Clinical Scorecard: Surgical Approach to Optic Nerve Decompression in a Pediatric Case of Osteopetrosis

At a Glance

Key Highlights

• Optic nerve decompression achieved via staged pterional craniotomy with anterior clinoidectomy and optic canal unroofing.
• Intraoperative challenges include hypertrophic bone and difficulty in extradural optic nerve identification, necessitating intradural durotomy.
• Postoperative visual function remained stable, confirming safety and effectiveness of the surgical approach.

Guideline-Based Recommendations

Diagnosis

• Preoperative assessment includes visual acuity, fundoscopy, visual evoked potentials, and optical coherence tomography.
• Visual field testing may be limited by patient cooperation in pediatric cases.

Management

• Perform staged optic nerve decompression starting with the more affected eye to preserve contralateral vision if complications arise.
• Use neuronavigation and microsurgical techniques for precise anatomical identification and safe bone removal.
• Continuous irrigation during drilling to prevent thermal injury and application of papaverine to improve optic nerve perfusion.

Monitoring & Follow-up

• Postoperative monitoring of visual acuity and retinal nerve fiber layer thickness via optical coherence tomography.
• Clinical observation for stability or improvement of visual function.

Risks

• Potential worsening of vision postoperatively necessitates staged approach.
• Challenges due to hypertrophic bone increasing risk of incomplete decompression or injury.
• Thermal injury during drilling if irrigation is inadequate.

Patient & Prescribing Data

Five-year-old girl with genetically confirmed osteopetrosis type II and bilateral vision worsening

Staged surgical decompression with six-week interval between eyes resulted in stable postoperative vision and effective optic nerve decompression.

Clinical Best Practices

• Position patient supine with head elevated and rotated 45° contralaterally secured in Mayfield clamp for optimal surgical access.
• Use a skin incision anterior to the tragus extending behind hairline for pterional craniotomy.
• Transect meningo-orbital band and decompress superior orbital fissure to access anterior clinoid process.
• Perform vertical durotomy parallel to Sylvian fissure to facilitate early intradural optic nerve identification.
• Drill optic canal roof and optic strut with fine diamond drill under continuous irrigation to avoid thermal injury.
• Transect falciform ligament and remove hypertrophic bone to achieve 180° optic nerve decompression.
• Apply papaverine solution intraoperatively to enhance optic nerve perfusion.

References

• Surgical decompression techniques and timing in osteopetrosis-related optic neuropathy
• Importance of early intervention in autosomal dominant osteopetrosis to prevent vision loss