Hereditary neuropathy with liability to pressure palsies (HNPP), an autosomal dominant disorder, is characterized by recurrent isolated nerve palsies, which are precipitated by trivial compression or ...trauma. In this report, we present the clinical features, electrophysiological studies, nerve biopsy results, and molecular analyses of a Taiwanese family. Among the 7 members evaluated, one latent and three symptomatic patients were found who showed a heterogeneous presentation from asymptomatic to characteristically recurrent peripheral neuropathy. Electrophysiological studies revealed a general decrease in nerve conduction velocities in all four patients with focal conduction slowing, especially at the compression sites. A sural nerve biopsy with a teased fiber preparation in the index patient demonstrated a typical tomaculous appearance. Molecular genetic studies exhibited a deletion of the PMP22 gene in chromosome 17p11.2-12 in all 4 patients. In conclusion, the diagnosis of HNPP might be overlooked if based on clinical presentation only. Family survey and electrophysiological and genetic tests should be done to investigate this disorder.
Complications following local anesthesia for fiberoscope-assisted intubation are rare. We report a case with surgical condition indicating awake endotracheal intubation for general anesthesia, ...suffering from convulsions after receiving left superior laryngeal nerve block to facilitate the procedure. The possible cause may be accidental injection of the local anesthetic into the vertebral artery. Although the amount of local anesthetic injected was small, its concentration in the brain might be high enough to cause convulsion. The central nervous system toxicity of local anesthetic depends not only on the dosage used, but also on the rate of injection, as well as the site at which it is injected. Starting from a small dose together with careful monitoring of patient's response is advised when nerve block in the neck is performed. Here, we also emphasize the importance of availability of resuscitation equipment for maintaining adequate ventilation and circulation in case of emergency.
