ANATOMY OF THE GREAT VESSELS BY MAGNETIC RESONANCE IN ANTERIOR LUMBAR INTERBODY FUSION

ANATOMIA DOS GRANDES VASOS POR RESSONÂNCIA MAGNÉTICA NA FUSÃO INTERSOMÁTICA LOMBAR ANTERIOR

ANATOMÍA DE LOS GRANDES VASOS POR RESONANCIA MAGNÉTICA EN FUSIÓN INTERSOMÁTICA LUMBAR ANTERIOR

ABSTRACT

Objective:

To perform an analysis of the anatomy of the great vessels relevant to the access for anterior lumbar interbody fusion (ALIF), determining the level of their bifurcation, the distance between the iliac vessels at L5-S1, the morphological configuration of the left iliac vein and the presence of fatty tissue between the vessel and the disc.

Methods:

Two hundred magnetic resonance imaging (MRI) scans of the lumbar spine of patients (18-80 years old) were evaluated using axial, coronal, and sagittal cuts at levels L1-S1 in T2 weighting. The interiliac distance was defined as the measurement between the left iliac vein and the right iliac artery. The presence of fatty tissue was defined as the identification of space between the vessel and the disc. Vessel morphology was divided into oval and flat.

Results:

The population’s average age was 49.6 years, with 52% being female. The average interiliac distance at L5-S1 was 27.48mm. The bifurcation of the aorta artery was identified at the level of L4 in 56.3%, as well as the confluence of the iliac veins (37.2%). The left iliac vein was identified as oval in 69% of patients and flat in 31% of patients. Fat tissue was evidenced in 60.5% of the exams.

Conclusion:

As a routine preoperative examination and surgical planning, lumbar MRI is fundamental in investigating the anatomy regarding anterior approach surgeries, allowing an effective assessment of the relationships between the great vessels and the lumbar spine. Level of Evidence IV; Retrospective Investigation.

Keywords:
Spine; Magnetic Resonance; Arthrodesis; Iliac Vein