Tuesday, July 31, 2007

Neurological Surgery

Neonatal ICU rounds

I was able to go to NICU (neonatal ICU) rounds this past week. Unlike neurological surgery rounds, which only last about 30 minutes, the NICU rounds lasted more than 2 hours. The two were quite different not only because of the age of patients, but also it seemed that in the NICU, rounds were focused on determining the day’s treatment for the patient as well as assessing each patient’s day to day progress, whereas in neurological surgery rounds were focused on just assessing progress. The cases in the NICU were striking in demonstrating the fragility of life, and how important treatment in the beginning of life is.

Neurological Surgery

One surgical procedure I observed this week which was particularly interesting was an endoscopic resection of a colloid cyst. First, some definitions are needed – a colloid cyst is a slow-growing non-malignant tumor that is usually located in the third ventricle of the brain. The cysts are composed of a cell layer on the outside of the cyst and a creamy-like colloid in the center. The colloid cyst can block drainage of the cerebrospinal fluid (CSF) and cause hydrocephalus.

MRI image of colloid cyst in the third ventricle. http://neurosurgery.ucla.edu

The treatment options for a colloid cyst include putting in a shunt to drain the CSF or surgery to remove the cyst. Surgery can either be done by a craniotomy or through the less invasive endoscopic technique that I observed. The endoscopic resection technique involves drilling a small centimeter diameter burr hole in the skull, then putting an endoscope with a camera through the hole (see picture). The cyst location is constantly irrigated from outside to maintain a clear view. Several small instruments are guided through the tubes in the endoscope to cut and burn the tissue. Then, several holes are made in the cyst cell wall. A suction catheter is used to suck away the colloid material from the cyst. A balloon catheter is inserted inside the cyst and inflated. The catheter is removed, taking cyst wall material with it. At the end of the procedure, the doctor then uses the bipolars to burn any remaining cyst which may not have been removed. I found the suction procedure quite interesting because sometimes, the doctor would start to suck non-colloidal material into the suction tube, and then would immediately stop the suction. It seems that it would be quite easy to make mistakes with this technique if the doctor is not well-trained, which is why this procedure is only performed at select hospitals.

Image of an endoscope passing through a burr hole in the skull. http://neurosurgery.ucla.edu

Colloid cyst viewed through an endoscope. http://neurosurgery.ucla.edu

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