Neurosurgery

Advanced Simulation Technologies in Brain Surgery

Table of Contents

Preoperative Simulation for Cerebrovascular Disease

Preoperative simulation is crucial for performing surgeries safely. It is no exaggeration to say that the success or failure of the surgery depends on it.

In the past, it was necessary to carefully interpret each image from CT, MRI and angiograms one by one and integrate the information in one’s mind.

However, with recent advancements in medical imaging technology, it has become possible to merge all these images. The fusion images are three-dimensional, allowing them to be viewed from various angles and enabling the capture of lesions from different perspectives.

First, we show you the actual fusion images for preoperative simulation of arteriovenous malformations (AVMs), a condition where arteries and veins are directly connected without capillaries (Fig. 1). The abnormal cluster of blood vessels can cause brain hemorrhage, seizures, and headaches, and is treated by surgical removal. Since there is a risk of massive bleeding during surgery, understanding the vascular anatomy and its relationship with surrounding brain tissue through simulation images is key to successful surgery.

Figure 1:
a: vertebral artery angiogram,
b: internal carotid artery angiogram,
c: fusion image of a and b,
d: fusion image of brain tissue and c,
e: simulation image of surgical field,
f: enlarged image of e. White arrow indicates AVM

Next are preoperative simulation images for cerebral aneurysms, which are balloon-like bulges in brain blood vessels that can lead to subarachnoid hemorrhage (Fig. 2). Utilizing a 3D printer, precise vascular models are created from imaging data for preoperative simulation.

Figure 2:
a: aneurysm before clipping,
b: aneurysm model made with a 3D printer,
c: aneurysm after clipping,
d: blood vessel model with aneurysm created using a 3D printer,
e: hollow vascular model,
f: actual patient angiogram,
g: image of the hollow vascular model. White arrow indicating the aneurysm and black dashed lines indicates the catheter

Figure2b shows the fusion 3D model of the skull and blood vessels created from data of a case planned for aneurysm clipping surgery. Holding and simulating with the model provides a much better understanding compared to just viewing images on a monitor.

Figure 2d shows another vascular model of a cerebral aneurysm, from which a hollow vascular model was created. A catheter can actually be inserted into this vascular model, making it suitable for simulating aneurysm treatment with a catheter.

Figure 2f shows the angiogram of an actual case and Figure 2g shows the image of a catheter inserted into the aneurysm of the hollow vascular model. This allows for training in an environment similar to actual surgery, improving procedural skills.

Simulation of Stereotactic Functional Brain Surgery

For involuntary movement disorders like Parkinson’s disease, dystonia, and tremor, deep brain stimulation (DBS) is performed when medication is insufficient.

This treatment involves implanting electrodes in neural nuclei such as the basal ganglia and thalamus deep within the brain, with continuous weak electrical currents adjusting abnormal neural activity.

A small hole is drilled in the skull, and electrodes about 1.3 mm in diameter are inserted while implanting a stimulator in the chest (Fig. 3a). This treatment is highly effective for many patients, but detailed preoperative functional brain imaging simulations are essential for safe and effective treatment.

Figure 3:
a: A post-DBS image reconstructed in three dimensions, showing electrodes in the skull and a stimulator in the chest.
b: A three-dimensional (3D) simulation image reconstructed from MRI images.
c: A 3D simulation image with fused angiograms identifying blood vessels to avoid bleeding risks.
d: Detailed target assessment from various directions is performed.

Recently, software using artificial intelligence (AI) technology has been developed to visualize the location of neural nuclei within the brain (Fig. 3b-d).

Stimulation adjustments are made postoperatively, requiring experience and skill, and advanced neuroimaging is also referenced.

Our hospital has extensive surgical experience with Parkinson’s disease and tremor, and is a leading facility for dystonia treatment.

Written by
Kenji Shimada, M.D.
Ryoma Morigaki, M.D.

Share this article
Table of Contents