Pneumoencephalogram: The Proverbial Airhead
This blog was meant to discuss interventional radiography of the past and present, so I thought I might dig up a relic procedure to share with you.
When I was still teaching, I would present pneumoencephalograms to my classes each year. In 1980, however, the topic seemed more relevant than it did in 2007. In the later years, my main point was to discuss the procedure just to present the anatomy of the ventricular system.
By definition, a pneumoencephalogram is a radiographic examination of the ventricular system after the cerebrospinal fluid is replaced with contrast material. In this procedure, we use a negative contrast, air, to lower the contrast in the ventricles, thereby making them more prominent than the surrounding structures.
This procedure was developed by neurosurgeon Walter Dandy in 1919 and used extensively in the 20th Century. To those of us who have done some of these procedures-and I know there are others from the old days still out there-we remember them and offer thanks that medical science progressed and developed other procedures to obtain the same information. Thanks for the CT scanner and the MRI machines.
The actual procedure involved performing a spinal tab and replacing some of the spinal fluid with air. The patient was strapped into "that" chair. Does anyone remember "that" chair? It looked like something from an old science fiction movie.
Then, he or she was rotated around and films were taken in different positions. I explained this to my classes using the following analogy: Imagine that the patient is a partially filled soda bottle. If you rotate the bottle, you can watch the air-fluid line. What made this procedure so terrible was its aftermath; patients would endure nausea, vomiting and the worst headache imaginable. The headache would last until the spinal fluid was replenished naturally.
Thank heaven for advancing medical science.