This article describes the efforts of the US Food and Drug Administration (FDA) Office of Neurological and Physical Medicine Devices to facilitate early clinical testing of potentially beneficial neurological devices in the US. Over the past 5 years, the FDA has made significant advances to this aim by developing early feasibility study best practices and encouraging developers and innovators to initiate their clinical studies in the US. The FDA uses several regulatory approaches to help start neurological device clinical studies, such as early engagement with sponsors and developers, in-depth interaction during the FDA review phase of a regulatory submission, and provision of an FDA toolkit that reviewers can apply to the most challenging submissions.
Robert Herrmann, Maureen Dreher, Andrew Farb, Michael Hoffmann, Christopher M. Loftus, Nina Mezu-Nwaba, Vivek Pinto, Xiaolin Zheng, and Carlos Peña
Jianjian Zhang, Sirui Li, Miki Fujimura, Tsz Yeung Lau, Xiaolin Wu, Miao Hu, Hanpei Zheng, Haibo Xu, Wenyuan Zhao, Xiang Li, and Jincao Chen
Superficial temporal artery–middle cerebral artery (STA-MCA) bypass is a common approach for treating moyamoya disease (MMD); however, the selection of recipient vessels is still controversial, and its relationship with postoperative cerebral hyperperfusion (CHP) has not been revealed. The aim of the study was to investigate the relationship between the hemodynamic sources of the recipient parasylvian cortical arteries (PSCAs) and the occurrence of postoperative CHP.
The authors retrospectively analyzed the clinical data from 68 adult patients (75 hemispheres) with MMD who underwent STA-MCA bypass. Based on their hemodynamic sources from the MCA and non-MCAs, the PSCAs were classified as M-PSCAs and non–M-PSCAs, and their distributional characteristics were studied. Moreover, the patients’ demographics, incidence of postoperative CHP, and post- and preoperative relative cerebral blood flow values were examined.
The digital subtraction angiography analysis demonstrated that 40% (30/75) of the recipient PSCAs had no hemodynamic relationship with the MCA. The post- and preoperative relative cerebral blood flow values of the M-PSCA group were significantly higher than those of the non–M-PSCA group (p < 0.001). Multivariate analysis revealed that the hemodynamic source of PSCAs from the MCA was significantly associated with the development of focal (p = 0.003) and symptomatic (p = 0.021) CHP. Twelve (85.7%) of the 14 patients with symptomatic CHP and all 4 (100%) patients with postoperative hemorrhage were from the M-PSCA group.
This study revealed that direct anastomoses of PSCAs with anterograde hemodynamic sources from the MCA had a high risk of postoperative CHP during STA-MCA bypass in adult patients with MMD.