KIBRA and APOE Gene Variants Affect Brain Functional Network Connectivity in Healthy Older People.

Genetic factors play a critical role in the development of Alzheimer's disease (AD). Kidney and brain expressed protein (KIBRA) and apolipoprotein E (APOE) are involved in episodic memory performance and AD. However, the interactions between KIBRA and APOE on brain functional network connectivity (FNC) remain unknown in healthy older people. Using independent component analysis, we systematically investigated additive and epistatic interactions of KIBRA rs1707045 and APOE on FNC in 170 healthy older Chinese people of Han ethnicity. We found significant additive KIBRA-APOE interactions on brain FNC in the right medial prefrontal cortex, the posterior cingulate cortex in the default-mode network, and the dorsal anterior cingulate cortex in the salience network. We also found significant epistatic KIBRA-APOE interactions on brain FNC in the left superior frontal gyrus and left angular gyrus in default-mode network. No significant KIBRA-APOE interactions were detected in other brain resting-state networks. These findings suggest that healthy older people have additive and epistatic interactions of KIBRA and APOE gene variants, which modulate brain FNC and may partly elucidate their association with episodic memory performance and AD.

A low-cost multimodal head-mounted display system for neuroendoscopic surgery.

Background: With rapid advances in technology, wearable devices as head-mounted display (HMD) have been adopted for various uses in medical science, ranging from simply aiding in fitness to assisting surgery. We aimed to investigate the feasibility and practicability of a low-cost multimodal HMD system in neuroendoscopic surgery. Methods: A multimodal HMD system, mainly consisted of a HMD with two built-in displays, an action camera, and a laptop computer displaying reconstructed medical images, was developed to assist neuroendoscopic surgery. With this intensively integrated system, the neurosurgeon could freely switch between endoscopic image, three-dimensional (3D) reconstructed virtual endoscopy images, and surrounding environment images. Using a leap motion controller, the neurosurgeon could adjust or rotate the 3D virtual endoscopic images at a distance to better understand the positional relation between lesions and normal tissues at will. Results: A total of 21 consecutive patients with ventricular system diseases underwent neuroendoscopic surgery with the aid of this system. All operations were accomplished successfully, and no system-related complications occurred. The HMD was comfortable to wear and easy to operate. Screen resolution of the HMD was high enough for the neurosurgeon to operate carefully. With the system, the neurosurgeon might get a better comprehension on lesions by freely switching among images of different modalities. The system had a steep learning curve, which meant a quick increment of skill with it. Compared with commercially available surgical assistant instruments, this system was relatively low-cost. Conclusions: The multimodal HMD system is feasible, practical, helpful, and relatively cost efficient in neuroendoscopic surgery.

Comparison of the Tada formula with software slicer: precise and low-cost method for volume assessment of intracerebral hematoma.

BACKGROUND AND PURPOSE: The Tada (ABC/2) formula has been used widely for volume assessment of intracerebral hematoma. However, the formula is crude for irregularly shaped hematoma. We aimed to compare the accuracy of the ABC/2 formula with open source software Slicer. METHODS: Computed tomographic images of 294 patients with spontaneous intracerebral hematoma were collected. Hematoma volumes were assessed with the ABC/2 formula and calculated with software 3D Slicer. Results of these 2 methods were compared with regard to hematoma size and shape. RESULTS: The estimated hematoma volume was 58.41±37.83 cm(3) using the ABC/2 formula, compared with 50.38±31.93 cm(3) with 3D Slicer (mean percentage deviation, 16.38±9.15%). When allocate patients into groups according to hematoma size, the mean estimation error were 3.24 cm(3) (17.72%), 5.85 cm(3) (13.72%), and 15.14 cm(3) (17.48%) for groups 1, 2, and 3, respectively. When divided by shape, estimation error was 3.33 cm(3) (9.76%), 7.19 cm(3) (18.37%), and 29.39 cm(3) (39.12%) for regular, irregular, and multilobular hematomas. CONCLUSIONS: There is significant estimation error using the ABC/2 formula to calculate hematoma volume. Compared with hematoma size, estimation error is more significantly associated with hematoma shape.