Clinical and echocardiographic evaluations of sedative and cardiovascular effects of combination of xylazine-acepromazine versus xylazine-pregabalin in horses.

The aim of this study was to compare the sedative and cardiovascular effects of the combination of xylazine-acepromazine versus xylazine-pregabalin - in horses. Four healthy crossbred horses were included in the study and assigned to two treatments. In treatment I (T1), the animals received xylazine hydrochloride (1.00 mg kg-1) in combination with acepromazine maleate (0.05 mg kg-1) intravenously. In treatment II (T2), the animals received intragastric administration of pregabalin (4.00 mg kg-1) followed by xylazine hydrochloride (1.00 mg kg-1) intravenously after 60 min. Head height above ground (HHAG) and echocardiographic indices were evaluated. In T1, recordings were made 5 minubefore and 5, 15, 30, 60, and 90 minu after drug administration. In T2, recordings were made 5 min before pregabalin, 55 minu after pregabalin administration, and then 5, 15, 30, 60, and 90 min after xylazine hydrochloride acepromazine injection. Analyses of the data showed there were no significant differences regarding HHAG and echocardiographic indices between the two treatments. Intragastric administration of pregabalin prior to xylazine could be considered as an alternative premedication regimen when acepromazine administration is contraindicated or undesirable.

Evaluation of diabetic retinopathy severity on ultrawide field colour images compared with ultrawide fluorescein angiograms.

PURPOSE: To compare Early Treatment Diabetic Retinopathy Study (ETDRS) diabetic retinopathy (DR) severity on ultrawide field (UWF) colour imaging (CI) and UWF fluorescein angiography (FA). DESIGN: Cross-sectional retrospective review. SUBJECTS: Patients with diabetes mellitus and at least mild non-proliferative DR on UWF-CI. METHODS: UWF-CI and UWF-FA images acquired within 1 month of each other were evaluated independently using ETDRS DR Severity Scale (DRSS) for colour photography adapted for UWF-CI and UWF-FA. Extent of non-perfusion (NP, mm2) was determined from UWF-FA images. MAIN OUTCOME MEASURES: Agreement rate between DRSS on UWF-CI and UWF-FA. RESULTS: Images from 218 eyes of 137 patients with diabetes were evaluated. Agreement rate for DRSS between UWF-CI and UWF-FA was moderate to substantial (K=0.46, Kw=0.65). Over-all, DRSS was worse in 73 (33.5%) eyes on UWF-FA and in 16 (7.3%) on UWF-CI. Compared to UWF-CI, UWF-FA identified more severe DRSS in 26.5% (1 step) and 7.34% (≥2 steps) of eyes. DRSS was worse than UWF-FA in 56 (51.4%) in early DR (ETDRS levels 20-47, N=109) and 17 (15.6%) in eyes with severe DR (53 and higher, N=109). In this cohort, the extent of NP significantly increased as eyes approach moderate non-proliferative DR (levels 43-47, p=0.0065). CONCLUSION: When evaluating UWF-FA images using the ETDRS colour severity scale, DRSS is graded as more severe in a substantial number of eyes than when evaluating UWF-CI. It is uncertain how the DRSS levels using UWF-FA translate to clinical outcomes, but the additional lesions detected might provide added prognostic value. These and other recent data emphasise the need of obtaining outcome data based on UWF-FA and the potential need to develop DRSS specifically tailored for UWF-FA images.

Retinal Vascular Caliber Association with Nonperfusion and Diabetic Retinopathy Severity Depends on Vascular Caliber Measurement Location.

PURPOSE: To evaluate the association of retinal nonperfusion and diabetic retinopathy (DR) severity with location of vascular caliber measurement using ultrawide field (UWF) imaging. DESIGN: Retrospective image review. PARTICIPANTS: Adults with diabetes mellitus. METHODS: All images from subjects with same-day UWF fluorescein angiography (FA) and color imaging were evaluated. Predominantly peripheral lesions (PPL) and DR severity were graded from UWF color images. Nonperfusion was quantified using UWF-FA in defined retinal regions [posterior pole (PP), mid-periphery (MP), far-periphery (FP)]. Retinal vessel calibers were measured at an optic disc centered inner and outer zone. MAIN OUTCOME MEASURES: Nonperfusion index (NPI) in the PP, MP and FP. Mean arteriole and venule diameter in the inner and outer zones. RESULTS: Two hundred eighty-five eyes of 193 patients (24.9% mild nonproliferative DR [NPDR], 22.8% moderate NPDR, 37.5% severe NPDR and 14.7% proliferative DR [PDR]) were reviewed. No significant associations between inner zone arteriolar diameter and retinal NPI overall or in any retinal region. In the outer zone, eyes with thinnest arteriolar calibers (quartile 1) were associated with a 1.7- to 2.4-fold nonperfusion increase across all retinal regions compared to the remaining eyes (P = 0.002 [PP] to 0.048 [FP]). In the outer zone, the percentage of eyes in the thinnest quartile of retinal arteriolar diameter increased with worsening DR severity (mild NPDR: 10% vs PDR: 31%, P = 0.007). This association was not observed when measured within the inner zone (P = 0.129). All venular caliber associations were not statistically significant when corrected for potentially confounding factors. Thinner outer zone retinal arteriolar caliber (quartile 1) was more common in eyes with PPL compared to eyes without PPL (34.1% vs 20.8%, P = 0.017) as were thicker outer venular calibers (quartile 4) (33% vs 21.3%, P = 0.036). Presence of PPL was associated with thinner outer zone arteriolar caliber (109.7 ± 26.5µm vs 123.0 ± 29.5µm, P = 0.001). CONCLUSIONS: The association of vascular caliber with nonperfusion and DR severity differs based upon the retinal location at which vascular caliber is measured. Peripheral arterial narrowing is associated with increasing nonperfusion, worsening DR severity and presence of PPL. In contrast, inner zone retinal arteriolar caliber is not associated with these findings.

Diabetic retinopathy and ultrawide field imaging.

The introduction of ultrawide field imaging has allowed the visualization of approximately 82% of the total retinal area compared to only 30% using 7-standard field Early Treatment Diabetic Retinopathy (ETDRS) photography. This substantially wider field of view, while useful in many retinal vascular diseases, is particularly important in diabetic retinopathy where eyes with predominantly peripheral lesions or PPL have been shown to have significantly greater progression rates compared to eyes without PPL. In telemedicine settings, ultrawide field imaging has substantially reduced image ungradable rates and increased rate of disease identification allowing care to be delivered more effectively. Furthermore, the use of ultrawide field fluorescein angiography allows the visualization of significantly more diabetic retinal lesions and allows more accurate quantification of total retinal nonperfusion, with potential implications in the management of diabetic retinopathy and diabetic macular edema. The focus of this paper is to review the current role of ultrawide field imaging in diabetic retinopathy and its possible future role in innovations for retinal image analysis such as artificial intelligence and vessel caliber measurements.

Comparison of the effect of cycloplegic versus NSAID eye drops on pain after photorefractive keratectomy.

PURPOSE: To compare the effect of Homatropine and Diclofenac eye drops for reducing pain after photorefractive keratectomy (PRK). METHODS: This randomized, double-masked, interventional study included 32 patients (64 eyes) who underwent bilateral PRK. After operation, patients received Homatropine eye drops in one eye and Diclofenac eye drops in the fellow eye for 48 h. The level of pain was evaluated using visual analogue scale (VAS), verbal rating scale (VRS), and pain rating index (PRI) at 0.5, 24, and 48 h after operation. RESULTS: The level of pain was statistically similar between the two eyes half an hour after operation; however, Diclofenac eyes had significantly less pain 24 h after operation (1.7 ± 1.4 vs 5.8 ± 2.1, P < 0.001 for VAS, 0.6 ± 0.6 vs 2.4 ± 1.1, P < 0.001 for VRS, and 3.4 ± 3.4 vs 12.0 ± 6.9, P < 0.001 for PRI, respectively). Also, 48 h after surgery, the pain scores were less in the Diclofenac eyes (1.6 ± 1.8 vs 3.4 ± 2.8, P < 0.001 for VAS, 0.6 ± 0.6 vs 1.2 ± 0.9, P < 0.001 for VRS, and 3.3 ± 3.7 vs 6.5 ± 6.2, P < 0.001 for PRI). No case with delayed epithelial healing in both groups was observed. CONCLUSION: The effect of Homatropine seems to be lower compared to Diclofenac for reducing pain after photorefractive keratectomy.

Effect of Homatropine eye drops on pain after photorefractive keratectomy: A pilot study.

PURPOSE: To assess the effect of homatropine eye drops on pain after photorefractive keratectomy (PRK). METHODS: This randomized, double masked, interventional study included 15 patients (30 eyes) who underwent bilateral PRK. After operation, patients received homatropine eye drops, 4 times daily in only one eye (homatropine eye). The level of pain was evaluated using visual analogue scale (VAS), verbal rating scale (VRS) and pain rating index (PRI) at 0.5, 24 and 48 h after operation. RESULTS: The level of pain was statistically similar between the two eyes half an hour after operation, however, homatropine eyes had significantly less pain 24 h after operation compared to fellow eyes (2.5 ± 1.9 vs 5.3 ± 2.5, P = 0.004 for VAS, 2.0 ± 1.2 vs 3.2 ± 0.9, P = 0.023 for VRS, and 9.4 ± 5.7 vs 16.0 ± 9.0, P = 0.031 for PRI). Also, 48 h after surgery, the pain scales were less in the homatropine eyes (2.3 ± 1.7 vs 4.0 ± 2.1, P = 0.014 for VAS, 1.6 ± 1.0 vs 2.5 ± 1.0, P = 0.038 for VRS, and 6.8 ± 5.7 vs 12.0 ± 8.9, P = 0.005 for PRI). No delayed epithelial healing was observed. CONCLUSION: Homatropine eye drops may be useful for reducing pain after Photorefractive keratectomy.

Intraocular pressure-lowering effect of 0.005% latanoprost with two different dosing regimens.

PURPOSE: To compare the intraocular pressure (IOP)-lowering effect of 0.005% latanoprost used once every other day versus once daily in patients with primary open-angle glaucoma (POAG) or ocular hypertension (OHT). METHODS: Forty eyes of 20 patients with bilateral OHT or early POAG were enrolled in this prospective, randomized, crossover study. After a washout period of 1-4 weeks, each patient started latanoprost once daily in 1 randomly assigned eye and once every other day in the other eye. After 1 month, eyes were crossed over to the opposite dosing regimen for another month. IOP was measured at 9 am, 4 pm, and 9 pm, both at baseline and on 2 consecutive days, at the end of the first and second months. The main outcome measure was IOP reduction on the second day at the end of the first and second months. RESULTS: Mean±standard deviation (SD) baseline IOPs (mmHg) in the right and left eye were 25.6±2.6 and 25.5±2.7 (P=0.8), respectively. Mean±SD diurnal IOPs decreased (mmHg) by 8.6±2.5 in the once-daily group versus 7.3±2.3 in the every-other-day group (P<0.001) at the end of the first month and 8.4±2.5 versus 7.7±2.5 at the end of the second month (both on day 2) (P=0.01). CONCLUSIONS: Once every-other-day administration of latanoprost significantly reduced the IOP although the IOP reduction was less pronounced 36-48 h after drug application.