Cranial nerve VI palsy after dural-arachnoid puncture.

In this article, we provide a literature review of cranial nerve (CN) VI injury after dural-arachnoid puncture. CN VI injury is rare and ranges in severity from diplopia to complete lateral rectus palsy with deviated gaze. The proposed mechanism of injury is cerebrospinal fluid leakage causing intracranial hypotension and downward displacement of the brainstem. This results in traction on CN VI leading to stretch and neural demyelination. Symptoms may present 1 day to 3 weeks after dural-arachnoid puncture and typically are associated with a postdural puncture (spinal) headache. Resolution of symptoms may take weeks to months. Use of small-gauge, noncutting spinal needles may decrease the risk of intracranial hypotension and subsequent CN VI injury. When ocular symptoms are present, early administration of an epidural blood patch may decrease morbidity or prevent progression of ocular symptoms.

Abducens nerve palsy and optic neuritis as initial manifestation in brucellosis.

Cranial nerve involvement in brucellosis is rare. We present a case of brucellosis presenting with optic neuritis and abducens nerve palsy on the left side. Cerebrospinal fluid findings indicated Brucella meningitis with high protein count, low sugar level and pleocystosis. In addition, Brucella agglutination test (Wright test) was found to be 1/128 in cerebrospinal fluid. Serum agglutination test for Brucella was also positive at 1/1280. This case was diagnosed as brucellosis involving optic and abducens nerves. The patient was treated by ceftriaxone (intravenous), rifampicin (orally) and doxycycline (orally). Two months later the patient's vision acuity in the left eye had moderately improved and the patient's left abducens palsy had almost disappeared. In conclusion, cranial nerve involvement in brucellosis can have good prognosis if anti-Brucella treatment is undertaken early.