Recent research has unveiled substantial reorganization within the gray matter networks of patients diagnosed with Moyamoya disease (MMD), offering new insights on this rare cerebrovascular disorder.
Moyamoya disease is characterized by the progressive narrowing of arteries at the base of the skull, which can lead to symptoms including transient ischemic attacks and cognitive impairments. To investigate the impact of MMD on brain structure, researchers conducted a detailed analysis comparing the gray matter networks of 136 MMD patients to 99 healthy controls (HCs).
The study found significant differences between the two groups. MMD patients displayed lower clustering coefficients and local efficiency, indicative of reduced brain network connectivity. Specifically, the clustering coefficient (Cp) was significantly decreased (p = 0.006), and local efficiency (Eloc) was reduced (p = 0.013) compared to HCs.
Notably, ischemic MMD patients demonstrated even greater variations, showing decreased Eloc and increased characteristic path length (Lp) compared to asymptomatic and hemorrhagic patients (p < 0.001). These alterations signal potential deficits in the efficiency of how information is processed across the brain.
The researchers also utilized gray matter network topology analyses to observe regional abnormalities across different brain areas. They found diminished degree centrality (DC) in key regions such as the left medial orbital superior frontal gyrus and the right calcarine fissure, indicating less connectivity compared to healthy brains (p < 0.05). Conversely, increased DC was observed within the bilateral olfactory regions, underscoring unique compensatory mechanisms at play.
Interestingly, the study highlighted variations among the three types of MMD patients—ischemic, hemorrhagic, and asymptomatic—in terms of their clinical characteristics and corresponding brain network properties. Ischemic patients had reduced betweenness centrality (BC) in the right hippocampus compared to hemorrhagic patients, where differing patterns of brain connectivity were evident (p < 0.001).
These findings support the hypothesis of significant brain structure changes and suggest specific alterations of gray matter networks can be instrumental for predicting the presence of MMD-related brain lesions. The individual's brain network was constructed using fine-tuned neuroimaging techniques which provide richer, personalized insights rather than broad group averages typically employed.
The research also points to the necessity for varied approaches to treating MMD, as the differences between patients with ischemic and hemorrhagic forms show different underlying mechanisms.
This extensive analysis is instrumental not only for advancing the scientific community’s grasp of Moyamoya disease but is also pivotal for future neurological assessments and therapeutic strategies targeting cerebral blood flow issues associated with MMD.