What is the recommended treatment approach for vertical diplopia?

Treatment of Vertical Diplopia

The treatment of vertical diplopia depends critically on the underlying etiology and should follow a stepwise approach: immediate observation with prism therapy for acute cases awaiting spontaneous resolution, followed by definitive surgical correction for persistent deviations after 6 months of stability. 1

Initial Management Strategy

Acute Phase (First 6 Months)

Observation is mandatory when the deviation is not yet stable or when signs of active inflammation persist. 1 The specific observation period depends on etiology:

• Vasculopathic causes (diabetes, hypertension, hyperlipidemia): Most resolve spontaneously within 6 months, with approximately one-third resolving within 8 weeks 1
• Thyroid eye disease: Requires stability for at least 4-6 months before surgical intervention 1
• Vestibular neuronitis: Often self-limiting and may respond to medical intervention 1

Symptomatic Relief During Observation

Prism therapy provides temporary diplopia control while awaiting spontaneous resolution or surgical candidacy. 1 Options include:

• Fresnel prisms for temporary relief and easy adjustment 1
• Ground-in prisms for small to moderate stable deviations 1
• Occlusion techniques when prisms fail:
  • Eye patching for complete monocular occlusion 2
  • Bangerter foils for partial fogging (better tolerated than surgical tape) 1
  • Scotch Satin tape as alternative to Blenderm surgical tape 1
  • Occlusive contact lenses 1

Chemodenervation with botulinum toxin during the active phase may provide temporary relief and potentially reduce residual misalignment. 1

Surgical Intervention

Timing of Surgery

Surgery should be delayed until the deviation has been stable for at least 6 months and inflammatory signs have resolved. 1 However, earlier surgery in select patients can have satisfactory outcomes and shorten disability 1

Important Pre-Surgical Considerations

If orbital decompression is indicated (for thyroid eye disease with proptosis or optic neuropathy), strabismus repair must be delayed until after decompression because alignment will change significantly. 1 Displacement of extraocular muscles into newly available space can dramatically impact ocular motility 1

Eyelid surgery should be delayed until after strabismus repair. 1

Surgical Techniques

Recession of restricted muscles is the mainstay of surgical correction for vertical diplopia. 1 Key technical points:

• Resection is generally avoided in restrictive disease due to concern for further reducing ductions, though it can be useful when extremely large recessions fail to fully correct alignment 1
• Vertical rectus transposition procedures are required for sixth nerve palsy with vertical component, including full-tendon or partial-tendon transfer with or without augmentation sutures 1
• Partial tendon transfer (loop myopexy) may decrease anterior segment ischemia risk since three extraocular muscles are not operated simultaneously 1

Expected Outcomes and Limitations

Surgery for vertical strabismus has lower success rates (66%) compared to horizontal deviations (84%) after primary surgery. 1

Patients must be counseled that the goal is eliminating diplopia in primary position and creating a reasonable field of single binocular vision—not complete resolution in all gaze positions. 1 Diplopia will likely persist in extreme lateral gaze due to difficulty balancing ductions given the underlying neurological deficit 1

Special Considerations by Etiology

Thyroid Eye Disease

Recession of the inferior rectus muscle is frequently complicated by consecutive hypertropia. 1 Strategies to minimize this complication include:

• Intentional undercorrection with adjustable sutures 1
• Wider spreading of the muscle to prevent central sagging over time 1
• Semi-adjustable suture technique (Kushner technique) to minimize unanticipated muscle drift 1
• Use of permanent sutures 1

Thyroid eye disease is the most common risk factor for "pulled-in-two syndrome"—spontaneous horizontal transection of a severely tight rectus muscle during surgery, typically 4-9mm from insertion, making recovery extremely challenging 1

Oculomotor (Third Nerve) Palsy

Vertical rectus transposition procedures are often necessary, sometimes combined with medial rectus weakening by recession or botulinum toxin injection. 1 These may be performed initially or subsequently depending on the pattern of involvement 1

Skew Deviation

Initial prism therapy may be helpful while awaiting possible recovery, with botulinum toxin, prism, or strabismus surgery considered for cases that do not resolve. 1 Surgery goals should be customized for the individual patient, addressing diplopia, head tilt, and perceived tilting of visual vertical to varying degrees 1

Binocular Central Diplopia (Dragged-Fovea Syndrome)

This condition requires special recognition because prismatic or surgical correction of measured strabismus is not curative—it does not resolve the mismatch of distorted macular images or conflict between foveal and peripheral alignment 1

Fogging one eye to eliminate foveal conflict has been most successful. 1 A small amount of prism combined with Bangerter foil can provide better relief in difficult cases 1

Surgical peeling of epiretinal membrane may be effective in some patients but may cause new diplopia in others. 1

Critical Pitfalls to Avoid

• Never perform strabismus surgery before orbital decompression in thyroid eye disease patients requiring both procedures 1
• Do not rush to surgery before 6 months of stability unless carefully selected cases 1
• Avoid resection in restrictive disease as primary approach 1
• Do not promise complete resolution—set realistic expectations about residual diplopia in extreme gaze 1
• Recognize binocular central diplopia before attempting strabismus surgery, as it will fail 1