China
Africa
Explore chapters and articles related to this topic
Photoacoustic Neuroimaging
Published in Yu Chen, Babak Kateb, Neurophotonics and Brain Mapping, 2017
Lihong V. Wang, Jun Xia, Junjie Yao
Compared to planar- and circular-view PACT, a spherical-view PACT system can provide nearly isotropic spatial resolution and is ideal for volumetric imaging (Kruger et al. 2009, Xiang et al. 2013). Figure 12.5a shows a schematic of a hemispherical-view PACT system with 128 elements (Kruger et al. 2009). Each transducer element has a central frequency of 5 MHz and an active area of 3 mm in diameter. To ensure sufficient spatial sampling, the array had to rotate by 16 steps during each volumetric image acquisition, which took 1.6 s as limited by the 10 Hz laser repetition rate. The spatial resolution was measured to range from 190 to 270 μm, depending on the orientation and location of the object. Figure 12.5b is an image of a mouse brain, acquired using the hemispherical-view PACT system. Major cortical vessels, such as the confluence of sinuses (CoS), inferior cerebral vein (ICV), superior sagittal sinus (SSS), and transverse sinus (TS), can be clearly identified.
On-call top tips
Published in Sarah McWilliams, Practical Radiological Anatomy, 2011
o An MRI of the brain was performed showing the filling defect (block arrow on Fig. 10.24) in the superior sagittal sinus, extending into the right transverse sinus. This is seen by comparing the two sides. The normal left transverse sinus has a black signal void (no. 1 on Fig. 10.24) whereas the abnormal right transverse sinus has intermediatesignal intensity within (no. 2 on Fig. 10.24). Axial flair MRI shows changes in the parieto-occipital region which is bilateral ((1) on Fig. 10.24) and commonly seen in venous infarction and may be haemorrhagic.?
3D printing and virtual surgical planning in a difficult Bonebridge case
Published in Virtual and Physical Prototyping, 2019
The methods and materials to 3D print temporal bones have been published by the authors previously (Mukherjee et al. 2017) and all planning and processing was done in a research laboratory co-located within a hospital. The 3D printed temporal bone of the patient was drilled to define the boundaries of the mastoid cavity following which the FMT placement was planned (Figure 2). In this case, factors increasing the difficulty of available bone for FMT placement included a laterally placed sigmoid sinus (Figure 1), significant cholesteatoma and neosteogenesis requiring wide saucerisation of the mastoid cavity with removal of the mastoid tip (Figure 2), curvature of the skull in the retrosigmoid area with 2 large emissary veins making FMT and screw placement difficult and the surgeon’s preference not to compress the sigmoid or transverse sinus. The location of the FMT placement was chosen above the transverse sinus and only minor dural compression was seen to be required using 3 mm lifts in the preplanning.