To describe a novel scoring system of feline pigmented iris lesions prior to utilization of diode laser ablation of progressive pigmented iris lesions and to retrospectively evaluate short- and long-term patient outcomes following transcorneal diode laser ablation.
317 client-owned cats (356 eyes) were included.
Records of cats undergoing diode laser ablation from January 2000 to December 2018 were retrospectively reviewed. A novel clinical grading system to describe severity of feline iris hyperpigmentation was developed. Recorded parameters included signalment, operated-upon eye, presurgical iris pigmentation score, intraocular pressure, visual status, postoperative complications, repeat laser surgery, patient status at last follow-up, time to death, and presumptive or known cause of death.
Complications included corneal ulceration (25/356 [7%]), glaucoma (18/356 [5%]), uveitis (4/356 [1.1%]), and corneal edema (3/356 [0.8%]). Enucleation was performed in 12 eyes due to blindness and secondary glaucoma. Repeat laser due to continued progression of pigment was performed in 18.5% of eyes. Two study patients were euthanized due to presumptive metastatic disease. Of the 250 cats for whom confirmation was available via phone call or medical records, 240 (96%) were alive at 1 year.
Diode laser ablation appears safe overall and may be effective in decreasing progression of feline iris pigmentation. Complication risks appear minimal.
Objective—To evaluate expression of cyclooxygenase (COX)-1 and COX-2 in the cornea, eyelid, and third eyelid of healthy horses and those affected with squamous cell carcinoma (SCC) by use of immunohistochemical techniques.
Animals—15 horses with SCC involving ocular tissues and 5 unaffected control horses.
Procedures—SCC-affected tissues were obtained from the cornea (n = 5 horses), eyelid (5), and third eyelid (5). Site-matched control tissues were obtained from 5 horses unaffected with SCC. Tissue sections of affected and control cornea, eyelid, and third eyelid were stained immunohistochemically for COX-1 and COX-2 via standard techniques. Stain uptake was quantified by use of computer-assisted image analysis of digital photomicrographs.
Results—Immunoreactivity for both COX-1 and COX-2 was significantly greater in equine corneas with SCC than in control corneas. No significant differences in COX-1 or COX-2 immunoreactivity were detected in eyelid and third-eyelid SCC, compared with site-matched control tissues.
Conclusions and Clinical Relevance—Immunoreactivity for COX-1 and COX-2 is high in equine corneal SCC, possibly indicating that COX plays a role in oncogenesis or progression of this tumor type at this site. Pharmacologic inhibition of COX may represent a useful adjunctive treatment for corneal SCC in horses.
OBJECTIVE To evaluate the coding regions of ADAMTS17 for potential mutations in Chinese Shar-Pei with a diagnosis of primary open-angle glaucoma (POAG), primary lens luxation (PLL), or both.
ANIMALS 63 Shar-Pei and 96 dogs of other breeds.
PROCEDURESADAMTS17 exon resequencing was performed on buccal mucosal DNA from 10 Shar-Pei with a diagnosis of POAG, PLL, or both (affected dogs). A candidate causal variant sequence was identified, and additional dogs (53 Shar-Pei [11 affected and 42 unaffected] and 95 dogs of other breeds) were genotyped for the variant sequence by amplified fragment length polymorphism analysis. Total RNA was extracted from ocular tissues of 1 affected Shar-Pei and 1 ophthalmologically normal Golden Retriever; ADAMTS17 cDNA was reverse transcribed and sequenced, and ADAMTS17 expression was evaluated by quantitative reverse-transcription PCR assay.
RESULTS All affected Shar-Pei were homozygous for a 6-bp deletion in exon 22 of ADAMTS17 predicted to affect the resultant protein. All unaffected Shar-Pei were heterozygous or homozygous for the wild-type allele. The variant sequence was significantly associated with affected status (diagnosis of POAG, PLL, or both). All dogs of other breeds were homozygous for the wild-type allele. The cDNA sequencing confirmed presence of the expected variant mRNA sequence in ocular tissue from the affected dog only. Gene expression analysis revealed a 4.24-fold decrease in the expression of ADAMTS17 in ocular tissue from the affected dog.
CONCLUSIONS AND CLINICAL RELEVANCE Results supported that the phenotype (diagnosis of POAG, PLL, or both) is an autosomal recessive trait in Shar-Pei significantly associated with the identified mutation in ADAMTS17.
Objective—To characterize the effects of oral administration of a high dose of enrofloxacin to cats.
Animals—24 (12 male and 12 female) young healthy cats.
Procedures—Cats were allocated on the basis of sex into 2 groups (4 males and 4 females/ group) from which 3 subgroups for 3 durations (3, 5, or 7 days) of enrofloxacin (50 mg/kg, PO, q 24 h) or control solution (1 mL of water, PO, q 24 h) administration that began on day −1 were created. Funduscopic examinations were performed daily. Electroretinography (ERG) was performed before and every 2 to 3 days after the start of oral administration. Four cats/study group were euthanized on days 3, 5, and 7, and eyes were collected for light and electron microscopic evaluations.
Results—Neurologic, funduscopic, and ERG abnormalities were evident only in cats administered enrofloxacin. Funduscopic changes (granular appearance or graying of the area centralis) were noticed on or before day 3 (after only 3 days of enrofloxacin administration), with subsequent similar changes along the visual streak. Vascular attenuation (between days 2 and 4) and generalized tapetal hyperreflectivity (between days 5 and 7) followed. Reduction in b-wave ERG amplitude preceded funduscopic changes. Morphologic changes in the photoreceptor layers correlated with duration of enrofloxacin administration, with generalized degenerative changes evident after 3 doses.
Conclusions and Clinical Relevance—The study indicated that a high dose of enrofloxacin (50 mg/kg/d, PO) induced retinal and systemic changes. Enrofloxacin at 10 times the recommended dosage is acutely toxic to the outer retina of clinically normal cats.
Objective—To characterize features and response to treatment of keratoconjunctivitis sicca (KCS) associated with oral administration of etodolac in dogs.
Design—Retrospective case series.
Sample Population—65 cases obtained from a survey of veterinary ophthalmologists (group A) and 146 cases reported to Fort Dodge Animal Health (group B).
Procedures—Data analyzed included breed, sex, age, weight, dose and duration of etodolac administration, results of Schirmer tear test at the time of diagnosis and last follow-up, treatments, and response to treatments. Groups A and B were analyzed separately by use of forward stepwise logistic regression models developed to predict probability of complete remission or clinical improvement as a function of several variables.
Results—Most dogs developed severe KCS (84 eyes of 50 dogs [group A]; 111 eyes of 62 dogs [group B]). Resolution of KCS occurred in 7 of 65 (A) and 23 of 146 (B) dogs. No response to treatment was observed in 26 of 65 (A) and 27 of 146 (B) dogs. Fifty-one (A) and 52 (B) dogs had records that were sufficiently complete to use in models. In group B, dogs with etodolac treatment intervals < 6 months prior to the onset of KCS were 4.2 times as likely to have remission as were dogs with treatment intervals ≥ 6 months.
Conclusions and Clinical Relevance—Shorter duration of etodolac administration (< 6 months) was associated with improved outcome in 1 population of dogs. Monitoring of tear production should be considered prior to and during administration of etodolac in dogs.
Objective—To investigate long-term outcomes and owner-perceived quality of life associated with sudden acquired retinal degeneration syndrome (SARDS) in dogs.
Animals—100 dogs with SARDS examined at 5 academic veterinary institutions from 2005 to 2010.
Procedures—The diagnosis was based on documented acute vision loss, normal results of ophthalmic examinations, and evaluation of extinguished bright-flash electroretinograms. Primary owners of affected dogs completed a questionnaire addressing outcome measures including vision, systemic signs, and perceived quality of life for their dogs.
Results—Age at diagnosis was significantly correlated with positive outcome measures; dogs in which SARDS was diagnosed at a younger age were more likely to have alleged partial vision and higher owner-perceived quality of life. Polyphagia was the only associated systemic sign found to increase in severity over time. Medical treatment was attempted in 22% of dogs; visual improvement was not detected in any. Thirty-seven percent of respondents reported an improved relationship with their dog after diagnosis, and 95% indicated they would discourage euthanasia of dogs with SARDS.
Conclusions and Clinical Relevance—Blindness and concurrent systemic signs associated with SARDS appeared to persist indefinitely, but only polyphagia increased in severity over time. Most owners believed their pets had good quality of life and would discourage euthanasia of dogs with SARDS.