Louisville Medicine Volume 69, Issue 5 - Page 20

50 TH ANNIVERSARY OF A MAMMOTH CONTRIBUTION TO MEDICINE
AUTHOR Vasudeva Iyer , MD
FEATURE
The very first CT scanner prototype , invented by Hounsfield .
Image used under Creative Commons license from https :// commons . wikimedia . org / wiki / File : RIMG0277 . JPG

50 TH ANNIVERSARY OF A MAMMOTH CONTRIBUTION TO MEDICINE

AUTHOR Vasudeva Iyer , MD

October 1 , 2021 , marks the day on which 50 years ago the first CT scan was performed . The year was 1971 and the occasion was when Godfrey Hounsfield ( 1919- 2004 ) used his invention , the EMI scanner at the Atkinson Morley Hospital in Wimbledon , England to scan the brain of a real patient . While the first scanners imaged only the head , by 1975 the first body scanner was installed in England and later in the US . By the end of the 1970s , the phenomenal significance of Hounsfield ’ s discovery was recognized , and in 1979 he was honored with the Nobel Prize for Physiology / Medicine . The 1980s saw significant improvements in CT technology resulting in unbelievably short scan times , larger matrix size and multi-slice technology .

1971 was a year of great importance for me personally as well ; I joined the Neurology faculty , after years of training . The generation of physicians trained after the 1980s may not be able to imagine a medical world without CT , as it has become an essential investigation
18 LOUISVILLE MEDICINE in most medical and surgical specialties . Often , medical students and residents ask me about the neurodiagnostic investigations we used in the pre-CT era . As a first-year neurology fellow , I had to spend several hours each day in the radiology suite performing studies on patients with many different varieties of brain disorders . If someone had features of dementia , the goal was to document brain atrophy by showing an increase in ventricular and subarachnoid space volume . The technique involved injection of air during a lumbar puncture ( pneumoencephalogram ); by moving the patient to sitting position , the air is made to travel up and fill the subarachnoid space and ventricles . AP and lateral radiographs facilitated quantitative measurements of the ventricular and the subarachnoid spaces . Occasionally , unexpected findings like the presence of a meningioma added to the excitement , as such lesions sometimes present with features of dementia , but without papilledema . A troublesome complication of pneumoencephalogram is severe headache , which may persist for several days . A more common diagnostic procedure was cerebral angiography for the evaluation of vascular diseases and brain tumors . Often direct common carotid artery puncture was done ; after injection of contrast agent , X-rays are taken at quick intervals to delineate the arterial , capillary and venous phases . In suspected