Keyhole Microsurgery for Cerebral Aneurysms

*Revaz Dzhindzhikhadze, Renat Kambiev, Andrey Polyakov, Andrey Zaitsev, Anton Ermolaev and Igor Bogdanovich*

## **Abstract**

The choice of an effective and safe surgical approach is an important and largely outcome-determining step in the microsurgical treatment of cerebral aneurysms. Transcranial approach to aneurysm should provide proximal and distal control, visualization of the aneurysm and surrounding structures, freedom to work with microinstruments, optimal and close view of the surgical field with the necessary ergonomics and the possibility of comfortable work for the neurosurgeon. In addition, the approach should provide a low risk of associated complications, good cosmetic outcomes and patient satisfaction. Today, a neurosurgeon has a sufficient number of approaches to cerebral aneurysms. Minimally invasive approaches are the reduced model of traditional approaches and each of these approaches has a specific surgical corridor that cannot be changed during microsurgical manipulations, unless through the transition to an extended craniotomy.

**Keywords:** keyhole, cerebral aneurysms, supraorbital approach, transorbital approach, microsurgery

### **1. Introduction**

The rapid development of minimally invasive neurosurgery is associated with the wide availability and distribution of highly informative neuroimaging technologies. Neurosurgeons often face the problem of choosing the most optimal treatment method in search of minimizing surgical aggression. For several decades, in the surgical treatment of aneurysms, pterional craniotomy has been the traditional approach for most aneurysms of the anterior parts of the cerebral arterial circle and the upper parts of the basilar artery [1]. However, upon critical analysis, it becomes clear that the "collateral damage" of tissues during craniotomy is not related to the immediate goal of the surgical intervention. These negative consequences affect the immediate and long-term recovery of patients and prolonged hospitalization, which leads to long-term disability and, accordingly, economic costs.

The popularization of the concept of "keyhole" surgery is associated with the possibility of accurate preoperative planning, improvement of microneurosurgical techniques, intraoperative control in the form of fluorescein angiography, video endoscopic assistance and neurophysiological monitoring, which allows focusing on the accuracy,

efficiency, and safety of surgical intervention. It is important that minimally invasive approaches make it possible to minimize iatrogenic trauma by creating an individual surgical corridor. The principle of "individual" access to cerebral aneurysms is reduced to the use of several minimally invasive approaches depending on the specific neuroimaging pattern in comparison with the previously used algorithm and the choice of pterional craniotomy for all aneurysms of the anterior cerebral arterial circle [2–7].

The modern concept of microsurgical treatment of cerebral aneurysms involves the choice of an individual approach. The main goal of individualization is to create the shortest efficient route to the target with minimal collateral damage, ensuring the safety of the intervention. Individualized minimally invasive approach in the microsurgical treatment of cerebral aneurysms improves surgical and clinical outcomes, reduces the time of surgery, length of stay in the hospital, and the cost of treatment and provides excellent cosmetic results [4, 6, 7].

The three keyhole approaches are discussed below: eyebrow supraorbital, minipterional and transorbitals.
