Search

Objective: To identify ocular and adnexal diseases to which llamas in North America are susceptible, to determine prevalence of these diseases in llamas, and to compare prevalences of the major ocular diseases of llamas, cattle, and horses., Design: Retrospective study., Animals: 194 llamas, 4,937 cows, and 11,950 horses with ocular disease., Procedure: Medical records of all llamas entered into the Veterinary Medical Database between 1980 and 1993 were reviewed. Data on ocular structures affected and types of ocular disease were compiled. Prevalences of uveitis, corneal ulcers, and ocular squamous cell carcinoma in llamas were compared with prevalences in cattle and horses., Results: 194 of 3,243 (6%) llamas had at least 1 ocular disease. The proportion of llamas that had ocular disease was significantly higher than the proportions of cattle or horses. The most frequently affected ocular structure in llamas was the cornea, and ulcerative keratitis was the most common corneal disease. The second most commonly affected structure was the uveal tract. Cataracts were reported in 20 (10%) of the llamas with ocular problems. Eyelid disorders, retinal diseases, glaucoma, and ocular or adnexal neoplasia were reported infrequently in llamas., Clinical Implications: Results suggest that corneal disease is common in llamas and is usually secondary to trauma. Uveitis may also be common in llamas, but llamas do not appear to be highly susceptible to glaucoma, ocular neoplasia, or to direct corneal invasion by bacteria such as Moraxella sp.

Equine recurrent uveitis is an important ocular disease and the most common cause for blindness in horses and mules worldwide. The anatomy, physiology, immunology and inflammatory reactions of the uveal tract are discussed. Possible etiologies and the clinical signs are described. A detailed description of possible therapies is given and the prognosis is discussed.

Particular immunopathological features and their effects on the vascular permeability of different ocular structures were analysed in two dogs naturally infected by Leishmania infantum. The existence of specific anti-Leishmania immunoglobulin G (IgG) in the aqueous humour was confirmed by the ELISA technique. There was no correlation between antibody levels in the aqueous humour and the related serum. The histopathological study of the eyes showed the existence of lesions in various ocular structures. The ciliary processes, ciliary body, sclerocorneal limbus, iris and lacrimal duct showed intense inflammatory zones with lymphocyte infiltrates, plasmatic cells and macrophages with amastigote forms of Leishmania. In addition vasculitis with dilation and thrombi were also detected in both cases, with consequent oedema and hyalinization. The immunohistochemistry analysis revealed the presence of granular and diffuse IgG deposits in the ciliary body, ciliary processes, sclerocorneal limbus and iris. Furthermore, numerous thrombosed vessels were observed in the sclerocorneal zone and iris. Complement 3 (C3) fraction deposits were not present in the ocular structures. The present data suggest that the ocular lesions may have an immunopathological origin.

Objectives: To develop Toxoplasma gondii B1 gene polymerase chain reaction (PCR) for use with aqueous humor of cats, and to report PCR and antibody detection results in naturally exposed cats with and without uveitis., Sample Population: Serum and aqueous humor samples from client-owned, healthy cats (n = 23) and client-owned cats with uveitis (n = 43)., Procedure: T gondii-specific IgM and IgG were measured in serum and aqueous humor from all cats. The Goldman-Witmer coefficient for ocular antibody production was calculated for cats positive for T gondii-specific IgM or IgG in aqueous humor. Aqueous humor from all cats was assessed by the B1 gene PCR., Results: T gondii was detected in aqueous humor by PCR from 2 of 23 (8.7%) healthy cats and 8 of 43 (18.6%) cats with uveitis. T gondii-specific IgM in either serum or aqueous humor was detected in 5 of 8 (62.5%) cats with uveitis and T gondii in aqueous humor. All cats with uveitis and T gondii in aqueous humor had anterior segment disease. In 5 of 8 (62.5%) cats with uveitis and T gondii in aqueous humor, ocular production of T gondii antibodies was not detected. T gondii was not detected in aqueous humor from 14 of 17 (82.4%) cats with ocular production of T gondii-specific antibody., Conclusions: The presence of T gondii in aqueous humor may correlate to clinical disease in some, but not all, cats., Clinical Relevance: T gondii-specific aqueous humor antibody tests and PCR should be used together to aid in the diagnosis of ocular toxoplasmosis in cats.

In Germany very little is known about antibody titers against Borrelia burgdorferi in the horse. In the USA there exist some studies on the titer levels and symptoms due to borrelia infections. Beside lameness, fever, polyarthritis, pneumonia and dullness there is a study showing a connection between panuveitis and Borrelia infection in the horse. In human medicine the infection with Borrelia burgdorferi becomes more and more important. Uveitis and other eye diseases due to Borrelia burgdorferi are proved and documented. The goal of this study was to find a connection between antibodies to Borrelia burgdorferi and cases of equine recurrent uveitis (ERU). The antibody titer against Borrelia burgdorferi was determined by IFT in 153 horses with no sign of disease of the eye and in 79 horses with equine recurrent uveitis (ERU). 48% of all horses were found to be positive (titer 1:64 or higher). In addition 22 sera were tested in western-blot for antibody titers. There was no significant correlation between signs of ERU and increased antibody titers against Borrelia burgdorferi (p > 0.05). No clinical signs were seen in horses with elevated titers. No correlation between the age of the horses and the antibody level could be found. There was a connection between the antibody titer and the month of examination (p < 0.05). Highest titer levels were seen in May and November. This is both one month later than the activity of the transmitting ticks (I. ricinus).

One of the authors (D. L. W.) visited ophthalmologists in Great Britain, Europe and the USA to assess current practice in the surgery of cataracts in dogs. This paper describes the results of these visits and provides a survey of the literature. The success rates in canine cataract surgery have increased markedly in the last 10 years, particularly as a result of the introduction of phacoemulsification techniques and the reduction in the use of extracapsular cataract extraction; these new techniques and the problems they seek to overcome are discussed. The paper also considers the developing field of intraocular lens implantation, the rationale behind such developments and the benefits and potential problems which may occur after the extraction of a cataract and the implantation of a lens.

Uveitis is a commonly misdiagnosed ophthalmic condition with a wide aetiological base and often the cause cannot be established. Uveitis can be associated with systemic diseases like feline infectious peritonitis, feline immunodeficiency virus, feline leukaemia virus, lymphoma, toxoplasmosis and canine ehrlichiosis. The classification and general clinical signs of uveitis are discussed. Applicable clinical cases, manifestations and diagnostic methods of the selected diseases are mentioned, and a general approach to the treatment of uveitis is given.

Recurrent uveitis, a leading cause of blindness in horses, often develops as a sequela to systemic leptospirosis. Over a 7-year period, 63 of 112 (56%) horses with uveitis were seropositive for Leptospira interrogans serovar pomona, but only 23 of 260 (9%) horses without uveitis were seropositive. Odds-ratio analysis revealed that seropositive horses were 13.2 times more likely to have uveitis than were seronegative horses. Of the 63 seropositive horses with uveitis, 59% developed blindness, compared with only 24% in the 49 seronegative horses with uveitis that lost vision in 1 or both eyes during the same period. Odds-ratio analysis revealed that seropositive horses with uveitis were 4.4 times more likely to lose vision than were seronegative horses with uveitis. Of the 112 horses with uveitis, 28 (25%) were Appaloosas, compared with only 10 of the 260 (4%) horses without uveitis (odds ratio, 8.3). In addition, 19 of the 28 (68%) Appaloosas with uveitis developed blindness, compared with only 30 of the 84 (36%) non-Appaloosas with uveitis that lost vision in 1 or both eyes (odds ratio, 3.8). This field study therefore confirmed a strong positive relationship between uveitis and leptospiral seroreactivity in horses. Furthermore, the data suggested that seropositive horses with uveitis were at increased risk of losing vision, compared with that in seronegative horses with uveitis, and that Appaloosas were at increased risk of developing uveitis and associated blindness, compared with that in non-Appaloosas.

Ocular contents from a horse with a 4-week history of severe unilateral uveitis were submitted for histopathologic examination. A severe unilateral granulomatous chorioretinitis with intralesional Halicephalobus deletrix was diagnosed. The horse developed progressive neurologic signs several days following the surgery to remove ocular contents and implant a prosthesis and was subsequently euthanatized. A severe multifocal granulomatous encephalitis with intralesional H. deletrix, localized primarily to the optic chiasm, thalamus, and brain stem, was diagnosed from tissues acquired at necropsy. The other eye was not affected. This is the first report of ocular parasitism by H. deletrix and suggests possible systemic dissemination from a primary site in the eye.

Intraocular production of Toxoplasma gondii-specific antibody in cats has been estimated by comparing the ratio of T gondii-specific antibody in aqueous humor and serum with the ratio of total immunoglobulins in serum and aqueous humor (Goldmann-Witmer coefficient; aqueous antibody coefficient; C value). It has been proposed that in human beings, comparison of the ratio of T gondii-specific antibody in aqueous humor and serum with the ratio of antibodies against a nonocular pathogen in serum and aqueous humor is more accurate than methods using total immunoglobulin quantification. We developed an ELISA for detection of calicivirus-specific antibodies in the serum and aqueous humor of cats. By evaluating calicivirus-specific antibody concentrations in the aqueous humor of healthy and diseased cats, calicivirus was assessed as a nonintraocular pathogen. The ratio of T gondii-specific antibodies in the aqueous humor and serum and the ratio of calicivirus-specific antibodies in serum and aqueous humor were evaluated as a means of estimating intraocular T gondii-specific antibody production. A field strain of feline calicivirus was isolated, cultured, and purified. A calicivirus-specific IgG ELISA was developed for detection of feline calicivirus-specific IgG in serum and aqueous humor. Calicivirus-specific IgG was measured in the serum and aqueous humor from 3 groups of control cats. Results suggested that calicivirus is a nonintraocular pathogen in cats and that calicivirus IgG detected in aqueous humor is attributable to leakage across a damaged blood-ocular barrier.(ABSTRACT TRUNCATED AT 250 WORDS)

Topical cyclosporine A was safely used in a series of 11 cases of equine keratitis and keratouveitis and appeared to be an effective anti-inflammatory agent in 9 cases. The clinical diagnoses included interstitial keratouveitis, endotheliitis, multifocal punctate keratopathy and a melting stromal ulcer. In most cases, the presence or absence of insidious bacterial infection was not conclusively determined. Topical cyclosporine A had no deleterious effects in this series of cases. The authors suggest that topical cyclosporine in both aqueous and lipid base vehicles should be investigated and evaluated as an alternative mode of achieving ocular immunosuppression.

Congenital defects of the lens are rare in the cat. In this report, two unrelated Siamese kittens, a four-month-old male and a six-month-old female, with microphakia are presented. Abnormally small lenses were associated with elongation and rupture of the ciliary processes, leading to lens subluxations and subsequent anterior luxations. To the authors' knowledge, this condition has been reported only once previously.

The blood-aqueous barrier in dogs is compromised by uveitis, surgery, and limbal paracentesis. Breakdown of the blood-aqueous barrier allows protein into the aqueous humor and results in mild to severe inflammation. Diagnosis of protein in the aqueous humor is traditionally a subjective measurement. Laser flaremetry was used for noninvasive quantitation of aqueous humor protein concentration in dogs. Flaremetry data were compared with aqueous humor protein concentrations obtained from aqueous humor paracentesis and slit-lamp flare evaluations. Results from clinically normal eyes and those with uveitis and cataracts were compared. Subjective evaluations of flare were correlated with a range of flaremetry readings and aqueous humor protein concentrations. Clinically normal eyes had a range of flaremetry readings of 1.4 to 7.0 photon counts (PC)/ms, with a mean of 3.8 PC/ms. Corresponding aqueous humor protein concentrations ranged from 5 to 28 mg/dl, with a mean of 15.1 mg/dl. Eyes with uveitis or cataracts had a range of aqueous protein concentrations of 13 to 729 mg/dl. Flaremetry readings accurately and sensitively measured total protein concentrations in the aqueous humor of dogs.

Bilateral uveitis and multiple xanthomas (fat deposits in the skin) are described in a 3.5-year-old ovariohysterectomized female Persian cat. The cat had been treated for 2 years with corticosteroids. Examinations included a routine blood chemistry profile, radiographic examination of the thorax and abdomen, histopathological examination of multiple skin punch biopsies, and analysis of blood lipid components by cellulose-acetate electrophoresis and by preparative ultracentrifugation studies. Total lipid values were 23 g/l. Ultracentrifugation studies indicated strongly elevated VLDL and LDL fractions and a decreased concentration of the HDL fraction. Because of sudden blindness the cat was euthanized at the request of the owner. Autopsy revealed massive atherosclerotic changes in the large abdominal vessels, the wall of the aorta, and the coronary vessels. Although the exact pathogenesis remains uncertain, these unusual findings might be explained by a primary hyperlipoproteinaemia, complicated by long-term use of corticosteroids.

Data were collected from the medical records of 123 nondiabetic dogs (182 eyes) and 30 diabetic dogs (57 eyes) in which phacoemulsification surgery was performed. Pre- and postoperative comparisons, including signalment, initial ophthalmic examination findings, surgical variables, and postoperative findings for the short-term follow-up period (mean, 5.75 weeks), between nondiabetic and diabetic dogs revealed that the complication rate was not greater in the diabetic group. Postoperative uveitis was evident with nearly equal frequency (in nondiabetic dogs, 90% or 164 of 182 eyes and in diabetic dogs, 88% or 50 of 57 eyes). In nondiabetic dogs, 1% prednisolone ophthalmic solution and prednisone were administered pre- and postoperatively, and amoxicillin and dichlorphenamide postoperatively. In diabetic dogs, the same treatment regimen, except for treatment with flunixin meglumine IV at surgery and substitution of aspirin for prednisone, was used. When nondiabetic and diabetic dogs were treated according to their respective pre- and postoperative medical regimens, clinical differences in postoperative findings were not apparent.

The lens-induced uveitis is a diagnostic as well as a therapeutic challenge for the veterinarian. In most cases the ocular structures have already been irreversibly damaged, so that the therapy can only bring relief, but does not lead to full recovery. This is a review of the pathophysiology and the resulting diagnostic consequences of the lens-induced uveitis. One case is discussed and recommendation for medical treatment is given.

Significant allergic- and immunologic-mediated diseases of the eye are reviewed. Included are diseases of the lacrimal gland namely keratoconjunctivitis sicca, immune-mediated diseases of the conjunctiva, atopic blepharoconjunctivitis, and marginal blepharitis, uveitis including lens-induced uveitis, episcleritis, orbital cellulitis, and optic neuritis. Significant diagnostic features, an approach to diagnostic workup, and treatment are presented.

Equine clinical leptospirosis has been primarily related to uveitis and the often recurrent sequelae of ocular changes. Reports of equine hepatic and renal involvement are sporadic. More recently, serovar bratislava has been identified as a host-adapted serovar in the horse. More significantly, reports of equine abortion and stillbirth have become more frequent in the literature. This is more than likely a result of improved diagnostic techniques, not of increased prevalence of disease. In addition to abortion, equine neonatal disease is becoming more frequently recognized in association with leptospira infection. Whether leptospiral infection results in abortion or diseased foals may depend upon the stage of gestation when the mare is exposed and host immune status. Antibiotic of choice for treatment of equine leptospirosis remains speculative, as specific equine studies have not been performed. Extrapolation from other species suggests that the use of streptomycin remains a good choice of therapy for the chronic shedding state and may be used in combination with other antimicrobials for treatment of acute disease. Penicillin or potentiated penicillins and tetracycline at appropriate to high end dosages are logical choices for the treatment of acute leptospirosis.

There is no direct verification of pineal gland involvement in human uveitis. Specimens of pineal tissue are not available during active uveitis in human patients. Naturally occurring uveitis in horses gives us an opportunity to examine tissues during active ocular inflammation. We examined the pineal gland of a horse that was killed because it had become blind during an episode of uveitis. The clinical history and histopathology of the eyes were consistent with post-leptospiral equine recurrent uveitis. The pineal gland of this horse had significant inflammatory infiltration consisting mainly of lymphocytes with some eosinophils. This observation of pinealitis accompanying equine uveitis supports the animal models of experimental autoimmune uveoretinitis with associated pinealitis and suggests that the pineal gland may be involved in some human uveitides.

Uveitis (inflammation of the iris, ciliary body, or choroid) is a potentially blinding condition with a significant economic impact on the horse industry. Variable symptoms are described, as well as a considerable range of structural and functional sequelae. Known causes of initial episodes include bacterial, viral, traumatic, and parasitic insults, with recurrence by immunologic mechanisms. Treatment strategies and management recommendations that may reduce the incidence or severity of episodes are discussed.

A review of the literature pertaining to the uveodermatological syndrome of dogs is presented. This syndrome is marked by depigmentation of the periocular region, lips and nose in association with severe uveitis. Early diagnosis and therapy can prevent serious vision loss. Symptoms and therapy of the cases described in the literature as well as cases seen at the Veterinary Medical Teaching Hospital in Davis/California are discussed.

Serologic evidence of infection by Toxoplasma gondii, feline leukemia virus, feline coronaviruses, or feline immunodeficiency virus (FIV) is commonly found in cats with uveitis. Serum samples from 124 cats with uveitis were assayed by use of ELISA for the detection of T gondii-specific immunoglobulin M (IgM), IgG, and circulating antigens (Ag), as well as an ELISA for feline leukemia virus Ag, an ELISA for antibodies to FIV, and an indirect fluorescent antibody assay for antibodies to feline coronaviruses. Serologic evidence of infection by 1 or more of the infectious agents was detected in 83.1% of the samples. Serologic evidence of T gondii infection, defined as the detection of T gondii-specific IgM, IgG, or Ag in serum, was found in 74.2% of the samples. The seroprevalence of T gondii infection was significantly greater in cats with uveitis than in healthy cats from a similar geographic area. Serum samples from cats with serologic evidence of both T gondii and FIV infections were more likely to contain T gondii-specific IgM without IgG than samples from cats with serologic evidence of T gondii infection alone. Cats with serologic evidence of FIV and T gondii coinfection had a higher T gondii-specific IgM titer geometric mean and a lower T gondii-specific IgG titer geometric mean than did cats with serologic evidence of T gondii infection alone. Serologic evaluation for T gondii infection should include assays that detect IgM, IgG, and Ag, particularly in cats coinfected with FIV.

Serum and aqueous humor samples, collected from 14 clinically normal cats and 96 cats with clinical evidence of intraocular inflammation, were assayed with ELISA for Toxoplasma gondii-specific immunoglobulin M (IgM), T gondii-specific IgG, T gondii-specific antigens, total IgG, and total IgM. Additionally, serum was assayed with ELISA for feline leukemia virus p27 antigen and antibodies against the feline immunodeficiency virus as well as with an immunofluorescent antibody assay for antibodies against feline coronaviruses. Calculation of the Goldmann-Witmer coefficient (C-value) for the T gondii-specific antibodies detected in aqueous humor established the likelihood of local antibody production. Serologic evidence of present or prior infection by an infectious agent was found in 81.9% of the clinically affected cats from which serologic results were available (77/94 cats). Seropositive results for toxoplasmosis were found in 74.0% of the clinically affected cats. Anterior segment inflammation was found in 93.1% (81/87 cats from which information was available) of the clinically affected cats, most of which were older males. Toxoplasma gondii-specific antibodies were not detected in the aqueous humor of 6 seropositive, clinically normal cats. The C-values for aqueous T gondii antibodies were greater than 1 in 44.8% of the cats and greater than 8 in 24.0% of the cats. Response to treatment with clindamycin HCl was positive in 15/20 (75%) of the T gondii-seropositive, clinically affected cats treated with this drug. In 13/15 (86.7%) T gondii-seropositive, clinically affected cats having a C-value greater than 1, response to treatment with clindamycin HCl was positive.(ABSTRACT TRUNCATED AT 250 WORDS)

C3 was detected bound in vivo to the opaque cornea of horses inoculated with killed Leptospira interrogans. Employing epithelial corneal cells isolated from a monolayer in tissue culture, we proved that C3 is fixed in vitro to the intact cell surface after incubation with a fresh equine anti-Leptospira serum. These findings, in addition to the infiltration of cornea with neutrophils and lymphocytes, may explain the mechanisms of tissue damage in recurrent uveitis of horses with leptospirosis.

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 antigenic relationship between Leptospira interrogans, equine cornea and lens was previously noted in our studies. Serum antibodies from horses inoculated with serovars wolffi, pomona, icterohaemorrhagiae, and tarassovi, were able to bind to five antigenic fractions from both cornea and lens, as demonstrated by immunoblotting. These antigens seem to be made up of protein and carbohydrates. After treatment with periodate for cleavage of glycoside ring structures, those fractions kept their condition of target for anti-Leptospira antibodies. Nevertheless, all fractions lost that condition after being subjected to peptide hydrolysis.

Equine recurrent uveitis (ERU) is the most frequently encountered cause of eye problems and blindness in horses. Classic treatment of ERU includes mydriatics, corticosteroids and nonsteroidal anti-inflammatory drugs. Despite vigorous topical and systemic treatment, however, in many cases, the prognosis for preserving vision remains poor. Experiences with surgical treatment of chronic endogenous uveitis in human patients have shown that vision-impairing axial opacities in the vitreous body can be removed by pars plana vitrectomy, and that a considerable decrease in the frequency and severity of uveitic relapses results. So far, 11 eyes of 10 horses were subjected to vitrectomy. All horses had suffered from 3 or more uveitic attacks and had a hazy vitreous. In all cases, at discharge from the clinic, the vitreous chamber was less hazy compared to preoperative findings. At follow-up examinations, 8 eyes (8/10) had normal i.o. pressure, and 2 (2/10) had subnormal i.o. pressure and the vitreous chambers were clear or contained only small floaters. Uveitic attacks had not been observed in the operated eyes. Postoperative complications included fibrinous, or fibrinous-haemorrhagic exudate in the anterior chamber of all eyes, and in one eye, a minor haemorrhage in the vitreous chamber. Our preliminary results indicate that pars plana vitrectomy assuring proper case selection and accurate surgical technique, may contribute to improvement of vision and may delay the progression of uveitic complications in horses.

In this paper ophthalmological and clinical results as well as the literature on lens-induced uveitis (LIU), a relatively unknown pathological syndrome in domestic animals, are presented. Out of all ocular material sent to the Institute of Pathology, GSF, from 1970 until 1990 (n = 864), 40 individual cases of LIU (14 cases in dogs, 13 in cats, 10 in rabbits, 1 in a horse and 2 in birds) were diagnosed. The histology of the eyes of the cases is characterized by a lesion of the lens capsule and a consequent reactive phacogenic inflammation of the anterior segment of the eye in the region of the anterior uvea. A comparison of the history and ophthalmological diagnosis indicates that 36 lens-induced uveitis cases occurred following a (spontaneous) traumatic injury to the eye, whereby the anterior lens capsule was perforated with the result of the lens material being exuded into the anterior uvea (iris-ciliary body region). The strongly vascularized anterior uvea is used as a carrier and a connecting link to the immune system. None of the histologically examined cases of LIU were diagnosed as such clinically. This can be explained by the fact that the uveitis is difficult to recognize on account of overlying secondary alterations in the eye. Nevertheless the morphological substrate of LIU is considered to be pathognomonic. The inflammatory and cellular reactions leading to a release of the lens material observed in domestic and laboratory animals exhibit only slight parallels to those observed in man. The case history of animals usually reveals a traumatic injury and an endophthalmitis (with or without secondary glaucoma) which cannot be controlled therapeutically. The therapy for promptly diagnosed cases should be a lens extraction to save the affected eye and its sight. In advanced cases the enucleation of the bulbus is the therapy of choice.

Although experimental models of autoimmune uveitis predict pinealitis coincident with uveitis, there is no direct evidence of pineal pathology accompanying a human uveitis. Horses with naturally occurring uveitis are a potential source of eye and pineal tissues that are not available from human patients with active uveitis. We have observed pinealitis in a mare with equine recurrent uveitis. By immunohistochemistry we demonstrated immunoglobulin and MHC Class II antigen on infiltrating and resident cells of eye and pineal gland. These results support the relevance of the animal models and suggest that pinealitis may be coincident with some human uveitides.

In the paper presented, the histological findings in four cats with glaucoma are reported by means of HE-stained paraffin embedded sections. To each case a clinical anamnesis is given. The authors describe primary glaucomas as well as secondary glaucomas of different aetiology. A dysplastic pectinate ligament can be identified for the first time in a cat. Clinical and histological findings are discussed and compared to the findings in dogs.

Dogs were treated with flunixin meglumine, a cyclooxygenase inhibitor; L-651,896, a 5-lipoxygenase inhibitor; and matrine, a herbal anti-inflammatory drug. Acute inflammation was induced in the eyes by disruption of the anterior lens capsule, using a neodymium:yttrium aluminum garnet laser. Intraocular pressure, pupil diameter, and eicosanoid production in the aqueous humor were measured. Statistically significant effects were seen in the eyes of flunixin meglumine-treated dogs where mydriasis was maintained and aqueous prostaglandin E2 concentration was reduced.

The medical records of 12 horses that had cataracts removed by use of phacofragmentation were reviewed. Cataracts were removed from 16 eyes in horses ranging in age from 2 months to 15 years. Complications after surgery included corneal ulcers in 13 eyes, diffuse corneal edema in 5 eyes, and uncontrollable uveitis in 3 eyes. Follow-up information was obtained in all horses from 1 month to 3.5 years after surgery. Visual results were judged good by owners or veterinarians in 10 of the horses.

Histopathologic findings in 158 globes obtained from 139 cats by enucleation or at necropsy, with histopathologic diagnosis of uveitis, were compared, and morphology was correlated with clinical and/or histopathologic diagnosis. The most common morphologic feature was a lymphocytic-plasmacytic anterior uveal infiltrate that was either diffuse or nodular; specific cause could not be associated with this nongranulomatous anterior uveitis. In decreasing order of frequency, other common causes of uveitis in cats included feline infectious peritonitis; FeLV-associated lymphosarcoma; trauma; and lens-induced uveitis.

Five horses with severe nonulcerative keratouveitis had corneal lesions characterized by a pink stromal infiltrate that initially appeared in the stroma near the limbus. Unremitting iridocyclitis also was evident. In 3 horses, microscopic lesions consisted of marked corneal stromal fibrosis, with mild to severe inflammatory cellular infiltration. Corticosteroids and mydriatic/cycloplegics applied topically and corticosteroids and nonsteroidal anti-inflammatory medications administered parenterally were used with varying degrees of success to control pain and retain vision.

Uveitis, inflammation of the vascular middle coat of the eye, may be a common manifestation of several diseases. Clinical signs of uveitis include ocular discharge, redness, and pain. Uveitis should be differentiated from other conditions causing similar clinical signs. Once uveitis is recognized, attempts to identify a specific cause should be undertaken. In some cases, an underlying cause is not identified, and treatment is aimed at preventing additional ocular damage.

Four cyclocryosurgical procedures were compared for effects on normal canine eyes. All procedures produced a significant (P less than 0.05) decrease in intraocular pressure, a marked uveitis, ciliary epithelial cell loss, edema and engorgement of the ciliary processes, iris necrosis, protein effusion, chemosis, and mild discomfort, as indicated by mild blepharospasm and slight epiphora. The histopathologic changes were evaluated at 5 minutes, 1 week, 1 month, and 6 months after surgery. The ciliary epithelium was normal in appearance and intraocular pressure had returned to the normal range at 6 months after surgery. The adverse reactions to the cyclocryosurgical procedures included retinal detachments, chemosis, conjunctivitis, transient increased intraocular pressure, uveitis, iris depigmentation, and corneal granulation tissue.

Infection with Borrelia burgdorferi caused panuveitis and arthritis in a pony. Spirochetes were detected by direct immunofluorescence in the anterior chamber of the eye. The carpal joints had severe degenerative joint disease, with synovial proliferation. The synovium and serum had B burgdorferi antibody titers of 1:1024. The pony lived in an area of Wisconsin where infection with B burgdorferi is endemic in human beings. Previously, serum antibodies to B burgdorferi had been found in horses, but disease had not been reported.

Three cryosurgical units were compared on the basis of the ability of each unit to freeze the ciliary body of enucleated normal canine eyes. The coldest average temperatures reached were -13.4 C, -4.3 C, and -17.6 C. One of the units was then used to freeze the ciliary body in the left eye of 25 dogs for 5 minutes. Ciliary body temperatures were monitored every 15 s during cyclocryosurgery. In 18 eyes in situ, the coldest average temperature reached was -13.4 C. In 7 proptosed globes, the coldest average temperature reached was -13.8 C. The results were not significantly different (P less than 0.05). The effects of the cryosurgery and centesis procedure were monitored daily by direct observation and Schiotz's tonometry. Histologic changes from the procedure were evaluated at 5 minutes, 1 week, 1 month, and 6 months after surgery. Intraocular pressure returned to the normal range within 1 to 2 weeks, the anterior uveitis subsided in 7 to 10 days, and ciliary body epithelium was histologically normal within 6 months after surgery.

In the studies attempts were to demonstrate the occurrence of immunological reactivity against antigens of the lens and tunica vascularis of the eye in periodical inflammation of eyes in horses. For this purpose antigens from the lens and tunica vascularis of the eye, prepared in our laboratory, were used in the experiments. The reactivity of horses with monthly symptoms of blindness against the above antigens was determined in vivo (skin tests and PCA) and in vitro (ID reaction). The results obtained mainly in skin tests account for its occurrence in some percentage of diseased animals, because in 24 horses examined in this direction six instant reactions and seven semi-retarded reactions against the lens antigens were obtained. Positive reactions against antigens of tunica vascularis were observed in nine and eight cases, respectively. No positive reactions were observed in PCA, whereas in ID reaction specific antibodies against lens antigens were found only in two cases.

Pleural effusion disease (PED) is a generalized infection of laboratory rabbits caused by a virus-like agent. The disease was first described in the late sixties as a mortality problem among rabbits used for the propagation of Nichols' pathogenic Treponema pallidum in Scandinavian laboratories using the T. pallidum immobilization (TPI) test for the serological diagnosis of syphilis. The iridocyclitis, described as a manifestation of PED, has been studied in detail in rabbits experimentally infected with the PED agent. All rabbits surviving the acute phase of infection developed a non-pyogenic, non-granulomatous anterior uveitis during the "viraemic" stage of infection. The ocular signs of disease culminated between days 3 and 6 and disappeared within 2 to 3 weeks. No recurrence of uveitis was observed during a 6-months observation period, nor by subsequent subcutaneous re-inoculation of the PED agent. Histologically, the uveal reaction was mild and regressed almost completely within 4 weeks. Discrete choroidal inflammatory foci occurred in some of the re-inoculated rabbits, but without changes in the anterior eye segment. The uveitis of pleural effusion disease in rabbits seems to be caused directly by the virus-like agent. It might possibly serve as a simple and reproducible model in further uveitis research.