No abstract

This study was aimed at evaluating the sensitivity and safety of a new technique to record triggered EMG thresholds from axillary chest wall electrodes when inserting pedicle screws in the upper thoracic spine (T2-T6). A total of 248 (36

Transient topographical disorientation (TTD) is a short-lasting inability to find one’s way in a familiar environment, while the patient remains conscious and is able to recall what happened. We report the study of 10 patients with episodes of TTD, studied on the days following the last episode. The episodes of TTD could be separated into two types: the patients either reported difficulties in spatial orientation with preserved abilities to recognize landmarks and objects, or the difficulties appeared with the recognition of landmarks. Tests exploring spatial orientation, as well as higher visuoperceptive capacities were altered in most of the patients and brain SPECT showed hypoperfusion of the right hemisphere in all patients, which could also be demonstrated 2 years later in some cases. Altogether, our findings suggest that TTD is frequently associated with a more persistent right hemisphere dysfunction of unknown cause. This chronic alteration could represent either a sequel of the acute episode or a preexisting right hemisphere deficit, which inclined the acute insult to be manifested as TTD.

No abstract

Independent of the screw position, average t-EMG thresholds were always higher at the CV in the apex and above the apex regions, presuming that the distance from the pedicle to the spinal cord plays an important role in electrical transmission. The t-EMG technique has low sensitivity to predict screw malpositioning and cannot discriminate between medial cortex breakages and complete invasion of the spinal canal.