A Retrospective study on the association between vitreous degeneration and cataract in dogs

A Post-Operative Follow-Up of an Endangered Saltwater Fish Lensectomy for Cataract Management in a Public Aquarium: A Case Series

Mature cataracts can be a life-threatening condition in fish as it may result in anorexia. Lens extraction has been previously described in fish, but the long-term outcome of this procedure has not been evaluated. Eleven captive-bred adult fish housed in a public aquarium presented with unilateral (n = 3/11) or bilateral (n = 8/11) mature cataracts. All cases belonged to three endangered fish populations: striped bass (Morone saxatilis) originating from the Saint Lawrence River and Atlantic and spotted wolffish (Anarhichas lupus and Anarhichas minor). Pre-operatively, fish presented with anorexia, dark discoloration, abnormal position in the water column, skin abrasions, and/or decreased body condition scores. A lensectomy was performed in eleven fish, including a bilateral procedure in four fish, corresponding to fifteen eyes. Follow-up examinations were performed one to two weeks and one year post surgery. The main complication was self-resolving: corneal edema was present in 67% of eyes, persistent after a week in 47% of eyes, and resolved thereafter. Post-operatively, 73% of fish resumed feeding and regained a good body condition score. Persistent visual impairment post-surgery associated with anorexia required euthanasia in three out of eleven cases. The median time of death was 336 days post surgery (range: 27-1439 days) and three cases were still alive 1334 to 1425 days after the lensectomy. This was considered a favorable outcome for these older individuals with concurrent diseases.

Long-term evaluation of the effects of vitreous degeneration on cataracts and retinal detachment in dogs

OBJECTIVE

We aimed to track and evaluate the association between vitreous degeneration and the development of cataracts or retinal detachments in dogs over a long period.

ANIMAL STUDIED

Data on vitreous degeneration, cataracts, and retinal detachment in 102 eyes were collected from 68 dogs who underwent ocular ultrasonography at least twice between March 2017 and November 2021 at the Veterinary Medical Teaching Hospital, Konkuk University. The mean follow-up time was 515 ± 256 (mean ± standard deviation; range: 81-1196) days.

PROCEDURE

Development of cataracts and retinal detachment, according to the severity of vitreous degeneration grade (VDG), was evaluated during long-term follow-up.

RESULTS

In the cataract study (87 eyes, 61 dogs), the number of cataracts developed according to VDG (grade: 0-3) were as follows: VDG 0: 1 in 10 (10%) eyes, VDG 1: 15 in 35 (43%) eyes, VDG 2: 15 in 30 (50%) eyes, and VDG 3: 10 in 12 (83%) eyes. It was significantly different among grades (p = .026). In the retinal detachment study (95 eyes, 64 dogs), the number of retinal detachments developed according to each VDG were as follows: VDG 0: 0 in 11 (0%) eyes, VDG 1: 1 in 36 (3%) eyes, VDG 2: 5 in 35 (14%) eyes, and VDG 3: 4 in 13 (30%) eyes. It was also significantly different among grades (p = .019).

CONCLUSIONS

During long-term follow-up, dogs with severe vitreous degeneration had an increased risk of cataract and retinal detachment development than those without or with mild vitreous degeneration.

Evaluation of vitreous degeneration as a potential risk factor for retinal detachment after phacoemulsification in dogs

PURPOSE

To evaluate vitreous degeneration as a potential risk factor for retinal detachment in dogs after phacoemulsification.

METHODS

Medical records for dogs with preoperative ocular ultrasound and phacoemulsification between September 28, 2006, and August 2, 2016, were reviewed. Ultrasound images were reviewed by two observers independently, and vitreous echogenicity was graded using an established scale. The following factors were compared between eyes with and without retinal detachment: signalment, operated eye, cataract stage at the time of surgery, and presence or absence of the following: lens-induced uveitis (LIU), glaucoma, anterior vitreous presentation, lens subluxation, history of prophylactic retinopexy, diabetes mellitus, operating surgeon, concurrent prophylactic retinopexy, posterior capsular tear, phacoemulsification duration, use of automated anterior vitrectomy, placement of an artificial intraocular lens, and intraocular lens type (polymethyl methacrylate or acrylic foldable). Total follow-up time was recorded. Presence and time from surgery to onset of complications were recorded. Retinal detachment was diagnosed based on observation via indirect ophthalmoscopy or ocular ultrasound.

RESULTS

Evaluation for association between vitreous degeneration and retinal detachment included 290 eyes of 180 dogs. There was no statistically significant correlation between vitreous degeneration and postoperative retinal detachment. Retinal detachment was observed in 17 of 290 eyes (5.9%). Vitreous degeneration was marked as present by at least one observer in 189 of 290 eyes (65%).

CONCLUSIONS

Ultrasonically identifiable vitreous degeneration does not correlate with increased risk of retinal detachment following phacoemulsification.

Vitreous degeneration and associated ocular abnormalities in the dog

OBJECTIVE

To identify the frequency of vitreous degeneration and its association with ocular comorbidities including cataracts, lens luxation, glaucoma, and retinal detachment.

METHODS

This is a retrospective study of 4217 dogs from the Companion Animal Eye Registry (CAER) that underwent breed screening ophthalmic examinations between 2013 and 2016. The breeds analyzed included the Italian Greyhound, Shih Tzu, Affenpinscher, Bichon Frise, Brussels Griffon, Whippets, and Greyhound. Data collected from CAER included age, gender, number of examinations, and whether vitreous degeneration, along with cataracts, lens luxation, glaucoma and/or retinal detachment were present in either or both eyes.

RESULTS

The study found that breed and age are significant drivers for developing VD. Italian Greyhounds, Brussels Griffons, and Shih Tzus have a significantly higher likelihood of VD compared to the negative control breed, the Greyhound. Additionally, with every 1-year age increase, there is a 24% higher likelihood of developing VD. However, no association was identified between vitreous degeneration and cataracts, lens luxation, glaucoma, or retinal detachment.

CONCLUSIONS

While the study found that breed and age were significant drivers for developing VD, no association was found between VD and the other ocular comorbidities examined.

Epidemiology of ocular disorders presumed to be inherited in three small Italian dog breeds in Italy

OBJECTIVE

To describe the prevalence and the types of eye disorders that are known or presumed to be inherited (KP-HED) in three small Italian dog breeds.

ANIMALS

Three small Italian dog breeds: Maltese, Bolognese, and Italian Greyhound.

PROCEDURES

All dogs of the breeds selected for this prospective observational study that underwent a complete ophthalmic examination between 1994 and 2015 were included. General and proportional KP-HED prevalence with 95% confidence intervals were reported.

RESULTS

Three hundred and six of 462 dogs were affected by at least one KP-HED (66.2%; 95% CI: 61.8%-70.4%). In the entire population, the five most common KP-HED were cataract (n = 122; rate on the total number of KP-HED: 31.4%), entropion (n = 56; 14.4%), keratoconjunctivitis sicca (n = 33; 8.5%), retinal dysplasia (n = 24; 6.2%), and persistent pupillary membrane (iris to iris) (n = 21; 5.4%). The most common KP-HED in each breed were cataracts in the Maltese (35.1%) and in the Bolognese (24.2%), and presentation of vitreous in the anterior chamber in the Italian Greyhound (46.7%).

CONCLUSIONS

Clinicians should be aware of KP-HED that commonly affect three small Italian dog breeds. Breed standards should be reconsidered, and breeding programs should be directed at limiting such disorders.

Retinal detachment postphacoemulsification in Bichon Frises: a retrospective study of 54 dogs

OBJECTIVE

To compare rates of retinal detachment (RD) postphacoemulsification in American Bichon Frises with and without prophylactic retinopexy.

PROCEDURES

Medical records of 54 Bichon Frises undergoing phacoemulsification with or without prophylactic retinopexy between 2003 and 2013 in one or both eyes were reviewed from five Midwestern university veterinary teaching hospitals. Inclusion criteria were preoperative ERG, at least 6 months of follow-up postphacoemulsification, and the absence of preexisting RD as determined by ophthalmic examination and/or ultrasound. Statistical analyses were performed using chi-squared test, and Wilcoxon rank-sum tests and Wilson confidence intervals with the P-value <0.05 were considered significant.

RESULTS

Phacoemulsification was performed without retinopexy in 79 eyes (42 dogs, non-PR group) and with prophylactic retinopexy in 23 eyes (12 dogs, PR group). Incidence of diabetes mellitus was 10/42 and 3/12 in the non-PR and the PR groups, respectively (P = 0.93). Intraocular lens implantation was performed in 40/42 non-PR dogs and 11/12 PR dogs (P = 0.63, 73/79 vs. 21/23 eyes). At final re-examination, RD occurred in 4/79 eyes without retinopexy, compared to 0/23 RD in the retinopexy group. There was no statistically significant difference in RD rates between the two groups (P = 0.27).

CONCLUSIONS

These data provide no statistical evidence to support prophylactic retinopexy in Bichon Frises. Due to the low rate of retinal detachment following phacoemulsification without prophylactic retinopexy, the procedure appears to offer limited benefit to offset cost, procedural risk, and risk of extended or repeated anesthesia in Bichon Frises.