Canine neurogenic Keratoconjunctivitis sicca: 11 cases (2006-2010)

Subconjunctival liposomal sirolimus vs. cyclosporine or tacrolimus as treatment of keratoconjunctivitis sicca in dogs: A double-blind, randomized study

PURPOSE

To compare the safety and efficacy of a 100 microgram subconjunctival injection of liposome-encapsulated sirolimus (SCJS) to cyclosporine (CsA) or tacrolimus (CsA/T) for the treatment of keratoconjunctivitis sicca (KCS) in dogs.

METHODS

Dogs with signs and symptoms of KCS were block-randomized to one of two treatment groups: Biweekly SCJS or conventional treatment (CsA/T). Schirmer tear test 1 (STT-1) scores, conjunctival hyperemia (CH) scores, corneal opacity (CO) scores, and clinical evaluation of potential side effects were recorded every 2 weeks for 14 weeks for both groups. Differences between groups were analyzed using the mixed results ANOVA and U-Mann Whitney tests (p < .05 was considered significant).

RESULTS

A total of 30 eyes were included in the study, of which 20 eyes completed follow-up. There was no statistically significant interaction between the treatment group and time on STT-1 score (p = .165), and median CH and CO scores showed no statistically significant differences between groups (p = .353 and p = .393, respectively). There were no clinically significant side effects present in any subject at any time.

CONCLUSION

In this trial, a 1 mg/mL (100 micrograms) SCJS every 2 weeks showed similar safety and efficacy profiles as daily CsA/T in dogs with KS after 14 weeks of treatment. Larger studies should be performed to further assess SCJS as an alternative treatment for KCS.

Long-lasting otic medications may be a rare cause of neurogenic keratoconjunctivitis sicca in dogs

OBJECTIVE

To characterize the clinical course and long-term prognosis of a suspected novel cause of neurogenic keratoconjunctivitis sicca (nKCS) secondary to florfenicol, terbinafine hydrochloride, mometasone furoate (Claro and Neptra) or florfenicol, terbinafine, betamethasone acetate (Osurnia).

ANIMALS

29 client-owned dogs.

PROCEDURES

Online survey and word-of-mouth recruitment were conducted to identify dogs that developed clinical signs of nKCS after application of otitis externa medication containing terbinafine and florfenicol. A retrospective analysis of medical records of dogs meeting inclusion criteria was then conducted. Included dogs had onset of clinical signs of nKCS within 1 day after application of otitis externa medications containing terbinafine and florfenicol and had documentation of low Schirmer tear test value (< 15 mm/min) of affected eyes.

RESULTS

29 dogs with medical records available for review met the inclusion criteria. Documented return of clinically normal tear production was identified in 24 of 29 dogs, with a median time from application of ear medication to documented return of clinically normal tear production of 86 days (range, 19 to 482 days). A corneal ulcer was diagnosed in 68% (20/29). Multivariable Cox regression analysis showed being referred to an ophthalmologist (P = .03) and having a deep ulcer (P = .02) were associated with a longer time to documentation of Schirmer tear test ≥ 15 mm/min.

CLINICAL RELEVANCE

Dogs that developed nKCS within 1 day after application of otitis externa medications containing terbinafine and florfenicol had a good prognosis for return of normal tear production within 1 year.

Unilateral Dry Eye Due to Possible Isolated Parasympathetic Denervation of the Lacrimal Gland in a Woman With Hypothyroidism

PURPOSE

The aim of this study was to report a unique case of unilateral neurogenic dry eye disease (DED) secondary to isolated parasympathetic denervation of the lacrimal gland along with a literature review.

METHOD

This is a case report and literature review on neurogenic DED discussing its clinical presentation, etiology, and treatment options.

RESULTS

A 32-year-old woman with hypothyroidism presented with pain and a burning sensation in her left eye and dry nares for 1 week. Ocular examination revealed conjunctival congestion and inferior superficial punctate fluorescein staining in the left eye. Her unanesthetized Schirmer values were 24 and 01 mm in the right and left eyes, respectively, with no secretory activity noted in the left lacrimal gland on direct assessment. A detailed neurologic examination, autoimmune panel, and neuroimaging were unremarkable except for the dry left nasal cavity. She is currently using lubricants and did not consent to pilocarpine therapy. Her lacrimal gland activity was unchanged till 3 months of follow-up. The most common cause of neurogenic DED is idiopathic, followed by trauma. Pilocarpine therapy, in oral, topical, or combined form, has improved tear secretion in 63% of neurogenic DED seen in animal cohort.

CONCLUSIONS

Unilateral neurogenic DED can occur as an isolated parasympathetic denervation of the lacrimal glands. Pilocarpine therapy has shown some efficacy in animal cohort of neurogenic DED; however, it needs to be explored for human eyes.

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.

A retrospective evaluation of systemic and/or topical pilocarpine treatment for canine neurogenic dry eye: 11 cases

OBJECTIVE

To assess the response to topical and/or systemic pilocarpine in dogs with neurogenic dry eye.

METHOD

Medical records of dogs diagnosed with dry eye between 2015 and 2018 were reviewed. Cases were excluded if STT values were decreased bilaterally, if dogs were lost to follow-up, or if surgical measures (parotid duct transposition) were undertaken within thirty days of presentation. Dogs were on treatment with topical pilocarpine (0.1%, every 6 hours) and/or oral pilocarpine (starting dose 2%, one drop per 10 kg every twelve hours).

RESULTS

Eleven cases were included in the study, seven females and four males with mean age of 10 years. Seven cases had xeromycteria, two cases had facial nerve paralysis, and one case had Horner's syndrome. Seven cases (63.6%) had successful outcome following pilocarpine treatment, return to normal STT (15-25mm/minute), in an average of 24 ± 5.1 days. Of these cases, five had both systemic and topical treatment, one had just topical treatment, and one had just systemic treatment. The average time to normal tear production on treatment with topical pilocarpine ± systemic was 23 days (range 9-48 days). The number of systemic drops until a positive response varied between individuals from 0.8drops/10kg to 7drops/10kg.

CONCLUSION

Pilocarpine treatment (topical ± systemic) is an effective therapy for unilateral dry eye disease in cases suspected to be neurogenic in origin. Most cases responded within 30 days. Side effects included topical irritation to the ophthalmic solution and systemic effects from oral pilocarpine, such as diarrhea and regurgitation.

Clinical features of cats with aqueous tear deficiency: a retrospective case series of 10 patients (17 eyes)

OBJECTIVES

The aim of this study was to describe the clinical findings, diagnostic test results and response to therapy of cats with Schirmer tear test 1 (STT-1) values below the reference interval.

METHODS

The medical records of three institutions were searched for cats with ocular surface disease and STT-1 values <9 mm/min, confirmed at two or more separate visits.

RESULTS

Ten cats (17 eyes) were included. The mean ± SD (range) age and STT-1 values in affected eye(s) were 6.1 ± 5.7 (0.2-16) years and 2.4 ± 3.1 (0-8) mm/min, respectively. Concurrent ocular surface disease was bilateral in 5/10 cats. Clinical signs included conjunctivitis (14/17 eyes), corneal ulceration (6/17 eyes), non-ulcerative keratitis (4/17 eyes), symblepharon (4/17 eyes), eosinophilic keratitis (3/17 eyes), corneal sequestrum (3/17 eyes), corneal fibrosis (2/17 eyes) and meibomitis (2/17 eyes). Management included: topically applied lacrimomimetics, antiviral drugs, corticosteroids or immunomodulatory drugs; orally administered famciclovir; or surgical procedures, in various combinations. Response to therapy (defined as an increase in STT-1 value of ⩾5 mm/min) was transient (seen at a single reassessment) in 65% of eyes and sustained (seen at ⩾2 consecutive reassessments) in 18% of eyes.

CONCLUSIONS AND RELEVANCE

Clinical features seen in cats with low STT-1 values are described, although the association between aqueous deficiency and the reported ocular changes is unknown at this time. We encourage clinicians to assess the tear film in cats with ocular surface disease, and initiate therapy with lacrimomimetics if STT-1 values are repeatedly below normal. Such information will further define aqueous tear deficiency in cats, providing a better understanding of disease prevalence, pathogenesis and treatment.

Feline dry eye syndrome of presumed neurogenic origin: a case report

Case summary

A 14-year-old female spayed Abyssinian cat, which about 1 year previously underwent thoracic limb amputation, radiotherapy and chemotherapy for an incompletely excised vaccine-related fibrosarcoma, was presented for evaluation of corneal opacity in the left eye (OS). The ocular surface of both eyes (OU) had a lackluster appearance and there was a stromal corneal ulcer OS. Results of corneal aesthesiometry, Schirmer tear test-1 (STT-1) and tear film breakup time revealed corneal hypoesthesia, and quantitative and qualitative tear film deficiency OU. Noxious olfactory stimulation caused increased lacrimation relative to standard STT-1 values suggesting an intact nasolacrimal reflex. Various lacrimostimulants were administered in succession; namely, 1% pilocarpine administered topically (15 days) or orally (19 days), and topically applied 0.03% tacrolimus (47 days). Pilocarpine, especially when given orally, was associated with notable increases in STT-1 values, but corneal ulceration remained/recurred regardless of administration route, and oral pilocarpine resulted in gastrointestinal upset. Tacrolimus was not effective. After 93 days, the cat became weak and lame and a low thyroxine concentration was detected in serum. The cat was euthanized and a necropsy performed. Both lacrimal glands were histologically normal, but chronic neutrophilic keratitis and reduced conjunctival goblet cell density were noted OU.

Relevance and novel information

The final diagnosis was dry eye syndrome (DES) of presumed neurogenic origin, associated with corneal hypoesthesia. This report reinforces the importance of conducting tearfilm testing in cats with ocular surface disease, as clinical signs of DES were different from those described in dogs.

Caracterização clínica e histopatológica de bulbos oculares de cães e gatos (2005-2015)

RESUMO: Objetivou-se realizar a caracterização clínica e histopatológica de bulbos oculares de cães e gatos, removidos cirurgicamente por indicação clínica, no período entre 2005-2015. Foram realizados 101 procedimentos de remoção do bulbo ocular, 93 enucleações (92%) e 8 exenterações (8%). Os procedimentos foram realizados em 80 cães, (79% dos casos) e em 21 gatos (21% dos casos). Os cães submetidos à intervenção cirúrgica apresentavam perfurações oculares (n=31, 39%), glaucoma (n=19, 24%), protrusão ocular (n=13, 16%), diagnósticos sugestivos de neoplasia (n=10, 12,5%) e outros (n=3, 2,97%). Dentre os gatos os diagnósticos clínicos compreenderam perfuração ocular (n=9, 49%), glaucoma (n=3, 14,2%), microftalmia (n=3, 14,2%), sugestivo de neoplasia (n=2, 9,5%), protrusão ocular (n=2, 9,5%) e outros (n=2, 9,5%). Vinte e sete amostras de bulbos oculares foram submetidas para avaliação histopatológica, sendo 23 provenientes de cães e quatro de gatos. Dentre as amostras de origem canina, sete exibiram achados histopatológicos compatíveis com glaucoma, sete perfurações oculares, seis neoplasias intraoculares, duas panoftalmites e um quadro de Phthisis bulbi. Nos bulbos oculares de gatos foram diagnosticadas duas neoplasias intraoculares, uma microftalmia e uma perfuração ocular. Constatou-se que o glaucoma secundário, as neoplasias e as perfurações oculares estão entre as principais causas de enucleação em cães, e associadas a alterações primárias como a ceratoconjuntivite seca e as uveítes. Estas afecções, diferentemente das neoplasias, podem ter êxito terapêutico mediante diagnóstico e tratamento precoces, prevenindo a cegueira e a remoção do bulbo ocular.

Immune-mediated keratoconjunctivitis sicca in dogs: current perspectives on management

Keratoconjunctivitis sicca (KCS) is a frequent canine ophthalmic disease, resulting from the deficiency of one or more elements in the precorneal tear film. There are different known causes of KCS in dogs, including congenital, metabolic, infectious, drug induced, neurogenic, radiation, iatrogenic, idiopathic, and immune mediated, though the last one is the most prevalent form in dogs. Initially, clinical signs of KCS include blepharospasm caused by ocular pain, mucoid to mucopurulent ocular discharge, and conjunctival hyperemia; secondary bacterial infection may also occur, with chronicity, corneal epithelial hyperplasia, pigmentation, neovascularization, and corneal ulceration. The diagnosis of KCS is based on the presence of consistent clinical signs and measurement of decreased aqueous tear production using the Schirmer tear test. Therapy is based on administering the following topical drugs: ocular lubricant, mucolytics, antibiotics, corticosteroids, pilocarpine, and immunomodulators. These last drugs (eg, cyclosporine, pimecrolimus, and tacrolimus) have immunosuppressive activity and stimulate tear production. Furthermore, the nerve growth factor is a new subject matter of the research. Although these therapies are advantageous, stimulation of natural tear production seems to provide the highest recovery in clinical signs and prevention of vision loss. The goal of the following article is to describe the recent developments about KCS in dogs emphasizing the use of new therapies.

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.

Cholesteatoma and meningoencephalitis in a dog with chronic otitis externa

A 10-year-old female spayed German Shepherd dog, with a year-long history of recurrent left ear infections, was presented for progressive ataxia, head tilt, and pain on opening of the mouth. On physical examination, a large amount of ceruminous debris was present in the left ear and multiple neurologic defects localizing to the cerebellum and vestibular system were identified. Magnetic resonance imaging (MRI) demonstrated a minimally contrast-enhancing mass within the left bulla, an intracranial space-occupying, heterogeneously contrast-enhancing lesion at the level of the left cerebello-medullary junction, and contrast enhancement of the ipsilateral meninges. Cerebrospinal fluid analysis revealed a marked mixed cell pleocytosis (nucleated cell count 655 cells/μL). The mass was visualized within the horizontal ear canal by otoscopic examination and a biopsy was taken. Impression smears of the biopsy contained many anucleate keratinized squamous epithelial cells, mild mixed inflammation, and few presumptive fibroblasts. With the provided clinical history and MRI findings, a cytologic diagnosis of cholesteatoma was made. A ventral bulla osteotomy was performed, and histopathologic examination of resected tissue confirmed the cytologic diagnosis of cholesteatoma. The dog's clinical symptoms improved postoperatively, but the dog died of unrelated causes, 3.5 months later. To our knowledge, this is the first description of the cytologic features of a cholesteatoma, which is a nonneoplastic, but locally invasive epidermoid cyst, in the middle ear of dogs.