Optic radiation mapping reduces the risk of visual field deficits in anterior temporal lobe resection

Zhiqiang Cui; Zhipei Ling; Longsheng Pan; Huifang Song; Xiaolei Chen; Wenjian Shi; Zhiqiang Liu; Qun Wang; Zhizhong Zhang; Ye Li; Xuejie Wang; Yeqing Qing; Xin Xu; Zhiqi Mao; Bainan Xu; Xinguang Yu; Guoming Luan

Optic radiation mapping reduces the risk of visual field deficits in anterior temporal lobe resection

Int J Clin Exp Med. 2015 Aug 15;8(8):14283-95. eCollection 2015.

Authors

Zhiqiang Cui¹, Zhipei Ling¹, Longsheng Pan¹, Huifang Song², Xiaolei Chen¹, Wenjian Shi³, Zhiqiang Liu³, Qun Wang¹, Zhizhong Zhang¹, Ye Li¹, Xuejie Wang¹, Yeqing Qing⁴, Xin Xu¹, Zhiqi Mao¹, Bainan Xu¹, Xinguang Yu¹, Guoming Luan⁵

Affiliations

¹ Department of Neurosurgery, Chinese PLA General Hospital, Chinese PLA Postgraduate Medical School Beijing 100853, China.
² Department of Neurology, Hebei Province Luan County People's Hospital 063700, China.
³ Department of Neurosurgery, Affiliated Tangshan People's Hospital & Tangshan Cancer Hospital, Hebei United University Tangshan 063001, China.
⁴ Department of Radiology, Chinese PLA General Hospital, Chinese PLA Postgraduate Medical School Beijing 100853, China.
⁵ Department of Neurosurgery, Sanbo Brain Hospital, Capital Medical University, Beijing Key Laboratory of Epilepsy Beijing 100093, China.

PMID: 26550412
PMCID: PMC4613097

Abstract

Anterior temporal lobe resection (ATLR) is often complicated by superior quadrant visual field deficits (VFDs) because of damage to the anterior portion of the optic radiation (Meyer's loop). This study reports the evaluation of optic radiation mapping in protecting against VFDs in the ATLR. We retrospectively analyzed 52 patients with medically refractory temporal lobe epilepsy undergoing ATLR between January 2012 and December 2013. The surgical operations in Group I (n=32) were performed with the modified ATLR, and the operations in Group II (n=20) were aided by combining optic radiation mapping by diffusion tensor imaging, microscopic-based neuronavigation and the intraoperative magnetic resonance imaging (iMRI) technique. A t-test was used to compare the size of ATLR, and a chi square test was applied for the postoperative VFD and seizure outcomes. The optic radiation was reconstructed in all patients in Group II. The size of ATLR was 5.11±1.34 cm (3.3-8 cm), and 3.24±0.75 cm (2.2-4.8 cm) in Groups I and II, respectively; the size of ATLR was significantly smaller in Group II (F=9.803; P=0.00). The visual fields assessment by the Humphrey Field Analyser 30-2 test showed 27 patients (84.4%) in Group I suffered VFDs at 3 months post-operation, whereas only eight patients (40.0%) in Group II showed VFDs (Pearson chi square =11.01; P=0.001). The 6-month follow-up survey showed that 90.6% of patients in Group I achieved a good outcome (Engel class I-II), outperforming 85.0% in Group II, however, there was no statistically significant difference (chi square =0.382, P=0.581). This techniques of combining optic radiation mapping, microscopic-based neuronavigation and iMRI aided in precise mapping and hence reduction of the risk of visual field deficits in ATLR. The size of ATLR guided by optic radiation mapping was significantly smaller but the seizure outcome was not significantly affected.

Keywords: Intraoperative magnetic resonance imaging (iMRI); anterior temporal lobe resection (ATLR); optic radiation mapping; diffusion tensor imaging (DTI); visual field deficits (VFD).