A Case of Abducens Nerve Palsy after Percutaneous Nerve Block for Trigeminal Neuralgia

ABSTRACT

PURPOSE: To report a case of abducens nerve palsy after a percutaneous nerve blocking procedure for trigeminal neuralgia. CASE SUMMARY: A 35-year-old female complaining of stabbing pain in the right maxillary area 4 months in duration was diagnosed with trigeminal neuralgia at a pain clinic. The patient underwent a percutaneous trigeminal nerve blocking procedure using alcohol at the right maxillary nerve. After the procedure, the patient was referred to an ophthalmologic service for horizontal diplopia and abduction defect of her right eye. Her corrected visual acuity, intraocular pressure, pupillary response, anterior segment and fundus were normal bilaterally. The patient had right esotropia of 38 prism diopters in primary gaze (70 prism diopters in right gaze, 20 prism diopters in left gaze) with limited abduction of -3 in the right eye. She was diagnosed with abducens nerve palsy of the right eye. Three months after initial presentation, the patient had intermittent esotropia of 4 prism diopters at right gaze and orthophoria at the other diagnostic gazes; she presented no diplopia. CONCLUSIONS: In the present case study, abducens nerve palsy following a percutaneous trigeminal nerve blocking procedure resolved over 3 months. Because the abducens nerve is adjacent to the trigeminal nerve near the foramen ovale based on anatomical structure, when performing a percutaneous trigeminal blocking procedure, the surgeon should be aware that deep needle puncture could cause abducens nerve palsy.