<b><i>Background:</i></b> Focal cortical dysplasia (FCD) is one of the most important pathogenic findings in patients with extratemporal lobe epilepsy. Magnetic resonance imaging (MRI)-negative is the most important negative factor to predict postoperative seizure freedom; however, FCD-I and part of FCD-IIa are MRI-negative on routine MRI. <b><i>Objectives:</i></b> To explore the diagnostic values of 7T MRI and its new scan sequences in epilepsy patients with FCD-IIa. <b><i>Methods:</i></b> To include patients with focal seizure and suspicious focal abnormal imaging on 3T MRI during preoperative evaluation and perform a 7T MRI scan with white matter-suppressed (WMS) and gray-white matter tissue border enhancement (GWBE) sequences, resective epilepsy surgery, and postoperative pathological finding of FCD-IIa. The preoperative qualitative and localization significance of 7T MRI and 3T MRI in lesions with FCD-IIa was compared, and then, the imaging characteristics of lesions with FCD-IIa on 7T MRI were analyzed. <b><i>Results:</i></b> Ten cases were enrolled in this study. Seven tesla MRI presented high spatial resolutions and a high signal-to-noise ratio. WMS and GWBE could selectively suppress the signal of special tissue and improved the possibility of FCD findings. FCD-IIa showed abnormal thickness of gray matter and a blurring border and was hypointense on 7T MRI compared with 3T MRI. Seven patients showed improvement in the qualitative diagnosis strength grade of FCD, and 6 subjects showed improvement in the localization strength grade of the lesion border after careful reading of the 7T MR images. Significant differences were found in the qualitative diagnosis of FCD (<i>p</i> &#x3c; 0.05) and localization of the lesion border (<i>p</i> &#x3c; 0.05) between the neuroimaging diagnoses based on 3T MRI and the findings based on 7T MRI. <b><i>Conclusion:</i></b> 7T MRI with WMS and GWBE sequences shows application value in the preoperative imaging diagnosis of lesions with FCD-IIa in epilepsy patients.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and heterozygous HTRA1 mutation related cerebral small vessel disease (CSVD) are the two types of dominant hereditary CSVD. Blood-brain barrier (BBB) failure has been hypothesized in the pathophysiology of CSVD. However, it is unclear whether there are BBB damage in the two hereditary CSVD, especially in heterozygous HTRA1 mutation related CSVD. In this study, a case control design was used with two disease groups including CADASIL (n = 24), heterozygous HTRA1 mutation related CSVD (n = 9), and healthy control (n = 24) were studied. All participants underwent clinical cognitive assessments and brain MRI. Diffusion-prepared pseudo-continuous arterial spin labeling (DP-pCASL) was used to estimate water exchange rate across the BBB (kw). Correlation and multiple linear regression analysis were used to examine the association between kw and disease burden and neuropsychological performance respectively. Compared with healthy control, kw in the whole brain and multiple brain regions was decreased in both CADASIL and heterozygous HTRA1 mutation related CSVD patients (Bonferroni corrected p &lt; 0.007). In the CADASIL group, decreased kw in the whole brain (β = -0.634, p = 0.001), normal-appearing white matter (NAWM) (β = -0.599, p = 0.002), and temporal lobe (β = -0.654, p = 0.001) was significantly associated with higher CSVD score after adjusting age and sex. Reduced kw in the whole brain was significantly associated with poorer neuropsychological performance after adjusting age, sex, and education in both CADASIL and heterozygous HTRA1 mutation related CSVD group (β = 0.458, p = 0.001; β = 0.884, p = 0.008). This study showed that there was decreased water exchange rate across the BBB in both CADASIL and heterozygous HTRA1 mutation related CSVD patients, suggesting a common pathophysiological mechanism underlying the two hereditary CSVD. These results highlight the potential use of kw for monitoring the course of CADASIL and heterozygous HTRA1 mutation related CSVD, a possibility which should be tested in future research.