Monday, November 24, 2008

Max and his head bleeds

Caution: This post gives background what we consider to be the most serious problem facing Max at the moment, and one that will likely stay with him the rest of his life. It can make for upsetting reading.

Around the time he was born, some of the blood vessels that feed into the ventricles of Max's brain ruptured. The ventricles are part of the system that produces and circulates cerebrospinal fluid (CSF). CSF bathes the brain and spine. The bleeding into Max's ventricles, and the associated clots, led to greater-than-normal pressure in the CSF system. Max's ventricles swelled and compressed some of the surrounding brain tissue. As we understand it, the part of the brain around the ventricles are mostly so-called "white matter", which transmit neural impulses to the rest of the body. The "grey matter" is associated with cognition, speech, and other higher-order thought processes.

As a result of the internal swelling, Max's head circumference grew. As an infant, his skull is designed to be subject to the extraordinary forces of birth, and so the kind of pressures that would have put an adult into a coma had no apparent effect on Max other than causing his head to grow.

Max has been treated with an aggressive course of lumbar punctures (aka LPs or taps). Each tap risks introducing bacteria to Max's menenges (the tissue surrounding the brain and spinal column). At first, the taps appeared to work: Max's head circumference fell. However, as I described in Monday's midday update, the taps are becoming harder because Max is developing fibrous tissue near his spine. Further, three or four taps a week isn't considered a long-term strategy. Finally, Max's head circumference grew again over the past few days.

The evidence, then, is that Max's head bleeds aren't resolving themselves. The next step, as described by his doctors, is, in the short term, to insert a tube through the skull into the reservoir directly. With this in place, the doctors won't need to use an LP to relieve increasing brain pressure. At some point soon, probably before he leaves the NICU, this will be replaced by a shunt, a medical appliance connecting his ventricles to (for example) his abdomen. Max will have the shunt for a long time, until medical science figures out how to control hydrocephalus medically.