Bilateral ceratohyoidectomy for the resolution of clinical signs associated with temporohyoid osteoarthropathy

Temporohyoid osteoarthropathy (THO) is a progressive bilateral disease of unknown aetiology that most commonly affects adult horses. Irrespective of aetiology, THO frequently results in pain or fracture of the petrous temporal bone during normal movement of the tongue and larynx. In an effort to decrease pain and reduce the likelihood of petrous temporal bone fracture, partial stylohyoidectomy and ceratohyoidectomy have been developed. Serious complications have been reported following stylohyoidectomy and therefore the current recommendation is to perform unilateral ceratohyoidectomy. Benefits of ceratohyoidectomy include a lower risk of vascular and nerve damage and a reduced risk of clinical signs recurrence when compared with stylohyoidectomy. This report describes a case of THO in which clinical signs recurred approximately 2 years after unilateral ceratohyoidectomy was performed. Due to this complication, resection of the contralateral ceratohyoid bone was performed, which resulted in complete resolution of clinical signs. Although the clinical signs are frequently unilateral, the disease is most commonly a progressive bilateral condition and some horses may not have complete resolution of clinical signs when unilateral ceratohyoidectomy is performed. Therefore, if clinical signs persist after unilateral ceratohyoidectomy, a therapeutic consideration should include bilateral ceratohyoidectomy. This report suggests a favourable short‐term prognosis for a horse treated with bilateral ceratohyoidectomy.     

Use of BAER to identify loss of auditory function in older horses

Objective To use the brainstem auditory evoked response (BAER) to test the hypothesis that auditory function could be worse in older horses than in younger horses. Procedure BAER waveforms in response to click stimuli were measured in five younger horses (5–8 years) and four older horses (17–22 years). Results Compared with the younger horses, the older horses showed significantly (P < 0.02) worse BAER thresholds and significantly (P < 0.02) worse BAER wave V amplitudes to the 90 decibels above normal hearing level stimulus. These results were consistent with partial deafness in the older horse group. Conclusion BAER assessment can be used to identify partial deafness in older horses. Such horses should be managed appropriately, with particular care taken in noisy environments where hearing loss could put the horse and/or its owner at risk of harm.     

Unilateral and Bilateral Brainstem Auditory-Evoked Response Abnormalities in 900 Dalmatian Dogs

In a survey of 900 Dalmatian dogs, brainstem auditory-evoked responses (BAER) and clinical observations were used to determine the incidence and sex distribution of bilateral and unilateral BAER abnormalities and their association with heterochromia iridis (HI). To assess the efficacy of BAER testing in guiding breeding programs, data from 749 dogs (subgroup A), considered to be a sample of the population at large, were compared with data from a subgroup (subgroup B; n = 151) in which selection of breeding stock had been based on BAER testing from the beginning of the 4-year survey. Brainstem auditory-evoked responses were elicited by applying click stimuli unilaterally, while applying a white noise masking sound to the contralateral ear. Under these conditions, BAER were either normal, unilaterally absent, or bilaterally absent. Dogs with bilaterally absent BAER were clinically deaf; dogs with unilaterally absent BAER were not clinically deaf but appeared dependent on their BAER-normal ears for their auditory-cued behavior. Dogs with unilaterally absent BAER often were misidentified as normal by uninformed observers. Among the 900 dogs, 648 (72.0%) were normal, 189 (21.0%) had unilateral absence of BAER, and 63 (7.0%) had bilateral absence of BAER or were clinically deaf and assumed to have bilaterally absent BAER (n = 4). Total incidence in the population sampled was assumed to be higher, because some bilaterally affected dogs that would have been members of subgroup A undoubtedly did not come to our attention. Among females, 24.0% were unilaterally abnormal and 8.2% were bilaterally abnormal whereas, among males, 17.8% were unilaterally abnormal and 5.7% were bilaterally abnormal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Retinal detachment in horses: 40 cases (1998-2005)

OBJECTIVE: To determine clinical features, ophthalmic examination findings, etiology, treatment, and outcome of horses diagnosed with retinal detachment (RD). ANIMALS STUDIED: Forty horses, presented to the North Carolina State University and The Ohio State University Veterinary Teaching Hospitals from 1998 to 2005 that were diagnosed with RD. PROCEDURE(S): Horses with documented RD, confirmed either on ophthalmic examination or by ultrasonography, and with a complete medical record were included. Information retrieved from the medical records included signalment, presenting complaint, duration of clinical signs, ophthalmologic examination findings, diagnostics performed, identified cause of the retinal detachment, treatment given, and outcome. RESULTS: Forty horses (46 eyes) were diagnosed with RD. Mean +/- SD duration of clinical signs of ocular disease was 10.5 +/- 14.7 months. Thirty-four horses presented with unilateral involvement, 6 with bilateral, 14 with partial and 32 with complete RD. Ultrasonography was used to make the diagnosis in 26 eyes, while RD was diagnosed on routine ocular examination in 20 eyes. Bullous RD was the only type of RD observed, although small vitreal traction bands were considered secondary to the underlying inflammation or trauma. RD caused by equine recurrent uveitis (ERU) was diagnosed in 27 of 40 (67.5%) horses. Trauma-induced RD involved 10 of the 40 horses (25%). Presenting problems included known ERU (n = 16), acute or progressive vision loss (n = 9), known ocular trauma (n = 6), cataract (n = 6), and a cloudy cornea (n = 3). No horses regained vision after RD despite therapy. Many eyes were enucleated or eviscerated, or the horses were euthanized. Seven eyes with complete RD were noted to be unchanged and comfortable with medical therapy. CONCLUSIONS: The visual prognosis of RD in horses is grave; however, horses with nontraumatic RD (most commonly ERU) may be able to maintain a comfortable but blind globe with anti-inflammatory medical therapy.     

Evaluation of high-speed treadmill videoendoscopy for diagnosis of upper respiratory tract dysfunction in horses

OBJECTIVE: To evaluate high-speed treadmill videoendoscopy as a diagnostic technique and document the abnormalities found in Australian horses referred for poor performance associated with abnormal upper respiratory tract noise but where a definitive diagnosis could not be made at rest. DESIGN: A retrospective clinical study using client-owned horses. PROCEDURE: The clinical records and videorecordings of all horses referred to the University of Sydney for poor performance associated with abnormal upper respiratory tract noise during a 13-month period were examined. Only horses with a normal physical examination including absence of lameness, and where a definitive diagnosis of the cause of the abnormal upper respiratory tract noise could not be made from the resting videoendoscopic examination were included in the study. The age, gender, breed of horse and the purpose for which the horse was used were ascertained from the record and videorecordings were reviewed by the authors and any abnormalities noted. RESULTS: There were 37 horses included in the study. An upper airway abnormality was identified during high-speed treadmill videoendoscopy in 73% of horses. One abnormality was identified in 22 horses, 2 abnormalities in 4 horses and 3 abnormalities in 1 horse. Abnormalities identified included laryngeal hemiparesis (n = 15), axial deviation of the aryepiglottic folds (n = 10), pharyngeal collapse (n = 3), dorsal displacement of the soft palate (n = 2), epiglottic collapse (n = 1), axial deviation of the vocal cord (n = 1) and laryngeal collapse (n = 1). CONCLUSIONS: The results of this study are similar to reports from overseas and suggest high-speed treadmill videoendoscopy appears to be a useful technique to diagnose the cause of upper airway dysfunction in Australian horses referred specifically for poor performance associated with abnormal upper respiratory noise. However, a diagnosis will not be made in all horses undergoing this procedure. There were five horses with two or three abnormalities none of which were apparent at rest. This would suggest that in all horses making abnormal upper respiratory noise associated with poor performance, even where an abnormality is identified at rest, high-speed treadmill videoendoscopy should be performed for a complete diagnosis.     

Surgical treatment of lumbosacral foraminal stenosis using a lateral approach in twenty dogs with degenerative lumbosacral stenosis

Objectives— To describe clinical signs, magnetic resonance imaging (MRI) and surgical findings using a lateral approach to the lumbosacral intervertebral foramen and to evaluate clinical outcomes in dogs with or without concurrent dorsal decompression and annulectomy.
Study Design— Retrospective study.
Animals— Dogs (n=20) with degenerative lumbosacral stenosis (DLSS).
Methods— Medical records (2002–2006) of dogs that had lumbosacral lateral foraminotomy alone or in combination with dorsal decompression were reviewed. Degree of dysfunction was assessed separately for each pelvic limb; dogs with unilateral signs were included in group A, those with bilateral signs in group B. Retrieved data were: signalment, history, neurologic status on admission, 3 days, 6 weeks, and 6 months postoperatively, duration of clinical signs, results of MRI, surgical site(s), intraoperative findings, and outcome.
Results— Based on the clinical and MRI findings unilateral foraminotomy was performed in 8 dogs, bilateral foraminotomy in 1 dog, unilateral foraminotomy with concurrent dorsal decompression in 7 dogs, and bilateral foraminotomy with concomitant dorsal decompression in 4 dogs. Surgery confirmed the presence of foraminal stenosis in all dogs, with osteophyte formation and soft tissue proliferations being the most common lesions. Outcome was good to excellent in 19 dogs and poor in 1 dog. Mean follow-up was 15.2 months (range, 6–42 months).
Conclusion— Lateral foraminotomy addresses compressive lesions within exit and middle zones of the lumbosacral foramen.
Clinical Relevance— Successful surgical management of DLSS is dependent on recognition and correction of each of the compressive lesions within the lumbosacral junction.     

Pull-through technique for palmar digital neurectomy: forty-one horses (1998-2004)

Objectives— To report outcome of horses treated for navicular syndrome using a pull-through (PT) technique for palmar digital neurectomy (PDN).
Design— Retrospective study.
Animals— Horses (n=41) with navicular syndrome (NS).
Methods— Medical records (1998–2002) for horses that had NS and failed to respond to conservative management that had unilateral or bilateral forelimb, biaxial PDN were reviewed. Outcome for up to 6 years was obtained by telephone questionnaire or lameness examination. Survival analysis was used to assess time to recurrence of lameness.
Results— One year after PDN, 36 horses (88%) were free of lameness. Mean survival with no lameness after surgery was estimated at 4.14±0.33 years (median, 5 years).
Conclusions— PT–PDN technique resulted in soundness for 88% of horses for at least 1 year. PT–PDN was easily and quickly performed without specialized equipment, and had a low incidence of complications.
Clinical Relevance— The PT technique is an effective and viable alternative surgical method for PDN.     

Abnormalities of the brainstem auditory response of the dog associated with equilibrium deficit and seizure

The brainstem auditory evoked response (BAER) was recorded from 20 dogs, 10 exhibiting vestibular deficit, and 10 presented with a history of seizures. Two dogs exhibited both types of signs. Abnormalities of the BAER, prolonged interwave latency, were seen in 8 of the 10 animals with vestibular problems, and in 7 of the 10 animals with seizure history. Several different diagnosis were associated with BAER abnormalities in both groups of animals. In 55.5% of the cases exhibiting abnormalities of the BAER, postmortem evidence of brainstem pathology was not detected. The electroencephalogram (EEG) was normal in three instances of abnormalities of the BAER. The BAER was normal in three dogs with abnormalities of the EEG. The BAER is presented as a useful diagnostic tool for brain lesions in animals with vestibular deficit and seizure history, but appears most useful when used in conjuction with the EEG. Correlations of abnormalities of the BAER and clinical course of disease are discussed.Publication No. 1707, School of Veterinary Medicine, Auburn University, AL 36849     

Temporohyoid osteoarthropathy in 33 horses (1993-2000)

A retrospective study of the medical records of 33 horses was performed to determine the clinical and diagnostic abnormalities associated with temporohyoid osteoarthropathy. Data collected from medical records included signalment, presenting complaints, history, physical examination findings, laboratory data, results of diagnostic imaging studies, and treatments. Follow-up information was obtained from a review of case records; by telephone conversation with the owner, veterinarian, or trainer; or by both methods. Of 33 horses with temporohyoid osteoarthropathy, 29 presented with facial nerve (cranial nerve VII) deficits and 23 presented with vestibulocochlear nerve (cranial nerve VIII) deficits. Guttural pouch endoscopy was more reliable than radiography for diagnosis. Of horses with unilateral clinical signs, 22.6% actually had bilateral disease. Magnetic resonance imaging and computed tomography identified the lesions in all horses in which these tests were performed. Of 30 horses for which follow-up information was obtained, 20 (67%) were alive. Eight horses were euthanized and 1 died because of problems associated with temporohyoid osteoarthropathy. Nineteen of 20 surviving horses (95%) were considered by the owner or trainer to be suitable for athletic use. Twelve surviving horses (60%) had residual facial nerve deficits; 11 horses (55%) had residual vestibulocochlear nerve deficits. Horses with temporohyoid osteoarthropathy have a fair prognosis for return to some type of athletic function, but there is risk of acute death. The majority of horses would be expected to have some residual cranial nerve dysfunction, and it could take a year or longer for maximal improvement to occur.     

Cardiovascular changes associated with intravenous administration of fumonisin B1 in horses

OBJECTIVE: To determine whether cardiovascular dysfunction is evident in horses with leukoencephalomalacia experimentally induced by administration of fumonisin B1. ANIMALS: 11 healthy horses of various breeds (body weight, 252 to 367 kg). PROCEDURE: Horses were randomly assigned to 3 groups and administered fumonisin B1 daily. Horses received IV injections of 0 (control horses; n = 4), 0.01 (3), or 0.20 mg (4) of fumonisin B1/kg for 7 to 28 days. Horses were examined daily for evidence of neurologic disease. When neurologic signs consistent with leukoencephalomalacia were evident, horses were anesthetized, and catheters were inserted for evaluation of the cardiovascular system. After recovery from anesthesia, hemodynamic measurements were obtained. RESULTS: Fumonisin-treated horses with clinical signs of neurologic disease had evidence of cardiovascular dysfunction manifested as decreases in heart rate, cardiac output, right ventricular contractility (assessed by measuring the maximal rate of change of right ventricular pressure), coccygeal artery pulse pressure, and pH and base excess in venous blood as well as increases in systemic vascular resistance, compared with values for control horses. Fumonisin-treated horses with and without clinical signs of neurologic disease also had higher serum and right ventricular sphinganine and sphingosine concentrations than control horses. CONCLUSIONS AND CLINICAL RELEVANCE: An association was detected among fumonisin-induced neurologic disease, increased serum and myocardial sphinganine and sphingosine concentrations, and decreased cardiovascular function in horses. Fumonisin-induced decreases in cardiovascular function may contribute to the pathophysiologic development of leukoencephalomalacia in horses.     

Clinical abnormalities detected in post-race examinations of poorly performing Standardbreds

OBJECTIVE: To describe the clinical abnormalities found on post-race examination of poorly performing Standardbreds. METHOD: The results of 541 post-race veterinary examinations on Standardbreds were analysed. The horses were selected for examination by the stipendiary stewards on the basis of poor performance from a population of approximately 20,000 runners which competed at Harold Park Paceway, Sydney. RESULTS: Clinical abnormalities were detected on post-race examination in 264 of the 541 poorly performing horses. Some horses displayed more than one abnormality. Twenty three individual abnormalities were reported. Seventy three horses had suffered interference-type injuries (cross firing, scalping, over reaching) during the race. Lameness was the second most commonly found abnormality (n = 60), with 73% of these lamenesses being in a forelimb. Twenty nine horses had sacroiliac pain (representing 10.6% of the abnormalities detected). Poor recovery, exercise induced pulmonary haemorrhage, respiratory infection or nasal discharge, gluteal pain, unilateral nasal haemorrhage and mouth injuries complete the list of the ten most common findings. CONCLUSION: Interference-type injuries, lameness and sacroiliac pain were the most common abnormalities found on post-race examination of Standardbreds, which performed poorly.     

Biochemical indices of vascular function, glucose metabolism and oxidative stress in horses with equine Cushing's disease

REASONS FOR PERFORMING STUDY: The mechanisms underlying the increased risk of laminitis in horses with equine Cushing's disease (ECD) are poorly understood. HYPOTHESIS: That abnormalities in glucose homeostasis, similar to those which cause microvascular dysfunction in human diabetics, contribute to development of laminitis in horses with ECD. METHODS: Thirty-one aged horses were divided into 3 groups based on clinical signs and dexamethasone suppression testing (DST). Group 1 (n = 12) had clinical ECD as evidenced by hirsutism. Group 2 (n = 10) had a positive DST but no hirsutism. Group 3 (n = 9) were controls without ECD, with a negative DST and no clinical evidence of ECD. Biochemical indices of glucose metabolism, vascular function and oxidative stress were determined in single morning blood samples. RESULTS: Group 1 had abnormalities in glucose homeostasis, including increased levels of glucose and insulin, compared to Groups 2 and 3. Groups 1 and 2 had significantly lower plasma thiol (PSH) levels and nonsignificantly lower albumin-corrected PSH levels than Group 3, consistent with oxidative stress. CONCLUSIONS AND POTENTIAL RELEVANCE: The observed abnormalities in glucose metabolism and oxidative stress could potentially contribute to development of laminitis in horses with ECD, by similar mechanisms to those that cause microvascular dysfunction in human diabetics. The absence of inter-group differences in the biochemical indices of vascular function precludes their use as preclinical diagnostic indicators of vascular dysfunction. The study also highlighted limitations in the premortem diagnosis of ECD.     

Gastric Neoplasia in Horses

Background: Gastric neoplasia of horses is incompletely described.
Objective: Provide history, clinical signs, and clinicopathological and pathological findings associated with gastric neoplasia in horses.
Animals: Twenty-four horses with gastric neoplasia.
Methods: Retrospective study. History, clinical signs, and clinicopathological and pathologic findings in horses diagnosed histologically with gastric neoplasia were reviewed.
Results: Horses ranged in age from 9 to 25 years (median 18 years at presentation). There was no apparent breed or sex predisposition. The most common presenting complaints were inappetance (17/24), weight loss (14/24), lethargy (7/24), hypersalivation (7/24), colic (5/24), and fever (5/24). The most consistent clinical signs were tachypnea (10/19), decreased borborygmi (8/19), and low body weight (7/17). Useful diagnostic tests included rectal examination, routine blood analysis, gastroscopy, abdominocentesis, and transabdominal ultrasound examination. Anemia was the most common hematologic abnormality encountered (7/19), and hypercalcemia of malignancy was seen in 4/16 horses. Squamous cell carcinoma was the most common tumor identified (19/24), and was most often (14/19) found as a single ulcerated, necrotic mass in the nonglandular portion of the stomach. Other gastric neoplasms encountered were leiomyoma (n=2), mesothelioma (n=1), adenocarcinoma (n=1), and lymphoma (n=1). Metastatic neoplasia was found in 18/23 horses. The median time from onset of clinical signs to death was 4 weeks, and all horses died or were euthanized because of gastric neoplasia.
Conclusions: Squamous cell carcinoma is the most common primary gastric neoplasia in horses. The survival time after diagnosis of gastric neoplasia in horses is short.     

Pneumothorax in horses: 40 cases (1980-1997)

OBJECTIVE: To characterize pneumothorax in horses and to describe clinical signs, diagnostic testing, and clinical outcome of horses with pneumothorax. DESIGN: Retrospective study. ANIMALS: 40 horses. PROCEDURE: Medical records of horses with pneumothorax were reviewed to obtain information on signalment, history, clinical signs, diagnostic testing, treatment, and clinical outcome. RESULTS: Horses developed pneumothorax secondary to pleuropneumonia (17 horses), open wounds of the thorax (9), closed trauma to the thorax (7), surgery on the upper portion of the respiratory tract (3), and surgery involving the thoracic cavity (1); 3 horses had pneumothorax of unknown cause. Clinical signs included tachypnea, dyspnea, cyanosis, lack of lung sounds on auscultation of the dorsal aspect of the thorax, fever, tachycardia, signs of depression or anxiousness, and cough. Radiography and ultrasonography were useful to definitively diagnose pneumothorax. Pneumothorax was bilateral in 47.5% (19/40) and unilateral in 42.5% (17/40) of horses; designation of unilateral versus bilateral was not recorded in the remaining 4 horses. Horses with pneumothorax secondary to pleuropneumonia more commonly had unilateral pneumothorax (64.7% for unilateral vs 29.4% for bilateral; not specified for 1 horse). Horses with pneumothorax secondary to pleuropneumonia were less likely to survive than horses with pneumothorax secondary to other causes (35.3 vs 69.6% survived, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Pleuropneumonia is an important cause of pneumothorax in horses. Classic clinical signs of pneumothorax may not be evident. Radiography, ultrasonography, or both may be required for diagnosis. Prognosis for survival is better for horses with pneumothorax not associated with pleuropneumonia.     

Neurologic abnormalities and cerebrospinal fluid changes in horses administered fumonisin B1 intravenously

The objective of this experiment was to characterize a dose-dependent toxic effect of fumonisin B1 (FB1) and to document initial neurologic signs, clinical progression, and terminal cerebrospinal fluid (CSF) changes in horses administered FB1 IV. Seventeen healthy horses were administered 0.00 (n = 4), 0.01 (n = 3), 0.05 (n = 3), 0.10 (n = 3), or 0.20 mg (n = 4) of purified FB1 IV q24h. When neurologic abnormalities observed by a masked observer became severe, atlanto-occipital CSF taps were performed and CSF pressure, cell count, cytology, protein, albumin and glucose concentrations, and creatine kinase activity were measured. Changes in CSF and number of days to 1st observation of neurologic abnormalities were compared between doses by ANOVA, with the level of significance set at P < .05. Control horses and low-dose horses (0.01 mg/kg) remained neurologically normal. In higher dose FB1-treated horses (n = 10), initial clinical signs (days 4-10) included hindlimb ataxia, delayed forelimb placing, and decreased tongue tone and movement. Hindlimb and trunkal ataxia, depression, hyperesthesia, and intermittent dementia gradually became apparent. When data from all horses with neurologic abnormalities were pooled (0.05-0.20 mg/kg FB1), mild clinical signs (mean day 6.3) occurred significantly earlier than did more severe (mean day 8.9) clinical signs (P = .009). Neurologic horses had high CSF protein, albumin, and IgG concentrations and increased albumin quotients (P < .05). It was concluded that FB1-induced neurologic and CSF changes in a dose-dependent manner, with a no-observable-limit of 0.01 mg FB1/kg IV q24h for 28 days. The neurologic and CSF changes were consistent with vasogenic cerebral edema.     

Transarterial coil embolisation in 31 horses (1999-2002) with guttural pouch mycosis: a 2-year follow-up

REASONS FOR PERFORMING STUDY: There have been no previously published large case series describing short- and long-term outcome of transarterial coil embolisation (TCE) in horses with guttural pouch mycosis (GPM). OBJECTIVES: To describe the clinical and surgical features of horses with GPM presented at the Veterinary School of Lyon during a 28 month period; and to evaluate immediate to long-term results of TCE as a treatment. METHODS: Medical records of all horses with GPM treated with TCE between February 1999 and July 2002 were analysed. To be included in the study, no other surgical or medical treatment for the mycosis was administered. Subject details, case history and results of initial clinical examination and endoscopy were reviewed. For all individuals, evaluation of long-term complications and case evolution was based on owner or trainer interviews between 24 and 41 months after surgery. RESULTS: Thirty-one horses were identified with unilateral (n = 25) or bilateral (n = 6) GPM affecting only the medial (n = 28), only the lateral (n = 2) or both compartments simultaneously (n = 7). Of the 23 individuals presented with epistaxis, 20 showed complete resolution of the problem. Of the 19 horses presented with neurological signs, 2 were subjected to euthanasia for persistence of severe dysphagia. Prognosis for survival was excellent (84%) and prognosis for return at the level expected by the owner or trainer was good (71%). CONCLUSIONS AND POTENTIAL RELEVANCE: TCE of horses affected with GPM is an effective method of preventing haemorrhage and resolving the majority of mycotic lesions without further specific treatment. Treated horses did not present relapse of mycosis during the follow-up period.     

Sensitivity and specificity of western blot testing of cerebrospinal fluid and serum for diagnosis of equine protozoal myeloencephalitis in horses with and without neurologic abnormalities

OBJECTIVE: To determine sensitivity and specificity of western blot testing (WBT) of CSF and serum for diagnosis of equine protozoal myeloencephalitis (EPM) in horses with and without neurologic abnormalities. DESIGN: Prospective investigation. ANIMALS: 65 horses with and 169 horses without neurologic abnormalities. PROCEDURE: CSF and serum from horses submitted for necropsy were tested for Sarcocystis neurona-specific antibody with a WBT. Results of postmortem examination were used as the gold standard against which results of the WBT were compared. RESULTS: Sensitivity of WBT of CSF was 87% for horses with and 88% for horses without neurologic abnormalities. Specificity of WBT of CSF was 44% for horses with and 60% for horses without neurologic abnormalities. Regardless of whether horses did or did not have neurologic abnormalities, sensitivity and specificity of WBT of serum were not significantly different from values for WBT of CSF. Ninety-four horses without EPM had histologic evidence of slight CNS inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: The low specificity of WBT of CSF indicated that it is inappropriate to diagnose EPM on the basis of a positive test result alone because of the possibility of false-positive test results. The high sensitivity, however, means that a negative result is useful in ruling out EPM. There was no advantage in testing CSF versus serum in horses without neurologic abnormalities. Slight CNS inflammation was common in horses with and without S neurona-specific antibodies in the CSF and should not be considered an indication of CNS infection with S neurona.     

Surgical Treatment of Mineralized and Nonmineralized Supraspinatus Tendinopathy in Twenty-four Dogs

Objective— To report and compare the clinical diagnosis, surgical treatment, histopathologic changes, and outcomes of dogs with mineralized and nonmineralized supraspinatus tendinopathy (ST).
Study Design— Case series.
Animals— Dogs (n=24) with ST.
Methods— Medical records (1995–2006) of dogs with ST that had surgical treatment were reviewed. Results of clinical examination, diagnostic imaging, surgery, histopathology of resected tendon tissue, and outcome were compared between dogs with mineralized and nonmineralized ST.
Results— There were 15 dogs with mineralized ST and 9 with nonmineralized ST. Chronic, unilateral, intermittent or waxing-waning lameness, and pain elicited on palpation of the cranial aspect of the shoulder were the most consistent findings. On ultrasonographic or magnetic resonance imaging (MRI) of 35 shoulders, enlargement of the supraspinatus tendon (54%), increased fluid content (63%), and medial displacement of the biceps tendon (60%) were observed. Eleven of 12 dogs with bilateral abnormalities only had unilateral lameness. Surgery was performed in 30 shoulders. Resected tendon specimens had myxomatous degeneration and/or cartilaginous metaplasia in 11 of 13 dogs in the mineralized group and all 9 dogs in the nonmineralized group. Functional outcome after surgery was poor in 3 dogs and good-to-excellent in 16.
Conclusions— Mineralized and nonmineralized ST have many similarities. Although lameness is usually unilateral, the supraspinatus tendon may be affected bilaterally.
Clinical Relevance— Ultrasonography and MRI are good imaging techniques for detection of ST especially the nonmineralized form. Surgical treatment results in good recovery of limb function. Nonmineralized ST is a recently described disorder in dogs and evaluation of more cases is necessary to determine outcome after surgical or medical treatment.     

Congenital ocular abnormalities of Rocky Mountain Horses

Objective: To determine the incidence and describe ocular abnormalities in a cross-section of the population of Rocky Mountain Horses.
Design: Prospective study.
Animals: Five-hundred and fourteen Rocky Mountain Horses.
Procedure: Ophthalmic examinations were performed using a slit-lamp biomicroscope and an indirect ophthalmoscope. Intraocular pressures were measured by applanation tonometry. Eyes from six horses were obtained for histologic examination.
Results: Cysts of the posterior iris, ciliary body, and peripheral retina were detected most frequently (249 horses), and were always located temporally. Curvilinear streaks of retinal pigmented epithelium extending from the peripheral temporal retina marked the boundary of previous retinal detachment in 189 horses. Retinal dysplasia was detected in 125 horses. Multiple ocular anomalies were evident in 71 horses and were always bilateral and symmetrical. Affected eyes had a large, clear cornea that protruded excessively and had an apparent short radius of curvature, a deep anterior chamber, miotic and dyscoric pupil, and iris hypoplasia. Pupillary light responses were decreased or absent and pupils failed to dilate after repeated instillation of mydriatic drugs in horses with multiple ocular anomalies. Less frequently encountered abnormalities included peripheral iridocorneal adhesions and goniosynechiae. Congenital cataract was always present in eyes with multiple abnormalities. Intraocular pressures did not differ among horses with normal eyes and horses with multiple ocular abnormalities. Histologic examination of eyes corroborated the clinical appearance.