Figure 4

3D MR/CT fusion image showing compression of the left C7 nerve root by foraminal stenosis. Blue indicates the C6 vertebra and pink indicates the C7 vertebra. The affected roots are shown in red. Asterisks indicate ganglion. The posterolateral-inferior view of the affected root showed the flattening of the root most clearly at pre-ganglion site (Panel a), with semi-translucent C6 vertebra (Panel b). A simulated view of the operation reveals the relation between the affected C7 root and the superior articular process of C7 vertebra (Panel c) and removal of unnecessary lamina from the image reveals the pedicle and the affected root (Panel d). Panel f shows an intra-operative microscopic image from the area circled on panel e. The intra-operative pathology evident in panel f (open arrow indicates C7 root) is almost the same as that evident in the fusion image. Note that panel e shows the posterior-anterior view of the flattened root and panel b shows almost the lateral view. The surgeon must be aware of the pathoanatomical condition of a compressed root with a tortuous or twisted appearance.