A multicenter retrospective evaluation of the prevalence of known and presumed hereditary eye diseases in Lagotto Romagnolo dog breed within a referral population in Italy (2012-2020)

OBJECTIVE

To describe the ophthalmological findings of Lagotto Romagnolo dog breed and to report the prevalence of Known and Presumed Hereditary Eye Diseases (KP-HED).

ANIMALS STUDIED

Two hundred sixteen dogs were examined and included in this retrospective study.

PROCEDURES

Medical records of Lagotto Romagnolo dogs between 2012 and 2020 were included. Data about the ocular status were collected through ocular screening examinations (OSE) or clinical ophthalmic examinations (COE). The prevalence of each KP-HED was expressed as a function of the total number of the KP-HED in this referral population.

RESULTS

A total of 85 dogs (39.35%) were ophthalmologically healthy, ocular diseases presumably not hereditary were found in 43 dogs (19.91%), and 88 dogs (40.74%) were affected by one KP-HED. The most common KP-HEDs diagnosed were cataract (28/88; 31.82%), corneal endothelial dystrophy (17/88; 19.32%), retinal dysplasia (9/88; 10.23%), lens instability (7/88; 7.95%), progressive retinal atrophy (6/88, 6.82%), and keratoconjunctivitis sicca (6/88, 6.82%). Most of dogs with a KP-HED (77.27%, 68/88) were identified within COE group.

CONCLUSIONS

To the authors' knowledge, this is the first report of the prevalence of ocular disease in the Lagotto Romagnolo dog breed within a referral population in Italy. This study suggests a relatively high prevalence of KP-HED, with a characteristic late-onset presentation in some diseases. Many of these KP-HED's, lead to ocular pain and irreversible blindness, for this reason, the authors highlight the importance of aiming for an early diagnosis. Breeder's efforts and breeding programs should be directed at limiting such disorders.

The effects of soft cryotherapy on conjunctiva and cornea in isolated pig eyes and comparison with standard liquid nitrogen: A pilot ex vivo study

PURPOSE

To evaluate the immediate effects on cornea and conjunctiva of a cryosurgical method based on the application of a dimethyl ether, propane and isobutene solution (DMEPI, Histofreezer^® ), and of Liquid Nitrogen (LN₂ ; Cry-Ac Cryogun^® ).

METHODS

A total of 52 isolated pig eyes were obtained at the slaughterhouse, preserved for less than one hour in Ringer Lactate and divided into four groups. The first group included eyes treated with two applications of DMEPI in the center of the cornea, the second group eyes treated with DMEPI on the third eyelid's conjunctiva, the third group eyes treated with LN₂ on the third eyelid's conjunctiva and the fourth group included eyes treated with LN₂ on the central cornea. Each cryogen application (0.8 cm area) lasted 40 seconds. Each group included one (untreated) control eye. The eyes were submitted for routine histopathological evaluation. Histological alterations were recorded and scored with a semiquantitative scoring system.

RESULTS

No tissue alteration was detected on the conjunctiva, in any of the groups. Treated corneas showed mild to moderate cytoplasmic vacuolization of epithelial cells, shrinkage and hypereosinophilia of small groups of basal epithelial cells and stromal cleft formation.

CONCLUSIONS

Soft cryosurgery caused no severe acute histologically detectable damage to cornea and conjunctiva in isolated pig eyes, and no significant difference was observed when LN₂ and DMEPI treatments were compared. Further in vivo studies should be performed in order to verify possible delayed effects and the clinical efficacy of DMEPI cryosurgery in specific corneal and/or conjunctival diseases.

Use of four-layer porcine small intestinal submucosa alone as a scaffold for the treatment of deep corneal defects in dogs and cats: preliminary results

BACKGROUND

To describe the efficacy of four-layer porcine small intestinal submucosa (Vetrix BioSIS plus+) as single scaffold for the treatment of deep corneal lesions in dogs and cats.

METHODS

10 dogs and 3 cats with deep or full thickness corneal defects were treated surgically with BioSIS plus graft. Corneal transparency scores and vision were evaluated.

RESULTS

Lesions in dogs were four perforations, three descemetoceles, two limbal melanocytomas and one deep corneal ulcer. In cats, there were one limbal melanocytoma and two perforations. The average length of the follow-up was 86 days. In all, 12 out of 13 eyes treated were visual at last recheck (92.3 per cent). The scars were mild eight cases (66.7 per cent), but denser in four cases (33.4 per cent). Complication were partial collagenolysis in three cases (25 per cent), which resolved with medical therapy, mild corneal pigmentation in one case (8.4 per cent) and anterior synechia in one case (8.4 per cent). One case experienced severe collagenolysis and was enucleated 21 days postoperatively.

CONCLUSIONS

Four-layer porcine SIS graft was successfully used for surgical treatment of deep corneal lesions in selected corneal diseases in a small series of dogs and cats, with good results in terms of mechanic support and corneal transparency.

Bilateral orbital and nasal aspergillosis in a cat

A 12‐year‐old, 4 kg, castrated male Persian cat was referred with a 2‐month history of sneezing and bilateral mucopurulent nasal discharge. Rhinoscopically acquired nasal biopsies at this time revealed bilateral lymphoplasmacytic rhinitis. A tapering dose of oral prednisone caused the complete remission of the clinical signs, but 2 months after discontinuation of the therapy, the rhinitis recurred and the OD became exophthalmic. Computed tomography showed a soft tissue mass in both sides of the nasal cavity, both frontal sinuses, the right orbit, and to a lesser extent the left orbit. A fine needle aspirate of the right orbit revealed pyogranulomatous inflammation and Aspergillus spp. hyphae. Repeat nasal biopsy demonstrated multi‐focal necrosis and a mixed inflammatory cell process which now included macrophages and scattered septate fungal hyphae. A few days later the cat became bilaterally blind and a contrast enhancing lesion involving the optic chiasm was found on magnetic resonance imaging. Despite a poor prognosis, therapy consisted of exenteration of the right orbit and trephination of both frontal sinuses before the planned initiation of medical antifungal therapy. Unfortunately, the cat died of cardiac arrest intraoperatively. Aspergillus fumigatus was cultured from both orbits at necropsy. Orbital aspergillosis has been rarely reported in cats and its relationship with lymphoplasmacytic rhinitis is unclear. In this patient lymphoplasmacytic rhinitis or previous antibiotic/corticosteroid therapy may have allowed secondary fungal invasion of the nasal mucosa and subsequently both orbits and the brain. Alternatively, Aspergillus infection may have preceded the lymphoplasmacytic rhinitis.