NAVLE Ophthalmology: Key Diseases and Examination Techniques

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-11

Key Takeaways

• Neuro-ophthalmic reflexes (menace, palpebral, dazzle, pupillary light reflex) are critical for localizing lesions to specific cranial nerves (II, III, VII) or brainstem structures, aiding in differential diagnosis for visual and motor deficits.
• The Schirmer tear test, performed before topical application of solutions, quantifies basal and reflex tear production (normal canine values typically 15-25 mm/min) to diagnose keratoconjunctivitis sicca, while fluorescein staining identifies corneal epithelial defects, differentiating ulcerative from non-ulcerative keratitis.
• Intraocular pressure (IOP) measurement via tonometry (normal canine IOP ~10-25 mmHg) is essential for distinguishing uveitis (hypotony) from glaucoma (hypertension), with gonioscopy used to assess the iridocorneal angle for glaucoma risk.
• Corneal ulceration, particularly melting ulcers driven by bacterial collagenase, requires immediate antimicrobial therapy and potentially adjunctive antiprotease treatment (e.g., serum, EDTA), with referral indicated for deep ulcers (>50% stromal depth) or descemetoceles.
• Anterior uveitis necessitates a minimum database including CBC, serum chemistry, and infectious disease testing (serology/PCR) to identify underlying causes such as FeLV/FIV, Toxoplasma, Bartonella, Ehrlichia, or fungal infections, and glaucoma must be excluded prior to mydriatic therapy.
• Progressive retinal atrophy (PRA) is characterized by nyctalopia and fundic changes like tapetal hyperreflectivity and vascular attenuation, confirmed by electroretinography, while sudden acquired retinal degeneration syndrome (SARDS) causes acute blindness with initially normal fundic appearance but absent ERG responses.

This article reviews the ocular diseases and examination techniques most frequently tested on the NAVLE, with a cross-species emphasis. It is written for veterinary students preparing for board certification and assumes familiarity with basic ocular anatomy and clinical terminology. The content focuses on diagnostic reasoning, lesion recognition, and disease classification instead of surgical management. For official information on examination structure, content domains, and candidate eligibility, consult the ICVA NAVLE candidate information.

The NAVLE assesses clinical decision-making across species, and ophthalmology questions commonly appear in the context of general practice presentations. This reference organizes the material by examination technique, then by disease category, with attention to the distinguishing features that separate one condition from its differentials. Where the evidence base is limited or contested, that uncertainty is stated explicitly.

At a Glance

Examination Technique Principles

The ophthalmic examination follows a logical sequence that minimizes artifact and maximizes information yield. Begin with distant observation in a well-lit room, assessing palpebral fissure symmetry, globe position, and ocular discharge before handling the patient. Perform the neuro-ophthalmic examination next, as manual restraint and topical anesthesia can alter reflex responses.

The menace response tests the visual cortex and CN II afferent pathway, but it is a learned response that may be absent in puppies and kittens under 10 to 12 weeks of age. The dazzle reflex, by contrast, is subcortical and present from birth. The palpebral reflex assesses CN V afferent and CN VII efferent function. The pupillary light reflex evaluates CN II and CN III, and a consensual response requires an intact optic chiasm and oculomotor nucleus. In animals with a fixed dilated pupil, distinguish between CN III palsy, iris atrophy, and pharmacologic mydriasis before concluding the lesion is neurologic.

The Schirmer tear test should be performed before any topical solutions are applied, as fluorescein and proparacaine can suppress tear production. The test measures basal and reflex tearing over one minute. Values below 10 mm/min in dogs are consistent with keratoconjunctivitis sicca, though clinical signs and tear film breakup time provide supporting evidence. The MSD Veterinary Manual provides species-specific reference ranges and interpretive guidance for tear testing.

Fluorescein staining detects corneal epithelial defects. Apply the stain, rinse with saline, and examine under cobalt blue light. A positive stain indicates ulceration. The stain also confirms a patent nasolacrimal duct when it appears at the ipsilateral nostril, though false negatives occur in brachycephalic breeds with aberrant drainage. Rose bengal stains devitalized epithelium and is useful for early keratoconjunctivitis sicca and feline herpesvirus keratitis, where fluorescein may be negative.

Tonometry is performed after fluorescein staining and before mydriatics. Applanation tonometry is standard in practice, while rebound tonometry is increasingly common and better tolerated in small patients. The normal IOP range for dogs and cats is approximately 10 to 25 mmHg. A single elevated reading warrants repeat measurement, as restraint and corneal compression can produce artifact. Gonioscopy requires a specialized lens and is indicated when glaucoma is suspected or when assessing breed predisposition to angle closure.

Ocular Pharmacology Basics

Mydriatics and cycloplegics are essential for fundic examination and for treating uveitis. Atropine produces prolonged mydriasis and cycloplegia, but it is contraindicated in glaucoma and should be used cautiously in animals with shallow anterior chambers. Tropicamide provides short-duration mydriasis suitable for routine fundoscopy. Phenylephrine is a sympathomimetic mydriatic that does not cause cycloplegia and is useful when pupillary mobility must be preserved.

Topical anesthetics such as proparacaine are diagnostic tools only. They are never prescribed for home use because they inhibit corneal epithelial mitosis and delay healing. Their use in the examination room facilitates tonometry, foreign body removal, and corneal sampling.

Corticosteroids are contraindicated in the presence of corneal ulceration because they potentiate collagenase activity and delay epithelialization. This principle governs the initial management of any red eye: stain before treating. The distinction between ulcerative and non-ulcerative keratitis determines whether anti-inflammatory therapy is safe.

Anatomy and Physiology Relevant to Disease

The cornea has five layers in dogs and cats: epithelium, stroma, Descemet membrane, and endothelium, with the basement membrane integrated into the epithelium. The stroma comprises 90 percent of corneal thickness. When stromal loss occurs, the cornea becomes opaque due to disruption of the regular collagen lattice and subsequent edema. Deep ulcers approaching Descemet membrane carry a high risk of perforation and require urgent referral.

The anterior chamber angle drains aqueous humor through the trabecular meshwork into the scleral venous plexus. Obstruction of this outflow pathway raises IOP and produces glaucoma. In dogs, primary glaucoma is often breed-associated and frequently bilateral, even when clinical signs are initially unilateral. The AVMA practice resources address breed-specific health screening recommendations that inform glaucoma risk assessment.

The retina is supplied by the choroidal circulation in most species, with the exception of the holangiotic retina in dogs and cats, which has a central retinal artery. Retinal detachment separates the neurosensory retina from the retinal pigment epithelium, and the resulting hypoxia causes rapid photoreceptor degeneration. The time between detachment and reattachment determines the likelihood of visual recovery.

Common Ocular Diseases by Anatomic Region

Adnexal and Orbital Disease

Blepharitis presents with erythema, alopecia, crusting, and pruritus of the eyelid margins. Infectious causes include staphylococcal pyoderma, dermatophytosis, and demodicosis. Immune-mediated forms, such as discoid lupus erythematosus and pemphigus foliaceus, often produce depigmentation and crusting that begins at the mucocutaneous junction. Distinguish primary blepharitis from blepharospasm secondary to corneal pain by performing a complete fluorescein stain before treating empirically.

Entropion and ectropion represent opposing conformational failures. Entropion, inward rolling of the eyelid margin, causes trichiasis and secondary corneal ulceration. It occurs as a primary conformational defect in brachycephalic dogs, Shar-Peis, and several sheep breeds, or as a secondary spastic response to ocular pain. Ectropion, outward rolling, predisposes to exposure keratitis and conjunctivitis, particularly in hounds and giant breeds. Surgical correction is the definitive treatment for both, but temporary tacking sutures or medical lubrication may stabilize acute cases pending surgery.

Orbital cellulitis and orbital abscess share clinical features: unilateral exophthalmos, fever, pain on opening the mouth, and resistance to retropulsion. Differentials include orbital neoplasia, zygomatic sialadenitis, and extraocular myositis. Diagnostic imaging, preferably computed tomography, distinguishes focal abscess from diffuse cellulitis or mass lesion. Abscess drainage via the oral cavity or temporal fossa is indicated when a discrete pocket is identified. Extraocular myositis, an immune-mediated condition of young large-breed dogs, produces bilateral exophthalmos with pain on opening the mouth and responds to immunosuppressive glucocorticoid therapy.

Corneal and Anterior Segment Disease

Corneal ulceration is the most common ophthalmic emergency in small animal practice. Uncomplicated superficial ulcers heal by epithelial migration within three to seven days. Indolent ulcers, common in boxers and other brachycephalic breeds, fail to epithelialise because of a nonadherent epithelial edge. They are identified by loose epithelium that stains irregularly and by a lack of vascularisation. Grid keratotomy or diamond burr debridement is the standard treatment, combined with a protective contact lens or temporary tarsorrhaphy.

Melting ulcers, characterized by stromal liquefaction and a gelatinous appearance, require aggressive therapy. Collagenase-producing bacteria, particularly Pseudomonas species, and proteolytic enzymes from neutrophils drive stromal destruction. Topical antimicrobial therapy must be initiated immediately, and serum or ethylenediaminetetraacetic acid may be used as adjunctive antiprotease treatment. Refer for surgical intervention when the ulcer exceeds 50 percent stromal depth or when descemetocele is present.

Feline herpesvirus-1 is the leading cause of corneal disease in cats. Dendritic ulcers, best visualized with rose bengal stain, are pathognomonic. Eosinophilic keratitis produces raised, white to pink plaques with superficial vascularisation and is diagnosed cytologically by the presence of eosinophils and mast cells. Corneal sequestration presents as a brown to black plaque of necrotic stroma, most often in brachycephalic breeds. Medical management with antiviral or anti-inflammatory therapy may control early cases, but surgical removal is frequently required for sequestration.

Anterior uveitis produces miosis, aqueous flare, hypotony, and ciliary flush. Causes include trauma, infectious agents such as feline leukemia virus, feline immunodeficiency virus, Toxoplasma gondii, and Bartonella species in cats, and immune-mediated disease. In dogs, common infectious causes include Ehrlichia, Rickettsia, Brucella canis, and fungal organizms such as Blastomyces and Histoplasma. A minimum database for uveitis should include complete blood count, serum chemistry, and infectious disease serology or polymerase chain reaction testing based on regional prevalence. Glaucoma must be excluded by tonometry before initiating mydriatic therapy.

Lens and Vitreous Disease

Cataracts are classified by age of onset, location, and stage of maturation. Inherited cataracts are common in many purebred dogs, including the Labrador Retriever, Golden Retriever, and Siberian Husky. Metabolic cataracts occur with diabetes mellitus, where rapid onset of bilateral cataract is typical. Traumatic cataracts may follow blunt or penetrating injury. The decision to refer for phacoemulsification depends on visual status, patient age, concurrent ocular disease, and owner expectations. Preoperative electroretinography and ocular ultrasound are required when the fundus cannot be visualized.

Lens luxation, anterior or posterior, occurs when the zonular fibers degenerate. Primary luxation is inherited in terrier breeds, particularly the Jack Russell Terrier and Tibetan Terrier. Secondary luxation follows chronic glaucoma, cataract, or trauma. Anterior luxation is an emergency because it obstructs aqueous outflow and rapidly elevates intraocular pressure. Posterior luxation may be managed medically with miotic therapy, whereas anterior luxation requires surgical removal or referral.

Glaucoma

Glaucoma is defined by progressive optic neuropathy associated with elevated intraocular pressure. Primary glaucoma is inherited in breeds including the Basset Hound, Cocker Spaniel, and Samoyed. Secondary glaucoma follows uveitis, intraocular neoplasia, lens luxation, or trauma. Tonometry is essential for diagnosis, with normal canine intraocular pressure ranging from 10 to 25 mmHg. Gonioscopy, when available, identifies the drainage angle conformation and helps predict risk in the fellow eye.

Medical therapy aims to reduce aqueous production or increase outflow. Carbonic anhydrase inhibitors, beta-blockers, and prostaglandin analogues are the mainstays. Prostaglandin analogues are contraindicated in uveitic glaucoma because they exacerbate inflammation. Emergency treatment of acute angle-closure glaucoma requires rapid reduction of intraocular pressure, often with hyperosmotic agents, followed by long-term maintenance therapy. Surgical options, including cyclophotocoagulation and drainage implants, are reserved for refractory cases. The contralateral eye of a patient with primary glaucoma is at high risk and warrants prophylactic therapy.

Posterior Segment Disease

Retinal Disease

Progressive retinal atrophy encompasses a group of inherited photoreceptor degenerations. Rod-cone degeneration presents with nyctalopia progressing to complete blindness, and fundic examination reveals tapetal hyperreflectivity, vascular attenuation, and optic nerve pallor. Electroretinography confirms the diagnosis before fundic changes are visible. Sudden acquired retinal degeneration syndrome causes acute blindness with mydriasis and absent pupillary light reflexes, yet the fundus appears normal initially. Diagnosis is confirmed by electroretinography showing absent or markedly reduced responses.

Retinal detachment may be rhegmatogenous, tractional, or exudative. Hypertension is the leading cause in cats, often secondary to chronic kidney disease or hyperthyroidism. Systemic hypertension also causes retinal hemorrhage and edema. Blood pressure measurement is mandatory in any cat with acute blindness or retinal detachment. Chorioretinitis in dogs is frequently associated with systemic mycoses, ehrlichiosis, or toxoplasmosis. The characteriztic lesion is a focal area of hyporeflectivity or hyperreflectivity with variable pigmentation.

Optic Nerve Disease

Optic neuritis produces acute blindness with dilated, nonresponsive pupils. The optic disc appears swollen and may be hemorrhagic. Differentials include immune-mediated disease, neoplasia, and infectious causes. Optic nerve hypoplasia is a congenital condition causing blindness with small, pale optic discs. Distinguish optic neuritis from sudden acquired retinal degeneration syndrome by fundic examination and electroretinography, which is normal in optic neuritis but abnormal in retinal disease.

Diagnostic Decision Table

Species-Specific Considerations

Horses present unique challenges. Equine recurrent uveitis is the leading cause of blindness and produces recurrent episodes of uveitis with miosis, photophobia, and corneal edema. Leptospiral infection is a recognized trigger in some regions. Treatment combines topical and systemic anti-inflammatory therapy with mydriatics to prevent synechiae. Equine glaucoma is often secondary to uveitis and may be managed medically, though response is variable.

Cattle and small ruminants require consideration of production context. Infectious bovine keratoconjunctivitis, caused by Moraxella bovis, is the most common ocular disease in cattle and is associated with ultraviolet light exposure and face flies. Treatment includes topical or subconjunctival antibiotics and isolation of affected animals. Ovine contagious ophthalmia, caused by Mycoplasma conjunctivae, produces conjunctivitis and keratitis and is highly contagious within flocks. The WOAH terrestrial animal health standards address surveillance and trade implications for certain ocular diseases with production impact.

Avian and exotic species require adapted examination techniques. Birds have a rigid scleral ossicle ring, limiting globe retropulsion. Rabbits have a large globe with a thin cornea and are prone to exophthalmos from retrobulbar disease, particularly abscessation. The fundus of rabbits is merangiotic, with retinal vessels confined to a horizontal band. Reptiles may present with retained spectacles after shedding, which predispose to subspectacular abscessation.

Documentation and Monitoring

Ophthalmic examination findings must be recorded systematically. Document each structure separately, noting laterality, severity, and progression. Serial tonometry is essential for glaucoma monitoring, with measurements taken at the same time of day when possible. Schirmer tear test values should be tracked in keratoconjunctivitis sicca to assess response to immunomodulatory therapy. Photographic documentation is valuable for tracking corneal ulcers, retinal lesions, and tumor progression.

Recheck intervals depend on disease severity. Simple corneal ulcers require recheck in three to five days. Melting ulcers may require daily rechecks. Glaucoma patients are typically rechecked within one to two weeks of initiating therapy, then at increasing intervals once intraocular pressure is controlled. Uveitis patients are rechecked within one week to assess response and adjust anti-inflammatory therapy. The MSD Veterinary Manual provides species-specific guidance on monitoring parameters and expected response timelines for common ocular conditions.

Referral criteria should be established early. Immediate referral is indicated for anterior lens luxation, descemetocele, corneal perforation, and glaucoma unresponsive to medical therapy. Equine recurrent uveitis and feline corneal sequestration often benefit from early specialty evaluation. The AVMA practice resources offer guidance on building referral relationships and communicating effectively with specialty colleagues.

Recognized Complications and Early Detection

Ocular disease progression follows recognizable failure modes. Early detection depends on repeated examination with a consistent protocol, not on a single dramatic finding.

Corneal ulceration complicated by infection is the most common avoidable escalation. A superficial ulcer that develops a yellow-white infiltrate, stromal malacia, or rapid deepening within 24 to 48 hours indicates bacterial protease activity. Recheck every 24 hours until epithelialisation begins. A melting cornea requires immediate intervention, the diagnosis is clinical, supported by cytology showing degenerate neutrophils and bacteria.

Uveitis that fails to respond to anti-inflammatory therapy within 72 hours should prompt reconsideration of the diagnosis. Lymphoma, fungal disease, and lens-induced uveitis can mimic classic anterior uveitis. Repeat the complete examination, including gonioscopy if glaucoma is suspected, and evaluate the contralateral eye for asymmetry.

Glaucoma misclassification is a recurring failure. Primary glaucoma in dogs is bilateral and progressive, the contralateral eye requires prophylactic therapy even when pressures are normal. Secondary glaucoma demands identification of the inciting cause, such as lens luxation, intraocular neoplasia, or chronic uveitis. Tonometry readings that conflict with clinical signs warrant repeat measurement under consistent conditions, as artefactually high readings occur with corneal edema or patient resistance.

Cataract assessment errors typically involve underestimating the stage of maturity. A hypermature cataract can appear less dense than a mature cataract because cortical resorption clears the lens. Examine the fundus through the clear peripheral lens, if the tapetal reflection is absent, assume the cataract is functionally mature and plan accordingly.

Retinal detachment detected on ultrasound may be rhegmatogenous, tractional, or exudative. The distinction matters for prognosis and therapy. Serial ultrasound examinations documenting progression or reattachment provide the most objective monitoring data.

Common Errors and Corrective Actions

Students and early-career clinicians repeat several predictable errors. The most consequential is incomplete examination due to patient discomfort. Sedation or topical anesthesia is not optional when the eye is painful, struggling produces iatrogenic corneal injury and unreliable measurements.

Fluorescein application before other diagnostics contaminates the tear film and interferes with Schirmer tear testing. Perform tear testing first, then fluorescein, then tonometry. This sequence preserves the validity of each test.

Mydriasis before fundic examination is appropriate, but tropicamide administration before tonometry invalidates the pressure reading. Tonometry precedes dilation.

The menace response is frequently misinterpreted. A positive menace requires a blink without corneal stimulation or air movement. Many patients blink to the visual threat of an approaching hand, not to the movement itself. Test each eye separately while covering the contralateral eye, and compare with the palpebral reflex to distinguish vision from tactile response.

Pupillary light reflex assessment in the presence of iris atrophy or synechiae produces false-negative results. Document the iris abnormalities and interpret the reflex cautiously.

Limitations of the Evidence

The evidence base for veterinary ophthalmology is uneven. Canine glaucoma and cataract literature is comparatively robust, while feline and exotic species ophthalmology relies heavily on case series and expert opinion. Medical therapy for glaucoma in cats is extrapolated from canine data with limited pharmacokinetic validation. Equine recurrent uveitis treatment protocols vary substantially between institutions, and comparative trials are scarce.

Expert opinion differs on several practical points. The role of prophylactic cyclosporine in canine keratoconjunctivitis sicca remains debated, with some authorities advocating early intervention and others reserving it for confirmed tear deficiency. The timing of cataract surgery in diabetic dogs is similarly contested, particularly regarding optimal glycaemic control before surgery. Routine enucleation versus evisceration with prosthesis for blind painful eyes generates ongoing discussion, with outcomes dependent on case selection.

The MSD Veterinary Manual provides species-specific guidance that reflects current consensus, but practitioners should recognize that consensus does not equal certainty. Where evidence is limited, document the reasoning behind therapeutic choices and revisit them if the clinical course diverges from expectations.

Referral and Escalation Criteria

Referral is indicated when diagnostic capability or therapeutic resources are exhausted. Immediate referral is warranted for corneal perforation, descemetocele, acute glaucoma unresponsive to initial therapy, suspected intraocular neoplasia, and any orbital disease with visual or systemic compromise. Progressive retinal disease with sudden blindness warrants referral for electroretinography and genetic testing where available.

Specialist consultation is appropriate for chronic uveitis of unknown cause, recurrent corneal ulcers, and cataracts in animals with concurrent ocular disease. The AVMA practice resources offer guidance on referral communication and documentation standards that support continuity of care.

Laboratory involvement is required for suspected systemic disease. Fungal serology or culture for endemic mycoses, Toxoplasma titres in feline uveitis, and blood pressure measurement for hypertensive retinopathy are standard investigations. Cytology of aqueous humour or vitreous aspirates should be performed only where the laboratory can process samples immediately and where the risk-benefit analysis supports the procedure.

Regulatory reporting applies to notifiable diseases. Equine recurrent uveitis is not reportable, but vesicular stomatitis and other vesicular diseases affecting the periocular region are. The WOAH terrestrial animal health standards list diseases requiring international notification, and national authorities may impose additional reporting requirements. Suspected foreign animal diseases involving ocular signs should be reported immediately to the relevant veterinary authority.

The ICVA NAVLE candidate information describes the examination content areas that include ophthalmology, and candidates should be prepared to apply escalation and referral reasoning in clinical scenarios. Knowing when to refer is as important as knowing how to treat.

Frequently Asked Questions

How do I perform a meaningful ophthalmic examination when I only have a penlight and an otoscope?

A penlight and otoscope can still yield a structured examination. Use the penlight for the menace response, dazzle reflex, pupillary light reflexes, and to assess the anterior chamber for flare or hyphema. The otoscope head, held close to the eye, provides magnification and a focused light source for examining the cornea, iris, and anterior lens. Assess the fundic reflection by holding the otoscope at arm's length and looking for a tapetal reflection. If the reflection is absent, consider media opacity or retinal detachment. Document exactly what you could and could not evaluate, and refer when the fundus cannot be visualized. The MSD Veterinary Manual describes these basic techniques as part of the standard ophthalmic examination.

What is the minimum equipment I should request for a general practice ophthalmology kit?

A focused kit includes a Finoff transilluminator, a direct ophthalmoscope, fluorescein strips, a cobalt blue filter, topical proparacaine, tropicamide, a Schirmer tear test strip, and a tonometer. The TonoVet or Tono-Pen is the single most valuable addition because tonometry distinguishes glaucoma from uveitis, two conditions that share a red, painful eye but require opposite treatments. A magnifying loupe or head loupe improves corneal and anterior segment assessment. Practice with the direct ophthalmoscope on normal eyes until you can reliably identify the optic nerve head and retinal vessels. The AVMA practice resources offer guidance on building diagnostic capacity in general practice settings.

How should my diagnostic approach change when examining a horse versus a dog with an opaque cornea?

The horse requires more caution. A cloudy cornea in a horse is an emergency until proven otherwise, as fungal keratitis can progress rapidly and perforate within 24 to 48 hours. Perform fluorescein staining and obtain cytology early. Sedation and auriculopalpebral nerve blocks are often necessary for a complete examination. In dogs, corneal opacity more commonly reflects ulcerative keratitis, pigmentary keratitis, or endothelial degeneration, and the pace of workup can be slower. Always assess for concurrent uveitis in both species, but note that horses with corneal ulcers frequently develop reflex uveitis that requires atropine and anti-inflammatory therapy. The MSD Veterinary Manual provides species-specific guidance on corneal disease presentation and management.

What should I record in the medical record after an ophthalmic examination?

Record the neuro-ophthalmic reflexes separately from the ocular examination. Note menace response, palpebral reflex, dazzle reflex, and both direct and consensual pupillary light reflexes for each eye. Document Schirmer tear test values, fluorescein retention, intraocular pressure, and whether tonometry was performed before or after mydriasis. Describe lesions by location, size, and depth using a clock-face reference. Include a sketch or photograph when possible. Record the owner's observations about vision loss, discharge, or pain, and note whether the findings are unilateral or bilateral. This structure supports serial comparisons and defensible referral communication. The ICVA NAVLE Candidate Information emphasizes documentation skills as part of the competencies assessed on the examination.

How do I explain a referral decision to a client who is concerned about cost?

Frame the referral as a diagnostic and therapeutic investment, not a failure of primary care. State clearly what you have ruled out and what remains uncertain. For example, explain that you have confirmed a corneal ulcer but cannot determine whether it is infected or melting without cytology and culture. Give the client a specific list of procedures the ophthalmologist will likely perform and a realistic range of costs, acknowledging that the range varies by region and facility. Offer a staged plan: emergency stabilization in your practice, followed by referral if the eye does not improve within 48 hours. The AVMA practice resources include guidance on client communication and financial discussions in veterinary practice.

When is it acceptable to manage a suspected glaucoma case medically without immediate referral?

Medical management is acceptable when the intraocular pressure is moderately elevated, the eye is visual, and the owner can commit to frequent rechecks. Start with a prostaglandin analogue and a carbonic anhydrase inhibitor, then recheck pressure within 24 hours. If pressure does not drop below 25 mmHg, referral is indicated. If the eye is blind and painful, enucleation or referral for salvage procedures should be discussed promptly. Never use topical corticosteroids in a glaucomatous eye, and never use atropine. Monitor for signs of systemic absorption of topical beta-blockers, especially in small dogs and cats with cardiac disease. The MSD Veterinary Manual outlines the medical options and monitoring parameters for canine glaucoma.

Related Clinical & Scientific Guides

• Developing a Study Schedule for NAVLE Diagnostic Reasoning
• Veterinary Physiology Concepts Frequently Tested on the NAVLE
• NAVLE Clinical Rotation Preparation: What to Review Before Each Service

References and Further Reading

• ICVA NAVLE Candidate Information. ICVA.
• AAVMC Veterinary Education Resources. AAVMC.
• MSD Veterinary Manual, Professional Edition. MSD Veterinary Manual.
• American Veterinary Medical Association Practice Resources. American Veterinary Medical Association.
• WOAH Terrestrial Animal Health Code. WOAH.

Related Articles

• NAVLE Immunology: Key Concepts and Clinical Applications
• NAVLE Anesthesia and Analgesia Review
• Veterinary Neurology for the NAVLE: Key Concepts
• NAVLE Study Resources: A Comparative Review
• Veterinary Clinical Pathology for the NAVLE: Key Concepts

This article is educational professional reference material for veterinary audiences. It is not a substitute for veterinary diagnosis, individual clinical judgment, current product labeling, or applicable regulatory requirements.