Evisceration with implantation of an intrascleral silicone prosthesis in dogs: A retrospective study of 107 cases (2010-2019).

OBJECTIVE: To retrospectively analyze the preoperative clinical characteristics and surgical outcomes of evisceration with implantation of an intrascleral silicone prosthesis (EIISP) procedures in dogs and evaluate whether brachycephalic dogs are more prone than non-brachycephalic dogs to develop postoperative complications after EIISP. ANIMAL STUDIED: Ninety-One dogs (19 of which were brachycephalic) were included. PROCEDURES: Medical records from 2010 to 2019 were reviewed. Signalment, reason for EIISP, postoperative complications, follow-up time, and postoperative eye appearance were analyzed. RESULTS: The most frequently represented breeds were French Bulldog [11/91 (12%) dogs], Jack Russell Terrier [6/91 (7%)], and Shih Tzu [6/91 (7%)]. Brachycephalic dogs were statistically younger than non-brachycephalic dogs at the time of EIISP (p = 1.61 × 10-5 ). Uncontrolled glaucoma was the most common reason for EIISP in both groups. Short-term complications (from D0 to D15) seen in 7/91 (8%) dogs included epithelial corneal ulcers (n = 3), keratoconjunctivitis sicca (KCS) (n = 2), and prosthesis extrusion (n = 2). Long-term complications seen in 26/91 (29%) dogs included KCS (n = 11), epithelial corneal ulcers (n = 7), stromal ulcers (n = 3), entropion (n = 4), and prosthesis extrusion (n = 1). Extrusion of the prosthesis occurred twice in eyes that had undergone diode laser transscleral cyclophotocoagulation. The risk of postoperative complications was not significantly different between brachycephalic and non-brachycephalic dogs (p = .3). CONCLUSIONS: Brachycephalic status in dogs does not appear to influence the risk of complications from EIISP. Nevertheless, the present study is a reminder that EIISP focuses on esthetics, and considering the possible complications associated with it, it does not provide a benefit to the patient compared to enucleation.

A review of diagnostic tests for qualitative and quantitative tear film deficiency in dogs.

Dry eye disease (DED) is a complex multifactorial condition caused by loss of ocular surface homeostasis from quantitative and/or qualitative tear film deficiency. Schirmer tear test (STT) is often the only diagnostic test used to assess for DED in veterinary practice. STT is invaluable in the diagnosis and monitoring of quantitative tear film deficiency (i.e., keratoconjunctivitis sicca); however, it is not sufficient to optimize therapy and fully recognize other contributing factors for the disturbance in ocular surface homeostasis. The present work reviews diagnostic tests for assessing aqueous tear production in veterinary medicine, as well as the quality of tears, corneal epithelial barrier integrity, and the lacrimal functional unit.

Topical applications of allogeneic adipose-derived mesenchymal stem cells ameliorate the canine keratoconjunctivitis sicca.

BACKGROUND: Canine keratoconjunctivitis sicca (KCS) is predominantly an immune-mediated disease. Current therapy of canine KCS is mainly by immunosuppressant, but the effectiveness was limited in some patients. In the past few years, some studies showed the results of the use of mesenchymal stem cells in treating canine KCS via periocular injections. However, the periocular injection procedure requires sedation or general anesthesia, and may lead to iatrogenic or incidental injury during the injection process. The aim of this study was to investigate the efficacy of topical allogenic canine adipose-derived mesenchymal stem cells (cAD-MSCs) in clinical patients of canine KCS. RESULTS: The cAD-MSCs used in this study were characterized for their capability of tri-lineage differentiation and immunomodulatory properties. In addition, preparation methods for eye drops of cAD-MSCs was developed and its optimal preservation was tested. The canine KCS patients were recruited for clinical trial and divided into two groups based on their history of previous treatment. All patients received topical cAD-MSCs treatment once per week for 6 consecutive weeks and complete ophthalmic examinations were performed 1 week before treatment (week 0) and at 3rd, 6th, 9th weeks, respectively. The results showed that the quantity and quality of tears have improved significantly following topical cAD-MSCs treatment based on Schirmers tear test-1 and tear break-up time. More than half of all patients were found improved in the tear quantity. In particular, 56.5% of the patients that were unresponsive to prior immunosuppressant therapy had an effective increase in tear volume. The severity of clinical signs was also ameliorated according to the numeric rating scale score from both patient owners and the clinician. CONCLUSION: To sum up, topical cAD-MSCs may be beneficial especially in KCS patients with poor owner compliance for frequent daily use of eye drops or those who are unresponsive to immunosuppressant therapy.

Assessment of tear film osmolarity using the IPen® Vet osmometer in Pug and Shih-Tzu dogs with and without keratoconjunctivitis sicca.

OBJECTIVE: To establish tear film osmolarity (TFO) values in Pugs and Shih-Tzus, with and without keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: A total of 82 adult dogs were evaluated. PROCEDURE: The inclusion criteria for the healthy group was a Schirmer tear test (STT-1) ≥15 mm/min with no clinical signs of KCS, whereas those with KCS had clinical signs and a STT-1 ≤10 mm/min. All animals underwent complete ophthalmological evaluation prior to STT-1 and TFO. Student's t tests were used to compare STT-1 and TFO in KCS and healthy eyes as well as possible differences in TFO between breeds. In addition, a linear regression to model the relationship between the two variables (STT-1 and TFO) was performed. A P-value ≤ 0.05 was considered statistically significant. RESULTS: STT-1 results were significantly lower (p = 0.0001) in the KCS group (4.46 ± 1.74) compared with the control group (18.80 ± 2.02). Mean TFO results were significantly higher in the KCS group (353.02 ± 16.58 mOsm/L) (p < 0.0001) compared with the control group (315.27 ± 6.15 mOsm/L). The formula Y = 365.059-2.625 * X significantly predicts (p < 0.001) the value of the variable Y (TFO mOsm/L) as a function of the variable X (STT-1 mm/min), with a coefficient of determination of 0.71. CONCLUSIONS: The results revealed differences in TFO and STT-1 between KCS and healthy dogs. Additionally, STT-1 and TFO values were correlated with the aim to use STT-1 values to predict TFO values in brachycephalic breeds.

Neurogenic keratoconjunctivitis sicca in 34 dogs: A case series.

OBJECTIVE: To describe the clinical findings, imaging features, underlying conditions, treatment, and progression of dogs presented between 2010 and 2019 with neurogenic keratoconjunctivitis sicca (NKCS). METHODS: Dogs diagnosed with NKCS were searched in the clinical database. Inclusion criteria were STT-1 readings <15 mm/min, clinical signs of KCS with concurrent ipsilateral xeromycteria. RESULTS: Thirty-four cases were identified. Mean age at presentation was 8.2 years, median 8.9 years (0.3-14.7). Twenty dogs were male, and 14 dogs were female. Concurrent neurological deficits included facial neuropathy (n = 13, 38%), peripheral vestibular syndrome (n = 10, 29%), and Horner's syndrome (n = 5, 15%). Advanced imaging was acquired in 53% of cases (n = 18). Etiologies included idiopathic (n = 18, 53%), endocrinopathy (n = 6, 18%), otitis interna (n = 4, 12%), head trauma (n = 3, 9%), iatrogenic (post-TECA-LBO, n = 1, 3%), brainstem mass (n = 1, 3%), and an area of inflammation in the pterygopalatine fossa (n = 1, 3%). Treatment for NKCS was initiated in most cases (n = 30, 88%) including: oral pilocarpine 2% and lacrimostimulant (n = 19), oral pilocarpine 2% only (n = 3), or lacrimostimulant only (n = 8). A mean time follow-up of 3.7 months, median 3 months (1-14) was available in 23 cases (68%). Eleven cases with follow-up were responsive (48%) with resolution of the clinical signs in a median time 4 months (1-10), and all of them were treated with oral pilocarpine (±lacrimostimulant). CONCLUSIONS: Most cases presented as idiopathic NKCS; in others, an underlying cause of facial neuropathy was identified. All responsive cases were treated with oral pilocarpine 2%.

Efficacy of adjunctive therapy using Vizoovet in improving clinical signs of keratoconjunctivitis sicca in dogs: A pilot study.

OBJECTIVE: To assess the clinical safety and efficacy of adjunctive therapy using Vizoovet to ameliorate clinical signs of keratoconjunctivitis sicca (KCS) in dogs. ANIMALS STUDIED: Twenty client-owned dogs. PROCEDURES: Canine patients diagnosed with KCS were enrolled in this prospective study. Patients were randomly selected to receive either Vizoovet or GenTeal drops twice daily in addition to twice daily tacrolimus 0.03% solution. Data were collected from only one eye of each patient and included STT-1, IOP, TFBUT, and results of objective clinical scoring performed by pet owners. Statistical significance was set at P ≤ .05. RESULTS: In all, 20 dogs (20 eyes) were enrolled in this prospective randomized study. Females (n = 12; 60%) outnumbered males (n = 8; 40%) and all dogs were spayed/neutered. Mean age of all dogs was 10.6 ± 3.79 years. In both treatment groups, the improvement in STT-1 values over the course of the study was significant (P = .002). When comparing the STT-1 improvements between groups, no significance was found (P = .78). In both groups, the improvement in TFBUT was significant (P = .0018). When comparing the TFBUT improvements between groups, no significance was found (P = .14). Squinting, rubbing, ocular discharge, and medication administration scores all significantly improved throughout the course of the study; however, they did not differ significantly between groups. Throughout the study, no adverse side effects were noted clinically or by the pet owner in either group. CONCLUSIONS AND CLINICAL RELEVANCE: Adjunctive treatment with Vizoovet was as safe and effective as GenTeal drops at improving clinical signs of dry eye in dogs.

Assessment of meibomian gland morphology by noncontact infrared meibography in Shih Tzu dogs with or without keratoconjunctivitis sicca.

OBJECTIVE: To investigate meibomian gland (MG) morphology by noncontact infrared meibography in Shih Tzu dogs with or without keratoconjunctivitis sicca (KCS). PROCEDURES: Fourteen eyes of 12 Shih Tzu dogs (mean age of 10.7 years, range of 7-13 years) presented to Yakumo Animal Hospital or Triangle Animal Eye Clinic from 2011 to 2017 with clinical signs and a Schirmer tear test (STT) result consistent with KCS (<10 mm/min) were examined. Twenty-eight eyes of 16 Shih Tzu dogs (mean age of 12.4 years, range of 8 to 15 years) with a STT > 15 mm/min served as healthy controls. Both groups of dogs underwent routine slitlamp biomicroscopy followed by noncontact infrared meibography of the upper eyelid with both desktop-type and mobile-type systems. Results Meibography revealed morphological abnormalities of MGs in 13 eyes of 11 dogs with KCS. The abnormalities included gland shortening in 64% and gland dropout in 64% of the 14 eyes in the KCS group. Morphological changes were also observed in MGs of 16 eyes of 10 dogs in the control group. These changes included shortening in 46% and dropout in 17.8% of the 28 eyes in the control group. Dropout was significantly more common in eyes with KCS than in control eyes (P < 0.01). Conclusions The frequency of MG abnormalities is increased in Shih Tzus with KCS compared with control animals. A reduced quality of the tear film associated with increased evaporation and reduced retention of tear fluid likely exacerbates the effects of a reduced tear volume in animals with aqueous deficiency.

Nuclear parameters and chromatin remodeling in epithelial cells and lymphocytes from the palpebral conjunctiva of dogs with keratoconjunctivitis sicca.

OBJECTIVE: To study parameters related to nuclear morphology and chromatin remodeling in epithelial cells and lymphocytes from the inferior palpebral conjunctiva of dogs with and without keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: Thirty-two dogs (64 eyes) were included in the study. Based on the tear production measured by Schirmer tear test 1, the dogs were distributed into control and KCS groups. PROCEDURES: Epithelial cells and lymphocytes were collected by conjunctival brush cytology, fixed on glass slides, and subjected to the Feulgen reaction, a topochemical method specific for DNA/chromatin. Feulgen-stained cells were studied by microscopy and video image analysis to establish nuclear size (area and perimeter) and shape (relative nuclear roundness factor = RNRF), DNA content (ploidy), and compaction and texture of chromatin. RESULTS: Conjunctival samples in the KCS group showed infiltration of inflammatory and immune cells. Micronuclei, snake-like chromatin, aberrant chromosomes, and goblet cells were not detected. Compared with the controls, cells on the conjunctival surface of dogs with KCS showed altered nuclei. Conjunctival epithelial cells were more affected by KCS (changes in nuclear size, shape, DNA content, and chromatin compaction) than lymphocytes (changes in chromatin compaction, only). Significant chromatin decompaction was observed in both conjunctival epithelial cells and lymphocytes. CONCLUSIONS: Our results show that KCS promotes chromatin remodeling in epithelial cells and lymphocytes on the conjunctival surface of dogs. The changes described in this study are different from those reported for conjunctival cell nuclei of human KCS patients.

Comparative efficacy of topical oclacitinib 0.1% and tacrolimus 0.01% in canine keratoconjunctivitis sicca.

OBJECTIVE: To assess the efficacy of 0.1% oclacitinib as a single agent, and in combination with tacrolimus 0.01%, for the control of ophthalmic signs of keratoconjunctivitis sicca (KCS) in dogs. ANIMALS STUDIED: Thirty-two dogs (57 eyes) diagnosed with idiopathic KCS were included. Inclusion criteria were Schirmer Tear Test 1 (STT-1) values <15 mm/min and concurrent clinical signs such as ocular hyperemia and discharge. PROCEDURES: The animals were submitted to a randomized, open-label, 5-week study and divided into 3 treatment groups treated with the following ophthalmic solutions: (a) 0.1% oclacitinib, (b) 0.1% oclacitinib +0.01% tacrolimus, and (c) 0.01% tacrolimus. Eye drops were instilled twice daily (12-hour intervals). At each follow-up examination, STT-1, clinical signs, and potential drug side effects were assessed. RESULTS: Oclacitinib did not significantly improve STT-1 values or clinical scores. Tacrolimus alone and in combination with oclacitinib increased mean STT-1 values by 11.84 ± 5.2 and 12.46 ± 5.3 mm/min, respectively (P = 0.0001). Clinical scores of ocular discharge and hyperemia also improved significantly in both groups receiving treatment with tacrolimus (P < 0.05). However, addition of oclacitinib to tacrolimus provided no additional improvement over tacrolimus alone. CONCLUSIONS: Topical 0.1% oclacitinib twice daily is not effective in controlling the ocular signs of KCS in dogs. 0.01% tacrolimus increased STT-1 values significantly and could potentially be used as a treatment for mild-to-moderate cases of KCS. Synergism between drugs did not occur, and therefore the use of oclacitinib is not justified in cases of canine KCS.

Canine oral mucosa evaluation as a potential autograft tissue for the treatment of unresponsive keratoconjunctivitis sicca.

PURPOSE: Labial mucosa transplantation for the treatment of canine keratoconjunctivitis sicca (KCS) has been reported recently. Postoperative alleviation of clinical signs was noted and assumed to be the result of labial salivary glands providing lubrication to the ocular tissue. The aim of this study was to evaluate the presence of minor salivary glands (MSG) in the canine oral mucosa. METHODS: Oral mucosal biopsies were collected from six dogs that died (n = 1) or were euthanized (n = 5) for reasons unrelated to this study. The breeds included were two Doberman Pinschers, one Labrador Retriever, one Portuguese Water Dog, one German Shepherd Dog, and one mixed canine. Three were spayed females, and three were castrated males with the median age of 9 years (range, 6-13 years). Samples were obtained by an 8-mm punch biopsy at the following locations of the canine oral cavity: upper rostral labial mucosa at midline, lower rostral labial mucosa at midline, upper labial mucosa near the commissure, lower labial mucosa near the commissure, and buccal mucosa approximately 1 cm caudal to the commissure. Samples were routinely processed with hematoxylin and eosin, and periodic acid-Schiff stains. Samples were evaluated by light microscopy. RESULTS: At the selected locations, no MSG or other secreting cells were detected. CONCLUSIONS: Minor salivary glands are not associated with alleviation of canine KCS symptoms following labial mucosa transplantation. Further studies are needed to determine the mechanism leading to the transient improvement of KCS symptoms in canine patients following labial mucosa transplantation.

The effects of topical aqueous sirolimus on tear production in normal dogs and dogs with refractory dry eye.

PURPOSE: To evaluate the effect of twice daily aqueous 0.02% sirolimus drops on tear production in normal dogs and dogs with refractory keratoconjunctivitis sicca (KCS). METHODS: Two groups of dogs were studied. Ten normal dogs with no signs of ocular disease were administered topical 0.02% sirolimus ophthalmic solution in right eye, and a vehicle control in the left eye twice daily for 4 weeks. Complete ophthalmic examinations, including Schirmer tear test were performed weekly. Eighteen dogs with refractory KCS were randomly assigned to receive 0.02% sirolumus ophthalmic solution or 0.02% tacrolimus ophthalmic solution twice daily. Complete ophthalmic examinations were was performed at 2 and 6 weeks following treatment. RESULTS: Tear production in the sirolimus-treated eyes of normal dogs was greater when compared to vehicle controls with a mean difference over all time points of 3.46 mm (95% CI 1.17, 5.75; P = 0.006). After 4 weeks of treatment, the mean difference was 5 mm (95% CI 1.95, 8.05; P = 0.002). In dogs with refractory dry eye, 37.5% of eyes treated with sirolimus exhibited increased tear production >4 mm/min after 6 weeks of treatment, compared to 20% of eyes receiving tacrolimus (P = 0.433). One normal dog experienced topical irritation to both sirolimus and vehicle-treatment. Side effects were not reported in any treated eyes with chronic KCS. CONCLUSION: Topical 0.02% sirolimus might be an alternative treatment for canine patients with keratoconjunctivits sicca. The drug appears safe when applied topically in an aqueous suspension for up to 6 weeks. While initial results are promising, further studies are warranted.

Assessment of corneal and conjunctival metaplasia by impression cytology during the treatment of canine keratoconjunctivitis sicca.

The purpose of this study was to assess the condition of cells in the conjunctiva and corneal epithelium prior to and during cyclosporine- or tacrolimusbased treatment of keratoconjunctivitis sicca (KCS). The study was performed on 40 dogs with KCS. The dogs were divided into two groups of 20 animals each. In Group I, 0.75% cyclosporine eye drops were administered three times a day, while in Group II 0.02% tacrolimus eye drops were administered twice daily. Additionally, each group was subdivided into three subgroups based on the results of the Schirmer I tear test (STT I). Evaluation of cellular metaplasia in the cornea and the palpebral and bulbar conjunctiva based on the Nelson-Adams scale was performed by impression cytology using Millipore round filters (Millipore VSWP 01300 DA) of 25 µm pore diameter applied to the studied area. Ophthalmological and cytological examinations were performed prior to the treatment as well as after one and two months of therapy. In both groups, a decrease in Nelson-Adams values was observed, corresponding to the increasing STT values [Rxy Spearman statistically significant correlation coefficient values between -0.75 (P < 0.001) and -0.45 (P < 0.01)]. The absence of goblet cells was observed in all dogs, regardless of the KCS stage. Goblet cells reappeared following both tacrolimus- and cyclosporine-based treatment in impression cytology specimens classified as 0 in the Nelson-Adams scale. The extent of corneal and conjunctival metaplasia in the course of tacrolimus- and cyclosporine-based treatment of KCS decreases with increasing STT values.

Assessment of tear film osmolarity using the TearLab™ osmometer in normal dogs and dogs with keratoconjunctivitis sicca.

OBJECTIVE: To evaluate repeatability and reproducibility of tear osmolarity measured using the TearLab™ osmometer in normal dogs and to assess its diagnostic potential in dogs with keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: Beagle dogs; six normal and five with KCS. PROCEDURES: Tear osmolarity and Schirmer tear test-1 (STT-1) values were obtained at various times. Normal dogs were assessed for diurnal variation and repeatability and reproducibility of measurements. Dogs with KCS were evaluated before and after 5 months' topical twice-daily therapy with 2% cyclosporine. RESULTS: Mean ± SD tear osmolarity (mOsm/L) was significantly higher in normal dogs (337.4 ± 16.2) than in dogs with KCS before therapy (306.2 ± 18.0; P < 0.0001), but not following therapy with 2% cyclosporine (330.5 ± 13.7; P = 1.00). Osmolarity readings lower than 325.5 mOsm/L were suggestive of KCS (84.8% sensitivity and 87.1% specificity). In normal dogs, tear osmolarity readings were stable during the daytime (P = 0.99). Repeated measurements revealed high variability and typically poor-to-moderate repeatability and reproducibility, although this was improved by taking three successive measurements at each session. Considering combined data from all dogs, a positive correlation existed between STT-1 and tear osmolarity measurements (Pearson's correlation test, P = 0.04, r = 0.62). CONCLUSIONS: Canine tear osmolarity as determined by TearLab™ osmometer was variable, required multiple readings to be informative, and differed from values reported for humans. Dogs with KCS had a lower tear osmolarity than did normal dogs, and this increased following cyclosporine therapy.

Episcleral cyclosporine A implants for the management of unilateral keratoconjunctivitis sicca in an 8-year-old mare.

An 8-year-old mare was presented for investigation of a 1-month history of blepharospasm, eyelid swelling, corneal edema, and ocular discharge of the right eye (OD). Ophthalmic examination confirmed mucopurulent ocular discharge, conjunctival hyperemia, and a dry, dull appearance to the cornea OD. Schirmer tear test results confirmed an absence of tear production OD (0 mm/min) consistent with keratoconjunctivitis sicca. Treatment with topical 0.2% cyclosporine A resulted in an improvement in clinical signs. An episcleral cyclosporine A implant was placed under standing sedation 5 days after initial presentation. Re-examination 9 days post-operatively confirmed that the mare's tear production in the right eye had improved and no further clinical signs had been observed. Topical medications were gradually discontinued. Re-examinations performed up to 12 months postsurgery showed no recurrence of clinical signs and no adverse effects of the implant. To our knowledge, this is the first report of the use of a cyclosporine A implant in the management of KCS in a horse and highlights its potential as an effective, alternative therapy in the management of KCS in horses.

Clinical evaluation of a nutraceutical diet as an adjuvant to pharmacological treatment in dogs affected by Keratoconjunctivitis sicca.

BACKGROUND: Canine keratoconjunctivitis sicca (cKCS) is an inflammatory eye condition related to a deficiency in the tear aqueous fraction. Etiopathogenesis of such disease is substantially multifactorial, combining the individual genetic background with environmental factors that contribute to the process of immunological tolerance disruption and, as a consequence, to the emergence of autoimmunity disease. In this occurrence, it is of relevance the role of the physiological immune-dysregulation that results in immune-mediated processes at the basis of cKCS. Current therapies for this ocular disease rely on immunosuppressive treatments. Clinical response to treatment frequently varies from poor to good, depending on the clinical-pathological status of eyes at diagnosis and on individual response to therapy. In the light of the variability of clinical response to therapies, we evaluated the use of an anti-inflammatory/antioxidant nutraceutical diet with potential immune-modulating activity as a therapeutical adjuvant in cKCS pharmacological treatment. Such combination was administered to a cohort of dogs affected by cKCS in which the only immunosuppressive treatment resulted poorly responsive or ineffective in controlling the ocular symptoms. RESULTS: Fifty dogs of different breeds affected by immune-mediated cKCS were equally distributed and randomly assigned to receive either a standard diet (control, n = 25) or the nutraceutical diet (treatment group, n = 25) both combined with standard immunosuppressive therapy over a 60 days period. An overall significant improvement of all clinical parameters (tear production, conjunctival inflammation, corneal keratinization, corneal pigment density and mucus discharge) and the lack of food-related adverse reactions were observed in the treatment group (p < 0.0001). CONCLUSIONS: Our results showed that the association of traditional immune-suppressive therapy with the antioxidant/anti-inflammatory properties of the nutraceutical diet resulted in a significant amelioration of clinical signs and symptoms in cKCS. The beneficial effects, likely due to the presence of supplemented nutraceuticals in the diet, appeared to specifically reduce the immune-mediated ocular symptoms in those cKCS-affected dogs that were poorly responsive or unresponsive to classical immunosuppressive drugs. These data suggest that metabolic changes could affect the immune response orchestration in a model of immune-mediated ocular disease, as represented by cKCS.

Comparative clinical evaluation of tacrolimus and cyclosporine eye drops for the treatment of canine keratoconjunctivitis sicca.

The aim of this study was to evaluate the efficacy of tacrolimus eye drops in alleviating the clinical symptoms of canine keratoconjunctivitis sicca (KCS) and to compare this efficacy with that of cyclosporine. The clinical study was conducted on 40 dogs diagnosed with idiopathic KCS. The dogs were divided into two groups of 20 animals each. In Group I, 0.75% cyclosporine eye drops were administered three times a day, while in Group II 0.02% tacrolimus eye drops were given twice daily. In addition, each group was subdivided into three subgroups based on the results of Schirmer tear test I (STT I). Clinical and ophthalmologic examinations were performed prior to the treatment as well as after one and two months of therapy. The application of both tacrolimus and cyclosporine resulted in a significant reduction of neovascularisation after the first and second month of treatment (P < 0.05, P < 0.001); however, in moderate and advanced stages, the observed efficacy of tacrolimus was higher. Across all patients, a significant increase in STT I values was observed after both the first and second month of treatment with tacrolimus (P < 0.01), as well as after two months of treatment with cyclosporine (P < 0.05). In both groups, some patients were observed to exhibit inhibited development of pigmentation, but an analysis of particular clinical cases and statistical data revealed no statistically significant discrepancies in the course of the study. In cases of advanced canine KCS, the efficacy of tacrolimus may be higher than that of cyclosporine.

Infrared ocular thermography in dogs with and without keratoconjunctivitis sicca.

Infrared thermography was used to measure temperature differences of the corneal surface between nasal and temporal limbus regions and central cornea of normal dogs and dogs with keratoconjunctivitis sicca (KCS), in order to establish temperature values in normal canine eyes and in patients with decreased Schirmer tear tests (STT) values. Dogs investigated were all either patients seen at the Veterinary Teaching Hospital of Federal University of Paraná or normal dogs that belonged to the same institution. STT were performed in all eyes. A total of 40 control eyes (STT ≥15 mm/min) and 20 eyes with low STT values (STT ≤14 mm/min) were examined. The mean STT value for eyes with normal STT values was 22.9 ± 3.9 mm/min (mean ± standard deviation), and the mean STT value for eyes with low STT value was 7.2 ± 4.8 mm/min. The mean corneal temperature was significantly lower in eyes with low STT values than in control eyes (P < 0.0001). The following significant correlations were found: (i) Schirmer and breakup time (BUT) (P = 0.0001, r = 0.5); (ii) STT values and corneal surface temperature (P = 0.001, r = 0.256); (iii) STT values and age (P = 0.0001, r = -0.448); (iv) age and corneal surface temperature (P = 0.0001, r = -0.281); and (v) BUT and corneal surface temperature (P = 0.0001, r = 0.36). Thermography is a method that can differentiate between eyes with normal and abnormal STT values. In the future, thermography might be incorporated as part of the ophthalmic examination and perhaps become a popular ancillary test for the diagnoses of ocular surface disorders.

Retrospective study of the prevalence of keratoconjunctivitis sicca in diabetic and nondiabetic dogs after phacoemulsification.

OBJECTIVE: To evaluate the prevalence of keratoconjunctivitis sicca (KCS) in diabetic and nondiabetic dogs following phacoemulsification. PROCEDURES: Medical records were reviewed for signalment, body weight, diabetes status, and STT at the preoperative and all postoperative examinations. A clinical diagnosis of KCS was defined as a STT <15 mm/min with compatible clinical signs. Schirmer tear test values and the prevalence of KCS based on STT <15 mm/min were evaluated at 2-4, 5-8, 9-14, 15-20, and 41-52 weeks postoperatively. Size of dog (large, >10 kg; small, ≤10 kg) and STT ranges (<15 mm/min, 15-22 mm/min and >22 mm/min) were categorized for analysis of effect of body weight and STT on prevalence of KCS. RESULTS: One hundred and seventeen nondiabetic (198 eyes) and 118 diabetic dogs (228 eyes) were evaluated. KCS was diagnosed in nearly twice as many diabetics as nondiabetics (27.4% vs. 15.4%) within 2 weeks postoperatively (P = 0.0088). Percentage of eyes with KCS among all dogs decreased over time and did not differ significantly after the first postoperative visit. Diabetic small dogs were 1.7 times more likely to have KCS than nondiabetic small dogs (P = 0.0052). Preoperative STT was significantly associated with likelihood of postoperative KCS among large (P < 0.0001), but not small dogs (P = 0.0781). Among large dogs, eyes with STTs between 15 and 22 mm/min were approximately 3 times more likely to be diagnosed with KCS after surgery than those with STT >22 mm/min. CONCLUSION: The greatest risk for KCS for all dogs is during the first 2 weeks postoperatively. Populations at greatest risk for postoperative KCS are small dogs, small diabetic dogs, and large dogs with preoperative STT ≤22.

Use of episcleral cyclosporine implants in dogs with keratoconjunctivitis sicca: pilot study.

PURPOSE: To describe the use, tolerability, and efficacy of episcleral silicone matrix cyclosporine (ESMC) implants in dogs with keratoconjunctivitis sicca (KCS). METHODS: Retrospective study. ESMC implants (1.9 cm length, 30% wt/wt CsA in silicone; with approximately 12 mg of CsA loaded into them) were used in dogs with KCS responsive to topical CsA (good candidate, GC) or not responsive (poor candidate, PC). Ocular surface inflammation scores, Schirmer tear test (STT) values, and ocular discharge quantity were evaluated and compared. RESULTS: Twenty-seven eyes (15 dogs) received an ESMC implant for KCS; 15 eyes were considered GC, and 12 were considered PC. Both GC eyes and PC eyes showed a significant increase in STT values (increase of 7.7 and 8.5 mm/min; P = 0.023 and P = 0.003, respectively) after placement of ESMC implants (mean follow-up 18 ± 2 and 10.4 ± 15 months, respectively). Clinical signs improved significantly in both groups during the same follow-up, with reduction in conjunctival hyperemia (P < 0.001), corneal neovascularization (P = 0.004), corneal opacity (P = 0.003), and ocular discharge (P = 0.002). ESMC implants were well tolerated by all dogs, but two eyes lost the device at 12-months and 1-week follow-up, respectively. CONCLUSIONS: Results from this study suggest that the EMSC implants were well tolerated and efficacious in dogs with KCS responsive to topical CsA as well as dogs with poor response to topical therapy. Further study is needed to determine the duration of efficacy and optimal dose of CsA.

Effect of once daily topical 0.3% naltrexone on tear parameters and corneal sensitivity in dogs with uncontrolled keratoconjunctivitis sicca: a double-masked randomized placebo-controlled clinical trial.

OBJECTIVE: To determine the effect of once daily topical 0.3% naltrexone (NTX) on tear production, tear film breakup time (TFBUT), and corneal sensitivity in dogs with uncontrolled keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: Sixteen dogs with uncontrolled KCS. PROCEDURES: A randomized placebo-controlled trial was performed in 16 dogs with topical 0.3% NTX once daily or topical saline solution drops once daily. A baseline was obtained at week 0 for tear production (Schirmer tear test 1 and 2-STT1, STT2), TFBUT, and corneal sensitivity. STT1, STT2, and TFBUT were then subsequently measured at weeks 1, 2, and 4 while on NTX or saline drops. Corneal sensitivity measures were repeated at week 4. The drops were subsequently discontinued and all parameters rechecked at week 5. RESULTS: There was no statistically significant difference in tear parameters or corneal sensitivity between the NTX-treated and the saline-treated groups. CONCLUSION: Topical 0.3% NTX given as a once daily dose over 4 weeks did not alter tear production, tear film stability, or corneal sensitivity in dogs with uncontrolled KCS.