Horner syndrome as a physiological biomarker of disease in canine cervical myelopathy.

BACKGROUND: Horner syndrome often occurs with cervical myelopathies and might provide insight into the underlying disease and prognosis. OBJECTIVES: To describe the clinical and imaging features of dogs with cervical myelopathy and concurrent Horner syndrome and to determine association of Horner syndrome with diseases or magnetic resonance images (MRI). ANIMALS: Ninety-three client-owned dogs with cervical myelopathy and concurrent Horner syndrome and 99 randomly selected client-owned dogs with cervical myelopathy without Horner syndrome (control cases). METHODS: Retrospective study. Medical records were reviewed to identify Horner and control cases and clinical findings recorded. MRI were reviewed, and lesions characterized and recorded. Descriptive and comparative statistics were performed. RESULTS: Non-compressive disease occurred more frequently in the Horner group compared with controls (58%; 95% CI: 48-68 vs 9%; 95% CI: 5-16; P < .0001). The most common diseases were fibrocartilaginous embolism in the Horner group (44/93; 47%) and intervertebral disc extrusion (76/99; 77%) amongst controls. On MRI, parenchymal hyperintensity was seen more commonly in the Horner group (95%; 95% CI: 88-98) compared with controls (51%; 95% CI: 41-60; P < .0001). In the Horner group, dogs that did not survive to discharge (N = 13) had more extensive MRI lesions relative to the adjacent vertebral length (200%; IQR 110%-575%) compared with survivors (N = 80; 110%; IQR 40%-250%; P = .02). Lateralization of Horner signs and MRI changes matched in 54% of cases. The overall survival rate was high in both Horner (80/93; 86%) and control (95/99; 96%) groups. CONCLUSIONS AND CLINICAL IMPORTANCE: Horner syndrome in cervical myelopathy is commonly associated with noncompressive intraparenchymal disease.

Bilateral cholesterol granulomas in the middle ear cavities of a cat with sinonasal disease successfully removed via video-otoscopy.

CASE DESCRIPTION: A 9-year-old spayed female Maine Coon cat was presented at the University of Veterinary Medicine Vienna for further investigation of chronic nonpruritic bilateral ear disease and unilateral Horner syndrome. CLINICAL FINDINGS: Physical examination and otoscopy findings included right sided Horner syndrome, a right head tilt of approximately 20° and a small pink nodule in the right and several smaller nodules in the left proximal horizontal external ear canal. Computed tomography and magnetic resonance imaging revealed soft tissue opacity material in both middle ear cavities, the caudal portion of the nasal cavity, the left nasopharyngeal meatus and the right frontal sinus. Via videootoscopy, 2 multilobular and several flat nodules were detected in the proximal right horizontal external ear canal and in the left tympanic bulla, respectively. Histopathological examination confirmed the diagnosis of cholesterol granulomas. TREATMENT AND OUTCOME: All otic cholesterol granulomas (CGs) were removed via video-otoscopy (VO), and topical treatment was initiated in addition to oral prednisolone. After the histopathological confirmation, negative microbial cultures from the middle ear cavities, and the remission of the symptoms by the first recheck, topical, and systemic treatment were discontinued. A follow-up 6 months later, did not reveal any recurrence of the CGs. CLINICAL RELEVANCE: To our knowledge, this is the first case of bilateral CGs diagnosed with a combination of CT, MRI, VO, and histopathology and removed minimal invasively via VO, without a need for ventral bulla osteotomy, which led to complete remission of all signs and no relapse until the follow up 6 months later.

Neurogenic keratoconjunctivitis sicca in 34 dogs: A case series.

OBJECTIVE: To describe the clinical findings, imaging features, underlying conditions, treatment, and progression of dogs presented between 2010 and 2019 with neurogenic keratoconjunctivitis sicca (NKCS). METHODS: Dogs diagnosed with NKCS were searched in the clinical database. Inclusion criteria were STT-1 readings <15 mm/min, clinical signs of KCS with concurrent ipsilateral xeromycteria. RESULTS: Thirty-four cases were identified. Mean age at presentation was 8.2 years, median 8.9 years (0.3-14.7). Twenty dogs were male, and 14 dogs were female. Concurrent neurological deficits included facial neuropathy (n = 13, 38%), peripheral vestibular syndrome (n = 10, 29%), and Horner's syndrome (n = 5, 15%). Advanced imaging was acquired in 53% of cases (n = 18). Etiologies included idiopathic (n = 18, 53%), endocrinopathy (n = 6, 18%), otitis interna (n = 4, 12%), head trauma (n = 3, 9%), iatrogenic (post-TECA-LBO, n = 1, 3%), brainstem mass (n = 1, 3%), and an area of inflammation in the pterygopalatine fossa (n = 1, 3%). Treatment for NKCS was initiated in most cases (n = 30, 88%) including: oral pilocarpine 2% and lacrimostimulant (n = 19), oral pilocarpine 2% only (n = 3), or lacrimostimulant only (n = 8). A mean time follow-up of 3.7 months, median 3 months (1-14) was available in 23 cases (68%). Eleven cases with follow-up were responsive (48%) with resolution of the clinical signs in a median time 4 months (1-10), and all of them were treated with oral pilocarpine (±lacrimostimulant). CONCLUSIONS: Most cases presented as idiopathic NKCS; in others, an underlying cause of facial neuropathy was identified. All responsive cases were treated with oral pilocarpine 2%.

The diagnostic yield of advanced imaging in dogs with Horner's syndrome presenting with and without additional clinical signs: A retrospective study of 120 cases (2000-2018).

PURPOSE: To evaluate the diagnostic yield of advanced imaging in dogs with Horner's syndrome (HS) both with and without additional clinical signs. METHODS: Retrospective review of clinical records from a UK referral hospital (2000-2018). Cases were excluded if HS was trauma- or surgery-related and if no advanced imaging with MRI or CT was performed. Imaging findings were assessed as well as any additional investigations performed. RESULTS: One hundred twenty cases met the inclusion criteria; 88 with additional clinical signs and 32 with isolated HS. MRI or CT of head and neck was performed in 115 cases and/or thoracic CT in eight cases. Causative lesions were identified in 98% (86/88) of cases with additional clinical signs and 3% (1/32) of cases with isolated HS. This was statistically significant (p < .001). Pharmacological localization using phenylephrine (0.1%-10%) was accurate in predicting the site of a causative lesion in 79% (19/24) of tested cases. Overall, 28% (33/120) of cases were idiopathic, of which 49% (16/33) were golden retrievers. When compared to the overall hospital population, and UK Kennel Club records, this confirmed a significant predisposition in this breed (p < .001). No associations between idiopathic HS and concurrent systemic disease were identified. CONCLUSION: This is the first study to evaluate the diagnostic yield of advanced imaging in dogs with HS. Isolated HS is significantly more likely to be idiopathic than cases presenting with additional clinical signs; this could guide decision-making regarding further investigations performed in a clinical setting. Idiopathic HS is over-represented in the golden retriever.

Ultrasound-guided brachial plexus block and suspected Horner's syndrome in an alpaca (Vicugna pacos) undergoing traumatic scapulo-humeral luxation reduction and articular capsule reconstruction.

Background: Alpacas are becoming more and more diffused as pets in Europe and United Kingdom, and it is not uncommon to deal with these species in large animal referral hospitals. Unfortunately, pain assessment and treatment in llamoids remain challenging, due to their instinct of hiding signs of pain and the lack of relevant scientific literature. Case Description: This report describes the use of an ultrasound-guided brachial plexus block as part of a multimodal analgesic strategy in an alpaca undergoing surgical right shoulder luxation repair. Based on the intra-operative cardiovascular stability, the post-operative comfort level, and the minimal amount of systemic analgesics needed, it can be concluded that the block appeared effective and contributed to the peri-operative pain management. After recovery from general anesthesia, drooping of the right upper eyelid was observed and persisted for approximately 10 hours. This finding could be interpreted as a Horner's syndrome-like clinical sign and be a minor complication of the block, as previously described in other species. Conclusion: Despite the minor complication here reported, and the difficulty in assessing intra- and post-operative nociception and pain in camelids, it can be concluded that the use of a brachial plexus block could be a valuable option when desensitization of the forelimb is required.

Transient Horner's syndrome and ipsilateral facial hypopigmentation in an acromelanistic cat.

Horner's syndrome (HS) occurs when the sympathetic nerve pathway is disrupted. This case report describes a cat with acromelanism that developed unilateral facial hypopigmentation concurrently with HS after an oesophagostomy tube was placed. Both the hypopigmentation and HS resolved completely following removal of the oesophagostomy tube.

Le syndrome de Horner (HS) survient lorsque la voie nerveuse sympathique est perturbée. Ce rapport de cas décrit un chat atteint d'acromélanisme qui a développé une hypopigmentation faciale unilatérale en même temps qu'une HS après la mise en place d'une sonde d'oesophagostomie. L'hypopigmentation et l'HS ont disparu complètement après le retrait de la sonde d'œsophagostomie.

El síndrome de Horner (HS) ocurre cuando se interrumpe la transmisión nerviosa a través del nervio simpático. Este caso clínico describe un gato con acromelanismo que desarrolló hipopigmentación facial unilateral al mismo tiempo que HS después de la colocación de una sonda de esofagostomía. Tanto la hipopigmentación como la HS se resolvieron por completo tras la retirada del tubo de esofagostomía.

A síndrome de Horner (SH) ocorre quando a via do nervo simpático é danificada. Este relato de caso descreve um gato com acromelanismo que desenvolveu hipopigmentação facial unilateral concomitantemente com SH após a colocação de um tubo de esofagostomia. Tanto a hipopigmentação quanto a HS se resolveram completamente após a remoção do tubo de esofagostomia.

Horner Syndrome With Ipsilateral Wing Paresis in a Wild, Juvenile Yellow-Tailed Black Cockatoo (Calyptorhynchus funereus).

A juvenile yellow-tailed black cockatoo (Calyptorhynchus funereus) was presented with paresis of the right wing, ptosis, and miosis of the right eye; feather erection of the right side of the head and neck; and a penetrating injury over the right pectoral muscle. Temporary reversal of ptosis, miosis, and feather erection after administration of phenylephrine drops confirmed a diagnosis of Horner syndrome. Computed tomographic imaging revealed a fractured rib, traumatic lung lesions, and subcutaneous emphysema. The right-sided Horner syndrome and wing paresis were attributed to a sympathetic nerve trauma of the eye and feathers and to the brachial plexus, respectively. This report describes the diagnosis and resolution of ptosis and miosis within 8 weeks and recovery of feather symmetry and wing function within 11 weeks of the cockatoo's initial presentation with a conservative-management treatment plan.

Horner Syndrome in Birds of Prey.

Horner syndrome, which results from oculosympathetic denervation, has rarely been reported in birds. A retrospective study was conducted in a raptor rehabilitation program to gain further insight into Horner syndrome in birds. Data from 5128 live raptors admitted over 20 years were reviewed. Horner syndrome was identified in 22 individuals from 13 different species. Raptors from the orders Strigiformes, Accipitriformes, and Falconiformes were affected, with the last order being underrepresented. Ptosis of the upper eyelid was the most commonly reported clinical sign in the birds diagnosed with Horner syndrome, having been noted in 21 cases. Signs of traumatic injury, such as fractures, wounds, and hematomas, were documented in 18 cases. Among the 22 cases, 12 birds were euthanatized, 3 died in treatment, and 7 were successfully released back into the wild.

Retrospective analysis of ocular neuropathies in diabetic dogs following cataract surgery.

OBJECTIVES: To describe and compare the cumulative incidence and clinical progression of ocular neuropathies in diabetic dogs vs nondiabetic dogs following cataract surgery. METHODS: Medical records of 196 diabetic and 442 nondiabetic dogs who underwent cataract surgery between 2004 and 2015 were reviewed. The percentage of patients affected by neuropathy and potential risk factors were compared between groups. RESULTS: Patients with diabetes mellitus (DM) were 20.4 times more likely to develop an ocular neuropathy than patients without DM (12.24% vs 0.68%). Twenty-four diabetic patients were affected by mononeuropathies or polyneuropathies including Horner's syndrome (n = 20), facial neuropathy (n = 5), and neurogenic keratoconjunctivitis sicca (NKCS) (n = 5). The odds of a diabetic patient developing Horner's syndrome and NKCS were 86.3 and 20.7 times higher than a nondiabetic patient, respectively. The average duration of DM prior to diagnosis of neuropathy was 659 days (range 110-2390 days; median 559 days). Complete resolution was achieved in 10 of 22 neuropathies (45%) within an average of 248 days (range 21-638 days; median 187 days) after diagnosis. CONCLUSIONS: The odds of developing an ocular neuropathy, specifically Horner's syndrome and NKCS, are statistically higher in diabetic patients compared to nondiabetic patients. Neuropathies were observed as a long-term complication in this group of diabetic patients, and complete resolution of the neuropathy was observed in less than half of the affected population.

A Retrospective Study of Horner Syndrome in Australian Wild Birds, 2010-2016.

Horner syndrome was identified in 25 of 30 777 avian admissions to Currumbin Wildlife Hospital during 2010-2016. Unilateral ptosis and erection of facial feathers were distinct findings on physical examination and consistent across 9 species. Affected birds were biased toward adults (64%) suffering traumatic injuries (88%). Concurrent injuries requiring treatment were present in 38% of cases, and 76% had additional neurologic deficits. Prognosis for release was poor, with an overall success rate of 32%. Resolution of clinical signs increased to 44% with higher doses of meloxicam and required an average hospitalization of 22 days (range, 3-78 days). Further investigation of the underlying causes of Horner syndrome in birds to provide treatment and prognostic guidelines is warranted.

Tumor maligno da bainha perineural retrobulbar e intracraniano em cão: relato de caso / Malignant neoplasm of the perineural sheath retrobulbar and intracranial in dog: case report

Os tumores da bainha perineural são pouco frequentes em animais domésticos. Relata-se o caso de um cão, sem raça definida, de cinco anos, fêmea, com histórico de aumento de volume em região retrobulbar do globo ocular direito (GOD) havia três semanas. Ao exame clínico, constatou-se a presença de uma neoformação retrobulbar direita com deslocamento do globo ocular cranialmente. Aos exames realizados durante o internamento, não foi possível localizar a origem e a extensão da neoformação. O animal veio a óbito por parada cardiorrespiratória e foi encaminhado para a necropsia. À avaliação macroscópica, observou-se neoformação esbranquiçada fixada à base do crânio em região selar, com possível origem no terceiro (III) par de nervos cranianos, a qual se infiltrava no encéfalo na altura do hipotálamo, estendia-se caudalmente em direção ao tronco encefálico e cranialmente à órbita direita, comprimindo, assim, o GOD. Microscopicamente consistia de feixes curtos entrelaçados ou enovelados de células fusiformes com pleomorfismo discreto a moderado, alternando-se a áreas de necrose multifocalmente, compatível com tumor da bainha perineural. Ao exame imuno-histoquímico, apresentou marcação fraca para S100 e GFAP e marcação positiva para vimentina, o que indica caráter maligno.(AU)

Tumors of the perineural sheath are uncommon in domestic animals. We report the case of a 5-year-old female dog with a history of increased volume in the retrobulbar region of the right eye (RE) three weeks ago. The clinical examination revealed a presence of a right retrobulbar neoformation with cranial ocular globe displacement. In the examinations carried out during hospitalization, it was not possible to locate a source and an extension of the neoformation. The animal died of cardiorespiratory arrest and was referred to an autopsy. The macroscopic evaluation revealed a whitish neoformation fixated to the base of the skull in a seal region, with a possible non-III origin of cranial nerves, infiltrating non-encephalon at the height of the hypothalamus, extending caudally towards the brainstem and cranially to the orbit right, compressing RE. Microscopically it consisted of short bundles intertwined or enovelados of spindle cells with discrete to moderate pleomorphism, alternating to areas of multifocal necrosis, compatible with tumor of the perineural sheath. Immunohistochemical examination showed weak marking for S100 and GFAP and positive marking for vimentin, indicating malignancy.(AU)

Horner Syndrome in 2 Pigs (Sus scrofa) after Vascular Grafting of the Carotid Artery and Jugular Vein.

The term Horner syndrome refers to the clinical presentation of oculosympathoparesis, comprising miosis, ptosis, and facial anhydrosis. To date, there are 2 reports of postoperative Horner syndrome in pigs. In this species the cervical sympathetic chain and cranial cervical sympathetic ganglion are consistently within the carotid artery sheath. This case study describes the sudden onset of Horner syndrome in 2 pigs, from a study cohort of 8, after the placement of a vascular graft between the carotid artery and external jugular vein. Anesthesia and surgery was uneventful in all the pigs in the study, but 2 pigs demonstrated clinical signs including ptosis, enophthalmos and prolapse of the nictitating membrane immediately after recovery from anesthesia. Horner syndrome was diagnosed in light of the clinical signs. These clinical signs persisted throughout the 2-mo study period and did not appear to improve or deteriorate in that time. Gross examination of the surgery site at the end of the study did not reveal an obvious lesion in the carotid artery sheath. The risk of Horner syndrome after surgery involving the carotid artery in pigs had not been reported prior to this study. Without specific measures to protect the cervical sympathetic ganglion during surgery, the incidence of postoperative Horner syndrome was 25% in our population of pigs. Although the welfare implications of this syndrome are minimal, concerted effort to avoid intraoperative damage to the cervical ganglion is essential for future work.

Disseminated peripheral neuroblastoma in a Rhodesian Ridgeback dog.

CASE REPORT: A 4-year-old neutered male Rhodesian Ridgeback dog with right-sided Horner's syndrome, bilateral laryngeal paralysis, neck pain and bilateral hindlimb ataxia was euthanased following deterioration of its neurological status. Necropsy examination revealed an off-white retropharyngeal neoplastic mass (100 × 30 × 30 mm) attached to the base of the skull on the right side and macroscopic nodular metastases in the spleen and three vertebral bodies (C6, C7 and T6), including a nodule attached to the dura at C7. Histological evidence of neuroblastic tumour was detected in these macroscopic lesions, a regional lymph node, bone marrow of a femur and all 15 vertebral bodies (C1-T8) examined, including the three with macroscopic metastases, and in the lumens of small blood vessels in the lungs and liver. Ganglion cell differentiation was detected only in the primary retropharyngeal mass, one splenic nodule and the C7 dural nodule. Neoplastic cells were immunoreactive to neurofilament protein (ganglion cells only), vimentin and synaptophysin, and were negative for S100 protein, GFAP, CD3 and Pax5. CONCLUSION: The diagnosis was disseminated peripheral neuroblastoma, differentiating subtype (International Neuroblastoma Pathology Classification), with likely primary involvement of the right cranial cervical ganglion. This appears to be the first report of neuroblastoma in a dog with widespread occult haematogenous metastasis to bone marrow.

Neuropharmacological lesion localization in idiopathic Horner's syndrome in Golden Retrievers and dogs of other breeds.

OBJECTIVE: To investigate whether idiopathic Horner's syndrome (HS) in Golden Retrievers is an exclusively preganglionic disorder based on denervation hypersensitivity pharmacological testing with phenylephrine. ANIMALS STUDIED: Medical records of dogs presented with HS between 2000 and 2012. Dogs presented with additional ocular or systemic signs were excluded. PROCEDURES: Clinical data examined included age, sex, duration of clinical signs, ancillary diagnostic test results, and time to mydriasis on topical ocular application of 1% phenylephrine. Lesions were diagnosed as postganglionic (mydriasis within 20 min) or preganglionic (mydriasis between 20 and 45 min). RESULTS: Medical records of 21 dogs of nine different breeds were included. An etiopathogenesis for Horner's syndrome was determined in five dogs, none of which were Golden Retrievers. All diagnoses correlated with pharmacological lesion localization. Ten Golden Retrievers were included (eight male and two female) with a mean age of 8.5 years (range: 4-13). Lesion localization was diagnosed as postganglionic in eight (mean: 10 min [range: 6-18]) and preganglionic in two Golden Retrievers (20 and 24 min). All cases were unilateral and had completely resolved within 15 weeks (range: 11-20). Recurrence was not reported in any of the patients. CONCLUSIONS: Idiopathic postganglionic HS was diagnosed in eight of 10 Golden Retrievers contradicting previous reports of a purely preganglionic localization. Etiopathogenesis of canine idiopathic HS remains to be determined; nevertheless, a vascular etiology cannot be excluded. Future studies using magnetic resonance angiography may aid in clarifying the pathogenesis.