Management of Diplopia Indiana Optometric Association Annual Convention April 2018 Kristine B. Hopkins, OD, MSPH, FAAO

Transcription

1 Management of Diplopia Indiana Optometric Association Annual Convention April 2018 Kristine B. Hopkins, OD, MSPH, FAAO For patients with diplopia, the clinician must differentiate monocular from binocular diplopia. While management of monocular diplopia is not covered as part of this lecture, approximately 6-12% of patients presenting with diplopia symptoms will have monocular diplopia. Their symptoms may be described as ghosting, overlapping, or halos. The following are sources of monocular diplopia to consider: Sources of Monocular Diplopia Optical Organic Uncorrected astigmatic refractive error Neurogenic disease Reflections from lens surfaces Migraine Incorrect bifocal placement Epiretinal membrane Abnormalities of the tear film Choriodal neovascular membrane Corneal irregularity Macular edema Iris abnormalities Cataract or dislocated lens Optical causes of monocular diplopia may be differentiated from organic with the application of a pinhole. Organic etiology typically fail to resolve with pinhole while optical monocular diplopia typically disappears. (Rutstein, Vision Development and Rehabilitation July 2017) Management of binocular diplopia typically employs one of the treatment tools listed in the following table: Compensating Prism Prism Rx that fully corrects the strabismic angle (cover test = prism power). Rx BO for ET and BI for XT. Works best for comitant deviations with similar magnitude at distance and near (Basic Relieving Prism Yoked Prism Added Plus at near Prism Rx that partially corrects the strabismic angle. Rx the lowest amount of prism necessary to eliminate diplopia (use prism bars to gradually add or decrease power before deviated eye until diplopia is eliminated). Rx BO for ET and BI for XT. Prism Rx used to shift the patient s gaze away from a diplopic field of gaze. Rx is typically equal in magnitude for each eye with bases oriented in the same direction. The base direction is toward the Eso and Basic Exo). Works best for comitant deviations with similar magnitude at distance and near with some vergence reserves. Works best for incomitant deviations (alphabet patterns, LR palsy, TED) with a mild compensating head position that allows for fusion. diplopic gaze (the apex in the direction of the desired gaze). A bifocal Rx may be used for high AC/A eso deviations (convergence excess) with a low to moderate ET at near. Rx the lowest add needed to eliminate diplopia at near (up to +2.50). Kristine B. Hopkins, OD, MSPH, FAAO (kbhopkins@uab.edu) Page 1 of 5

2 Added Minus at distance Vision Therapy EOM Surgery Occlusion An over minus Rx may be helpful for young patients with high AC/A exo deviations (divergence excess) with a diplopic exotropia at distance. Rx the lowest amount of over minus needed to eliminate the exotropic diplopia. Younger patients (preschool) may tolerate up to but older patients (who are more likely to complain of diplopia) may not tolerate this treatment with diminishing accommodative amplitudes. Structured activities to improve the patient s compensating vergence ranges to control an intermittent strabismus. Emphasize BO training for exo s and BI training for eso s. Works best for small to moderate magnitude intermittent strabismus patients with fusion potential and some vergence reserves. This treatment requires active participation from the patient and is typically more effective on patients 6 years old and older. Surgical repositioning of the EOM s may be necessary for patients with large angle, high frequency strabismus deviations that cannot be successfully managed with other treatment modalities. Complete occlusion with a patch or attenuation with a Bangerter occlusion foil may be necessary for binocular diplopia that cannot be managed with other treatment options. It may also be useful for patients with intractable diplopia who cannot achieve binocular fusion. Suppression and ARC are common sensory adaptations found in young patients with high frequency strabismus with onset at a young age. Older patients who develop acute strabismus or whose strabismus decompensates (becoming larger and/or more frequent with age) are more likely to present with complaints of binocular diplopia. While the discussion of the presentation and management of every cause of binocular diplopia is not feasible for this presentation, this handout will provide a reference for some of the most common causes of diplopia. Comitant Exotropia Classification Symptoms Clinical Findings Treatment options Convergence Insufficiency IXT Diplopia with near work. May also have headaches, fatigue, and blur at near. Diplopia may be exacerbated with fatigue. Larger exo at near than distance. Reduced BO vergence ranges at near. Receded NPC (<6cm) Often also have accommodative insufficiency. 1) Vision therapy (emphasizing BO training); in office or home based 2) BI Prism readers (more effective for presbyopes). Consider using Sheard s criteria for prism Rx: 2/3(phoria) 1/3 (BO Break at near) 3) May consider surgery for large angle, high frequency XT 4) May consider occlusion or attenuation (Bangerter foil) over reading portion of lenses Kristine B. Hopkins, OD, MSPH, FAAO (kbhopkins@uab.edu) Page 2 of 5

3 Divergence Excess IXT Rarely diplopic if onset at a young age. Decompensated XP/IXT at distance at an older age may experience diplopia at distance (driving). May report photophobia and/or squinting. Larger exo at distance than near. BO vergences may be reduced or normal. 1) Over minus (-2.00 to -3.00) for very young patients (preschool) with high AC/A 2) Vision Therapy for moderate angle less frequent XT 3) Surgery for large angle, high frequency XT 4) May consider monocular occlusion for driving if other treatments not pursued. Prism typically not helpful since the deviation is often moderate to large at distance and small at near. Comitant Esotropia Classification Symptoms Clinical Findings Treatment Options Divergence Insufficiency ET Convergence Excess ET Diplopia at distance if adult onset (young ET patients typically do not have dip) Diplopia at near (reading and computer work). Very young patients are rarely diplopic. Small to moderate eso at distance with reduced divergence reserves. More common in patients >50yo due to changes in EOM structure. MUST CONFIRM NORMAL ABDUCTION TO RULE OUT CNVI PALSY. Larger eso at near than at distance. Reduced BI reserves at near. 1) BO prism (the smallest magnitude that eliminates dip at distance). Confirm that this is tolerated at near. May consider Fresnel for distance only. 2) Surgery for moderate to larger ET s (>15^) 3) May consider VT for small angle intermittent eso s. 4) May consider occlusion or Bangerter foils if other treatment not pursued. Consider Myasthenia, Thyroid Eye Disease, and CNVI palsy as differentials for older patients. Consider accommodative/convergence spasm in younger patients. 1) Additional plus at near (reading Rx or bifocal) to decrease accommodative demand and reduce Eso. 2) BO prism in addition to near plus for residual eso (<10Δ). May consider Fresnel overlapping the add if BO not tolerated at distance. May consider a separate reading Rx with plus and BO prism. 3) Surgery for large angle residual esotropia Consider accommodative/convergence spasm as a differential diagnosis. Kristine B. Hopkins, OD, MSPH, FAAO (kbhopkins@uab.edu) Page 3 of 5

4 Incomitant strabismus may be congenital or acquired. Congenital etiologies include congenital cranial nerve palsies and abnormal extra ocular muscle anatomy. Congenital etiologies may result in a compensatory head position to avoid diplopia. Acquired incomitant deviations include supranuclear lesions (not covered here), cranial nerve palsies, thyroid eye disease, myasthenia, trauma, and others. For small deviations, these patients may also assume a compensatory head position. The following table summarizes the clinical findings and treatment options for some of the more common etiologies of incomitant strabismus. Incomitant Strabismus Classification Symptoms Clinical findings Treatment Options Alphabet Pattern Strabismus Lateral Rectus (CNVI) Palsy Superior Oblique (CNIV) Palsy May report diplopia that changes with up and/or down gaze. Many patients with alphabet pattern deviations do not report diplopia but may be bothered by an abnormal head posture. Diplopia with gaze toward affected side. May also report uncrossed diplopia at distance with fusion at near. May report vertical diplopia in primary gaze that worsens with adduction of the affected eye. May report abnormal head posture to keep fusion. Esotropia or Exotropia that changes from up to down gaze. May also see over/under action of elevators and depressors on EOM testing. May see compensatory head position (chin up or down). Increased esotropia with gaze to affected side (limited abduction of affected eye). Divergence insufficiency ET (ET at distance, fusion at near). Hypertropia of affected eye that worsens with adduction and head tilt toward affected side. May also exhibit excyclotorsion. 1) Yoked prism to aid with abnormal head position. To reduce CHIN UP posture, Rx yoked BASE UP To reduce CHIN DOWN posture, Rx yoked BASE DOWN Trial prism in office and Rx least amount to affect head posture (upper limit 6-8Δ ground prism for each eye, may Rx higher prism as Fresnel). 2) Consider surgery for large magnitude strabismus and/or exaggerated head posture. Ischemic etiology may resolve spontaneously over the course of several months. Manage diplopia with Fresnel, Bangerter, or occlusion and monitor for resolution. For longstanding, stable CNVI palsy, consider this: 1) Base out prism to eliminate diplopia at distance for ET <15Δ (least amount necessary; may grind up to 6-8ΔBO each eye or apply Fresnel for larger deviations). 2) Fresnel BO prism over distance portion of lenses for larger deviations. 3) Surgery for larger symptomatic deviations. Ischemic etiology may resolve spontaneously over the course of several months. Manage diplopia with Fresnel, Bangerter, or occlusion and monitor for resolution. For longstanding, stable CNIV palsy, consider these: Kristine B. Hopkins, OD, MSPH, FAAO (kbhopkins@uab.edu) Page 4 of 5

5 Ocular Motor Nerve (CNIII) Palsy Thyroid Eye Disease Ptosis is typically present which may occlude the pupil and prevent diplopia. If ptosis is mild, patient may report constant diagonal diplopia. Double vision, often vertical and worse in specific gaze positions. Ptosis with hypotropia and exotropia of the affected eye. Limited motility of affected eye. Ischemic etiology is typically pupil sparing. Non-traumatic CNIII that involves the pupil has high probability of tumor or aneurysm etiology (immediate ED referral). 90% with lid retraction 40% with EOM involvement (restricted motilities, often limited elevation) and diplopia. 6% with ONH dysfunction (ONH compression) 1)BASE DOWN (relieving) prism on affected (hyper) eye. Rx the least amount necessary to eliminate diplopia. For larger prism amounts, consider Fresnel. 2)May consider yoked BASE DOWN prism for patients who notice more diplopia in down gaze. 3)Bangerter foil to blur the diplopic image 4)Surgery for larger symptomatic deviations Prism typically of little help due to the extreme incomitance of this deviation. Treatment typically palliative (occlusion or Bangerter) for acute palsy. For longstanding palsy, surgical consult is typically recommended. 1) Relieving prism before the affected eye to eliminate diplopia in primary gaze. Do not split prism. Rx full prism amount before the affected eye. May use Fresnel for larger deviations. 2) Yoked prism to move eyes away from affected gaze (base should be oriented toward affected field). 3) Occlusion or Bangerter to eliminate or attenuate diplopic image 4) Orbital decompression surgery for more severe motility restriction. Consider lubrication for corneal dryness often associated with lid retraction. Kristine B. Hopkins, OD, MSPH, FAAO Page 5 of 5