Corneal epithelial inclusion cyst in the dog

Unilateral corneal epithelial inclusion cysts are recorded in a series of 16 dogs. The cysts were not congenital, there was no breed incidence, and in 11 patients there was history of corneal trauma or ulceration before cyst formation. There was some variability in clinical presentation, and sight was affected in six dogs. Fifteen patients were treated successfully by superficial keratectomy without cyst recurrence.     

Corneal epithelial inclusion cyst in a Llama

A 13-year-old, female Llama presented for evaluation of a limbal based corneal mass involving the OD of 4 months duration. The mass was excised en bloc by a nonpenetrating keratectomy, followed by placement of a conjunctival advancement flap covering the keratectomy site. The mass was submitted for histological evaluation. Histopathology identified the mass to be a corneal epithelial inclusion cyst filled with necrotic squamous and neutrophilic debris. Surgical excision was complete and considered curative with no signs of recurrence 3 months postoperatively. There was no known prior ocular trauma; however, a previously performed corneal biopsy for evaluation of recurrent epithelial erosions may have been an initiating cause.     

A case of multiple unilateral corneal epithelial inclusion cysts in a dog

A three-year-old neutered female Labrador cross was presented for investigation of two corneal epithelial inclusion cysts affecting the left eye. The aetiopathogenesis of the cyst formation was suspected to be traumatic. The cysts were removed successfully by superficial keratectomy, followed by a third eyelid flap. Histologically, both lesions were represented by cystic formations lined with multi-layered squamous epithelium, consistent with stromal inclusion of surface corneal epithelium. Complete recovery was achieved, and there was no recurrence at six month follow-up.     

Primary central corneal hemangiosarcoma in a dog

Purpose To report a case of primary central corneal hemangiosarcoma in the dog. Methods An 11‐year‐old, neutered, female, German shepherd mixed breed dog was referred to the Hospital Veterinario Sierra de Madrid (Spain) for evaluation of an enlarging corneal mass of the left eye (OS). The dog was predominantly housed outdoors and was diagnosed with a history of chronic superficial keratitis of both eyes (OU) by the referring veterinarian. The corneal mass was resected by routine superficial keratectomy and submitted for histopathology and Factor VIII immunohistochemical staining. Results The mass was diagnosed as a corneal hemangiosarcoma with complete excision. Postoperatively, the keratectomy site healed without complication and there was no evidence of recurrence three and a half months postoperatively. Complete systemic evaluation, including abdominal ultrasound and CT scan of the head and thorax, indicated no other detectable neoplasia in the dog. Discussion Outdoor housing and ultraviolet exposure, breed, and chronic superficial keratitis were all suspected as contributing factors to the development of a primary corneal hemangiosarcoma. Surgical removal and postoperative treatment for chronic superficial keratitis provided effective therapy.     

Superficial, nonhealing corneal ulcers in horses: 23 cases (1989-2003)

Objective To characterize superficial, nonhealing corneal ulcers in the horse and to assess the affect of age, breed, sex, inciting cause of the ulcer, and treatment on healing time of these ulcers. Design Retrospective study. Animals Twenty‐three horses with superficial, nonhealing corneal ulcerations. Procedure Medical records from 1989 to 2003 of horses diagnosed with superficial, nonhealing corneal ulcers were reviewed. Signalment, duration of clinical signs, ophthalmic abnormalities, treatment and response to treatment were recorded. Horses were treated, in addition to medical therapy, using debridement, debridement and grid keratotomy, superficial keratectomy, and superficial keratectomy with conjunctival graft placement. Results Mean age ± SD of horses was 13.7 ± 5.8 years. The mean time of presence of the corneal ulceration was 38.9 ± 21.3 days. Mean time to complete re‐epithelialization of the corneal ulcers after treatment was 20 ± 14.7 days. Horses treated with debridement alone, grid keratotomy and superficial keratectomy healed in a mean time of 15.3 ± 14.6 days, 16 ± 12.6 days, and 22.8 ± 6.7 days, respectively. Conclusions and clinical relevance Horses treated with a single debridement at initial evaluation healed in a significantly shorter time period than horses treated with grid keratotomy or superficial keratectomy. The latter two procedures may be beneficial in the treatment of nonhealing ulceration in horses, but the results of this study suggest that these procedures should only be performed following failure of the ulcer to heal after epithelial debridement.     

Corneal squamous cell carcinoma in two dogs

Purpose To report two cases of corneal squamous cell carcinoma (SCC) in dogs. Methods Corneal tumors were resected by superficial keratectomy in two cases. Immunohistochemistry of the corneal tissues was performed using anti‐p53 antibody. Results The prominent features of the cases were a clinical history of pigmentary keratitis and chronic keratitis. In each case, a corneal mass was surgically removed with a superficial keratectomy and histologically diagnosed as corneal SCC. Both masses were negative for p53. To reduce chronic corneal irritation, 0.1% hyaluronate sodium ophthalmic solution was applied. After more than 15 months of postsurgical follow‐up there has been no recurrence of either neoplasm. Conclusion and discussion Chronic corneal irritation was suspected as the primary etiology for the corneal SCC. Appropriate surgical removal of the mass and subsequent conservative treatment for keratitis provided effective therapy in these two cases.     

Primary corneal melanocytoma in a Collie

A 6‐year‐old female, spayed Collie was referred to the Western College of Veterinary Medicine for a 12‐month history of a progressive right corneal mass. A superficial keratectomy was performed and histopathology revealed a corneal melanocytoma with complete excision. There has been no recurrence of the neoplasm to date (12 months). This is the first known report of an isolated corneal melanocytoma in a canine.     

CASE REPORT: Corneal papilloma associated with papillomavirus in a one‐humped camel (Camelus dromedarius)

A 15‐year‐old male dromedary camel with a history of chronic severe keratoconjunctivitis and corneal mass in the left eye of 6 months’ duration was referred to the Veterinary Medical Teaching Hospital at Adnan Menderes University. A superficial keratectomy was performed and biopsy material submitted for histopathology. The diagnosis was corneal papilloma. There has been no recurrence of the neoplasm to date (6 months, 1 year). Corneal papilloma has not been reported previously in camels and seems to be associated with papillomavirus.     

Thermal cautery of the cornea for treatment of spontaneous chronic corneal epithelial defects in dogs and horses

A thermal cautery technique was used to treat spontaneous chronic corneal epithelial defects (SCCEDs) in 9 eyes of 8 dogs and 2 eyes of 2 horses. Animals were sedated, and a topical anesthetic was applied. A handheld thermal cautery unit was then used to make multiple, small (< or = 1 mm in diameter), superficial burns throughout the affected area. The cautery unit was applied just until the slightest degree of contraction of the collagen fibrils was observed. After the stromal bed of the defect was treated, a rim of epithelium that extended approximately 1 mm around the denuded stroma was also subjected to thermal cautery. Following surgery, a contact lens was placed in dogs but not in horses, and the eye was treated with broad-spectrum antimicrobial ophthalmic solutions. Defects in all 11 eyes healed with minimal scarring; mean time to healing in dogs was 2.1 weeks (range, 2 to 3 weeks). The defect healed in 1 week in 1 horse and in 2 weeks in the other. Many therapeutic options are available for the treatment of SCCEDs. Procedures such as epithelial debridement and anterior stromal puncture have been shown to have a high rate of success. In cases for which these less invasive procedures fail, our results suggest that thermal cautery may be a reasonable alternative to previously described treatments for SCCEDs in dogs and horses prior to more invasive procedures such as superficial keratectomy.     

Amniotic membrane transplantation for corneal surface reconstruction after excision of corneolimbal squamous cell carcinomas in nine horses

OBJECTIVE: The purpose of this study was to evaluate the usefulness and effectiveness of permanent amniotic membrane transplantation as an adjunctive treatment to superficial keratectomy alone or combined with strontium-90 irradiation for treatment of equine corneolimbal squamous cell carcinoma (SCC) to decrease corneal scarring and recurrence rate. STUDY: The retrospective case study included 11 horses (n = 12 eyes) diagnosed and treated for ocular SCC that involved the limbus and cornea. Nine of those horses (n = 9 eyes) were treated between 2002 and 2006, with superficial lamellar keratectomy alone or combined with strontium-90 irradiation and followed by placement of a permanent amniotic membrane graft in the surgical defect. The level of scarring (i.e. the clarity of the cornea) resulting with the use of amniotic membrane was subjectively compared to cases where a permanent bulbar conjunctival graft was performed following keratectomy combined with strontium-90 irradiation or cryotherapy (n = 3 eyes). Recurrence was defined as the postoperative and postirradiation regrowth of SCC in the same site and globe. RESULTS: The nine horses that received an amniotic membrane graft after keratectomy alone or combined with irradiation showed a minimal level of scarring in a cornea that regained a greater transparency in comparison to the horses that were treated with a bulbar conjunctival graft. All of the horses that received an amniotic membrane graft had 226 +/- 218 days of follow-up without tumor recurrence (mean +/- SD), ranging from 21 days to 778 days. CONCLUSIONS: The combination of superficial keratectomy alone or associated with beta-irradiation and permanent amniotic membrane transplantation is an effective treatment of corneal or corneolimbal SCC in horses. The placement of an amniotic membrane material represents an alternative surgical procedure to bulbar conjunctival grafts, especially if there is a lack of bulbar conjunctiva tissue available after tumor resection or if a particularly large corneal resection is necessary. The amniotic membrane is incorporated into the corneal defect and seems to create noticeably much less scarring than a corneal defect covered by bulbar conjunctiva.     

Spontaneous chronic corneal epithelial defects in dogs: a review

Spontaneous chronic corneal epithelial defects (SCCEDs) in dogs are typically found in middle-aged dogs of all breeds. These epithelial defects may be present for weeks to months, particularly if left untreated or if treated inappropriately. Typical histopathological findings include loss of the corneal epithelial basement membrane and formation of a superficial, acellular, hyalinized zone in the stroma. Together, these histological abnormalities lead to delayed wound healing and poor epithelial adhesion. Epithelial debridement, anterior stromal puncture, grid keratotomy, and superficial keratectomy are the most common treatment options applied to the defects. Procedures that address the stromal changes present generally have a higher success rate than epithelial debridement alone.     

Diagnosis and management of chronic corneal epithelial defects (indolent corneal ulcerations)

Chronic corneal epithelial defects (CCEDs; indolent corneal ulcerations) are the most common refractory ulcerations in veterinary medicine and are diagnosed by their classic appearance. CCEDs are superficial ulcerations without stromal involvement and have a nonadherent epithelial border (lip). Fluorescein stain adheres to the exposed stroma and extends below the epithelial border, outlining the epithelial lip. CCEDs occur secondary to adnexal disease, keratoconjunctivitis sicca, exposure keratitis, neurotrophic keratitis, and primary corneal disease. In cats, herpes keratitis is associated with the development of CCEDs. Bacterial infections are not responsible for the refractory nature of CCEDs. Because of the refractory nature of CCEDs, treatment can be frustrating for both owner and veterinarian. Current treatment recommendations consist of identifying and treating the underlying cause and performing procedures that stimulate epithelialization and adhesion of the corneal epithelium. Initial treatment of CCEDs includes ulcer debridement and grid keratotomy. Superficial keratectomy is indicated in refractory cases.     

Microsporidial keratopathy in two dogs

A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.     

一例法斗犬眼角膜皮样囊肿切除及结膜瓣遮盖术

角膜皮样囊肿是一种长在人或动物的角膜、结膜、角巩膜等处被覆毛发的异常皮肤样组织。在人和动物均可见,动物中尤其是在牛和犬中较为常见。角膜皮样囊肿可以引发眼睑痉挛、眼分泌物增加、结膜炎、角膜炎和角膜溃疡等,严重者可导致角膜穿孔和眼球坏死。通过角膜切除术或结膜切除术,切除角膜皮样囊肿并对症治疗的方法来治疗眼部角膜皮样囊肿。以下是在2022年3月接诊的一例幼年法斗犬患有右侧眼角膜皮样囊肿,对患犬实施浅层角膜切除术切除右侧角膜皮样囊肿并用结膜瓣遮盖的手术方法进行治疗,术后恢复良好。     

Conjunctival dermoid in two guinea pigs: a case report

Clinical and histologic findings of conjunctival dermoids in two unrelated guinea pigs are described. The dermoids were treated surgically by resection with superficial lamellar keratectomy and corneal epithelial debridement. Histologically the dermis underneath a stratified squamous keratinized and variably pigmented epithelium consisted of multiple hair follicles, with clearly visible arrectores pilorum muscles, sebaceous glands and loose vascularized fatty tissue.     

Keratoconjunctivitis associated with Toxoplasma gondii in a dog

A 12-year-old Pug presented with a 3-mm corneal mass OD. The dog was currently being treated for keratoconjunctivitis sicca (KCS) and pigmentary keratitis OU. A superficial keratectomy followed by cryotherapy was performed OD. A histopathologic diagnosis of epithelial dysplasia and suppurative keratitis was made and the lesion resolved. Two months later, a yellow/tan conjunctival mass, diffuse chemosis and conjunctival thickening was discovered OD. Necrotizing conjunctivitis with protozoal parasites was diagnosed with histopathology. Complete blood count and a serum biochemistry panel were normal. Neospora caninum and Toxoplasma gondii titers were negative. The conjunctivitis resolved after a 6-week course of oral clindamycin. Two months later, the patient presented with a similar conjunctival mass OS. Toxoplasma gondii was confirmed as the etiologic agent with immunohistochemical staining. Repeat T. gondii titers were negative. Oral clindamycin was re-instituted. The corneal biopsy was re-reviewed and protozoal organisms were discovered. Three months later, a recurrence was suspected and oral ponazuril was initiated for 28 days. There has been no evidence of recurrence since this treatment. Ocular toxoplasmosis is rare in the dog but reports have included episcleritis, scleritis, retinitis, anterior uveitis, ciliary epithelium hyperplasia, optic neuritis and polymyositis. To our knowledge, this is the first confirmed report of toxoplasmosis causing only corneal and conjunctival disease in the dog. We hypothesize that these localized lesions may be associated with topical immunomodulating therapy for KCS. Toxoplasmosis should be considered as a differential for canine conjunctivitis and corneal disease and has the potential to manifest in one or both eyes.     

Nonhealing corneal ulcers in cats: 29 cases (1991-1999)

OBJECTIVE: To compare mean healing times after debridement, debridement with grid keratotomy, and superficial keratectomy in cats with nonhealing corneal ulcers. DESIGN: Retrospective study. ANIMALS: 29 cats with 36 nonhealing corneal ulcers. PROCEDURE: Medical records of cats with nonhealing corneal ulcers were reviewed. Signalment, duration of clinical signs, ophthalmic abnormalities, and response to various treatment protocols were recorded. RESULTS: Mean age of affected cats was 7 years, 8 months. Affected breeds included domestic shorthair (17 cats), Persian (9), Himalayan (2), and Siamese (1). Clinical signs were evident for approximately 2 weeks prior to referral. Both eyes were affected in 4 cats. Mean healing time of ulcers treated with superficial debridement was 30 days. Mean healing time of ulcers treated with superficial debridement and grid keratotomy was 42 days. Superficial keratectomy was performed on 2 eyes and resulted in a healing time of 2 weeks. Formation of a corneal sequestrum was evident in 2 of 21 eyes treated with superficial debridement. Formation of a corneal sequestrum was evident in 4 of 13 eyes treated with superficial debridement and grid keratotomy. CONCLUSIONS AND CLINICAL RELEVANCE: Brachycephalic cats appear to be predisposed to developing nonhealing corneal ulcers. The combination of superficial debridement and grid keratotomy did not decrease mean healing time of nonhealing ulcers, compared with superficial debridement alone. Grid keratotomy may predispose cats with corneal ulcers to develop a corneal sequestrum.     

Carbon dioxide laser photoablation adjunctive therapy following superficial lamellar keratectomy and bulbar conjunctivectomy for the treatment of corneolimbal squamous cell carcinoma in horses: a review of 24 cases

Objective To determine the complications and nonrecurrence rates following superficial lamellar keratectomy, bulbar conjunctivectomy, and adjunctive carbon dioxide (CO₂) photoablation for corneolimbal squamous cell carcinoma (SCC) in the horse. Study design Retrospective study. Sample population Twenty‐four horses with corneolimbal SCC. Procedure Medical records of horses diagnosed with corneolimbal SCC that was surgically excised and where CO₂ photoablation was used as an adjunctive therapy from 2000 to 2007 were reviewed. Signalment, prior therapy, tumor location and size, complications, and recurrence of SCC were recorded. Results The Thoroughbred was the most commonly (25%) represented breed. Lesions were >10 mm in diameter in 70.8% of cases. Eight horses (33.3%) had neoplastic cells extending to the deep margin of the keratectomy. All horses were available for follow‐up for an average ± standard deviation of 40.7 ± 25 months. Four horses (16.7%) developed a recurrence of SCC. Three of these four horses underwent repeat keratectomy and CO₂ photoablation, one each, at 4 months, 1, and 2 years following the initial procedure. One horse underwent enucleation 8 months following the initial procedure. Conclusions and clinical relevance As an adjunctive therapy, CO₂ photoablation was successful in 87.5% of the horses following a single procedure and in a total of 91.7% following a second therapeutic application. CO₂ photoablation appears to be effective as an adjunctive therapy following removal of large corneolimbal SCC in the horse and in cases in which all tumor cells were not excised.     

Canine amniotic membrane transplantation for corneal reconstruction after the excision of dermoids in dogs

Transplantation of canine amniotic membrane (AM) in conjunction with a third eyelid flap was performed after the removal of large dermoids by keratectomy and conjunctivectomy on 7 eyes of 7 dogs. Corneal epithelialization was completed within 2 weeks after the transplantation. Five eyes attained normal transparency of the cornea within 5 weeks. Slight pigmentation of the bulbar conjunctiva at the limbus was observed in 1 dog that had pre-existing pigmentary keratitis. Neovascularization and scarring of the cornea and impaired vision were not found in any dogs at 8 weeks after the transplantation. In conclusion, transplantation of canine AM can promote corneal healing after the excision of large dermoids in dogs.