Background There has not been a thoroughly reported study of the comparison between spectral domain-optical coherence tomography (SD-OCT) with both ultrasound biomicroscopy (UBM) and gonioscopy on the evaluation of the iridocorneal angle (ICA) in dogs. Objectives To investigate the diagnostic value of SD-OCT for the early detection of narrowing ICA by comparing and assessing inter-device agreement in anterior chamber angle (ACA) measurements obtained by SD-OCT and UBM, and ICA evaluations by gonioscopy. Methods A total of 28 eyes from 28 client-owned dogs with normal intraocular pressure were included for examination. The ACA and angle opening distance (AOD) were measured from the SD-OCT and UBM images, and gonioscopy images were analyzed using the ICA grade and ZibWest angle index. Results The mean ACA and AOD for SD-OCT were 28.31° ± 5.37° and 658.42 ± 219.90 µm, and for UBM, 28.34° ± 5.82° and 859.29 ± 221.80 µm, respectively. The mean difference in ACA between the average values of SD-OCT and UBM measurements was 0.03° with a 95% limit of agreement (LoA) span of 16.2°, indicating positive agreement; that in AOD was 200.85 µm with a 95% LoA span of 1,110.95 µm, indicating poor agreement. The Pearson correlation coefficient of the ACA of SD-OCT and ZibWest indices of gonioscopy was 0.624, indicating strong agreement; that of UBM and gonioscopy was 0.43, indicating moderate agreement. Conclusions SD-OCT is well tolerated by canine patients due to its non-contact method and might be an alternative option for early screening of ICA narrowing in clinical settings.

This study aimed to investigate the effect of mydriasis using topical rocuronium bromide on electroretinography (ERG) in domestic pigeons (Columba livia). Scotopic mixed rod and cone, photopic cone, and photopic flicker ERG were performed on nine eyes of nine healthy adult pigeons under sedation. Each pigeon underwent two sets of ERG recordings. First, without the induction of mydriasis (control) and the second time with the induction of mydriasis using topical rocuronium bromide (treatment). The results were compared using either the Student's t-test or Wilcoxon rank-sum test, where a P-value of < 0.05 was considered statistically significant. No significant differences were observed in the a-and b-wave implicit times and amplitudes during scotopic ERG between the two groups. The a-and b-wave amplitudes in the photopic cone were significantly higher in the treatment group (63.83 ± 32.33 and 191.75 ± 94.46 µV) compared to the control group (46.15 ± 27.60 and 116.76 ± 70.65 µV; P = 0.045 and P = 0.032, respectively). The photopic flicker amplitude was also significantly higher in the treatment group (76.23 ± 48.56 µV) than in the control group (42.18 ± 31.18 µV; P = 0.044). No statistically significant differences were observed in the photopic cone and flicker implicit times between both groups. In conclusions, mydriasis induced by rocuronium bromide in pigeon resulting in higher amplitudes during the photopic ERG but not scotopic ERG.

ObjectiveTo present the clinical signs and treatment methods for atypical tumor‐like meibomitis in two dogs.Animals StudiedA 4‐year‐old castrated‐male Coton de Tulear (Case 1) and a 6‐year‐old spayed‐female Maltese dog (Case 2).ProcedureFull ophthalmic examination revealed a well‐circumscribed, firm, and raised solitary mass on the upper eyelid of the left (Case 1) and right eye (Case 2). Case 1 showed a recurrent mass with a diameter of 2–3 mm, which was excised by the referring veterinarian. The possibility of meibomian gland involvement was suggested histopathologically. Case 2 had a history of blepharitis treated with systemic corticosteroids 4 years ago.ResultsTopical and systemic antibiotics and anti‐inflammatory drugs were administered to reduce inflammation and prevent secondary infections. In Case 1, the mass appeared static at the beginning of medication; however, after stopping antibiotics while tapering steroids, the mass increased in size and was associated with suppurative discharge. In Case 2, the mass continued to grow despite treatment, showing a similar infection pattern. Cytological examination revealed neutrophilic inflammation with cocci infection, and bacterial culture confirmed the presence of Staphylococcus pseudintermedius in both cases. When steroid administration was stopped and antibiotic administration was initiated according to the results of the antibiotic susceptibility test, the mass rapidly decreased in size and completely disappeared. There was no recurrence on follow‐up.ConclusionsA unilateral antibiotic‐responsive tumor‐like solitary mass on the upper eyelid resolved without surgical treatment. Medical treatment must be considered when treating atypical eyelid masses, and the use of appropriate antibiotics through antibiotic susceptibility testing is important.

A 3-year-old spayed female beagle dog was presented with epiphora, severe hemorrhagic and purulent ocular discharge in the right eye (OD). A reflux of the discharge through the other canaliculi, associated with signs of chronic inflammation, was observed on cytology. Dacryocystorhinography revealed retention of contrast media ventral to the lower punctum, indicating complete obstruction and the potential presence of radiolucent foreign body. Ocular discharge subsided after the first treatment, including flushing of the nasolacrimal duct and application of topical antibiotics and corticosteroids, but clinical symptoms of the dacryocystitis waxed and waned thereafter. Surgical treatment was delayed for 8 months due to Dirofilaria immitis infection, and topical treatment and monthly flushing were maintained. On the day of operation, a foreign body was released through the fistula, while flushing for disinfection under general anesthesia, just before the surgery. Dacryocystectomy was performed to remove necrotic tissue and residual foreign body around the nasolacrimal cyst. Upon histopathologic findings, the removed foreign body was considered to be a plant, and the nasolacrimal cyst was comprised of chronic active ulcerative inflammation and necrotic tissues. At the 1-week recheck, improvement of epiphora and ocular discharge and healing of the surgical site was noted. In conclusion, nasolacrimal duct foreign body can be considered in recurrent dacryocystitis, despite nasolacrimal flushing and topical medication. In this study, dacryocystectomy was curative without recurrence of dacryocystitis or epiphora.

Notification on spelling errors in the co-author's name: 'Dumin Ko' was changed to 'Dumin Go' due to incorrect spelling of the English name of the co-author, written in p.152 of this paper.