✓ Difficulty swallowing due to damage of the vagus nerve is one of the most devastating complications of surgery in and around the medulla oblongata; therefore, intraoperative anatomical and functional evaluation of this nerve is crucial. The authors applied endotracheal tube surface electrodes to record electromyography (EMG) activity from vocal cords innervated by the vagus nerve. The vagal nucleus or rootlet was electrically stimulated during surgery and vocalis muscle EMG activities were displayed by auditory and visual signals. This technique was used successfully to identify the vagus motor nerve and evaluate its integrity during surgery. The advantages of this method compared with the use of needle electrodes include safe simple electrode placement and stable recording during surgery. In cases involving a pontine cavernoma pressing the nucleus or a jugular foramen tumor encircling the rootlet, this method would be particularly valuable. Additional studies with a larger number of patients are needed to estimate the significance of this method as a means of functional monitoring to predict clinical function.
Nobuhiro Mikuni, Takeshi Satow, Junya Taki, Namiko Nishida, Rei Enatsu and Nobuo Hashimoto
Takeshi Satow, Shigeki Yamada, Miyuki Yagi and Masaaki Saiki
The authors report a case of superficial siderosis of the CNS that developed after ventriculoperitoneal (VP) shunt placement for normal-pressure hydrocephalus.
A 65-year-old woman had undergone VP shunt insertion for normal-pressure hydrocephalus. Her gait disturbance, memory disturbance, and urinary incontinence all improved after the procedure. Two years later, however, her gait became ataxic and her appetite became poor. Brain MR imaging revealed a rim of hypointensity on T2-weighted sequences, enveloping the surface of the cortical fissure, cerebellum, and brainstem. Superficial siderosis of the CNS was diagnosed. Steroid administration improved her symptoms.
The authors know of only one case of superficial siderosis developing after VP shunt surgery in the English-language literature. Superficial siderosis should be acknowledged as a possible complication of VP shunt.
Yuya Matsui, Yohei Mineharu, Takeshi Satow, Noriyoshi Takebe, Eiji Takeuchi and Masaaki Saiki
Cobb syndrome is a rare, noninherited, neurocutaneous disease characterized by vascular abnormality of the spinal cord and is associated with vascular lesions in the skin at the same metamere. The majority of spinal vascular lesions are arteriovenous malformations, and skin lesions are mostly port-wine angiomas. The authors report the first case of multiple intramedullary cavernous angiomas (CAs) accompanied by skin CAs within the same metamere. A 42-year-old man presented with an acute onset of gait disturbance, low-back pain, and urinary incontinence. Magnetic resonance imaging of the thoracolumbar spine showed homogeneously enhanced lesions on a contrast-enhanced T1-weighted image and a hypointense area on a T2*-weighted image surrounding this enhanced lesion, between the T-12 and S-1 levels. Purple protruding skin lesions were detected on the left side of his gluteal region. The patient received a laminectomy followed by evacuation of a hematoma and partial removal of the tumor, which completely resolved his neurological symptoms. Pathological examinations showed that the spinal and skin lesions were CAs, suggesting that these vascular lesions developed congenitally. Cavernous angiomas associated with Cobb syndrome present with multiple lesions spanning more than 3 vertebral levels, making it difficult to completely resect these tumors. Although Cobb syndrome is an uncommon disease entity, it should be considered if a patient manifesting with neurological deficits has skin vascular lesions, including CAs.