J Neurol Surg A Cent Eur Neurosurg 2018; 79(04): 316-322
DOI: 10.1055/s-0037-1618563
Original Article
Georg Thieme Verlag KG Stuttgart · New York

Diagnosis of Lumbar Spinal Stenosis with Functional Myelography

Matthias Morgalla
1  Department of Neurosurgery, University Clinic of Tübingen, Eberhard Karls University, Tübingen, Baden-Würtemberg, Germany
,
Sandra Frantz
2  Department of Orthopedics, University of Tuebingen, Tuebingen, Germany
,
Roberto Alexandre Dezena
3  Division of Neurosurgery, Universidade Federal do Triangulo Mineiro, Uberaba, MG, Brazil
,
Carlos Umberto Pereira
4  Division of Neurosurgery, Federal University of Sergipe, Aracaju, SE, Brazil
,
Marcos Tatagiba
1  Department of Neurosurgery, University Clinic of Tübingen, Eberhard Karls University, Tübingen, Baden-Würtemberg, Germany
› Author Affiliations
Further Information

Publication History

02 January 2017

08 September 2017

Publication Date:
18 January 2018 (online)

Abstract

Background and Study Aims The diagnosis of a lumbar spinal stenosis demands advanced diagnostic radiologic techniques. In recent decades magnetic resonance imaging (MRI) has replaced myelography, now considered an old-fashioned technique. It was our hypothesis that functional myelography still plays an important role in selected cases. We investigated how our surgical strategy was influenced by the results of MRI, functional myelography, and postmyelography computed tomography (CT) in patients with a lumbar spinal stenosis.

Methods The sagittal diameters of the lumbar spinal canal were measured from L1 to S1 on patients with lumbar spinal stenosis. MRI, functional myelography, and postmyelography CT were compared in each of the patients. Sensitivity and specificity were calculated in each method. We examined how the surgical strategy was influenced by the results of these different methods.

Results Fifty consecutive patients (21 women and 29 men; mean age: 70 years, [range: 49–86 years]) fulfilled the inclusion criteria. Functional myelography revealed a sensitivity of 0.99, a specificity of 0.79, and a positive predictive value of 0.45. The MRI exhibited a sensitivity of 0.93, a specificity of 0.74, and a positive predictive value of 0.39. Postmyelography CT showed a sensitivity of 0.96, a specificity of 0.75, and a positive predictive value of 0.41. A functional myelography revealed more information than the MRI and resulted in a change in the surgical strategy in 11 of 50 patients (22%) in comparison with the sole results of MRI or a postmyelography CT.

Conclusions In selected cases with multilevel lumbar spinal stenosis, functional myelography revealed the highest precision in reaching a correct diagnosis. It resulted in a change in the surgical approach in every fifth patient in comparison with the MRI and proved most helpful, especially in elderly patients.