Incidentally detected retroperitoneal ganglioneuroma after non-vehicle traffic accident: A case report of 6 year-old boy

Ganglioneuroma is a rare benign tumor originates from neurol crest and may develop anywhere along the sympathetic nervous system is present. Nearly all patients with ganglioneuroma are older than 10 years old. In most cases ganlioneuromas are detected incidentally during work-up for unrelated conditions. Nevertheless, radiological and differential diagnosis of retroperitoneal masses may be challenging. We present management of a 6-year-old boy with ganglioneuroma that located in left retroperitoneum.

Design and computer simulation of an all-optical, long distance, soliton-based lightwave communication system using single-mode heavy metal fluoride fibers at 2.55 µm

We have studied, with computer simulation, optical solitons amplified periodically by stimulated Raman scattering process in single-mode heavy metal fluoride (HMF) fibers for a range of parameters. An optimum single-mode HMF fiber was used to design an all-optical, long distance, soliton based optical fiber communication system. The length-bandwidth product is four times that of a soliton-based optical communication system using present-day single-mode silica fibers. The single channel bandwidth-length product for a bit error rate (BER) less than 10-9 is nearly 120, 000 GHz.km. Typical amplification periods are in the range of 200-300 km; average soliton and pump power are in the range of milliwatts and hence well within the capability of semiconductor lasers. © 1990 SPIE