Extracapsular cataract extraction: an analysis of 240 operations in dogs

A total of 240 extracapsular cataract extractions were performed on 214 dogs at the University of Illinois between 1968 and 1980. Overall success of the surgery, defined as restoration of functional vision for at least 6 weeks after surgery, was 79%. The success rates, on the basis of various parameters, were compared with the following results. The greater the number of years experience each surgeon had, the greater the surgical success rate. In dogs in which a second eye was operated on, the overall success rate on the second eye was approximately 20% less than that for the study as a whole. There was a significant difference in success rates between surgery on congenital and juvenile cataracts when compared with surgery on diabetic and senile cataracts, the first being 15% higher than the second. The success rate was 18% less for lensectomy with concurrent iridectomy than for lensectomy without iridectomy. There was no significant difference in success rates among the 3 procedures for extracapsular extraction used in this study, nor among the various breeds studied. There was no significant difference in the success rate of surgeries on the left eye, compared with surgeries on the right eye.     

Evaluation of client perceptions concerning outcome of cataract surgery in dogs

OBJECTIVE: To compare client perception of outcome of phacoemulsification in dogs with information obtained from medical records. DESIGN: Retrospective cohort study. ANIMALS: 108 dogs (203 eyes) undergoing phacoemulsification from May 1999 through April 2004. PROCEDURE: Data obtained from medical records included signalment, presence of diabetes mellitus, cataract stage, whether surgery was unilateral or bilateral, intraocular lens (IOL) placement, and postoperative complications. Owners completed a survey concerning outcome of phacoemulsification in their dog. Survey responses from owners classified as satisfied or dissatisfied with the outcome of phacoemulsification on the basis of their willingness, in retrospect, to have the surgery performed again were compared. RESULTS: Data from medical records and survey responses were available for 108 dogs (203 eyes). Median follow-up was 3 months via medical record review and 12 months via owner survey responses. Most (81%) owners were satisfied with outcome. The most common reason for dissatisfaction was loss of vision after surgery; however, most dissatisfied owners did not return their dog for examinations. Owner perception of success was not associated with patient age, sex, presence of diabetes mellitus, cataract stage, or IOL placement in at least 1 eye but was associated with perceived improvement of their pet's vision and activity level. Dissatisfied owners were significantly more likely to report that explanation of risks and complications before surgery was inadequate. CONCLUSIONS AND CLINICAL RELEVANCE: Owner perception of outcome after phacoemulsification in dogs was highly favorable. However, surgical risks and the importance of postoperative examinations, particularly in dogs undergoing visual deterioration, must be conveyed to clients.     

Entropion correction in dogs and cats using a combination Hotz-Celsus and lateral eyelid wedge resection: results in 311 eyes

A novel surgical combination technique for the correction of lateral lower lid entropion in dogs and cats is described, involving a combination of Hotz-Celsus and lateral eyelid wedge resection procedures. The technique was used to treat 311 eyes with lower lid entropion: 269 canine (109 bilateral, 51 unilateral) and 42 feline (16 bilateral, 10 unilateral). The most common canine breeds were the Shar Pei, Rottweiler, Bull Mastiff and Labrador Retriever. Domestic cats made up the majority of feline cases. The overall success rate for a single surgical procedure to correct lower lid entropion with this technique was 94.2% per eye.     

Primary lens luxation in the Chinese Shar Pei: clinical and hereditary characteristics

A pedigree analysis of a family of 15 related Chinese Shar Peis was conducted. This pedigree analysis, including affected and nonaffected dams, sires and offspring, was compiled to document and characterize the occurrence, common clinical signs, and age of onset of primary lens luxation while suggesting a possible mode of inheritance in this breed. Of the five offspring from the mating of an affected dam to two unrelated affected males, 100% of offspring were affected with bilateral primary lens luxations. Of the four viable offspring from the mating of the same affected dam to an unrelated, unaffected male, two dogs (50%) were affected. The average age of onset of affected animals (seven) in this first generation was 4.9 years (range 3–6 years). The six dogs in the second generation of the same pedigree line were 2-years-old at examination with none of these animals affected at the time of this study. The most common presenting complaints were a unilateral change in ocular appearance (5 of 7 dogs) and subjective vision impairment (4 of 7 dogs). The most common clinical sign upon ophthalmic examination was iridodonesis (unilateral 4 of 7 dogs; bilateral 3 of 7 dogs) and the presence of an aphakic crescent (3 of 7 dogs). Gonioscopy and tonometry of severely affected eyes revealed a narrow or closed iridocorneal angle and ocular hypertension. This study suggests that primary lens luxation does occur in the Chinese Shar Pei, resembling the clinical condition (age of onset, clinical signs) previously described in the terrier breeds, the Border Collie, and the Tibetan Terrier. Application of the phenotypic findings in this study to a Mendelian genetic model of inheritance suggests that primary lens luxation in the Chinese Shar Pei is inherited as a simple autosomal recessive trait.     

Keratoprosthesis with retrocorneal fixation: preliminary results in dogs with corneal blindness

Objective To evaluate the use and complications of a penetrating keratoprosthesis implantation in the management of corneal opacification in dogs. Methods A retrospective clinical study describes the indications for the surgical technique utilized and the outcomes of this procedure in 20 eyes of 19 dogs with blindness of corneal origin. A successful surgical outcome was defined as a clear keratoprosthesis optic and improvement or restoration of functional vision over a follow‐up period ranging from at least 8 months to a maximum of 7 years. Results Eyes with total corneal opacification resulting from chronic superficial keratitis (n = 11), keratoconjunctivitis sicca (n = 5), endothelial dystrophy (n = 3) and chemical burn (n = 1) were treated by unilateral (n = 18) or bilateral (n = 1) full‐thickness implantation of a keratoprosthesis. Keratoprostheses were retained in 15 eyes (75%) which regained vision to the date of reporting. Among these eyes, six had uncomplicated postoperative course, five developed retroprosthetic membranes and four developed granulation tissue over the optic of the keratoprostheses. These complications were successfully removed surgically in the nine eyes. The five remaining eyes (25%) developed serious early postoperative complications, for which enucleation had to be performed. Conclusion In keratopathies in which the corneal opacification could not be treated by standard medical or surgical procedures, this keratoprosthesis appears to be promising to restore vision in chronic superficial keratitis and deep corneal dystrophy. It appears to have a poor prognosis in keratoconjunctivitis sicca in brachycephalic dogs. The post operative complications retro‐prosthetic membranes and granulomatous overgrowth could be treated well.     

Development of glaucoma after phacoemulsification for removal of cataracts in dogs: 22 cases (1987-1997)

OBJECTIVE: To determine factors contributing to glaucoma after lens extraction via phacoemulsification in dogs. DESIGN: Retrospective study. ANIMALS: 22 dogs (29 eyes) with glaucoma and 21 dogs (30 eyes) without glaucoma after phacoemulsification. PROCEDURE: Medical record review. RESULTS: Eyes at increased risk for glaucoma included those of Boston Terriers, those with uveal or retinal abnormalities before surgery, and those with intraoperative intraocular hemorrhage. Significant differences between groups were not detected for incidence of preoperative lens-induced uveitis, presence of an intraocular lens, or frequency of an acute postoperative increase in intraocular pressure. Glaucoma developed (mean +/- SD) 12.8+/-14.1 months (median, 10 months; range, 0.25 to 55 months) after surgery. Eighteen of 29 (62%) eyes with potential for vision after onset of glaucoma retained vision for a mean of 16.5+/-12.8 months (median, 10.8 months; range, 1.5 to 37 months) after glaucoma was diagnosed. Most of these eyes still had vision at the conclusion of the study period. CONCLUSIONS AND CLINICAL RELEVANCE: Risk factors identified by this study will aid in preoperative counseling of clients and refining selection criteria for candidates for phacoemulsification. Careful follow-up for the remainder of the dog's life after surgery may improve long-term success rates by permitting early intervention before intraocular pressure increases substantially and vision is irreversibly lost. Surgery for cataracts may still be worthwhile in dogs with increased risk of glaucoma, especially if elderly, because of the lengthy period to onset of glaucoma after surgery and the beneficial effects of treatment after glaucoma develops.     

Canine cataracts, diabetes mellitus and spontaneous lens capsule rupture: a retrospective study of 18 dogs

OBJECTIVE: To describe the clinical presentation and surgical outcome of diabetic canine patients with cataracts and preoperative spontaneous lens capsule rupture. ANIMALS STUDIED: A total of 20 dogs and 40 eyes were included in the retrospective evaluation. The patients' ages ranged from 5 to 14 years (mean 8.5 years). RESULTS: All dogs had clinical diabetes mellitus, with the duration since diagnosis ranging from 30 to 240 days (mean 123 days). Cataracts were bilateral and noted to have been present for 14-112 days (mean 39 days). Of the 40 eyes affected with cataracts, 30 had a spontaneous rupture of the lens capsule prior to surgery. The capsular rupture was diagnosed on clinical examination in 28/30 eyes and was noted intraoperatively in 2/30. The location of the capsular rupture was equatorial in 29/30 and posterior in 1/30 eyes. Surgery was performed in 38/40 eyes, with one case lost to follow-up without surgical intervention. Prior to surgery, routine diagnostic ophthalmic examination, ocular ultrasound, electroretinography, and systemic evaluation were performed in all dogs. Surgical procedures included phacoemulsification in 28/40 eyes, with IOL placement performed in 20/28 eyes. Intrascleral prosthesis placement or enucleation was performed in 8/40 and 2/40 eyes, respectively, due to a significantly reduced ERG or secondary glaucoma. CONCLUSIONS: The duration of clinical follow-up (19/20 dogs) ranged from 1 to 36 months (mean 12.9 months). All eyes that had cataract surgery with or without IOL placement were sighted at the time of the last follow-up examination. Spontaneous lens capsule rupture associated with diabetes mellitus, cataract and rapid lens intumescence occurs in the dog. Early surgical intervention, prior to secondary complications of glaucoma and loss of retinal function, is associated with a favorable outcome.     

Surgical treatment of lumbosacral foraminal stenosis using a lateral approach in twenty dogs with degenerative lumbosacral stenosis

Objectives— To describe clinical signs, magnetic resonance imaging (MRI) and surgical findings using a lateral approach to the lumbosacral intervertebral foramen and to evaluate clinical outcomes in dogs with or without concurrent dorsal decompression and annulectomy.
Study Design— Retrospective study.
Animals— Dogs (n=20) with degenerative lumbosacral stenosis (DLSS).
Methods— Medical records (2002–2006) of dogs that had lumbosacral lateral foraminotomy alone or in combination with dorsal decompression were reviewed. Degree of dysfunction was assessed separately for each pelvic limb; dogs with unilateral signs were included in group A, those with bilateral signs in group B. Retrieved data were: signalment, history, neurologic status on admission, 3 days, 6 weeks, and 6 months postoperatively, duration of clinical signs, results of MRI, surgical site(s), intraoperative findings, and outcome.
Results— Based on the clinical and MRI findings unilateral foraminotomy was performed in 8 dogs, bilateral foraminotomy in 1 dog, unilateral foraminotomy with concurrent dorsal decompression in 7 dogs, and bilateral foraminotomy with concomitant dorsal decompression in 4 dogs. Surgery confirmed the presence of foraminal stenosis in all dogs, with osteophyte formation and soft tissue proliferations being the most common lesions. Outcome was good to excellent in 19 dogs and poor in 1 dog. Mean follow-up was 15.2 months (range, 6–42 months).
Conclusion— Lateral foraminotomy addresses compressive lesions within exit and middle zones of the lumbosacral foramen.
Clinical Relevance— Successful surgical management of DLSS is dependent on recognition and correction of each of the compressive lesions within the lumbosacral junction.     

Effects of topical administration of an aldose reductase inhibitor on cataract formation in dogs fed a diet high in galactose

OBJECTIVE: To determine effects of a topical formulation of an aldose reductase inhibitor (ARI) on the development of sugar cataracts in dogs fed a diet high in galactose. Animals-Ten 6-month old Beagles. PROCEDURES: Dogs were fed a diet containing 30% galactose, and after 16 weeks, 6 dogs were treated topically with a proprietary ARI formulation and 4 dogs were treated with a placebo. Cataract formation was monitored by means of slit-lamp biomicroscopy and fundus photography. Dogs were euthanized after 10 weeks of treatment, and lenses were evaluated for degree of opacity, myo-inositol and galactitol concentrations, and concentration of the ARI. RESULTS: All dogs developed bilateral cortical opacities dense enough to result in a decrease in the tapetal reflex after being fed the galactose-containing diet for 16 weeks. Administration of the ARI arrested further development of cataract formation. In contrast, cataracts in the vehicle-treated dogs progressed over the 10-week period to the mature stage. Evaluation of the isolated lenses after 26 weeks of galactose feeding indicated that lenses from treated dogs were significantly less optically dense than lenses from control dogs. Lenticular myo-inositol concentration was significantly higher in the treated than in the control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that topical application of a proprietary ARI formulation may arrest or reverse the development of sugar cataracts in dogs fed a diet high in galactose. This suggests that this ARI formulation may be beneficial in maintaining or improving functional vision in diabetic dogs with early lens opacities.     

Clinical features and outcomes of phacoemulsification in 39 horses: a retrospective study (1993-2003)

OBJECTIVE: To identify visual outcome and postoperative complications following phacoemulsification of equine cataracts. ANIMALS: Records of 39 horses (55 eyes) with cataracts were reviewed. METHODS: Eyes with cataracts removed by phacoemulsification were included in the study. Data collected included age, breed, sex, stage and etiology of cataract, unilateral vs. bilateral involvement, and ultrasound findings. Horses were grouped by etiology of the cataract. Visual outcome and complications were evaluated for each group and the overall population. RESULTS: Immediately postoperatively 46 out of 47 eyes (98%) were sighted. Four weeks postoperatively 23 of 29 operated eyes (79%) were sighted [13/18 (72%) eyes with congenital/juvenile onset, 6/6 (100%) eyes with traumatic and 4/5 (90%) eyes with uveitis-induced cataracts], with 18 eyes lost to follow-up. The most common postoperative complications included corneal edema (19 eyes/40%), fibrin in the anterior chamber (11 eyes/23%), postoperative ocular hypertension (9 eyes/19%), synechia/dyscoria (9 eyes/19%), and hyphema (7 eyes/15%). CONCLUSIONS: Prognosis for vision is favorable for horses following phacoemulsification and planned posterior continuous tear circular capsulorrhexis. Success rates depend on age of patient, cause of cataract and pre-existing intraocular disease. The highest success rate occurred in eyes with traumatic cataracts.     

Parotid duct transposition in dogs: a retrospective review of 92 eyes from 1999 to 2009

Objective The aim of this study was to perform a retrospective review of parotid duct transposition (PDT) in the dog to determine the rate and nature of complications, the success and failure rates and to evaluate owner satisfaction. Methods Medical records of 56 dogs (92 eyes) that underwent PDT and subsequent follow‐up by a veterinary ophthalmologist were reviewed. Forty owners (40 dogs/66 eyes) were contacted by telephone and 37 owners (37 dogs/60 eyes) also completed a visual analog scale questionnaire. Statistical evaluation included Wilcoxon Signed Rank tests, one‐way analysis of variance and Kaplan–Meier survival analysis with Wilcoxon and Log‐rank tests. Results The mean follow‐up was 38.7 months (range 1–109 months). The surgical success rate was 92% (85/92 eyes). Total failures (8%, 7/92 eyes) were because of severe saliva intolerance (n = 5 eyes) and PDT failure (n = 2 eyes). The complication rate was 50% (46/92 eyes) of which 61% (28/46 eyes) were managed medically and 39% (18/46 eyes) required further surgery. Ninety percent (36/40) of owners indicated that they would proceed with surgery again. Statistically significant improvements in owner perception of ocular comfort, number of daily topical treatments, ocular wetness, and postoperative vision were identified. Conclusions This study shows that PDT is a successful procedure based on clinical findings and in terms of owner perception. It has also demonstrated that PDT improves ocular comfort and vision in medically refractive cases of keratoconjunctivitis sicca, and that a low level of on‐going management is required in 33% of cases.     

Intracapsular lensectomy and sulcus intraocular lens fixation in dogs with primary lens luxation or subluxation

Objective  To evaluate the postoperative results of lensectomy and sulcus intraocular lens fixation (SIOLF) via an ab interno approach in dogs with progressive lens subluxation or early luxation.
Study design  Retrospective study.
Animals studied  Twenty eyes from 19 dogs presented to the Animal Eye Clinic for lens luxation or subluxation between 1999 and 2006.
Methods  Medical records were reviewed to evaluate preoperative lens position, vision status, intraocular pressure (IOP), and whether surgery was performed on an emergent or elective nature. Lensectomy and SIOLF were performed and postoperative status including vision, glaucoma, and retinal detachment was assessed.
Results  Average age was 8.6 years (range 4–14 years) and 55% (11/20) were terriers. Patients were followed a mean of 29.2 months (range 1–92 months) after surgery. Retinal detachment or secondary glaucoma was observed in 1 of 20 (5%) and 5 of 20 (20%) eyes, respectively, with 1 of 20 (5%) exhibiting both. Mean preoperative IOP was 16 mmHg and preoperative lens position was equally divided between luxated and subluxated lenses. Surgery was performed more frequently as an elective procedure (18/20; 90%) due to normalized IOP vs. an emergency procedure (2/20; 10%). Vision was retained in 70% (14/20) of eyes with a mean time to vision loss of 41 months in the remaining eyes due to glaucoma, retinal detachment, or retinal degeneration.
Conclusions  Complications of glaucoma and retinal detachment after SIOLF in this study were less when compared with previously reported incidence rates in the literature for lensectomy alone which may reflect improved patient selection.     

Cataracts in 44 dogs (77 eyes): A comparison of outcomes for no treatment, topical medical management, or phacoemulsification with intraocular lens implantation

Outcomes for 77 cataractous eyes were compared after each eye underwent no treatment, topical medical treatment only, or phacoemulsification with intraocular lens implantation. Median follow-up time for all dogs was 2.3 y. Failure occurred in all untreated eyes and the rate of failure was 65 and 255 times higher than in medically and surgically treated eyes, respectively. The failure rate was 4 times higher in dogs receiving only medical treatment compared with dogs that received surgery. Across all groups, the success rate for mature and hypermature cataracts was lower than for immature cataracts. Regardless of cataract stage, the chance of success was higher for eyes undergoing phacoemulsification than for eyes that received medical management only. Results of this study support prompt referral for phacoemulsification when cataracts are diagnosed in dogs or, if referral is not possible, topical anti-inflammatory therapy.     

犬乳腺肿瘤手术治疗及其预后的调查

本研究采用单个乳腺切除、区域乳腺切除、单侧乳腺切除对临床31例犬乳腺肿瘤病例进行手术治疗,调查不同手术方法及肿瘤质量对良性、恶性乳腺肿瘤术后预后的影响。结果显示,犬乳腺肿瘤的大小与其预后相关,随着犬瘤体质重的增加,其术后预后不良愈加明显,复发率、死亡率呈上升趋势;区域乳腺摘除术或乳腺完全根除术对乳腺肿瘤患犬的预后有一定影响。     

Treatment of glaucoma by use of transscleral neodymium:yttrium aluminum garnet laser cyclocoagulation in dogs

Neodymium:yttrium aluminum garnet (Nd:YAG) laser energy was transsclerally applied to the ciliary body of 56 eyes of 37 dogs for treatment of glaucoma. Forty-four eyes were glucomatous at the time of treatment, and 12 normotensive eyes with ciliary cleft closure were treated prophylactically. Glaucoma was primary in 35 dogs and secondary in 2 dogs (1 eye in each dog). Energy was delivered by a general surgical Nd:YAG laser via a hand-held, 600-muc-diameter flexible quartz fiber. The mean (+/- SD) number of spots treated per eye was 35 (+/- 9.7), with mean energy per burst of 7.1 (+/- 2.6) J; mean total energy delivered to the eyes was 228 (+/- 81) J. Follow-up evaluation was available for 42 eyes from 2 to 4 weeks after treatment, and for 32 eyes from 12 to 24 weeks after treatment. Treatment success, defined as maintenance of intraocular pressure less than 25 mm of Hg, was achieved in 83% (20/24) of glaucomatous eyes evaluated between 12 and 24 weeks of treatment. Of 4 treatment failures, 3 were eyes devoid of uveal pigment. The consistent acute effects of treatment were conjunctival vascular congestion and blood-aqueous barrier disruption, recognized clinically by the presence of aqueous flare. Hyphema developed in 16% (9/56) of eyes; hyphema resolved without complication in all but 2 eyes. A common long-term complication of treatment was cataract formation, recognized in 37% (12/32) of eyes evaluated at 12 to 24 weeks. Cataracts were sufficiently dense to obstruct vision in 4 eyes. Phthisis bulbi was observed in 1 eye.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cataracts in Labrador Retriever and Jack Russell Terrier From the United Kingdom: A Two-Year Retrospective Study

Cataracts are among the most common ocular diseases, and are a leading cause of vision loss in humans and dogs. Jack Russell Terriers (JRT) and Labrador Retrievers (LR) are among the most popular canine breeds in the United Kingdom, and also among the most affected by cataracts.This study aimed to analyze the clinical features and the surgical outcome of cataracts in JRT and LR in an ophthalmologic reference Veterinary Hospital in the United Kingdom. For that purpose, medical records from JRT and LR diagnosed with cataracts between January 2015 and December 2016 were retrospectively evaluated. Data related to identification, clinical history, preoperative features, and surgical outcomes were analyzed.Forty-four dogs (81 eyes), including 26 JRT and 18 LR, were enrolled in the study. Mean ages were 10.2 ± 3.2 years in JRT and 8.5 ± 3.7 years in LR. Twenty-eight (63.6%) were females and 16 (36.4%) were males. Most dogs (84.1%) presented with bilateral cataracts. Nuclear and cortical cataracts were the most prevalent type in both breeds (JRT: n?=?30, 61.2%; LR: n?=?16, 50.0%), although subcapsular cataracts were also frequent in LR (n?=?10, 31.3%). Significant differences in cataract location within the lens were detected between the two breeds (P?=?.002).Senile in JRT (n?=?7) and genetic in LR (n?=?7) were the most common etiologies. Concomitant ocular lesions were more frequent in dogs presented with cataracts in advanced stages, and included lens (n?=?18; JRT: n?=?15; LR: n?=?3) and retinal alterations (n?=?8; JRT: n?=?2; LR: n?=?6), and glaucoma (n?=?6; JRT: n?=?5; LR: n?=?1). Thirty-three animals (75.0%, 51 eyes) were submitted to phacoemulsification with intraocular lens placement. Of these, 28 eyes (54.9%; JRT: n?=?21; LR: n?=?7) were visual, 19 eyes (37.3%; JRT: n?=?11; LR: n?=?8) presented impaired vision and four eyes (7.8%; JRT: n?=?0; LR: n?=?4) were blind at last clinical record. Postoperative complications were detected in 11 eyes (21.6%), and were more frequent in dogs presented with cataracts in advanced stages.These results and the multifactorial nature of cataracts call for further studies to identify and characterize the variables in a broader assessment, including other breeds and influencing factors.     

Urinary Incontinence after Surgical Repair of Ureteral Ectopia in Dogs

Eleven of 20 dogs (55%) were incontinent after surgical treatment of ureteral ectopia. Ureterocystostomy was performed in 15 dogs, ureteral transection and bladder reimplantation in four dogs, and ureteronephrectomy in one dog. Siberian huskies had a significantly higher rate of persistent postoperative incontinence than other breeds. There was no difference in postoperative incontinence between dogs with unilateral and bilateral ectopia. Concurrent bacterial cystitis was not associated with persistent postoperative incontinence. Age at the time of surgical correction had no effect on the rate of postoperative incontinence. Eight incontinent dogs were treated medically; three are continent with medication, three are improved but still incontinent, and two did not improve.     

Cataract surgery with foldable intraocular lens implants in captive lowland gorillas (Gorilla gorilla gorilla).

Two juvenile, male, captive-born lowland gorillas (Gorilla gorilla gorilla) with the same father but different mothers developed bilateral cataracts. The cataracts were surgically removed within 6 yr and 3 mo, respectively, of diagnosis, and foldable intraocular lenses were implanted. Although vision was not restored in one eye with a mature, 6-yr-old cataract in gorilla A, surgical intervention on the other eye was performed before a complete cataract developed, and vision was fully restored. Gorilla B was treated at the age of 17 mo, and normal visual development proceeded in both eyes. This animal developed bilateral after-cataract and therefore needed a second intervention in both eyes using Nd:YAG laser treatment. The genetic component of juvenile cataracts should be considered in breeding management programs.     

Lens-induced uveitis in dogs: 151 cases (1985-1990).

During a 5-year period, phacolytic uveitis was diagnosed in 202 eyes of 151 dogs admitted to the veterinary teaching hospital. The diagnosis of phacolytic uveitis was based on the finding of a cataractous lens and anterior uveitis, unassociated with other identifiable causes of uveal inflammation. The most commonly affected breeds were the Toy and Miniature Poodle (35%) and the American Cocker Spaniel (19%). The mean age was 7.0 years for all breeds, 5.1 years for the Cocker Spaniel, and 9.0 years for the Poodle breeds. Evidence of cataract resorption was visible in 72% of the eyes. Fifty-one dogs were affected bilaterally and 100 dogs unilaterally. The mean interval between recognition of the cataract and the onset of lens-induced uveitis (LIU) was 17 months; mean times of 25 and 11 months were seen in the Poodle breeds and American Cocker Spaniel, respectively. The mean age of dogs requiring greater than 1 revisit before the inflammation had subsided was 5.5 years. Complications, referable to the uveitis, were seen in 14% of eyes, the most important of which were glaucoma (16 eyes) and phthisis bulbi (9 eyes). Lens extraction surgery was done on 50 LIU-affected eyes, and on 35 normal eyes in LIU-affected animals. The 2- and 6-month success rates for LIU-affected eyes were 78 and 39%, respectively, and for normal eyes in LIU-affected animals were 85 and 71%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effects of cataract stage, lens-induced uveitis and cataract removal on ERG in dogs with cataract

OBJECTIVE: The purpose of this study was to determine the effects of cataract stage, lens-induced uveitis and cataract removal on the electroretinogram (ERG) of dogs with cataract. ANIMALS STUDIED: Fifty-seven dogs diagnosed with unilateral or bilateral cataract whose ERG was recorded at Rakuno Gakuen University Teaching Animal Hospital from 2001 to 2004. PROCEDURES: Four responses were recorded during the ERG: rod ERG, standard combined ERG, single-flash cone ERG and 30-Hz flicker ERG. Cataracts were divided into four stages: incipient, immature, mature and hypermature, and with or without lens induced uveitis (LIU). Noncataractous eyes of dogs with unilateral cataract were used as the control. We compared ERG amplitude, implicit time, and the b- to a-wave amplitude ratio of cataractous vs. noncataractous eyes, preoperative vs. postoperative cataractous eyes, and cataractous eyes with and without LIU. RESULTS: No significant difference was found in ERG amplitude between incipient, immature and hypermature cataractous eyes, while in mature cataractous eyes decreased amplitude was confirmed in all responses compared with control eyes. However, no significant difference in b/a ratio was found at any stage of cataract. In postoperative eyes, increased amplitude was recorded in all responses compared to preoperative values. In eyes with LIU a decreased amplitude in the rod ERG and b-wave of standard combined ERG was recorded and, furthermore, a significant decline was confirmed in b/a ratio. CONCLUSION: ERG values were influenced by cataract stage and LIU. LIU was associated with a reduction in the b/a ratio.