How I do it: anterior interhemispheric approach to tuberculum sellae meningiomas

Acta Neurochirurgica (2021) 163:643–648

Tuberculum sellae meningiomas are deep-seated tumors difficult to access, located in close relation with important neurovascular structures. While the transsphenoidal approach is linked to specific complications, the different reported transcranial approaches are associated with advantages and drawbacks due to the respective angle of attack, with some areas adequately exposed and others partially hidden.

Method We report the technical aspects of the anterior interhemispheric approach we practice.

Conclusion This approach has the advantage of providing full control over all the vasculo-nervous structures involved and of allowing access to the medial aspect of both optic canals tangentially to the dorsum sellae.

The Contralateral Transcingulate Approach

Neurosurgery 71[ONS Suppl 1]:ons4–ons14, 2012

The contralateral transcingulate approach is a variation of the contralateral transcallosal approach for lesions located in the cingulate gyrus and deep white matter of the medial frontal lobe.

OBJECTIVE: To more thoroughly describe the contralateral transcingulate approach by reporting our operative technique and results.

METHODS: This approach positions the head with the midline horizontally, lesion on the upside, allowing gravity retraction of the dependent frontal lobe. Bifrontal craniotomy and splitting of the interhemispheric fissure create a crossing trajectory from the contralateral fissure to the ipsilateral cingulate gyrus that maximizes lateral exposure.

RESULTS: Eleven patients with vascular lesions were treated with the contralateral transcingulate approach (9 patients with cavernous malformations and 2 patients with arteriovenous malformations). Eight lesions were located on the left side, 5 in the cingulate gyrus, and 6 in the deep frontal lobe. The falx was cut in 5 patients to extend the crossing trajectory. All lesions were removed completely, with neurological morbidity in 1 patient caused by venous infarction.

CONCLUSION: Although similar to the contralateral transcallosal approach, the contralateral transcingulate approach accesses lesions outside the ventricle and has a steeper crossing trajectory. This approach requires no disruption of brain tissue with lesions on the cingulate surface and only a small incision in cingulate gyrus with lesions in the deep frontal lobe. The ipsilateral pericallosal and callosomarginal arteries provide dependable landmarks for transcingulate dissection. The contralateral transcingulate approach offers an alternative medial approach to lesions near language and motor areas and avoids lateral transcortical approaches, awake speech mapping, and risk to eloquent cortex in the dominant hemisphere.

Parafalcine and midline arteriovenous malformations: surgical strategy, techniques, and outcomes

J Neurosurg 114:984–993, 2011. DOI: 10.3171/2010.12.JNS101297

Parafalcine arteriovenous malformations (AVMs) have a midline plane in common, but differ in their location (anterior, middle, or posterior) and depth (superficial or deep). Surgical management varies with AVM location and depth in terms of patient position, head position, craniotomy, and surgical approach. This study examined surgical strategies, patient outcomes, and regional factors influencing results.

Methods. Patients with AVMs located on the medial surface of the cerebral hemisphere were identified retrospectively from a consecutive, single-neurosurgeon series that is registered prospectively as part of the UCSF Brain Arteriovenous Malformation Study Project. During a 12-year period, 443 patients with AVMs were treated surgically. Of these 443 patients, 132 (30%) had parafalcine AVMs, which were distributed in zones as follows: superficialanterior, 25 (18.9%); superficial-middle, 26 (19.7%); superficial-posterior, 39 (29.5%); deep-anterior, 25 (18.9%); deep-posterior, 17 (12.9%). Five different surgical strategies were used depending on AVM zone.

Results. Complete AVM resection was achieved in 123 (93.2%) of 132 patients. Overall, neurological condition improved in 74 patients (56.1%) and remained unchanged in 41 patients (31.1%). Neurological condition deteriorated in 12 patients (9.1%), and 5 patients (3.8%) died. Patients with AVMs in the superficial-middle zone had the highest rate of neurological deterioration (26.9%).

Conclusions. Parafalcine AVMs lie on a midline surface that, when exposed with a bilateral craniotomy across the superior sagittal sinus and a wide opening of the interhemispheric fissure, makes them superficial. However, unlike convexity AVMs, which are approached perpendicularly, parafalcine AVMs are approached tangentially. Gravity retraction is useful with deeply located AVMs (those in the deep-anterior and deep-posterior zones), because it widens the interhemispheric fissure and accesses deep arterial feeding vessels from the anterior and posterior cerebral arteries. Surgical risks were increased in the superficial-middle zone, which is likely explained by the proximity of sensorimotor cortex. The authors’ regional classification of parafalcine AVMs may serve as a guide to surgical planning.

Anterior Interhemispheric Approach for 100 Tumors in and Around the Anterior Third Ventricle

Neurosurgery 66[ONS Suppl 1]:ons65-ons74, 2010 DOI: 10.1227/01.NEU.0000365550.84124.BB

We report our experience with anterior interhemispheric approach for tumors in and around the anterior third ventricle, including surgical technique, instrumentation, pre- and postoperative hormonal disturbances, and resection rate.

METHODS: One hundred patients with 46 craniopharyngiomas, 12 hypothalamic gliomas, 12 meningiomas, 6 hypothalamic hamartomas, and 24 other lesions were operated on using an anterior interhemispheric approach with or without opening of the lamina terminalis. This surgical approach involves no frontal sinus opening; a narrow (approximately 15–20 mm in width) access between the bridging veins, which is sufficient to remove the tumor totally; and sparing of the anterior communicating artery. Specially designed long bipolar forceps and scissors are necessary for this approach, and concomitant use of angled instruments (endoscope, aspirator, and microforceps) is required frequently. The postsurgical follow-up period varied from 4 months to 18 years. RESULTS: Total removal of the neoplasm was accomplished in 37 of 46 patients with craniopharyngiomas (80.4%), whereas subtotal resection was performed in hypothalamic gliomas. No significant differences in pre- and postoperative hormonal disturbances were observed in 37 craniopharyngiomas and 10 hypothalamic gliomas. There was no operative mortality. Visual acuity was preserved or improved in 68 of 75 patients assessed. The Karnofsky Performance Scale score did not deteriorate in 72 of 75 patients tested.

CONCLUSION: The minimally invasive anterior interhemispheric approach, with or without opening of the lamina terminalis, is useful for removal of tumors in and around the anterior third ventricle, such as craniopharyngiomas and hypothalamic gliomas.