Is microdiffusion imaging able to improve the detection of cervical myelopathy? Study protocol of a prospective observational trial (MIDICAM-Trial)

Abstract

IntroductionThe diagnosis of degenerative cervical myelopathy (DCM) is difficult in numerous patients due to the limited correlation of clinical symptoms, electrophysiology and MRI. This applies especially for early disease stages with mild symptoms or in uncertainty due to comorbidities. Conventional MRI myelopathy signs show a restricted sensitivity to clinical symptoms of at most 60%. It is desirable to select patients for surgical treatment as early as possible before irreversible neurological damage occurs. To improve treatment, a more reliable imaging is necessary. Microdiffusion imaging (MIDI) is an innovative MRI modality to depict tissue alterations within one voxel based on diffusion-weighted imaging (DWI) postprocessing. By separating the affected area into several mesoscopic compartments, pathological changes might be detected more sensitive through this subtle tissue resolution. We hypothesise, that MIDI shows myelopathic alterations more sensitive than conventional MRI and improves the correlation to functional impairment.Methods and analysisIn this prospective, observational trial, 130 patients with a relevant degenerative cervical spinal stenosis receive MRI including MIDI and a standard clinical and electrophysiological assessment. Special subvoxel diffusion parameters are calculated. Clinical follow-ups are conducted after 3, 6 and with additional MRI and electrophysiology after 12 months. The primary endpoint is the sensitivity of MIDI to detect functional myelopathy defined by clinical and electrophysiological features correlated to conventional MRI myelopathy signs. Twenty healthy subjects will be included as negative control. The results will provide new insights into the development of mesoscopic spinal cord alterations in DCM associated to the clinical course. Aim is to improve the diagnostics of incipient myelopathy through this new modality.Ethics and disseminationThe study protocol is approved by the Ethics Committee of the University of Freiburg (reference 261/17). The results will be published in a peer-reviewed journal.Trial registration numberDRKS00012962.

Degenerative Cervical Myelopathy: Clinical Presentation, Assessment, and Natural History

“…An ongoing study is investigating the role of microdiffusion imaging (MIDI) in DCM. This modality utilizes diffusion-weighted imaging (DWI) postprocessing to detect tissue alterations in each voxel [39].…”

Automated signal intensity analysis of the spinal cord for detection of degenerative cervical myelopathy — a matched-pair MRI study

“…For the future, diagnostic accuracy and prognostic information for affected patients should be improved by combining different MRI modalities. Especially diffusion-based techniques, such as diffusion microstructural imaging (DMI) or diffusion tensor imaging (DTI), may allow conclusions about alterations of the axonal integrity and intramedullary free water distribution [ 18 , 26 , 36 – 38 ]. Cerebro-spinal fluid and spinal cord motion, assessed by phase-contrast imaging, or even specific metabolite configurations from magnetic resonance spectroscopy may provide additional pathodynamic information [ 39 – 41 ].…”

“…Healthy volunteers were recruited through a clinical announcement. Details on inclusion and exclusion criteria have been already published [ 26 ]. Both trials were approved by the institutional ethics committee (reference 261/17 and 338/17) and registered at the National Clinical Trials Registry (DRKS00012962 and DRKS00017351).…”

Quantification of cervical spinal stenosis by automated 3D MRI segmentation of spinal cord and cerebrospinal fluid space

“…This pooled data analysis was based on 114 patients affected from degenerative cervical spine disease and 88 asymptomatic volunteers that had been enrolled in two independent prospective trials, receiving an identical T2-weighted MRI sequence of the cervical spine. Included patients had to provide symptoms of degenerative cervical spine disease and radiographic disc degeneration with contact to the spinal cord or spinal stenosis with cord compression [ 7 ]. Myelopathic symptoms were not necessary for inclusion.…”

“…Myelopathic symptoms were not necessary for inclusion. Patients with contraindication for MRI, previous surgery of the cervical spine as well as non-degenerative alterations (tumor, inflammation, infection, trauma) or relevant multilevel spinal cord compression were excluded [ 7 ]. Healthy participants had to be asymptomatic without any neurological disease or severe comorbidity.…”