PT - JOURNAL ARTICLE AU - J G Johansen AU - S Hemminghytt AU - V M Haughton TI - CT Appearance of the retroisthmic cleft. DP - 1984 Nov 01 TA - American Journal of Neuroradiology PG - 835--836 VI - 5 IP - 6 4099 - http://www.ajnr.org/content/5/6/835.short 4100 - http://www.ajnr.org/content/5/6/835.full SO - Am. J. Neuroradiol.1984 Nov 01; 5