Diagnosis And Microsurgical Management Of Trigeminl Neuriomas

Objective To investigate the diagnosis and the microsurgical management of trigeminal neurinomas.Methods Between January 2003 and December 2010, 41 patients with trigeminal neurinomas were managed with different microsurgical methods in the neurosurgery department in the First Affiliated Hospital of GuangXi Medical University, whose clinical manifestations, preoperative CT and MRI features, operative techniques and outcome were retrospectively analyzed. In the meantime, the relating reports of trigeminal neurinomas in the current literature were reviewed.Results The most frequent symptoms and signs were numbness and/or paraesthesia in one or more of the three trigeminal branches of the ipsilateral, which was frequently accompanied with the damage of oculomotor nerve, trochlear nerve , abducens nerve, facial nerve and vestibulocochlear nerve .The head CT and MRI were the major means for diagnosis of the lesions. There were 3 Type M tumors , 8 Type P tumors, 8 Type Mp tumors , 12 Type M=P tumors, 6 Type Pm tumors, 2 Type ME tumors and 2 Type MPE tumors. 13 patients were managed with Frontotemporal Epidural Approach with or without zygomatic osteotomy,14 patients with Subtemporal Transtentoria Aproach, 3 patients with Presigmoid Approach, 11 patients with Retrosigmoid Approach. Total resection was achieved in 35 patients , subtotal resection in 5 patients and partial resection in 1 patient. Bacterial meningitis, cerebrospinal fluid leakages and intracranial hematoma occurred in 2 cases respectively, pulmonary infections in 1 case. 13 patients with new incomplete paralysis of cranial nerve and 4 patients with cranial nerves deficits worsened after operation included oculomotor nerves, trochlear nerve, trigeminal nervs, abducens nerves, facial nerves and glossopharyngeal and vagus nerves . The rest damaged nerves were improved postoperatively. The symptoms and signs included exophthalmos, cerebellar ataxia, hypertensive intracranial syndrome, facial pain, hemiparesis obviously alleviated. 13 patients were followed up for 3 months to 7 years , tumor recurrence was found in 2 cases .Conclusion There are characteristic clinical manifestations in the patients with trigeminal neurinomas, whose most frequent symptoms are numbness and/or paraesthesia in one or more of the three trigeminal branches of the ipsilateral, which is frequently accompanied with the damage of the adjacent nerves and/or the adjacent brain tissue. A proper diagnosis is based on the characteristic clinical manifestations and the head imaging features. It is indispensable to distinguish from meningeoma, acoustic neurinoma and cholesteatoma. The basis of choosing individual surgical approach is the tumor type and the adjacent tissue. It is optimal to remove the mainly Type M tumor(include Type M tumor, Type Mp tumor, Type ME tumor) via Frontotemporal Epidural Approach with or without zygomatic osteotomy , the Type M=P tumor via Subtemporal Transtentoria Aproach, the Type Pm tumor via Presigmoid Approach or Retrosigmoid Approach, the Type P tumor via Retrosigmoid Approach. It can provide better exposure of these tumors and improve the surgical results in terms of increased complete tumor resection rate and reduced complications rate.