Computer assisted brain surgery for small lesions in the central sensorimotor region

Abstract

The capacity of a new optical navigation device is demonstrated by six microsurgical procedures for small subcortical lesions within the central sensorimotor strip. This small series is aimed at less invasive resection in this functionally critical region, independently of primary diagnosis and outcome. Guided by high resolution CT imaging data five brain tumours and one cavernous angioma was selectively located and most sparingly removed without additional sensorimotor deficit. In two cases improvement of a pre-operative paresis was observed immediately after surgery. Thanks to light-weight freehand pointing instruments and a ranging accuracy of +/- 1 mm, damage to functionally important brain areas and vessels was avoided by using uncommonly oblique, e.g., transsulcal ways of access which would hardly have been possible even with guidance by conventional stereotaxy. The demanding systematic cortical stimulation of the precentral gyrus applied in three cases was only sensitive in infiltrating tumours-e.g., low grade astrocytomas-where for want of adjuvant therapy it was essential to proceed to the extreme limits of resection. In general, precise anatomical localisation by computer aided surgery (CAS) is sufficient in small central lesions which guarantees minimally invasive surgery. The potential of this new, soon commercially available optical navigation system in (neuro) surgery, quality control and teaching is discussed.

The Computer-Assisted Localizer, a Navigational Help in Microneurosurgery

“…A reliable localization of all lesions at the beginning of surgical procedures was possible, and this is conform with results in the recent literature [6,8,[11][12][13][14]. Initial ex pectations and the desired aim to control the degree of tumor resection by CAL were not fulfilled, because continuous debulking of the lesion and the consecutive extension of the surrounding and compressed brain tissue per manently alter anatomical situations [2], Therefore, the progressive decrease in accura cy is inevitable, because CAL works with inappropriate and not actualized data which are based on preoperative neuroradiological images [3].…”

Cerebral cavernomas in the adult. Review of the literature and analysis of 72 surgically treated patients

“…According to the assessment of different authors, neuronavigation is particularly useful for craniotomy planning in superficial lesions and for localization of small, deep-seated cavernous malformations [157,200,264,287]. It is valuable to create and plan the surgical vectors prior to surgery, thus influencing the extent of the surgical approach (Fig.…”

Frameless Neuronavigation Using the ISG-System in Practice: From Craniotomy to Delineation of Lesion

“…Three different methods have evolved. These include combination with microscopes [18,21,27,29], systems with a fixed mechanical arm [6,7,14,15,28] and those with a hand-held pointer system [1,2,19,20,22,24,26].…”