Severe orbital hematoma with third eyelid swelling and prolapse following a blind maxillary nerve block in a horse.

A 20-year-old quarter horse gelding was presented for routine dental examination. Periodontal disease and luxation of tooth 108 was diagnosed and oral extraction was planned. After an unsuccessful blind maxillary nerve block, it was elected to perform the procedure under total intravenous anesthesia. Following recovery, a focal superficial corneal ulcer, severe retrobulbar swelling, mild exophthalmos, and marked swelling and prolapse of the third eyelid (nictitating membrane) were observed. Clinical signs persisted beyond 48 h despite the use of systemic anti-inflammatories and topical ocular anti-inflammatories and antibiotics. A temporary tarsorrhaphy was subsequently done at 48 h and the horse was discharged after 5 d of hospitalization and regression of clinical signs. Although it is very useful for easing dental extractions, the blind maxillary nerve block is associated with potential complications due to inadvertent vascular puncture. This case report describes a rare complication of prolapse of the third eyelid in a horse after a maxillary nerve block and successful treatment with a temporary tarsorrhaphy. Key clinical message: This case report explains how nictitating membrane swelling and prolapse can occur following a blind maxillary nerve block in the horse and describes treatment with a temporary tarsorrhaphy.

Hématome orbitaire sévère avec gonflement de la troisième paupière et prolapsus à la suite d'un bloc du nerf maxillaire à l'aveugle chez un cheval. Un hongre quarter horse de 20 ans a été présenté pour un examen dentaire de routine. Une maladie parodontale et une luxation de la dent 108 ont été diagnostiquées et une extraction orale a été planifiée. Après l'échec d'un bloc du nerf maxillaire à l'aveugle, il a été décidé d'effectuer la procédure sous anesthésie intraveineuse. Après la guérison, un ulcère cornéen superficiel focal, un gonflement rétrobulbaire sévère, une légère exophtalmie ainsi qu'un gonflement et un prolapsus marqués de la troisième paupière (membrane nictitante) ont été observés. Les signes cliniques ont persisté au-delà de 48 heures malgré l'utilisation d'anti-inflammatoires systémiques et d'anti-inflammatoires oculaires topiques et d'antibiotiques. Une tarsorraphie temporaire a ensuite été réalisée à 48 heures et le cheval est sorti après 5 jours d'hospitalisation et de régression des signes cliniques. Bien qu'il soit très utile pour faciliter les extractions dentaires, le bloc du nerf maxillaire à l'aveugle est associé à des complications potentielles dues à une ponction vasculaire involontaire. Ce rapport de cas décrit une complication rare de prolapsus de la troisième paupière chez un cheval après un bloc nerveux maxillaire et un traitement réussi par tarsorraphie temporaire.Message clinique clé:Ce rapport de cas explique comment un gonflement et un prolapsus de la membrane nictitante peuvent survenir à la suite d'un bloc du nerf maxillaire à l'aveugle chez le cheval et décrit le traitement par tarsorraphie temporaire.(Traduit par Dr Serge Messier).

Association of FGF4L1 Retrogene Insertion with Prolapsed Gland of the Nictitans (Cherry Eye) in Dogs.

Cherry eye is the common name for prolapse of the nictitans gland, a tear-producing gland situated under the third eyelid of dogs. Cherry eye is characterized by a red fleshy protuberance in the corner of the eye, resembling a cherry. This protrusion is a displacement of the normal gland of the third eyelid, thought to be caused by a defect in the connective tissue that secures the gland in place. Options for treatment may include anti-inflammatory medications in mild cases, but surgical replacement of the gland is usually indicated. Cherry eye is most often seen in dogs under the age of two years, with certain breeds having a higher incidence, suggesting a potential genetic association. Integration of panel genetic testing into routine clinical practice allows for the generation of large numbers of genotyped individuals paired with clinical records and enables the investigation of common disorders using a genome-wide association study (GWAS) approach at scale. In this investigation, several thousand cases and controls for cherry eye in both purebred dogs and mixed breeds are used for a large-scale GWAS, revealing a single peak of genome-wide significance on canine chromosome 18, directly at the location of the previously identified FGF4 insertion known to cause chondrodysplasia in several breeds.

Tumor-like lymphoplasmacytic conjunctivitis in the third eyelid in a dog.

This report aims to describe a case of tumor-like lymphoplasmacytic conjunctivitis in a 7-year-old spayed-female Pomeranian. On complete ophthalmic examination, a mass with papillary projections was noted on the bulbar surface of the right third eyelid. Debulking of the mass was performed while preserving as much of the third eyelid as possible. On the histopathological examination, the mass was diagnosed as lymphoplasmacytic conjunctivitis with mild epithelial hyperplasia. Although a slight regrowth of the mass was noted 3 weeks after surgery, intralesional injection of triamcinolone acetonide led to its disappearance. There was no further recurrence after 5 months.

Challenges in diagnosing canine spindle cell tumours using immunohistochemistry, illustrated by three nonpigmented malignant cases from the nictitating membrane.

BACKGROUND: Nonpigmented malignant spindle cell tumours of the membrana nictitans are rare in dogs. In twenty-three years only three cases have been diagnosed in Scandinavia. This study describes the three cases of malignant tumours of the membrana nictitans recorded by the Eye Pathology Section, University of Copenhagen, Denmark, with reference to the clinical appearance and work-up, the treatment and prognosis, and the histopathological description including immunohistochemistry. The three cases are compared to previous publications on canine tumours of the nictitating membrane. We emphasize the importance of using protocols that are adapted to the specific species such as dogs. Opposite the human tissue responses, we even need more than one marker when diagnosing melanomas in dogs. RESULTS: The dogs presented were an 8-year-old Dachshund, a 12-year-old Akita and a 14-year-old Shetland Sheepdog. All three dogs were entire females. All three nictitating membrane tumours developed on the right nictitating membrane as firm or multilobulated hyperaemic masses. Two of the tumours were macroscopically nonpigmented, the third being partly pigmented on the surface and ulcerated. According to the histopathology and for two of the cases immunohistochemistry with dog-adapted protocols the diagnoses included one hemangiosarcoma and two amelanotic melanomas. Tumour regrowth developed in all three cases and repeated resections were completed 1, 2 and 3 times, respectively, with recurrence experienced within 1.5 months - 3 years. CONCLUSIONS: Nonpigmented malignant spindle cell tumours of the canine membrana nictitans are rare. Treatment of choice should be complete excision with a minimal histologic tumour-free distance and in case of a recurrence a full resection of the nictitating membrane. We strongly recommend a dog-adapted protocol for immunohistochemistry.

Standing sedation management of a domesticated reindeer for third eyelid removal.

Background: Reindeer are becoming popular animals within petting farms. Few case reports describe the sedation of domesticated reindeer, but none describe the use of ocular local anesthetic blocks in this species. Case Description: A 9-year-old, female, Svalbard reindeer (Rangifer tarandus platyrhynchus) presenting for removal of a squamous cell carcinoma involving the third eyelid. Standing sedation was performed using initial boluses of medetomidine and butorphanol via intramuscular injection before catheter placement and maintenance with a variable rate infusion of medetomidine. Supraorbital, auriculopalpebral, infratrochlear blocks and local infiltration of the base of the third eyelid were performed using mepivacaine. Following the surgical removal of the third eyelid, atipamazole was administered intramuscularly to antagonize the effects of medetomidine. The patient recovered without complications. Conclusion: Medetomidine-butorphanol in combination with local anesthetic blocks provided a sufficient plane of sedation and analgesia for extra ocular surgery in a domesticated reindeer.

Morphological and histological study of the third eyelid in hedgehogs.

BACKGROUND: The third eyelid in animals plays an important role in maintaining eye health. Like other organs of the body, the third eyelid can be afflicted with minor or deep injuries, inflammations or even tumours in different species. OBJECTIVE: The current study investigates the morphological and histological characteristics of the third eyelid in hedgehogs. METHODS: Eight healthy adult hedgehogs (male and female) weighing 500-700 g were included in this study. Deceased animals were used for this study. Few incisions were applied around the eye and eye socket. The eye was removed, and the samples were fixated in 10% formalin solution to prepare for the histological study. To evaluate the morphological characteristics, the third eyelid was placed in 2% and 4% formalin solutions. RESULTS: The histological study revealed that the third eyelid cartilage is an elastic cartilage and includes chondroblasts and chondrocytes. The cells of this cartilage were either distributed individually or in isogenic groups. The bulbar and palpebral surfaces of the eyelids were devoid of any glands and were covered with a non-keratinized stratified squamous epithelium. The anatomical examination also showed that the third eyelid had an oval-shaped cartilage. CONCLUSIONS: Comparing the results of this study with reports on other rodents showed that the morphological and histological structure of the cartilage in the hedgehog's third eyelid is mostly like the structure of this tissue in Indian mongoose (Herpestes javanicus).

Subconjunctival enucleation with or without third eyelid removal may present a viable enucleation technique in rabbits: 18 cases (2014-2022).

OBJECTIVE: To evaluate intraoperative and postoperative complications and outcomes following subconjunctival enucleations with and without third eyelid removal in domestic rabbits. ANIMALS: 18 client-owned rabbits with ocular disease confined to the globe that underwent 20 subconjunctival enucleation procedures at a veterinary teaching hospital. METHODS: Records were retrospectively reviewed for all enucleations performed at a veterinary teaching hospital from 2014 to 2022. A standard subconjunctival enucleation procedure was performed in all cases, with third eyelid removal in 2 surgeries and without third eyelid removal in the remaining 18 surgeries. Outcomes were assessed on the basis of observations in medical records and owner follow-up. RESULTS: 20 total enucleations were included. Reported reasons for enucleation included suspected or confirmed ocular Encephalitozoon cuniculi infection in 9 rabbits, refractory glaucoma in 4 rabbits, and various intraocular diseases in 5 rabbits. The only intraoperative complication reported was hemorrhage during the third eyelid removal in 1 surgery. Postoperative complications included serous to mucoid discharge from the surgical site in 8 of 20 surgeries and swelling at the surgery site in 2 of the 8 cases that had discharge. Postoperative swelling spontaneously resolved within 3 months of surgery; postoperative discharge spontaneously resolved within 10 months of surgery. CLINICAL RELEVANCE: Subconjunctival enucleation with or without third eyelid removal in rabbits may be a viable enucleation technique to reduce the risk for intraoperative hemorrhage, but it can result in postoperative complications, including transient discharge and swelling at the surgical site.

Diminished pupillary light reflexes, elevated third eyelids, and decreased tear production are commonly associated with canine dysautonomia.

OBJECTIVE: To retrospectively describe ocular abnormalities reported in dogs with presumed dysautonomia. ANIMALS: 79 dogs with dysautonomia. METHODS: Medical records from the Kansas State University Veterinary Health Center from 2004 to 2021 were reviewed for dogs with a clinical or histopathologic diagnosis of canine dysautonomia (CD). Ophthalmic exam abnormalities, nonocular clinical signs, and outcomes were recorded. RESULTS: Most dogs (73/79 [92.4%]) with CD exhibited at least 1 ocular abnormality. The most common ocular abnormalities were diminished pupillary light reflexes (PLRs) in 55 of 79 (69.6%) dogs and elevation of the third eyelids in 51 of 79 (64.6%) dogs. Schirmer tear test values were bilaterally decreased in 32 of 56 (57.1%) dogs. Other ocular abnormalities included resting mydriasis, ocular discharge, photophobia, blepharospasm, corneal ulceration, and conjunctival vessel pallor. The most common nonocular clinical signs were vomiting or regurgitation in 69 of 79 (87.3%) and diarrhea in 34 of 79 (43.0%) dogs. Pharmacologic testing with dilute 0.01%, 0.05%, or 0.1% pilocarpine yielded pupillary constriction in 42 of 51 (82.4%) dogs. Thirty-two of 79 (40.5%) dogs survived to discharge. Resolution of ocular abnormalities was variable. CLINICAL RELEVANCE: Ophthalmic abnormalities such as diminished PLRs, elevation of the third eyelids, and decreased tear production are commonly associated with CD and provide support for its antemortem clinical diagnosis, though dogs with normal PLRs can be diagnosed with the disease. Pharmacologic testing with dilute topical pilocarpine in dogs with clinical signs suggestive of dysautonomia supports a diagnosis of CD. Ophthalmic abnormalities may improve or resolve over time.

Treatment of corneal ulceration and bullous keratopathy using a nictitating membrane flap in two horses.

OBJECTIVE: The aim of this study was to describe placement of a nictitating membrane flap as a treatment for corneal ulceration and bullous keratopathy in two horses. ANIMALS STUDIED: A 13-year-old American Saddlebred mare presented for severe corneal edema, superficial stromal ulceration, and a central bulla of the left eye. A 4-year-old Trakhener stallion also presented with a large axial bulla of the left eye with concurrent severe corneal edema and a deep stromal ulcer. PROCEDURE: A complete ophthalmic examination was performed. Samples were obtained for corneal cytology, and both horses were started on aggressive medical therapy. Both underwent general anesthesia for placement of a nictitating membrane flap and a subpalpebral lavage system (SPLS). RESULTS: Corneal cytology for each horse revealed a mixed bacterial population. Moderate Pseudomonas aeruginosa was cultured from the mare, while Aspergillus species and a few Enterococcus gallinarum were cultured from the stallion. The bullae in both horses resolved at 3 and 4 weeks and vision returned in the affected eye 4.5 and 3 months postoperatively at the last follow-up, respectively. CONCLUSION: Aggressive medical management with concurrent placement of a nictitating membrane flap is effective to treat bullous keratopathy in two horses. The described treatments could be used to treat horses that develop severe or progressive bullous corneal lesions.