Assessment of resting cerebral perfusion between methamphetamine-associated psychosis and schizophrenia through arterial spin labeling MRI.

OBJECTIVE: The clinical manifestations of methamphetamine (METH)-associated psychosis (MAP) and acute paranoid schizophrenia (SCZ) are similar. This study aims to assess regional cerebral blood flow (rCBF) in individuals who use METH and in those with SCZ using the MRI arterial spin labeling (ASL) technique. METHODS: We prospectively recruited 68 participants and divided them into four groups: MAP (N = 15), SCZ (N = 13), METH users with no psychosis (MNP; N = 22), and normal healthy controls (CRL; N = 18). We measured rCBF using an MRI three-dimensional pseudo-continuous ASL sequence. Clinical variables were assessed using the Positive and Negative Syndrome Scale (PANSS) and Brief Assessment of Cognition in Schizophrenia (BACS). Group-level rCBF differences were analyzed using a two-sample t-test. RESULTS: Decreased rCBF was found in the precuneus, premotor cortex, caudate nucleus, dorsolateral prefrontal cortex, and thalamus in the MNP group compared with the CRL group. The MAP group had significantly decreased rCBF in the precuneus, hippocampus, anterior insula, inferior temporal gyrus, inferior orbitofrontal gyrus, and superior occipital gyrus compared with the MNP group. Increased rCBF in the precuneus and premotor cortex was seen in the MAP group compared with the SCZ group. rCBF in the precuneus and premotor cortex significantly correlated negatively with the PANSS but correlated positively with BACS scores in the MAP and SCZ groups. CONCLUSION: METH exposure was associated with decreased rCBF in the precuneus and premotor cortex. Patients with MAP exhibited higher rCBF than those with SCZ, implying preserved insight and favorable outcomes. rCBF can therefore potentially serve as a diagnostic approach to differentiate patients with MAP from those with SCZ.

Intensity of arterial structure acquired by Silent MRA estimates cerebral blood flow.

BACKGROUND: Cerebral blood flow (CBF) and the morphology of the cerebral arteries are important for characterizing cerebrovascular disease. Silent magnetic resonance angiography (Silent MRA) is a MRA technique focusing on arterial structural delineation. This study was conducted to investigate the correlation between Silent MRA and CBF quantification, which has not yet been reported. METHODS: Both the Silent MRA and time-of-flight magnetic resonance angiography scans were applied in seventeen healthy participants to acquire the arterial structure and to find arterial intensities. Phase-contrast MRA (PC-MRA) was then used to perform the quantitative CBF measurement of 13 cerebral arteries. Due to different dataset baseline signal level of Silent MRA, the signal intensities of the selected 13 cerebral arteries were normalized to the selected ROIs of bilateral internal carotid arteries. The normalized signal intensities were used to determine the relationship between Silent MRA and CBF. RESULTS: The image intensity distribution of arterial regions generated by Silent MRA showed similar laminar shape as the phase distribution by PC-MRA (correlation coefficient > 0.62). Moreover, in both the results of individual and group-leveled analysis, the intensity value of arterial regions by Silent MRA showed positively correlation with the CBF by PC-MRA. The coefficient of determination (R2) of individual trends ranged from 0.242 to 0.956, and the R2 of group-leveled result was 0.550. CONCLUSIONS: This study demonstrates that Silent MRA provides valuable CBF information despite arterial structure, rendering it a potential tool for screening for cerebrovascular disease.

Predictive imaging for tumor response to drug-eluting microsphere transarterial chemoembolization in patients with BCLC-C advanced hepatocellular carcinoma.

Drug-eluting microsphere transarterial chemoembolization (DEM-TACE) has been introduced to ensure more sustained and tumor-selective drug delivery for permanent embolization of HCC. The aim of this study was to determine the imaging characteristics that related to favourable treatment response in BCLC-C HCC patients treated with DEM-TACE. In total, 64 patients with BCLC-C HCC that treated with DEM-TACE using doxorubicin-eluted microspheres were retrospectively included. The images were assessed at baseline and at 4-12 weeks follow-up after receiving DEM-TACE. Pre- and post-procedural imaging characteristics were analysed by two independent radiologists and treatment response was evaluated using the modified Response Evaluation Criteria in Solid Tumors criteria. Multivariate analysis showed that vascular lake phenomenon (OR = 5.94, p = 0.03*), and homogeneous tumor enhancement (HTE) on cone-beam computed tomography (CBCT) during angiography (OR = 11.66, p < 0.001*) are associated with better radiological response. In contrast, residual tumor blush (OR = 0.11, p < 0.001*) is associated with worse radiological response. In conclusion, the initial tumor burden <50% (p = 0.012*) and HTE on CBCT (p = 0.040*) are good predictors for locoregional tumor control in patients with advanced HCCs, which can potentially improve patients' outcome.

Imaging Features of Soft-Tissue Calcifications and Related Diseases: A Systematic Approach.

Soft-tissue calcification refers to a broad category of lesions. Calcifications are frequently identified by radiologists in daily practice. Using a simple algorithm based on the distribution pattern of the lesions and detailed clinical information, these calcified lesions can be systematically evaluated. The distribution pattern of the calcific deposits enables initial division into calcinosis circumscripta and calcinosis universalis. Using laboratory test results (serum calcium and phosphate levels) and clinical history, calcinosis circumscripta can be further categorized into four subtypes: dystrophic, iatrogenic, metastatic, and idiopathic calcification. This pictorial essay presents a systematic approach to the imaging features of soft-tissue calcifications and related diseases.