Verbesserte Magnetresonanz-Myelografie durch Bildfusion

Zusammenfassung

Ziel: Ziel war es zu zeigen, dass der bei der MR-Myelografie durch die starke T2-Gewichtung auftretende Nachteil der fehlenden anatomischen Zuordnung, durch eine Bildfusion sowie durch in koronarer Phasenkodierrichtung generierte Quellbilder behoben werden kann, wodurch eine dem Goldstandard – dem postmyelografischen CT – vergleichbare Bildinformation erzielt werden kann.

Material und Methoden: Untersucht wurden insgesamt 110 Patienten mit extraduralen Pathologien der HWS und der LWS. Alle Patienten erhielten eine 3D-MR-Myelografie und ein postmyelografisches CT. Anschließend wurden die MRT-Datensätze durch Bildfusion und Rekonstruktionen nachverarbeitet und mit den entsprechenden Schnittbildern des postmyelografischen CT verglichen.

Ergebnisse: Die in der Arbeit verwendete Visualisierungstechnik (3D-MR-Myelografie) ist hierbei in der Lage intradurale Substrukturen hochauflösend und artefaktfrei darzustellen. Die erreichbaren Visualisierungsergebnisse sind mit dem aktuellen Goldstandard (postmyelografisches CT) vergleichbar. Eine anatomische Zuordnung ist durch Verwendung überlagerter MRT-Sequenzen im Rahmen einer Bildfusion möglich. Die hierzu notwendigen Arbeitsschritte lassen sich rasch umsetzen und sind auf kommerziellen Workstations verfügbar.

Schlussfolgerung: Durch die Fusion von unterschiedlichen MRT-Sequenzen entstehen neue Qualitäten bei der Visualisierung komplexer 3D-Datensätze. Insbesondere können der konventionellen Myelografie einschließlich der postmyelografischen CT vergleichbare Visualisierungsergebnisse in Form der sogenannten 3D-MR-Myelografie realisiert werden. Der durch die starke T2-Gewichtung verlorene Bezug zu anatomischen Leitstrukturen kann durch Fusion mit einem weiteren MRT-Datensatz ausgeglichen werden.

Abstract

Purpose: To demonstrate that the disadvantage of missing anatomical information in heavily T2-weighted MR myelography images can be eliminated by image fusion and phase encoding in the coronal direction of the source images, resulting in MR myelography images comparable to the gold standard, i. e., post-myelography CT.

Materials and Methods: This study included 110 patients suffering from extradural pathologies of the cervical and lumbar spine. All patients were investigated using 3D MR myelography and post-myelography CT. The MRI data were post-processed using image fusion and reconstruction algorithms and were compared to the corresponding images of post-myelography CT.

Results: Our approach for visualization (3D MR myelography) was able to depict intradural structures in high spatial resolution and without artifacts. The results of our visualization approach were comparable to the gold standard – post-myelography CT. Anatomical correlation was reached by image fusion of different MR data sets. The required post-processing steps were performed quickly and were available on a commercial workstation.

Conclusion: Image fusion of different MR data sets allows for visualization of 3D data sets with enhanced quality. The results for the visualization of MR myelography in particular are comparable to conventional myelography and post-myelography CT. The missing anatomical information in heavily T2-weighted MR myelography images can be compensated by image fusion with conventional MRI.

Key words

spine - myelography - MR imagingimage fusion - post-myelography CT

• Literatur

• 1 Morishita Y, Hida S, Naito M et al. Neurogenic intermittent claudication in lumbar spinal canal stenosis: the clinical relationship between the local pressure of the intervertebral foramen and the clinical findings in lumbar spinal canal stenosis. J Spinal Disord Tech 2009; 22: 130-134
• 2 Singh K, Samartzis D, Vaccaro AR et al. Congenital lumbar spinal stenosis: a prospective, control-matched, cohort radiographic analysis. Spine J 2005; 5: 615-622
• 3 Mayhew PD, Kapatkin AS, Wortman JA et al. Association of cauda equina compression on magnetic resonance images and clinical signs in dogs with degenerative lumbosacral stenosis. J Am Anim Hosp Assoc 2002; 38: 555-562
• 4 Schafer M, Riebeling H, Hacker H. False negative myelography in surgically confirmed lumbar intervertebral disk prolapse. Neurochirurgia 1976; 19: 201-207
• 5 Hackenbroch MH, Waldecker B, Promper KH. Prolapse of the lumbar vertebral disk – correlation of CT and myelographic findings with surgical findings. Röntgenblätter 1983; 36: 50-55
• 6 Katayama H, Yamaguchi K, Kozuka T et al. Adverse reactions to ionic and nonionic contrast media. A report from the Japanese Committee on the Safety of Contrast Media. Radiology 1990; 175: 621-628
• 7 Hausegger KA, Furstner M, Hauser M et al. Clinical application of flat-panel CT in the angio suite. Fortschr Röntgenstr 2011; 183: 1116-1122
• 8 Raininko R. The value of CT after total block on myelography. Experience with 25 patients. Fortschr Röntgenstr 1983; 138: 61-65
• 9 Kampmann H, Schroedl P, Spranger M. Diagnosis of lumbar intervertebral disk prolapse by computed tomography. A comparative clinical study between myelographic, computed tomographic and the surgical research results with 158 patients. Röntgenblätter 1985; 38: 387-391
• 10 Janssen ME, Bertrand SL, Joe C et al. Lumbar herniated disk disease: comparison of MRI, myelography, and post-myelographic CT scan with surgical findings. Orthopedics 1994; 17: 121-127
• 11 Sugahara T, Korogi Y, Hirai T et al. Contrast-enhanced T1-weighted three-dimensional gradient-echo MR imaging of the whole spine for intradural tumor dissemination. Am J Neuroradiol 1998; 19: 1773-1779
• 12 Klasen J, Antoch G, Blondin D. MR imaging of the abdomen in pregnancy. Fortschr Röntgenstr 2011; 183: 514-522
• 13 Schaefer JF, Kramer U. Whole-body MRI in children and juveniles. Fortschr Röntgenstr 2011; 183: 24-36
• 14 Lemburg SP, Roggenland D, Nicolas V et al. Analysis of image acquisition, post-processing and documentation in adolescents with spine injuries – comparison before and after referral to a university hospital. Fortschr Röntgenstr 2012; 184: 810-819
• 15 Freund M, Hutzelmann A, Steffens JC et al. MR myelography in spinal canal stenosis. Fortschr Röntgenstr 1997; 167: 474-478
• 16 Kuroki H, Tajima N, Hirakawa S et al. Comparative study of MR myelography and conventional myelography in the diagnosis of lumbar spinal diseases. J Spinal Disord 1998; 11: 487-492
• 17 Eberhardt KE, Hollenbach HP, Huk WJ. 3D-MR myelography in diagnosis of lumbar spinal nerve root compression syndromes. Comparative study with conventional myelography. Aktuelle Radiol 1994; 4: 313-317
• 18 Eberhardt KE, Hollenbach HP, Tomandl B et al. Three-dimensional MR myelography of the lumbar spine: comparative case study to X-ray myelography. Eur Radiol 1997; 7: 737-742
• 19 Ferrer P, Marti-Bonmati L, Molla E et al. Value of MR myelography in the diagnosis of the spine disorders. Med Clin 2000; 115: 366-369
• 20 Bartlett RJ, Hill CA, Devlin R et al. Two-dimensional MRI at 1.5 and 0.5 T versus CT myelography in the diagnosis of cervical radiculopathy. Neuroradiology 1996; 38: 142-147
• 21 Birchall D, Connelly D, Walker L et al. Evaluation of magnetic resonance myelography in the investigation of cervical spondylotic radiculopathy. Br J Radiol 2003; 76: 525-531
• 22 Melhem ER. Technical challenges in MR imaging of the cervical spine and cord. Magn Reson Imaging Clin N Am 2000; 8: 435-452
• 23 Wang YF, Lirng JF, Fuh JL et al. Heavily T2-weighted MR myelography vs CT myelography in spontaneous intracranial hypotension. Neurology 2009; 73: 1892-1898
• 24 Bartynski WS, Lin L. Lumbar root compression in the lateral recess: MR imaging, conventional myelography, and CT myelography comparison with surgical confirmation. Am J Neuroradiol 2003; 24: 348-360
• 25 Borenstein DG, O’Mara Jr JW, Boden SD et al. The value of magnetic resonance imaging of the lumbar spine to predict low-back pain in asymptomatic subjects: a seven-year follow-up study. J Bone Joint Surg Am 2001; 83-A: 1306-1311
• 26 Fenchel M, Roser F, Nagele T et al. Syringomyelia – Syringomyelie. Fortschr Röntgenstr 2012; 184: 191-195
• 27 Maldjian C, Adam RJ, Akhtar N et al. Volume fast spin-echo imaging of the cervical spine. Acad Radiol 1999; 6: 84-88
• 28 Maldjian C, Adam RJ, Akhtar N et al. Volume (three-dimensional) fast spin-echo imaging of the lumbar spine. Acad Radiol 1999; 6: 339-342
• 29 Chiavassa H, Sans N, Galy-Fourcade D et al. HASTE sequence and cine-MRI evaluation of the cervical spinal canal: evaluation in 11 healthy subjects. J Radiol 2000; 81: 611-617
• 30 Kanno H, Ozawa H, Koizumi Y et al. Dynamic change of dural sac cross-sectional area in axial loaded magnetic resonance imaging correlates with the severity of clinical symptoms in patients with lumbar spinal canal stenosis. Spine (Phila Pa 1976) 2012; 37: 207-213
• 31 Kanno H, Endo T, Ozawa H et al. Axial loading during magnetic resonance imaging in patients with lumbar spinal canal stenosis: does it reproduce the positional change of the dural sac detected by upright myelography?. Spine (Phila Pa 1976) 2012; 37: E985-E992
• 32 Allmann KH, Schafer O, Uhl M et al. Kinematic versus static MRI study of the cervical spine in patients with rheumatoid arthritis. Fortschr Röntgenstr 1999; 170: 22-27
• 33 Muhle C, Brossmann J, Biederer J et al. Value of kinematic MRI in the evaluation of patients with exacerbated pain in cervical spine motion compared with static MRI. Fortschr Röntgenstr 2001; 173: 126-132
• 34 Schlamann M, Reischke L, Klassen D et al. Dynamic magnetic resonance imaging of the cervical spine using the NeuroSwing System. Spine (Phila Pa 1976) 2007; 32: 2398-2401