Computed tomographic scans were obtained from 19 men with long histories of heavy marijuana smoking and who were also observed to smoke large amounts of marijuana under research ward conditions. The ventricular system and subarachnoid spaces were normal in size and showed no indication of atrophic change.
(JAMA 237:1231-1232, 1977)
Kuehnle J, Mendelson JH, Davis KR, New PFJ. Computed Tomographic Examination of Heavy Marijuana Smokers. JAMA. 1977;237(12):1231-1232. doi:10.1001/jama.1977.03270390047025