Posterior Ischemic Optic Neuropathy Following Radiofrequency Thermocoagulation for the Treatment of Trigeminal Neuralgia:

Bilateral Posterior Ischemic Optic Neuropathy as a Presentation of Severe Uncontrolled Diabetes Mellitus: A Case Report

INTRODUCTION

Posterior ischemic optic neuropathy (PION) is a rare, potentially devastating condition characterized by acute, painless vision loss in one or both eyes and is associated with poor outcomes. Compared with anterior ischemic optic neuropathy, little data has been published on PION, mainly in the form of case reports and anecdotal observations. This is in large part due to the low incidence of this disease.

CASE REPORT

Here, we present a newly diagnosed 45-year-old diabetic female with uncontrolled blood sugars and sudden onset bilateral sequential visual loss with left complete ophthalmoplegia with normal fundus, neuroimaging of brain, orbits, and spinal cord. She was empirically treated with intravenous steroids and insulin but her immunologic, demyelinating, and infectious etiologies workup were also normal. Ultimately, the patient was diagnosed with vision loss secondary to diabetic cranial neuropathy and PION given the rest of her evaluation was unrevealing. At discharge her visual acuity was finger counting in right eye and perception of light in left eye with an improvement in bilateral extra ocular movements. At 3 months follow-up her right eye visual acuity had improved to 6/60 while the left eye remained same with normal bilateral extra ocular movements.

CONCLUSION

Diabetic cranial neuropathy usually involves single or sequential nerve involvement but combined involvement of bilateral optic nerve and left 3, 4, and 6th cranial nerve involvement is unique to the current presentation. PION should be kept in mind in patients presenting with sudden painless bilateral vision loss with normal fundoscopy in the background of systemic disease like diabetes mellitus, though it usually occurs postoperatively.

Factors Associated With Long-Term Risk of Recurrence After Percutaneous Radiofrequency Thermocoagulation of the Gasserian Ganglion for Patients With Trigeminal Neuralgia Involving the Ophthalmic Division: A Retrospective Study

OBJECTIVE

To evaluate risk factors associated with recurrence after radiofrequency thermocoagulation (RFT) of the gasserian ganglion among patients with ophthalmic trigeminal neuralgia (TN) and prognostic factors in terms of recurrence-free survival (RFS) during a long-term follow-up.

METHODS

From January 2005 to December 2017, 300 patients with ophthalmic TN underwent RFT. A retrospective analysis of 14-year outcomes was performed. Kaplan-Meier analysis was used for RFS after the procedure. Univariate and multivariate Cox regression analyses were performed to identify risk factors for pain recurrence.

RESULTS

The initial effective rate of RFT for ophthalmic TN was 92%. The mean follow-up time was 77.38 ± 43.24 months. The cumulative probability of RFS was 86.94% at 1 year, 80.03% at 2 years, 77.27% at 3 years, 74.01% at 5 years, and 59.92% at 10 years after RFT. The mean duration of RFS was 114.67 months (95% confidence interval [CI] 106.27 to 123.06 months). In multivariate analysis, atypical pain (hazard ratio [HR] = 2.831, 95% CI 1.759 to 4.554, P < 0.001) and mild facial hypesthesia (HR = 2.540, 95% CI 1.309 to 4.931, P = 0.006) before RFT were independently associated with pain recurrence. Patients with a prognostic index (PI) > 1.27 were at high risk for pain recurrence. Major complications included troublesome dysesthesia (0.7%), keratitis (10.9%), diplopia (0.4%), facial paresthesia (6.2%), and masseter weakness (12.7%). Masseter weakness was more common in patients with V3 branch involvement. Three patients lost their sight due to keratitis.

CONCLUSION

Our study investigated long-term outcomes and complications of RFT for ophthalmic TN. Patients at high risk for pain recurrence were identified, which might provide a basis for clinical decision making before RFT.