1
|
Fujita Y, Uozumi Y, Sasayama T, Kohmura E. Presence of a fundal fluid cap on preoperative magnetic resonance imaging may predict long-term facial nerve function after resection of vestibular schwannoma via the retrosigmoid approach. J Neurosurg 2022; 138:972-980. [PMID: 36152320 DOI: 10.3171/2022.8.jns221516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 08/03/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVE
Preservation of neurological function is a priority when performing a resection of a vestibular schwannoma (VS). Few studies have examined the radiographic value of a fundal fluid cap—i.e., cerebrospinal fluid in the lateral end of a VS within the internal auditory canal—for prediction of postoperative neurological function. The aim of this study was to clarify whether the presence of a fundal fluid cap on preoperative magnetic resonance images has a clinical impact on facial nerve function after resection of VSs.
METHODS
The presence of a fundal fluid cap and its prognostic impact on long-term postoperative facial nerve function were analyzed.
RESULTS
A fundal fluid cap was present in 102 of 143 patients who underwent resection of sporadic VSs via the retrosigmoid approach. Facial nerve function was acceptable (House-Brackmann grade I–II) immediately after surgery in 82 (80.4%) patients with a fundal fluid cap and in 26 (63.4%) of those without this sign. The preservation rate of facial nerve function increased in a time-dependent manner after surgery in patients with a fundal fluid cap but plateaued by 3 months postoperatively in those without a fundal fluid cap; the difference was statistically significant at 12 months (96.1% vs 82.9%, p = 0.013) and 24 months (97.1% vs 82.9%, p = 0.006) after surgery. The presence of a fundal fluid cap had a significantly positive effect on long-term facial nerve function at 24 months after surgery when tumor size and intraoperative neuromonitoring response were taken into account (OR 5.55, 95% CI 1.12–27.5, p = 0.034).
CONCLUSIONS
Neuromonitoring-guided microsurgery for total resection of VSs is more likely to be successful in terms of preservation of facial nerve function if a fundal fluid cap is present. This preoperative radiographic sign could be helpful when counseling patients and deciding the treatment strategy.
Collapse
Affiliation(s)
- Yuichi Fujita
- Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe, Hyogo; and
| | - Yoichi Uozumi
- Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe, Hyogo; and
| | - Takashi Sasayama
- Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe, Hyogo; and
| | - Eiji Kohmura
- Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe, Hyogo; and
- Department of Neurosurgery, Kinki Central Hospital, Itami, Hyogo, Japan
| |
Collapse
|