research is warranted to determine the diagnostic accuracy of intraoperative cytology for neoplasia in veterinary patients.

Effect of implementation of a surgical safety checklist on perioperative and postoperative complications at an academic institution in North America.

OBJECTIVE: To evaluate the efficacy of a surgical safety checklist (SSC) in reducing perioperative and postoperative complications. STUDY DESIGN: Before-and-after intervention study. ANIMALS: Client-owned dogs (n = 633) and cats (n = 44). METHODS: Consecutive surgeries were enrolled in the study. The "before" phase consisted of 267 surgeries performed without an SSC (SSC- ) followed by 75 SSC- surgeries in which a trained observer was in the operating room to detect possible complications. An SSC was then implemented in the operating rooms during 1 week. The "after" phase consisted of 58 surgeries in which a safety checklist (SSC+ ) and an observer were used and 277 SSC+ surgeries without an observer. Complications were prospectively recorded when witnessed by the observer, and all other perioperative complications were retrospectively recorded from veterinary records and client telephone communication. RESULTS: There were more perioperative and postoperative complications when surgeries were performed without an SSC (140/342 [40.9%; 95% CI, 35.7%-46.4%]) than there were when surgeries were performed with an SSC (98/335 [29.3%; 95% CI, 24.4%-34.4%]; P = .002). Surgical checklist use, presence of an observer, American Society of Anesthesiologists score, and anesthesia time were all independently associated with the odds of complications. CONCLUSION: Implementation of an SSC in an academic teaching hospital decreased the odds of perioperative and postoperative surgical complications. CLINICAL SIGNIFICANCE: This study supports the use of an SSC to prevent surgical complications in veterinary teaching hospitals.

Effects of interstitial cystitis on the acoustic startle reflex in cats.

OBJECTIVE: To compare acoustic startle reflexes (ASRs) of healthy cats and cats with interstitial cystitis (IC). ANIMALS: 28 healthy cats (11 males and 17 females) and 20 cats with IC (13 males and 7 females). PROCEDURES: To evaluate the effect of neutering on ASRs, ASRs in neutered and unneutered healthy cats were measured. To evaluate the effect of housing facility acclimation on ASRs in cats with IC, ASRs were measured in cats with IC within 1 month after arrival at the housing facility and again 2 to 3 months after arrival. To evaluate the effect of the environment on ASRs, ASRs were evaluated in all cats with and without IC after acclimation but before and then after environmental enrichment. RESULTS: Neutering led to a significant decrease in overall ASR in the healthy cats. Habituation to the housing facility resulted in a significant decrease in overall ASR of female but not male cats with IC. Environmental enrichment led to a significant decrease in ASR in cats with IC but not in healthy cats. CONCLUSIONS AND CLINICAL RELEVANCE: The magnitude of the ASR appeared to be sensitive to environmental conditions and affected by sex, both in healthy cats and cats with IC. It was also higher in cats with IC versus healthy cats, except when cats were housed in a highly enriched environment. IMPACT FOR HUMAN MEDICINE: Treatment approaches that include reduction of a patient's perception of environmental unpredictability may benefit humans with IC.