Current Results of the Surgical Management of Acoustic Neuroma

Abstract

A retrospective analysis of 162 consecutive cases in 160 patients who underwent microsurgical resection of vestibular schwannomas between October 1995 and June 2001 was undertaken to compare the results with those of other treatment modalities. Patient hospital records, operative video pictures, neuroimaging studies, audiograms, and follow-up data were reviewed. The mean follow-up period was 24 months.There were 34 small (<1.5 cm), 92 medium (1.5-3 cm), and 36 (>3 cm) large tumors. Six were recurrent tumors. Gross total resection was accomplished in all 34 small tumors and 92 medium tumors but only in 50% of the large tumors. Among the 126 small and medium tumors, the facial nerve was saved anatomically in 124 patients. On long-term follow up, facial function was preserved in 94.4% of all patients. Anatomically, the cochlear nerve was preserved in 55.9% of the small and 20.7% of the medium tumors. Function was preserved (Gardner-Robertson class 1 and 2) in 25% of the small and in 19.4% of the medium tumors. Cerebrospinal leakage was present in 10.5%, meningitis in 9.9%, wound infection in 3.7%, and hematoma or contusion in 2.5%. Only one patient died (mortality rate 0.6%). Our data reflect that surgical removal should be the standard management for acoustic tumors, particularly for large and medium tumors, and can be accomplished with acceptable complication rates.

Gamma Knife surgery for large vestibular schwannomas: a single-center retrospective case-matched comparison assessing the effect of lesion size

“…8,10,17,20 However, the morbidity of resection increases as a function of lesion size. 8,12,17,20 The probability of achieving a gross-total resection decreases with increasing lesion size as well, which dramatically increases the incidence of recurrence. 12,20 Because the peak incidence of VS occurs at a median of approximately 60 years and perioperative complications related to surgical intervention and general anesthesia increase dramatically with older age, many patients with VS present at an age when they are not ideal surgical candidates.…”

“…8,12,17,20 The probability of achieving a gross-total resection decreases with increasing lesion size as well, which dramatically increases the incidence of recurrence. 12,20 Because the peak incidence of VS occurs at a median of approximately 60 years and perioperative complications related to surgical intervention and general anesthesia increase dramatically with older age, many patients with VS present at an age when they are not ideal surgical candidates. 12,18,24 Given the limitations of treating these larger VSs and the evidence for SRS for small and medium-sized lesions, there have been reports of the use of radiosurgery for the treatment of large VSs with 82%-87% long-term tumor control and reasonable maintenance of neurological function.…”

“…18 However, the incidence of gross-total resection decreases dramatically with larger tumor volume, and the recurrence rates of subtotal resections range between 70% and 80% at 5 years. 1,12 The perioperative morbidity related to resection is also a significant consideration with a CSF leak rate of 8%-30%, meningitis 2%-10%, and aseptic meningitis up to 10%. 12,18 Preservation of facial nerve function ranges from 65% to 100% in various series, but there are trends toward poorer outcomes in cases with larger tumors.…”

“…1,12 The perioperative morbidity related to resection is also a significant consideration with a CSF leak rate of 8%-30%, meningitis 2%-10%, and aseptic meningitis up to 10%. 12,18 Preservation of facial nerve function ranges from 65% to 100% in various series, but there are trends toward poorer outcomes in cases with larger tumors. 12,18 Hearing preservation also ranges from 13% to 82% depending on the series, again with trends for larger tumors having lower rates.…”

“…12,18 Preservation of facial nerve function ranges from 65% to 100% in various series, but there are trends toward poorer outcomes in cases with larger tumors. 12,18 Hearing preservation also ranges from 13% to 82% depending on the series, again with trends for larger tumors having lower rates.…”