Serviço de Cirurgia da Coluna - Hospital Lifecenter

A Feasibility Study Using Diffusion-Weighted Magnetic Resonance (DW-MR)

Neurography of the Lumbar Plexus in the Preoperative Planning of Lateral Access Lumbar Surgery

Spine Surgery Department

Hospital Lifecenter/ Ortopédico Axial Centro de Imagem

Belo Horizonte/ MG

Faculdade Medicina Ribeirão Preto USP

Brazil

Spine Midwest , St Mary’s Health Center, Jefferson City, USA

Cristiano M Menezes; Luciene M Andrade;; Carlos F. Herrero; Helton A Defino; W. Blake-Rodgers, Marcello N-Barbosa,.   

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Disclosures

• Cristiano Menezes, M.D.

•  Past and Present – Medtronic (e); Nuvasive (e)

Serviço de Cirurgia da Coluna - Hospital Lifecenter

MRI •  Fat-suppressed T2-weighted - nerve anatomy.

• A major disadvantage is the similar signal intensity of

nerves and vessels - discrimination difficult and time

consuming.

Regev. SPINE Volume 34-12, 1330–1335. 2009

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Objective

• The purpose of this study is to introduce and

assess 3DW-MR neurography for imaging of the

lumbar plexus in the pre-op planning of lateral

access surgery.

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Methods

• Ninety-four patients (188 sides) with degenerative

spinal disorders and history of low back pain

underwent a 3DW-MR examination

•  In order to evaluate their lumbar plexus anatomy and

its relation with L3L4 and L4L5 disc spaces, as well as

the superior third of the L5 vertebral body.

Serviço de Cirurgia da Coluna - Hospital Lifecenter

•  Images were reconstructed in axial plane using high-resolution 10 mm MIP* slabs over the disc space

•  and 22 mm MIP slabs in L3-L4/ L4-L5 interspace to mimic the working zone of standart lateral access retractors

•  L4 spinal nerve and FN position were analyzed relative to L45 disc – confirmed in sagittal plane (30 mm slab)

•  The area between the anterior and posterior edges of the disc space was divided into 4 zones (axial and sagittal planes)

Methods

* Maximum Intension Projection Uribe J Neurosurg Spine

13:260–266, 2010

Serviço de Cirurgia da Coluna - Hospital Lifecenter

T2 weighted axial magnetic resonance

imaging (MRI) showing L4-5

intervertebral spaces with standard

psoas muscule anatomy (A,B). MR

neurography in the same patient

demonstrating anteriorization of the

lumbar plexus to zone 2 on the right

(C,D).

Serviço de Cirurgia da Coluna - Hospital Lifecenter

•  46 female/ 48 male

•  17 to 83 years-old (mean 48,6)

•  In all subjects the plexus was succesfully mapped

•  L2/L3 and L4 roots coalesced into the FN bellow the

L4L5 disc space.

Results

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Serviço de Cirurgia da Coluna - Hospital Lifecenter

Conclusion

• DW-MR neurography appears to afford a noninvasive

method of mapping the lumbar plexus preoperatively.