moyamoya_disease_classification

Moyamoya disease classification

The ischemic and hemorrhagic subtypes are difficult to diagnose prior to disease onset.

The intralateral and perilateral ventricular arteries on the original axial Time of flight magnetic resonance angiography images might suggest the hemorrhagic type of moyamoya disease prior to onset 1).

Unilateral and bilateral moyamoya disease (MMD).

Quasi Moyamoya disease

Asymptomatic Moyamoya Disease

Ischemic-type Moyamoya Disease

Suzuki and Kodoma classified the severity of moyamoya disease by progression of an occlusive process and the eventual appearance of collaterals based on serial cerebral angiographic evaluations and staged them, known as 'Suzuki stages of Moyamoya disease' which are mentioned under staging.

see Suzuki staging.


Traditional moyamoya disease (MMD) classification relies on morphological digital subtraction angiography (DSA) assessment, which do not reflect hemodynamic status, clinical symptoms, or surgical treatment outcome.

The Berlin MMD grading system is able to stratify preoperative hemispheric symptomatology. Furthermore, it correlated with postoperative new ischemic changes on MRI, and showed a strong trend in predicting clinical postoperative stroke. 2)


Ladner et al performed digital subtraction angiography and noninvasive structural and hemodynamic MRI, and they outline a new classification system for patients with moyamoya that they have named Prior Infarcts, Reactivity, and Angiography in Moyamoya Disease (PIRAMD).

Healthy control volunteers (n = 11; age 46 ± 12 years [mean ± SD]) and patients (n = 25; 42 ± 13.5 years) with angiographically confirmed moyamoya provided informed consent and underwent structural (T1-weighted, T2-weighted, FLAIR, MR angiography) and hemodynamic (T2*- and cerebral blood flow-weighted) 3-T MRI. Cerebrovascular reactivity (CVR) in the internal carotid artery territory was assessed using susceptibility-weighted MRI during a hypercapnic stimulus. Only hemispheres without prior revascularization were assessed. Each hemisphere was considered symptomatic if localizing signs were present on neurological examination and/or there was a history of transient ischemic attack with symptoms referable to that hemisphere. The PIRAMD factor weighting versus symptomatology was optimized using binary logistic regression and receiver operating characteristic curve analysis with bootstrapping. The PIRAMD finding was scored from 0 to 10. For each hemisphere, 1 point was assigned for prior infarct, 3 points for reduced CVR, 3 points for a modified Suzuki Score ≥ Grade II, and 3 points for flow impairment in ≥ 2 of 7 predefined vascular territories. Hemispheres were divided into 3 severity grades based on total PIRAMD score, as follows: Grade 1, 0-5 points; Grade 2, 6-9 points; and Grade 3, 10 points.

In 28 of 46 (60.9%) hemispheres the findings met clinical symptomatic criteria. With decreased CVR, the odds ratio of having a symptomatic hemisphere was 13 (95% CI 1.1-22.6, p = 0.002). The area under the curve for individual PIRAMD factors was 0.67-0.72, and for the PIRAMD grade it was 0.845. There were 0/8 (0%), 10/18 (55.6%), and 18/20 (90%) symptomatic PIRAMD Grade 1, 2, and 3 hemispheres, respectively.

A scoring system for total impairment is proposed that uses noninvasive MRI parameters. This scoring system correlates with symptomatology and may provide a measure of hemodynamic severity in moyamoya, which could be used for guiding management decisions and evaluating intervention response 3).


In 2014 Hung et al. proposed a quantitative method using color-coded parametric quantitative DSA (QDSA) to improve prediction of the severity of MMD. The Td significantly correlated with conventional angiographic grading and with the status of hemodynamic impairment in patients with MMD. QDSA and Td measurements can provide a simple and quantitative angiographic grading system for patients with MMD. 4).


1)
Ishikawa M, Terao S, Kagami H, Inaba M, Naritaka H. Intralateral and Perilateral Ventricular Arteries on Original Axial Magnetic Resonance Angiography in Adult Moyamoya Disease. Eur Neurol. 2021 Mar 29:1-5. doi: 10.1159/000514429. Epub ahead of print. PMID: 33780954.
2)
Teo M, Furtado S, Kaneko OF, Azad TD, Madhugiri V, Do HM, Steinberg GK. Validation and Application for the Berlin Grading System of Moyamoya Disease in Adult Patients. Neurosurgery. 2020 Feb 1;86(2):203-212. doi: 10.1093/neuros/nyz025. PMID: 30864668.
3)
Ladner TR, Donahue MJ, Arteaga DF, Faraco CC, Roach BA, Davis LT, Jordan LC, Froehler MT, Strother MK. Prior Infarcts, Reactivity, and Angiography in Moyamoya Disease (PIRAMD): a scoring system for moyamoya severity based on multimodal hemodynamic imaging. J Neurosurg. 2016 Mar 11:1-9. [Epub ahead of print] PubMed PMID: 26967789.
4)
Hung SC, Liang ML, Lin CF, Lin CJ, Guo WY, Chang FC, Wong TT, Chang CY. New grading of moyamoya disease using color-coded parametric quantitative digital subtraction angiography. J Chin Med Assoc. 2014 Aug;77(8):437-42. doi: 10.1016/j.jcma.2014.05.007. Epub 2014 Jul 12. PMID: 25028291.
  • moyamoya_disease_classification.txt
  • Last modified: 2021/03/30 09:15
  • by administrador