NEUROVASKULÄRE

NEUROVASCULAR

COMPRESSION

RESEARCH

The relationships between the cranial nerves and the vessels at the surface of the brainstem display a complex three dimensional (3D) formation. For a number of entities like the neurovascular compression syndromes or space occupying processes in the posterior fossa and the reqiured surgical procedures the spatial understanding of these relationships is very important. The depiction of the relationship between vessels and cranial nerves predominately was limited to a two dimensional (2D) presentation. A reproducable and comprehensible assessment was not possible untill now.

The neurovascular compression is a pathologic contact between a vessel and a cranial nerve. A series of entities are caused by such a pathologic contact. The knowledge about the neurovascular relationships is of great importance. An etiologic connection of neurovascular compression at the ventrolateral medulla to arterial hypertension is discussedand and for this the possibility of it’s demonstration is substantial.

The relevant structures are very small and a proper assignment requires great experience. 3D-visualization requires a segmentation of the tiny vascular and neural structures. A purely explicite segmentation of these small structures is extremly time consuming and results into dissatisfying results of the visualization.

In this project 3D-representations of the neurovascular relationships at the surface of the brainstem are generated based on multy modal image data by methods of image and graphic data processing. Two different strategies are embarked at the same time. On strategy is based on the improvment and automatization of morphological filtering and volume growing. This has been already well proven in a semiautomatic approach. The other strategy is based on nonlinear registration between an anatomic atlas and the anatomic volume data (MRT, CT). Different MR-sequences like the MR-CISS (Constructive Interference in Steady State) and MR-angiography (TOF: Time of Flight) or CT-angiography are the fundament of this processing. From different image data sources the best extracted information of relevant structures are registered and fused to an optimized 3D-representation.

The developed methods are used durind microvascular decompression of the neurovascular compression syndromes. For the intraoperative integration the 3D-presentations are provided to the surgeon within the sterile area. By this the surgeon is able to look at standard projections as well as to projection coresponding to the microsurgical view. Furthermore this provides an intraoperative virtual endoscopy with views of the operative anatomy and regions which are not visible by the coaxial direction of the operative microscope.

The association of neurovascular compression and arterial hypertension is being investigated in cooperative scientific study of the department of neurosurgery and the medical clinic IV - nephrology and the department of gynocolgy of the University Erlangen-Nuremberg. The neurovascular compression at the ventrolateral medulla in arterial hypertension is evaluated by the above presented modern methods of imaging and image processing. In addition the assossiation between hypertension during pregnancy and neurovascular compression is evaluated.

In a surgical study the possibility and the effectivness of microvascular decompression for the treatment of resistant arterial hypertension is under evaluation. This is the world wide first prospective clinical trial on this subject. It was possible to normalise or improve the blood pressure in a series of patients.

HOME

INTRODUCTION

CONSULTATION

NEUROVASCULAR COMPRESSION

ENTITIES

TRIGEMINAL NEURALGIA

HEMIFACIAL SPASM

GLOSSOPHARYNGEAL NEURALGIA

ARTERIAL HYPERTENSION

MICROVASCULAR DECOMPRESSION

THERMOCOAGULATION

STEREOTACTIC RADIATION