A High-resolution Magnetic Resonance Imaging Study Aim To Make Clinical Diagnosis For Moyamoya Disease

Background and objective—Moyamoya disease(MMD) diagnosis is often uncertain. It isn’t unusual that other cerebrovascular occlusive diseases are misdiagnosed as MMD. High-resolution magnetic resonance imaging(HR-MRI)enables vessel wall assessment for more precise diagnoses. The aim of this study was to investigate the true etiologies of cerebral artery steno-occlusion in patients with a clinical diagnosis of MMD or pro-MMD(probable moyamoya disease) using HR-MRI.Methods— HR-MRI was performed on 28 patients with angiographically(digital substraction angiography DSA) proven MMD or pro-MMD. A presumptive diagnosis was made based on HR-MRI findings. Then, we compared the presumptive diagnoses made via the two different imaging technologies and analyzed significant findings.Results—Among the 14 patients with angiographically proven MMD, HR-MRI confirmed the diagnosis of MMD in 13 patients except in 1 patient who finally was considered to be intracranial atherosclerotic disease(ICAD) in bilateral cerebral hemispheres. Among the 14 patients with angiographically proven pro-MMD,HR-MRI confirmed that 5 patients was MMD, 7 patients was ICAD, one patient was arterial dissection finally, and one patient was MMD in the left cerebral hemisphere and atherosclerosis in the right side.Compared with the ICAD patients, the MMD patients had smaller vessel outer diameters in the stenotic portion of the brain(2.42±0.54 mm for MMD VS. 4.23±0.54 mm for ICAD, P < 0.01) and a lower remodeling index(57.1±12.2 for MMD VS. 100.4±4.1 for ICAD, P < 0.01).Conclusions—Many patients especially ICAD patients may be misdiagnosed as MMD in clinical practice, DSA as gold standard for diagnosing MMD clearly was not sufficiently precise for making a definitive diagnosis of MMD in certain situations.HR-MRI may assist in providing a more in-depth understanding of MMD and achieving a more reliable diagnosis.