Contralateral Transfalcine Versus Ipsilateral Anterior Interhemispheric Approach for Midline Arteriovenous Malformations: Surgical and Anatomical Assessment

Advanced Surgical Techniques for Dural Venous Sinus Repair: A Comprehensive Literature Review

The dural venous sinus (DVS) is a thin-walled blood channel composed of dura mater that is susceptible to injury during common neurosurgical approaches. DVS injuries are highly underreported, which is reflected by a lack of literature on the topic. Neurosurgeons should be familiar with appropriate techniques to successfully repair an injured DVS and prevent associated complications. This study presents a literature review on the surgical techniques for DVS repair after DVS injury during common neurosurgical approaches. The databases PubMed and Scopus were queried using the terms "cranial sinuses," "superior sagittal sinus," "transverse sinuses," "injury," and "surgery." A total of 117 articles underwent full-text review and were analyzed for surgical approach, craniotomy, lesion location, lesion characteristics, and surgical repair techniques. A literature review was performed, and a comprehensive summary is presented. Data from publications describing DVS lacerations related to pathological conditions (eg, meningioma) were excluded. A total of 9 techniques aiding with bleeding control, hemostasis, and sinus repair and reconstruction were identified, including compression, hemostatic agents, bipolar cautery, dural tenting and tack-up suturing, dural flap, direct suturing, autologous patch, venous bypass, and ligation. The advantages and drawbacks of each technique are described. Multiple options to treat DVS injuries are available to the neurosurgeon. Treatment type is based on anatomic location, complexity of the laceration, cardiovascular status, the presence of air embolism, and the dexterity and experience of the surgeon.

Utility of a novel exoscope, ORBEYE, in gravity-assisted brain retraction surgery for midline lesions of the brain

Background

Midline brain lesions, such as falx meningioma, arteriovenous malformations, and cavernous malformations, are usually approached from the ipsilateral interhemispheric fissure. To this end, patients are positioned laterally with the ipsilateral side up. However, some studies have reported the usefulness of gravity-assisted brain retraction surgery, in which patients are placed laterally with the ipsilateral side down or up, enabling surgeons to approach the lesions through the ipsilateral side or through a contralateral interhemispheric fissure, respectively. This surgery requires less brain retraction. However, when using an operative microscope, performing this surgery requires the surgeon to operate in an awkward position. A recently developed high-definition (4K-HD) 3-D exoscope system, ORBEYE, can improve the surgeon's posture while performing gravity-assisted brain retraction surgery.

Methods

We report five cases with midline brain tumors managed by resectioning with gravity-assisted brain retraction surgery using ORBEYE. We also performed an ergonomic analysis of gravity-assisted brain retraction surgery with a craniotomy model and a neuronavigation system.

Results

Gravity-assisted brain retraction surgery to the midline brain tumors was successfully performed for all five patients, using ORBEYE, without any postoperative neurological deficit.

Conclusion

Gravity-assisted brain retraction surgery to the midline brain lesions using ORBEYE is feasible, and ORBEYE is ergonomically more favorable than a microscope. ORBEYE has the potential to generalize neurosurgical approaches considered difficult due to the surgeon's awkward position, such as gravity-assisted brain retraction surgery.

Interhemispheric Contralateral Transfalcine Approach for Subparacentral Arteriovenous Malformation: 3-Dimensional Operative Video

Neurovascular procedures along the interhemispheric fissure harbor unique features differentiating them from those arteriovenous malformations (AVMs) located at the lateral surface of the brain.1-4  The aim of this 3-dimensional operative video is to present a microsurgical resection of an AVM in a subparacentral location, operated through an interhemispheric contralateral transfalcine approach.1,3,5  This is a case of a 29-yr-old female, with headaches and history of seizures. The patient presented an interhemispheric bleeding 6 mo before the surgery. The magnetic resonance imaging (MRI) showed a vascular lesion located on the medial surface of the right hemisphere at the confluence between the cingulate sulcus and its ascending sulcus. In the cerebral angiography, a right medial AVM was observed, receiving afference from the right anterior cerebral artery and draining to the superior longitudinal sinus. The patient signed an informed consent for the procedure and agreed with the use of her images and surgical video for research and academic purposes.  The patient was in a supine position, and a left interhemispheric contralateral transfalcine approach was performed,1-3 a circumferential dissection of the nidus, and, finally, the AVM was resected in one piece.  The patient evolved without neurological deficits after the surgery. The postoperative MRI and angiography showed a complete resection of the AVM.  In the case presented, to avoid exposing the drainage vein first and to use the gravity of the exposure, the contralateral transfalcine interhemispheric approach was used,1,2 which finally accomplished the proposed objectives.

The Dural Dark-Side Approach for falcine and tentorial meningioma: A surgical series of five patients

INTRODUCTION

Falcine or tentorial meningioma can be complex to resect. When large meningiomas are located in eloquent areas, a direct ipsilateral surgical approach may cause brain injury and postoperative neurological deficits. In this series, 5 patients were surgically treated using a contralateral transfalcine or transtentorial approach to minimize brain retraction. This strategy was called the Dural Dark-Side Approach (DDSA). The aim was to analyze the quality of tumor resection and postoperative outcome.

MATERIAL AND METHODS

In our department, from June 2018 to January 2020, 5 patients underwent microsurgical DDSA for resection of 4 falcine and 1 tentorial meningioma. All tumors were selected on the following two criteria: large>40mm diameter tumor, with surrounding functional cortex. Clinical and radiologic data were retrospectively analyzed.

RESULTS AND DISCUSSION

Mean follow-up was 20 months. No patients required use of a rigid retractor during surgery. Gross total resection was performed in 3 patients and near-total resection in 2. All patients had favorable neurologic outcome. Postoperative MRI showed no ipsilateral or contralateral brain lesions.

CONCLUSION

This series suggested that meticulous DDSA allows excellent resection in selected large falcine or tentorial meningioma. The approach offered a safe and effective surgical corridor without injuring the surrounding healthy parenchyma.

Contralateral Transfalcine Approach to Deep Parasagittal Arteriovenous Malformations-Technical Note

BACKGROUND

Resection of deep medial frontal and parietal arteriovenous malformations (AVMs) is often challenging due to a tangential angle of attack and deep, narrow working corridor. Adequate visualization of the AVM and its feeding arteries without brain retraction is of particular importance when operating in or near eloquent cortical areas, where brain manipulation could inadvertently result in neurologic deficits. The aim of this paper is to provide a step-by-step description of surgical approach and report our experience with the contralateral transfalcine approach for resection of deep-seated parasagittal AVMs.

METHODS

Contralateral transfalcine resection of deep frontal, parietal, and cingulate gyrus AVMs was performed with the unaffected hemisphere positioned in a gravity-dependent manner in 5 cases. Surgical procedures were video documented, and an illustrative case is presented. All 5 patients had a modified Rankin Scale score of 0 or 1 at the last follow-up.

RESULTS

Complete resection of the AVM was achieved in all 5 cases. No permanent major neurologic deficit was observed postoperatively. This approach allowed a superior visualization of arterial feeders, the parenchymal side of the AVM, and an early control of small parenchymal feeders while minimizing retraction of the brain.

CONCLUSIONS

The contralateral transfalcine approach is a useful technique in the cerebrovascular surgeon's armamentarium for management of deep-seated medial frontal, parietal, and cingulate gyrus AVMs in or around eloquent brain areas, allowing to minimize normal brain retraction and avoid associated neurologic deficits.

Interhemispheric Surgical Approaches for Ruptured Intraventricular Arteriovenous Malformation-Associated Aneurysms: Technical Report and Case Series

BACKGROUND

Aneurysms associated with brain arteriovenous malformations (AVMs) represent a hemorrhage risk in addition to that of the AVM nidus. In high-risk or unresectable cases, targeted treatment of an aneurysm causing hemorrhage may effectively decrease future hemorrhage risk. The objective of this report is to describe our series of patients with intraventricular AVM-associated aneurysms treated surgically. We highlight technical nuances of the surgical approaches to aneurysms in the lateral and third ventricles.

METHODS

A retrospective review was performed of patients in whom an intraventricular aneurysm rupture was responsible for hemorrhage. In each patient, the aneurysm was excluded surgically via an interhemispheric approach, including transcallosal, transchoroidal, or transcingulate corridors. Aneurysm, AVM characteristics, surgical approach, and outcomes were reviewed.

RESULTS

Six patients were included in the series. In 5 patients, the disease was located on the left and approached from the right. Aneurysms were located in, or projecting into, the lateral ventricle in 4 patients (transcingulate approach) and in the third ventricle in 2 patients (transchoroidal fissure approach). The aneurysm was clipped in 1 patient and resected in 5 patients. The associated AVM was resected in 2 patients. In all patients, the surgical approach allowed adequate treatment of the aneurysm without new neurologic morbidity. No patients experienced recurrent intraventricular hemorrhage during follow-up.

CONCLUSIONS

Ruptured intraventricular aneurysms associated with brain AVMs can be treated surgically to reduce the risk of rebleeding in patients in whom the aneurysms are not accessible to endovascular treatment and in which the AVM nidus may not be safely resected.