Long-term results using adjunctive mitomycin C in optic nerve sheath decompression for pseudotumor cerebri.
OBJECTIVE
Up to 35% of patients undergoing optic nerve sheath decompression (ONSD) for pseudotumor cerebri who show initial improvement in visual function later show deterioration in visual field and acuity. Although repeat surgery can result in subsequent visual improvement, these procedures are technically difficult because of scarring and fibrosis. Attempting to improve the long-term success of ONSD, the authors sought to analyze the long-term success of ONSD by pretreating optic nerve sheaths with mitomycin C before incision.


METHODS
Using a standard transconjunctival medial orbitotomy, optic nerve sheaths were exposed and treated for 5 minutes with mitomycin C (0.5 mg/ml)-soaked neurosurgical cottonoids before incision.


RESULTS
Both eyes undergoing repeat ONSD with adjunctive mitomycin C had initial improvement and stable visual function for follow-up of more than 3 years. Four eyes that underwent primary ONSD all initially showed improvement in visual field. Three eyes with large cysts or fistulas remained stable. Another eye had gradual decline in visual function. Repeat ONSD in this eye showed no orbital scarring, and lysis of adhesions between dura-arachnoid and optic nerve resulted in improved, stable visual function for 31 months of follow-up.


CONCLUSIONS
Mitomycin C appears to be a safe adjunct to ONSD in a series of six patients followed between 20 and 37 months. Fistulization and cyst formation are associated with improved visual function. Closure of cysts and fistulas may result in worsening visual function due to intersheath adhesions. Repeat surgery shows significantly less orbital scarring and allows for easier and successful repeat surgery. Adjunctive mitomycin C leads to less orbital scarring after ONSD, allowing for easier repeat surgery.
Spoor
T C
TC
Kresge Eye Institute, Wayne State University, Detroit, MI 48201-1423, USA.
McHenry
J G
JG
Shin
D H
DH
D000328:Adult; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D016685:Mitomycin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D009186:Myelin Sheath; D009900:Optic Nerve / Q000187:drug effects / Q000473:pathology / Q000601:surgery*; D011559:Pseudotumor Cerebri / Q000175:diagnosis / Q000188:drug therapy / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014792:Visual Acuity
D000903:Antibiotics, Antineoplastic; D016685:Mitomycin