Effects of conditioned media from human amniotic epithelial cells on corneal alkali injuries in rabbits.

This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits.

Comparison of two electroretinography systems used in dogs: the HMsERG and the RETIport.

The purpose of the study was to compare two different electroretinography (ERG) instruments used on the same animal in a laboratory setting. Retinal function in both eyes of 12 healthy miniature schnauzers was evaluated under general anesthesia. Scotopic and photopic ERGs were recorded by the HMsERG and the RETIport using the Dog Standard Protocol recommended by the European College of Veterinary Ophthalmologists (ECVO). The waveforms of the ERGs obtained by the two ERG units were similar to those described in previous studies. The 90% reference ranges using the multiple of medians (MoM) showed that the changes in ERG parameters obtained by the HMsERG unit were very similar to those of the RETIport for most ERG responses, except for a few. The results demonstrate that the two ERG systems are comparable for evaluating retinal function in dogs. Further, the results also show that it is necessary to establish ERG system-specific limits of normality in each laboratory or clinic in order to obtain a correct diagnosis, for example by using a graphical representation of the 90% reference range.

Assessment of experimental saccular aneurysm using selective angiography in common carotid artery of rabbits.

In order to study the treatment of aneurysms, the technique of making experimental aneurysms in laboratory animals must be established. In our study, to examine the feasibility of making experimental aneurysm and selective angiography on the common carotid artery in rabbits and to determine the size of experimental aneurysm after surgery, saccular aneurysms were fashioned on the right common carotid artery in 17 rabbits using a vein pouch technique. Selective angiography of the common carotid artery was performed immediately after surgery, and at 1 week, 4 weeks, and 8 weeks after surgery. Also, histological changes in the aneurysms were observed. In 16 rabbits with established successful experimental aneurysm, no differences were found in diet intake and behavior before and after surgery. The patency of the carotid artery was confirmed by selective angiography. The average size of the aneurysm immediately after surgery was similar to that of 1 week postoperatively in selective angiography, however it increased with time at 4weeks and 8 weeks. Histologically, infiltration of inflammatory cells and hemorrhage were found at the junction of the carotid artery and the vein pouch at 1 week, which disappeared at 4 weeks and 8 weeks. This study suggests experimental saccular aneurysm using the vein pouch technique might form aneurysms similar to that of the human in its properties such as increment of size, and selective angiography might be suitable for assessment of experimental aneurysm. Therefore, this animal model may be suitable for investigating new treatment methodologies for human aneurysms.

Evaluation of the mydriatic effect of intracameral lidocaine hydrochloride injection in eyes of clinically normal dogs.

OBJECTIVE-To evaluate the mydriatic effect of intracameral injection of preservative-free 1% and 2% lidocaine hydrochloride solutions and determine the onset and duration of mydriasis according to the concentration and volume of lidocaine administered in healthy dogs. ANIMALS-5 healthy adult Beagles weighing 7 to 10 kg, with no apparent ocular disease. PROCEDURES-A double-blind randomized 9-session crossover trial was designed. Both eyes were assigned to 9 treatments with a minimum 7-day washout period between treatments: 0.1, 0.2, and 0.3 mL of 2% lidocaine solution; 0.1, 0.2, and 0.3 mL of 1% lidocaine solution; and 0.1, 0.2, and 0.3 mL of balanced salt solution. Dogs were anesthetized, and the allocated treatment was injected intracamerally after aspiration of the same volume of aqueous humor from the anterior chamber of each eye. Two perpendicular pupil diameters were measured. Intraocular pressure, heart rate, respiratory rate, ECG readings, and end-tidal partial pressure of CO(2) were monitored. RESULTS-Intracameral injection of 1% or 2% lidocaine solutions in volumes of 0.1 to 0.3 mL induced a significant degree of mydriasis, and the effect was maintained for 74 to 142 minutes. Lidocaine injection had no significant effect on intraocular pressure, heart rate, respiratory rate, ECG readings, or end-tidal partial pressure of CO(2). CONCLUSIONS AND CLINICAL RELEVANCE-Intracameral lidocaine injection in healthy dogs induced mydriasis, the timing of which was affected by concentration and volume of lidocaine. This technique could serve as an alternative to topically administered mydriatics for intraocular surgery in dogs.

Clinical manifestations of cataracts in small breed dogs.

OBJECTIVE: To determine the incidence, etiology, and concurrent ophthalmic findings in small breed dogs that presented with cataracts. ANIMAL STUDIED: Five hundred and sixty-one small breed dogs (942 eyes) were presented to the Veterinary Medical Teaching Hospital of Seoul National University between July 2002 and December 2007 with cataract. PROCEDURE: The medical records of small breed dogs with cataract were reviewed. The reason for presentation, cataract duration, bilaterality, breed, gender, age, vision, etiology, stage of cataract development, concurrent ophthalmic findings, IOP, ocular ultrasonography findings, and scotopic electroretinography (ERG) findings were investigated. RESULTS: The most frequently presented breeds were the Miniature/Toy Poodle (n = 112, 20.0%), Yorkshire Terrier (n = 110, 19.6%), and Shih Tzu (n = 95, 16.9%). The Miniature/Toy Poodle showed a significantly higher odds ratio for cataract formation (2.6). The proportion of female cataract patients was significantly higher than that of male cataract patients in the overall population (P < 0.05). The Miniature/Toy Poodles had significantly higher numbers of females affected with cataract (P < 0.01). The mean age for cataract formation was 8.3 +/- 3.9 years. The mean age at onset in the Miniature/Toy Poodle and Yorkshire Terrier was significantly higher, whereas that in the Miniature Schnauzer group was significantly lower (P < 0.0001). Clinical signs related to lens induced uveitis had a tendency to increase with cataract progression (P < 0.05). There were no significant differences in the b-wave amplitude for mixed rod cone response by stage (P = 0.137). CONCLUSIONS: Small breed dogs with cataracts had characteristics with regard to age of onset and gender distribution, depending on the breed.

Combination auriculopalpebral nerve block and local anesthesia for placement of a nictitating membrane-to-superotemporal bulbar conjunctiva flap in dogs.

The purpose of this study was to evaluate the efficacy of combined local anesthesia in dogs undergoing nictitating membrane (NM)-to-superotemporal bulbar conjunctiva flap construction. Medical records of 47 dogs that had received local anesthesia for NM-to-superotemporal bulbar conjunctiva flap were reviewed. Combined local anesthetic technique included auriculopalpebral nerve block, topical anesthesia of the eye, and infiltration anesthesia of the superotemporal bulbar conjunctiva and palpebral surface of the NM. Forty-two (89.3%) dogs complied with the anesthetic procedures and underwent NM flap without general anesthesia or sedation. No complications were related to the combined local anesthesia. Combined local anesthesia for NM-to-superotemporal bulbar conjunctiva flap may be a time- and cost-effective method that produces both analgesia of the surgical site and akinesia of the eyelid.

Comparison of orbital prosthesis motility following enucleation or evisceration with sclerotomy with or without a motility coupling post in dogs.

OBJECTIVE: To evaluate motility of silicone orbital implants and corneoscleral prostheses, with and without use of a motility coupling post (MCP) in dogs. ANIMALS STUDIED: Eighteen mixed-breed dogs. PROCEDURES: The motility of an orbital silicone implant and corneoscleral prosthesis after enucleation (n = 6), evisceration (n = 6), or use of a MCP with evisceration (n = 6) in dogs were compared. One eye from each dog had surgery whereas the opposite eye was used as a control. Clinical evaluations were performed three times a week. Histopathology of the orbital tissues was performed 8 and 12 weeks after surgery. RESULTS: Implant motility in dogs with evisceration (vertical movement [VM] 8.04 +/- 2.13; horizontal movement [HM] 11 +/- 3.05) and evisceration with MCP (VM 9.61 +/- 1.59); HM was significantly greater than the enucleation group (VM 0.51 +/- 0.5; HM 1.22 +/- 0.68) (P < 0.01). Prosthetic motility in dogs with evisceration with MCP was significantly greater than in dogs with evisceration; dogs with evisceration had significantly greater motility than dogs with enucleation (P < 0.01). No postoperative complications were observed in any of the groups. No significant abnormalities were noted on histopathology. CONCLUSIONS: MCP placement in silicone orbital implants significantly enhanced the prosthetic motility in dogs. This study supports the use of MCP in silicone orbital implants to enhance corneoscleral prosthesis motility and cosmetics in dogs.

Comparison of the effects of three different combinations of general anesthetics on the electroretinogram of dogs.

The objective of this study is to compare the effects of three different anesthetic combinations on the electroretinogram in the same animals under similar laboratory conditions. Thiopental-isoflurane (TI), medetomidine-ketamine (MK), and xylazine-ketamine (XK) were used on each of 12 healthy miniature schnauzer dogs (MS) with a period of at least 3 weeks in between subsequent anesthesia protocols, using the Dog Standard Protocol. The scotopic ERGs consisted of scotopic low stimulus strength (S) responses designated S1, S2, S3, S4, and S5, at 1, 5, 10, 15, and 20 min after dark adaptation, respectively, and scotopic standard stimulus strength (S-ST) responses. The photopic ERGs consisted of a photopic single flash (P) response and 31 Hz flicker (P-FL) responses. For S-ST (2.5 cd s/m(2)), the amplitude of the a-wave using TI was significantly lower than that using MK (adjusted P = 0.05) and XK (adjusted P = 0.03), and the implicit time of the a-wave was significantly shorter than that using MK (adjusted P = 0.04). For P (2.5 cd s/m(2)), the amplitude of the b-wave using XK was significantly higher than that using MK (adjusted P = 0.01). The implicit times of the b-wave using TI was significantly longer and shorter than that of MK for S1, S2 and P-FL and for S4 and S-ST, respectively, and than that of XK for S2 and P-FL and for S5 and S-ST, respectively. The results of the present study showed that TI affected both the amplitude and the implicit time of the a-wave for S-ST and the implicit time of the b-wave relatively more so than was the case when using XK or MK. Therefore, it appears that either XK or MK could be advantageous to use rather than TI for clinical studies.

Effects of stimulus intensity for electroretinogram in conscious Miniature Schnauzers.

The aim of this study was to determine the most effective light intensity for flash electroretinogram (ERG) examination in conscious dogs using ERG equipment with a contact lens electrode with a built-in LED light source. ERG was performed on the bilateral eyes of ten clinically healthy Miniature Schnauzers at 6 different intensities (0.025, 0.079, 0.25, 0.79, 2.5 and 7.9 cd.s/m2) after dark adaptation for 20 min. With the increase in stimulus intensity, the most significant increase in a and b-wave amplitudes were observed at 2.5 cd.s/m2 (p<0.05). As the intensity of light was increased, the implicit times of both waves significantly decreased. Therefore, the most effective intensity of stimulus was 2.5 cd.s/m2 in the conscious Miniature Schnauzers. This suggests that this procedure would be applicable for evaluation of retinal function in conscious dogs, especially in high-risk patients.

Segmental aplasia of the uterine horn with ipsilateral renal agenesis in a cat.

A nine-month-old domestic short haired cat was admitted with the history of acute vomiting, depression and shivering. Abdominal ultrasonography revealed minimum enlargement of the right uterine horn filled with anechoic fluid. On excretory urography, functionally and anatomically normal, enlarged left kidney was found, but right kidney was absent. It was preliminary diagnosed as hydrometra with right renal agenesis. Aiming at the correction of hydrometra, we performed ovariohysterectomy. During spaying, we found a missing segment of distal part of the right uterine horn and absence of ipsilateral kidney and ureter. Compressed uterine structure and segmental aplasia of right uterine horn were found in histopathological investigation. Taken together, it was diagnosed as a segmental aplasia of uterine horn with ipsilateral renal agenesis.

Effects of electroacupuncture on intraocular pressure and hemodynamic parameters in isoflurane anesthetized dogs.

The effects of electroacupuncture (EA) on intraocular pressure (IOP) and hemodynamic parameters were evaluated in isoflurane anesthetized 10 (5 males, 5 females) normal mongrel dogs (8.1-9.8 kg, 6-8 years old). After determination of baseline IOP and hemodynamic parameters (cardiac index, systolic arterial pressure, diastolic arterial pressure, heart rate and systemic vascular resistance index), EA was applied at 3 acupoints (LI-4, LIV-3 and GB-37) for 20 min. After the EA treatment, IOP was significantly decreased in the both eyes (p<0.05). However, there were not significant differences in hemodynamic parameters between those of before and after EA treatment. From these results, the EA treatment at LI-4, LIV-3 and GB-37 would be considered one of the valuable methods for the IOP treatment in dogs.

Comparison of the rebound tonometer (TonoVet) with the applanation tonometer (TonoPen XL) in normal Eurasian Eagle owls (Bubo bubo).

OBJECTIVE: To examine the feasibility and accuracy of a handheld rebound tonometer, TonoVet, and to compare the intraocular pressure (IOP) readings of the TonoVet with those of an applanation tonometer, TonoPen XL, in normal Eurasian Eagle owls. ANIMALS STUDIED: Ten clinically normal Eurasian Eagle owls (20 eyes). PROCEDURES: Complete ocular examinations, using slit-lamp biomicroscopy and indirect ophthalmoscopy, were conducted on each raptor. The IOP was measured bilaterally using a rebound tonometer followed by a topical anesthetic agent after 1 min. The TonoPen XL tonometer was applied in both eyes 30 s following topical anesthesia. RESULTS: The mean +/- SD IOP obtained by rebound tonometer was 10.45 +/- 1.64 mmHg (range 7-14 mmHg), and by applanation tonometer was 9.35 +/- 1.81 mmHg (range 6-12 mmHg). There was a significant difference (P = 0.001) in the IOP obtained from both tonometers. The linear regression equation describing the relationship between both devices was y = 0.669x + 4.194 (x = TonoPen XL and y = TonoVet). The determination coefficient (r(2)) was r(2) = 0.550. CONCLUSIONS: The results suggest that readings from the rebound tonometer significantly overestimated those from the applanation tonometer and that the rebound tonometer was tolerated well because of the rapid and minimal stress-inducing method of tonometry in the Eurasian Eagle owls, even without topical anesthesia. Further studies comparing TonoVet with manometric measurements may be necessary to employ rebound tonometer for routine clinical use in Eurasian Eagle owls.

The determination of dark adaptation time using electroretinography in conscious miniature Schnauzer dogs.

The optimal dark adaptation time of electroretinograms (ERG's) performed on conscious dogs were determined using a commercially available ERG unit with a contact lens electrode and a built-in light source (LED-electrode). The ERG recordings were performed on nine healthy Miniature Schnauzer dogs. The bilateral ERG's at seven different dark adaptation times at an intensity of 2.5 cd.s/m(2) was performed. Signal averaging (4 flashes of light stimuli) was adopted to reduce electrophysiologic noise. As the dark adaptation time increased, a significant increase in the mean a-wave amplitudes was observed in comparison to base-line levels up to 10 min (p < 0.05). Thereafter, no significant differences in amplitude occurred over the dark adaptation time. Moreover, at this time the mean amplitude was 60.30 +/- 18.47 microV. However, no significant changes were observed for the implicit times of the a-wave. The implicit times and amplitude of the b-wave increased significantly up to 20 min of dark adaptation (p < 0.05). Beyond this time, the mean b-wave amplitudes was 132.92 +/- 17.79 microV. The results of the present study demonstrate that, the optimal dark adaptation time when performing ERG's, should be at least 20 min in conscious Miniature Schnauzer dogs.

Effects of Atipamezole and Naloxone on Electroencephalographic Spectral Edge Frequency 95 in Dogs Sedated by Acupuncture at GV20 and Yintang Point.

The purpose of this study was to evaluate the antagonism of acupuncture-induced sedation by electroencephalographic spectral edge frequency (SEF) 95 in 10 healthy intact male Miniature Schnauzer dogs (4.2-6.1kg; 2-3 years old) without neurological disorder. The GV20 and Yintang acupoints were administered for 20 min. While the dogs were conscious, SEF 95 baseline values were recorded at 2-min intervals for 4 min. Then acupuncture was administered at the GV20 and Yintang acupoints. During the acupuncture procedure, the SEF 95 values were recorded at 2-min intervals for 10 min. Subsequently, antagonist drugs, naloxone and atipamezole, were administered through the cephalic vein. The SEF 95 values were then measured again at 2-min intervals for 10 min. Those values were found to be significantly increased after administration of atipamezole in dogs sedated by acupuncture at the GV20 and Yintang acupoints (p<0.05). However, the SEF 95 values in the naloxone groups did not show any significant changes before and after administration of the antagonist. It was concluded that sedation induced by acupuncture at the GV20 and Yintang acupoints might be partially associated with the alpha(2)-adrenergic system.

Phacoemulsification and acryl foldable intraocular lens implantation in dogs: 32 cases.

This study evaluated the surgical outcome and complications of phacoemulsification and the implantation of an acryl foldable intraocular lens (IOL) with a squared edge in dogs with cataracts. Thirty-two eyes from 26 dogs were examined. The mean follow up period was 75.9 days ranging from 23 to 226 days. The complications after phacoemulsification were posterior capsular opacity (PCO) around the IOL (n = 11), ocular hypertension (n = 4), focal posterior synechia (n = 4), hyphema (n = 3) and corneal ulcer (n = 2). The complications associated with the IOL were decenteration of the optic (n = 2) and ventral haptic displacement (n = 1). Most cases of PCO were found only around the margin of the IOL, and all eyes had vision during the observation period. In conclusion, the implantation of an acryl-foldable lens with a squared edge at the time of phacoemulsification is an effective method for preserving the central visual field of dogs with cataract.

Study on the ophthalmic diseases in ICR mice and BALB/c mice.

In pharmaceutical companies and research institutes, many toxicity tests are performed with laboratory animals. This study was performed to produce reference data for eye toxicity tests and to investigate the ophthalmic diseases of 408 ICR mice and 119 BALB/c mice, which are commonly used as subjects in toxicity tests. The experimental animals without clinical disorders were selected regardless of sex. The ophthalmic diseases were examined by using special ophthalmic instruments: direct ophthalmoscope, indirect ophthalmoscope, slit-lamp biomicroscope and focal illuminator. The most prevalent ocular variation within normal limits was hyaloid vessel remnant (ICR mice, 28.2%; BALB/c mice, 31.9%) and the incidence gradually decreased with age. The ocular diseases found in ICR mice were retinal degeneration (9.8%), corneal scar (4.2%), focal cataract (2.2%), anisocoria (1.2%), corneal ulcer (0.2%) and uveitis (0.2%). In BALB/c mice, corneal scar (9.2%), focal cataract (1.7%) and corneal ulcer (0.8%) were the ocular diseases found.

Malignant ocular melanoma in a dog.

A mongrel male dog of three years old was referred to the Seoul National University Veterinary Teaching Hospital following a one month history of glaucoma. On ophthalmic examination, hyphema, glaucoma, uveitis, iridal mass, and loss of vision were noted in the right eye. Ultrasonography and computed tomography revealed a mass with involvement of the entire uvea. Radiographic evaluation did not reveal any evidence of distant metastasis. The right eye was surgically removed because of the high likelihood of neoplasia. A histologic diagnosis of malignant uveal melanoma was made.

Evaluation of sedation on electroencephalographic spectral edge frequency 95 in dogs sedated by acupuncture at GV20 or Yintang and sedative combination.

The spectral edge frequency (SEF) 95 is one of the electroencephalographic (EEG) parameters, which is a relatively simple and effective method to evaluate a sedative status. The aim of this study was to evaluate the effect of acupuncture on electroencephalographic SEF 95 in dogs (4.2 - 6.1 kg, 1-2 years old) sedated by a sedative. The acupoints used were the GV20 point and Yintang point. The sedatives used were acepromazine, butorphanol, diazepam, medetomidine, and phenobarbital, each using a different mechanism. The sedation level was assessed by a SEF 95 value under normal conditions, sedation being induced by a sedative, a combination of a sedative and acupuncture, and acupuncture release. During the sedative and acupuncture combination, the SEF 95 values significantly decreased in the butorphanol group. Although this result was just based on the changes of the brain it is suggested that acupuncture, combined with opioids, would be a useful method to produce a safe and deep sedation in clinics.

Spontaneous ophthalmic diseases in 586 New Zealand white rabbits.

The purpose of this study was to investigate spontaneous eye disease in New Zealand White (NZW) rabbits, which are commonly used for toxicity tests, and to provide reference materials for pharmaceutical companies and research centers. A total of 586 NZW rabbits were randomly chosen without sex preference and were examined using ocular equipment, including a direct ophthalmoscope, an indirect ophthalmoscope, a slit-lamp biomicroscope, a focal illuminator, and a fundus camera. This study showed that the incidence rate of temporary cataracts, regarded as a change within normal variation, was 0.5% in the NZW rabbits. Regarding abnormal ophthalmic disease, blepharitis was the most commonly observed ocular disease. Other findings included cataract, conjunctivitis, choroidal hypoplasia, keratitis, corneal scarring, eyelid laceration, posterior synechiae, uveitis, dacryocystitis, and persistent pupillary membrane. In total, the incidence rate of ophthalmic diseases was 9.6%. Based on sex and age distributions, females had more ocular diseases than males, and rabbits were less susceptible to eye diseases as they got older. In this study, photographs were taken to document findings, such as normal fundus, normal variations, ophthalmic disease, and histopathologic examination.

A Case of oculocutaneous albinism in a Maltese.

A 4-month-old female maltese dog was admitted to Veterinary Medical Teaching Hospital of Seoul National University for evaluation of abnormal color of bilateral irises. This patient had the photophobia in the light and exhibited the complete absence of pigment resulting in white hair, pink muzzle, eyelids and foot-pads. Central zone of the irises were yellow in color influenced by tapetal reflex, and peripheral zone were pale blue. The iridal capillaries were transparented on the irises. Ophthalmoscopic examination revealed a yellow tapetal fundus but no pigment in the nontapetal fundus.