Veterinary ophthalmology最新文献

Objective: To measure the eyelid margin thickness (LMT) in dogs with meibomian gland dysfunction (MGD) and evaluate its correlation with meibomian gland (MG) morphology.

Animals studied: Fifty-nine client-owned dogs.

Procedure: The LMT was measured on slit lamp biomicroscopy images and divided into groups of 1 to 4, from the thinnest to thickest, based on quartiles. MG morphology, including distortion, thickening, shortening, and dropout, was evaluated using noninvasive infrared meibography. The LMT and meibography results were compared between the MGD and normal groups. Statistical analysis was performed to determine the correlation between LMT and MG morphology.

Results: The mean LMT was significantly greater in the MGD group (1.18 ± 0.19 mm) than the normal group (1.00 ± 0.13 mm) and was positively correlated with MG loss (p < 0.01). The LMT was thicker in dogs over 12 years (1.25 ± 0.20 mm). The LMT group 4 (≥ 1.26 mm) had the highest percentage of abnormal MG (95.7%) and MG loss area (37%). The total abnormal MG ratio and thickened MG ratio were significantly higher in the LMT group 4. LMT ≥ 1.20 mm was identified as a potential indicator for MG loss area of more than one-third.

Conclusions: Eyelids with thick LMT had more abnormal MG morphology, including thickening and dropout. An LMT ≥ 1.20 mm could be a criterion to suspect MGD. Thus, the LMT could be a simple screening tool to predict MG loss and might aid in the diagnosis and early management of MGD with a sensitivity of 0.645 and a specificity of 0.768.

Objective: To evaluate the evolution of corneal sensitivity in healthy beagle puppies during the first weeks of life, compare these results with adult corneal sensitivity, and determine the age at which adult corneal sensitivity levels are reached.

Animals studied: Twelve puppies and five adult females.

Procedures: Corneal sensitivity was assessed in puppies weekly from 2 to 7 weeks of age and in their mothers by measuring the corneal touch threshold (CTT) in the central cornea using a Cochet-Bonnet esthesiometer. Hygrometric and temperature measurements were recorded throughout the study period.

Results: In puppies, esthesiometry indicated a progressive decrease in corneal sensitivity with age. Sensitivity was higher between 2 and 4 weeks, which stabilized between 5 and 7 weeks, with a median CTT values of 0.5, 0.5, 0.8, 1.4, 1.2, and 1.4 g/mm² at 2, 3, 4, 5, 6, and 7 weeks, respectively. The median CTT in puppies reached the adult median value (1.4 g/mm²) at 5 weeks. The median CTT at 2 weeks was significantly different from the median CTT at 7 weeks (0.5 vs. 1.4 g/mm²). Humidity and temperature were not significantly associated with corneal sensitivity in adults.

Conclusions: In this study, corneal sensitivity in beagle puppies was higher during the first 3 weeks of life compared to 7 weeks. During this early period, puppies exhibited corneal sensitivity levels exceeding those of adults, which subsequently decreased to adult-equivalent values between 5 and 7 weeks of age.

Objective: To investigate the level of pro-inflammatory cytokines in aqueous humor from ADAMTS10-mutant research Beagles at an early stage of open-angle glaucoma (OAG).

Animals studied: Twenty-four research Beagles were enrolled into this case-controlled study. Three groups of ADAMTS10-mutant research Beagles were enrolled in this study: (1) Intraocular pressure (IOP) 15-25 mmHg (normotensive IOP), (2) IOP 25-30 mmHg, and (3) IOP 30-36 mmHg. An unaffected control group of Beagles that were either ADAMTS10-wildtype (WT) or heterozygote-carrier with normotensive IOPs were also enrolled.

Procedures: Aqueous humor samples were collected and analyzed for 16 pro-inflammatory cytokines using the Canine Cytokine SpikeMix and target mass spectrometry via multiple reaction monitoring (MRM-MS). Statistical differences between the four groups' pro-inflammatory cytokines, as well as correlations between pro-inflammatory cytokines and IOPs, were analyzed using Kruskal-Wallis tests and Spearman's rho (ρ) correlations, respectively.

Results: IOP 15-25 mmHg (n = 8); IOP 25-30 mmHg (n = 6); IOP 30-36 mmHg (n = 5); and Control (WT n = 3, carrier n = 2, total n = 5). There were no differences between pro-inflammatory cytokines across the four groups (all p-values > 0.05). IL-13 had a moderate positive correlation with IOP, but was non-significant (ρ = 0.373, p = 0.073); IL-1β had a moderate negative correlation with IOP but was also non-significant (ρ = -0.344, p = 0.100). All other pro-inflammatory cytokines had only mild correlation with IOPs (|ρ| < 0.229, p > 0.05).

Conclusions: There were no significant changes in the investigated pro-inflammatory cytokines with elevated IOP in canine ADAMTS10-OAG.

Objective: To evaluate the effect of intravenous mannitol and hypertonic saline (HS) on intraocular pressure (IOP) and biometry parameters of horses with elevated intracranial pressure (ICP).

Procedures: Seven horses with normal ophthalmic exams were anesthetized and placed in lateral recumbency. A subarachnoid transducer was placed, and the head was lowered until ICP measured 40 mmHg +/- 2 mmHg. Five intravenous boluses of mannitol 20% (0.4 g/kg) or HS 7.2% (1 mL/kg) were administered, each 15 min apart. A 2-day washout period ensued, and the procedure was repeated with the other hyperosmotic agent. IOP via a TonoVet, axial length and vitreous chamber depth via biometry, and ICP via the subarachnoid transducer were monitored.

Results: No significant correlation between ICP and IOP was identified. Estimated marginal mean (EMM) reduction in IOP (comparing values 5 min post bolus to values at bolus administration) following mannitol and HS was 2.4 mmHg and 0.4 mmHg, respectively. Mean axial length EMM decreased by and increased by 0.1 mm following mannitol and HS, respectively. Mean vitreous chamber depth EMM was unchanged and increased by 0.1 mm following mannitol and HS, respectively. The EMM of the second HS bolus demonstrated an increase of 0.8 mm (95% confidence interval 0.01-1.5 mm) in axial length (p < 0.048), though the remaining individual bolus assessments were not statistically significant.

Conclusions: Intravenous mannitol and HS did not cause a significant change in IOP, axial length, or vitreous chamber depth in healthy, anesthetized, laterally recumbent horses in this experimental model of increased ICP.

Objective: To evaluate the accuracy of recalibrated TONOVET Plus (rTVP) and the newly released TONOVET Pro (TVPR) in measuring intraocular pressure (IOP) in ex vivo canine eyes compared to manometer and the established TONOVET (TV).

Procedure: Sixteen enucleated canine eyes were cannulated to establish manometric IOPs ranging from 5 to 80 mmHg. IOP measurements were obtained using TV, rTVP, and TVPR.

Results: All tonometers showed a strong correlation with the manometer (R² > 0.98). Measurements from rTVP and TVPR exhibited almost perfect agreement with the manometer (CCC = 0.9974 for both), whereas TV demonstrated lower agreement (CCC = 0.9874) associated with greater systematic bias. Specifically, TV showed a lower proportional bias (95% confidence interval [CI] of the slope = 0.987-1.006) but a larger systematic bias (intercept = -3.33 mmHg) compared to rTVP and TVPR (95% CI of the slope = 1.045-1.066 and 1.045-1.063; intercept = -2.532 and -2.633 mmHg, respectively). In accuracy analyses by range, rTVP and TVPR showed no significant difference from the manometer in the 30-70 mmHg and 35-80 mmHg IOP ranges, respectively.

Conclusions: Among the ICare rebound tonometers, rTVP and TVPR provided the most accurate IOP measurements in the ex vivo analysis and demonstrated particularly strong agreement in the high IOP range, suggesting their suitability for IOP measurement in glaucomatous patients.

Objective: To determine the intraocular pressure (IOP) reference values in healthy male camels using two rebound tonometers: TonoVet (TV) and TonoVet Plus (TV+), and to compare measurements between both devices and in different body positions.

Animals' studied: Thirty-four healthy, captive, adult (8-24 years and a median age of 14), male camels belonging to a zoological collection in Fuerteventura, Spain.

Methods: All camels underwent general physical examination, slit lamp biomicroscopy, and tonometry, under minimal physical restraint (headstall and chute). Three consecutive readings were acquired with TV and/or TV+ in the right and/or left eyes in standing and/or sitting positions, whenever possible. Comparisons between groups were made when paired data for the test variable was available for the same eye (for tonometer and body position) or for the same animal (for left and right eyes) using paired t-tests.

Results: The mean IOP (± standard error and range) in standing position was 18.51 mmHg (0.52, 10.33-24.33 mmHg) for TV and 19.53 mmHg (0.50, 12.33-26.33 mmHg) for TV+. In sitting position, the IOP was 14.70 mmHg (0.49, 11.33-18.33 mmHg) for TV and 16.28 mmHg (0.47, 13-19.66 mmHg) for TV+. Measurements for both TV and TV+ were significantly higher (p = 0.003 and p = 0.011, respectively) in standing position. Recordings with TV+ were significantly higher than with TV, in any body position (p < 0.001 and p = 0.006, respectively). There were no statistically significant differences between right and left eyes, except for TV+ in standing position, with the IOP in the left eye being significantly higher (20.58 mmHg versus 18.51 mmHg, p = 0.004).

Conclusions: To the authors' knowledge, this is the first report estimating the IOP reference values in male camels comparing two different rebound tonometers. Measurements for both TV and TV+ were significantly higher in the standing position. Recordings with TV+ were significantly higher than with TV (in any body position). Further studies with female individuals and different age groups are warranted.

Purpose: To describe the findings of computed tomography (CT) used to investigate signs of ophthalmic disease in pet rabbits.

Methods: Retrospective review of records of patients with signs of ophthalmic disease that underwent CT scans in three referral centers between 2001 and 2022. Signalment, presenting ophthalmic and nonophthalmic complaints, CT findings, and restrain modality were recorded.

Results: There were 85 rabbits representing 14 breeds including 28/85 (32.9%) crossbreed/unknown and 25/85 (29.4%) Dwarf rabbits. The top presenting ophthalmic complaints were ocular discharge (48/85, 56.5%), exophthalmos (34/85, 40%), and epiphora (14/85, 16.5%), while 38/85 (44.7%) rabbits also had nonophthalmic complaints. Anesthetic complications forced 1/85 (1.18%) CTs to be stopped. There were ophthalmic abnormalities in the remaining 81/84 (96.4%) CTs with exophthalmos and/or nasolacrimal duct disease affecting 76/81 (93.8%) rabbits and 68/81 (84%) also showing nonophthalmic abnormalities. Ophthalmic abnormalities were seen with nonophthalmic disease in 64/81 (79%) rabbits with dental disease being the most common (52/64, 81.3%) although only 20/52 (38.5%) had presented with dental complaints. No association was found between the presence of exophthalmos and/or NLD disease and dental disease. There were no obvious image artifacts in the 4/84 (4.8%) physically restrained patients.

Conclusion: Examination with CT in the present study mainly supported the investigation of ocular discharge, exophthalmos, and epiphora, and of possible local and systemic involvement in one eye with intraocular neoplasia. Adnexal disease was often seen with previously unknown, nonophthalmic pathology, which warrants prospective, controlled studies. Image quality studies in a large number of physically restrained patients are also warranted.

Objective: Determine the effect of oral macrocyclic lactone heartworm-preventative medications on retinal function and chromatic pupillary light reflex (cPLR) in healthy dogs.

Animals studied: Cross-sectional retrospective: 60 dogs (n = 33 females) with heartworm medication administration status and electroretinogram (ERG) data available. Prospective clinical study: 25 dogs (n = 10 females) had ERG performed, 18 of which had cPLR performed.

Procedures: Retrospective: ERG amplitudes/peak times were compared between dogs that had or had not received oral heartworm preventatives. Bivariate and multiple variable linear regression models were used to evaluate relationships between ERG testing and heartworm preventive administration status, age, and sex.

Prospective: ERG and cPLR testing were performed at a baseline visit (minimum 14 days since last preventative administration), and a second visit where ERG/cPLR testing was performed 4 h after oral preventative administration. Mixed effects models and Mann-Whitney U statistics were performed.

Results: Retrospective: There was no association between heartworm preventive administration status and ERG amplitudes or peak times (all p-values > 0.12).

Prospective: Heartworm preventative had no effect on light- and dark-adapted ERG amplitudes or peak times (all p-values > 0.56). Similarly, there was no effect on baseline pupil size (p = 0.83), nor on cPLR (p = 0.32).

Conclusion: No significant effects of oral macrocyclic lactones on retinal/cPLR function at preventative doses were identified. While small effects on retinal/cPLR function cannot be completely ruled out, it remains unlikely that these medications cause clinically significant visual deficits at prescribed doses, and proven antiparasitic benefits likely far outweigh small potential ophthalmic risks of administration.

A 6-year-old castrated male mixed breed dog presented to the "Louisiana State University Veterinary Teaching Hospital &-anonymized for review" ophthalmology service with marked exophthalmos and lagophthalmos of the left eye and soft tissue swelling medial to the zygomatic arch. A computed tomography (CT) scan was performed, and it revealed a well-marginated, lobulated, homogenously fat density involving the retrobulbar space. Preliminary results of a fine-needle aspirate (FNA) and biopsy were not conclusive, and a modified transfrontal orbitotomy was performed to remove the mass. Histopathological evaluation was diagnostic for retrobulbar infiltrative lipoma. Nine months after the surgery, the eye appears within normal limits with no evidence of recurrence.

Purpose: To describe a surgical method for correcting lower lid entropion, lateral canthal entropion, and macroblepharon.

Methods: Lid margins were incised at a 45° angle, and lateral lid margins and a rhomboid shaped piece of skin were resected based on the degree of macroblepharon. Subcutaneous tissue was sutured with absorbable sutures and anchored to the orbital ligament with a non-absorbable suture to maintain lateral canthal position. A new lateral canthus was formed using a "figure of eight" technique with absorbable sutures, and the skin was closed with simple interrupted sutures. Complications were categorized as minor (wound infections, delayed healing) or major (orbital ligament detachment).

Results: Lateral tarsorrhaphy with orbital ligament fixation was performed on 77 palpebral fissures (PF) in 39 dogs, with English Cocker Spaniels and Great Danes being the most affected breeds. Most dogs were male (72%) with a median age of 23 months; 69% were under 50 months. Of the PF treated, 57 (74%) had no complications, 11 (14%) had minor complications, and 9 (12%) had major complications, including six cases of ruptured orbital ligament fixation and one case of unilateral entropion recurrence. One dog was euthanized due to severe complications from auto-mutilation and lack of compliance.

Conclusion: This surgical method effectively corrects diamond-shaped eyes, although complications can occur, especially in male dogs with excessive facial skin.