Equine keratomycosis in the Netherlands from 2007 to 2017 28 cases : Voorjaarsdagen 2017 - Equine short communications (BEVA and Xcellent Horse Insurance Award)

EQUINE KERATOMYCOSIS IN THE NETHERLANDS FROM 2007 TO 2017 (28 CASES) Equine keratomycosis or fungal keratitis is a relatively common sight-threatening corneal disease in horses, particularly in warm, humid climates. Clinical manifestation includes corneal ulceration with or without corneal melting, microerosions, fungal plaque and stromal abscess. Aim of the study To determine clinical signs, diagnostic methods, predominant fungal isolates, treatment modalities and outcome of horses with keratomycosis in the Netherlands. Material and Methods Records of horses presented to the University of Utrecht, Equine Department suspected with keratomycosis between 2007 and 2017 were reviewed for this retrospective study. Information retrieved from the records included breed, ophthalmic examination findings, further diagnostics, treatment prior to and following presentation, and outcome. Results 28 Horses were suspected with keratomycosis by ophthalmic examination over a 10 year time period. No breed predilection was apparent. All horses had received either topical antibiotics or topical corticosteroids pre-referral. Ophthalmic examination showed corneal edema without ulceration (1/28), cornea ulceration (12/28; Fig 1.) or stromal abscess (15/28; Fig 2.). In 13 cases only a presumptive diagnosis was made by the ophthalmic findings of which 12/13 cases had a stromal abscess with an intact epithelium. In 15 cases keratomycosis was confirmed by fungal culture (13/15) and/or cytology (8/15). Aspergillus spp. was the most common isolate (92%). Treatment consisted of medication only (50%), medical combined with surgical treatment (32%), enucleation (11%) or euthanasia (7%). Miconazole was the topical antifungal medication utilized in all cases (100%). Globe retention was 88% (23/26). All cases that had follow-up available (12/26) developed corneal scarring (Fig 3). Conclusion Keratomycosis should be considered in horses presenting with keratitis (corneal edema, corneal ulceration and stromal abscess) in the Netherlands, with Aspergillus spp. being the most common isolate. It is a serious condition that commonly results in corneal ulceration and even corneal perforation, with loss of the globe. Definitive diagnosis of ulcerative keratomycosis depends on a positive fungal culture or identification of fungal hyphae on corneal cytology but is not always feasible due to the depth of the lesion (e.g. stromal abscess)

Equine keratomycosis in the Netherlands from 2007 to 2017 28 cases : Voorjaarsdagen 2017 - Equine short communications (BEVA and Xcellent Horse Insurance Award)

EQUINE KERATOMYCOSIS IN THE NETHERLANDS FROM 2007 TO 2017 (28 CASES) Equine keratomycosis or fungal keratitis is a relatively common sight-threatening corneal disease in horses, particularly in warm, humid climates. Clinical manifestation includes corneal ulceration with or without corneal melting, microerosions, fungal plaque and stromal abscess. Aim of the study To determine clinical signs, diagnostic methods, predominant fungal isolates, treatment modalities and outcome of horses with keratomycosis in the Netherlands. Material and Methods Records of horses presented to the University of Utrecht, Equine Department suspected with keratomycosis between 2007 and 2017 were reviewed for this retrospective study. Information retrieved from the records included breed, ophthalmic examination findings, further diagnostics, treatment prior to and following presentation, and outcome. Results 28 Horses were suspected with keratomycosis by ophthalmic examination over a 10 year time period. No breed predilection was apparent. All horses had received either topical antibiotics or topical corticosteroids pre-referral. Ophthalmic examination showed corneal edema without ulceration (1/28), cornea ulceration (12/28; Fig 1.) or stromal abscess (15/28; Fig 2.). In 13 cases only a presumptive diagnosis was made by the ophthalmic findings of which 12/13 cases had a stromal abscess with an intact epithelium. In 15 cases keratomycosis was confirmed by fungal culture (13/15) and/or cytology (8/15). Aspergillus spp. was the most common isolate (92%). Treatment consisted of medication only (50%), medical combined with surgical treatment (32%), enucleation (11%) or euthanasia (7%). Miconazole was the topical antifungal medication utilized in all cases (100%). Globe retention was 88% (23/26). All cases that had follow-up available (12/26) developed corneal scarring (Fig 3). Conclusion Keratomycosis should be considered in horses presenting with keratitis (corneal edema, corneal ulceration and stromal abscess) in the Netherlands, with Aspergillus spp. being the most common isolate. It is a serious condition that commonly results in corneal ulceration and even corneal perforation, with loss of the globe. Definitive diagnosis of ulcerative keratomycosis depends on a positive fungal culture or identification of fungal hyphae on corneal cytology but is not always feasible due to the depth of the lesion (e.g. stromal abscess)

Intraocular lens power calculation for the equine eye

Background Phacoemulsification and intraocular lens (IOL) implantation during cataract surgery in horses occur with increasing frequency. To reduce the postoperative refractive error it is necessary to determine the proper IOL power. In the present study retinoscopy, keratometry and ultrasonographic biometry were performed on 98 healthy equine eyes from 49 horses. The refractive state, corneal curvature (keratometry) and the axial location of all optical interfaces (biometry) were measured. The influences of breed, height at the withers, gender and age on values obtained and the comparison between the left and right eye were evaluated statistically. Corresponding IOL power were calculated by use of Binkhorst and Retzlaff theoretical formulas. Results Mean ± SD refractive state of the horses was + 0.32 ± 0.66 D. Averaged corneal curvature for Haflinger, Friesian, Pony, Shetland pony and Warmblood were 21.30 ± 0.56 D, 20.02 ± 0.60 D, 22.61 ± 1.76 D, 23.77 ± 0.94 D and 20.76 ± 0.88 D, respectively. The estimated postoperative anterior chamber depth (C) was calculated by the formula C = anterior chamber depth (ACD)/0.73. This formula was determined by a different research group. C and axial length of the globe averaged for Haflinger 9.30 ± 0.54 mm and 39.43 ± 1.26 mm, for Friesian 10.12 ± 0.33 mm and 42.23 ± 1.00 mm, for Pony 8.68 ± 0.78 mm and 38.85 ± 3.13 mm, for Shetland pony 8.71 ± 0.81 mm and 37.21 ± 1.50 mm and for Warmblood 9.39 ± 0.51 mm and 40.65 ± 1.30 mm. IOL power was calculated with the Binkhorst and Retzlaff theoretical formulas. Calculated IOL power for the several breeds ranged from 18.03 D to 19.55 D. The mean value across all horses was 18.73 D determined with Binkhorst formula and 18.54 D determined with Retzlaff formula. Conclusions Mean result of this study is: an 18.5 D IOL seemed to be the most appropriate to achieve emmetropia after IOL implantation in horses. Cataract surgery without IOL implantation results in hyperopic and visual compromised horses. Retinoscopy, keratometry and ultrasonographic biometry should be performed on every affected horse and postoperative visual outcome should be determined

Intraocular lens power calculation for the equine eye

Background Phacoemulsification and intraocular lens (IOL) implantation during cataract surgery in horses occur with increasing frequency. To reduce the postoperative refractive error it is necessary to determine the proper IOL power. In the present study retinoscopy, keratometry and ultrasonographic biometry were performed on 98 healthy equine eyes from 49 horses. The refractive state, corneal curvature (keratometry) and the axial location of all optical interfaces (biometry) were measured. The influences of breed, height at the withers, gender and age on values obtained and the comparison between the left and right eye were evaluated statistically. Corresponding IOL power were calculated by use of Binkhorst and Retzlaff theoretical formulas. Results Mean ± SD refractive state of the horses was + 0.32 ± 0.66 D. Averaged corneal curvature for Haflinger, Friesian, Pony, Shetland pony and Warmblood were 21.30 ± 0.56 D, 20.02 ± 0.60 D, 22.61 ± 1.76 D, 23.77 ± 0.94 D and 20.76 ± 0.88 D, respectively. The estimated postoperative anterior chamber depth (C) was calculated by the formula C = anterior chamber depth (ACD)/0.73. This formula was determined by a different research group. C and axial length of the globe averaged for Haflinger 9.30 ± 0.54 mm and 39.43 ± 1.26 mm, for Friesian 10.12 ± 0.33 mm and 42.23 ± 1.00 mm, for Pony 8.68 ± 0.78 mm and 38.85 ± 3.13 mm, for Shetland pony 8.71 ± 0.81 mm and 37.21 ± 1.50 mm and for Warmblood 9.39 ± 0.51 mm and 40.65 ± 1.30 mm. IOL power was calculated with the Binkhorst and Retzlaff theoretical formulas. Calculated IOL power for the several breeds ranged from 18.03 D to 19.55 D. The mean value across all horses was 18.73 D determined with Binkhorst formula and 18.54 D determined with Retzlaff formula. Conclusions Mean result of this study is: an 18.5 D IOL seemed to be the most appropriate to achieve emmetropia after IOL implantation in horses. Cataract surgery without IOL implantation results in hyperopic and visual compromised horses. Retinoscopy, keratometry and ultrasonographic biometry should be performed on every affected horse and postoperative visual outcome should be determined

Distichiasis in a ferret (Mustela putorius furo)

A 4-year-old intact male ferret was presented to the Ophthalmology Service of the Department of Clinical Sciences of Companion Animals of Utrecht University with chronic blepharospasm, epiphora, and conjunctivitis of the right eye. Examination of the eye revealed mild conjunctivitis and three hairs protruding from the openings of meibomian glands in the upper eyelid, providing the clinical diagnosis of distichiasis. The distichia were removed by transconjunctival unipolar electrocautery. Recovery was uneventful, but the original signs recurred 10 weeks after surgery. Ophthalmic examination revealed another distichia at a different location in the same eyelid and it was removed by full-thickness wedge excision. Histopathological examination failed to reveal the exact origin of the distichia. To our knowledge, this is the first reported case of distichiasis in a ferret

Evaluation of the oral fludrocortisone suppression test for diagnosing primary hyperaldosteronism in cats

Background: Primary hyperaldosteronism (PHA) in cats is suggested by clinical signs and an elevated plasma aldosterone- to-renin ratio (ARR), but a test to confirm the diagnosis is lacking. Hypothesis: Fludrocortisone does not suppress urinary aldosterone excretion in cats with PHA, but does so in cats with arterial hypertension because of other causes. Animals: Nineteen client-owned cats with arterial hypertension because of PHA (n = 9) or other causes (n = 10). Methods: Prospective clinical study. The urinary aldosterone-to-creatinine ratio (UACR) was determined in morning urine before, during, and after 4 days of oral fludrocortisone administration in a dose of 0.05 mg/kg q12h. Arterial blood pressure and plasma potassium concentration were measured before and after fludrocortisone administration. Results: A basal UACR above 46.5 9 10 9, the upper limit of the reference range, was found in 3 cats with PHA. All PHA cats had basal UACRs >7.5 9 10 9. In all non-PHA cats with a basal UACR >7.5 9 10 9, fludrocortisone administration induced >50% suppression. In contrast, fludrocortisone administration resulted i