McCain’s Surgery May Be More Serious Than Thought, Experts Say The clot could have been in one of several locations: between the skull and the dura, the membrane that covers the brain; between the dura and surface of the brain; or inside the brain itself. A craniotomy is an opening of the skull, and an eyebrow incision would be used to reach a clot in or near the left frontal lobes of the brain, neurosurgeons who were not involved in Mr. McCain’s care said. The statement from Mr. McCain’s office said a two-inch blood clot was removed from “above his left eye” during a “minimally invasive craniotomy with an eyebrow incision” at the Mayo Clinic Hospital in Phoenix, “following a routine annual physical.” Surgeons there are not conducting interviews. That cancer history could have prompted Mr. McCain’s doctors to scan his brain even in the absence of symptoms, some doctors said. The elderly brain loses volume, and as it retracts, the bridging veins from the brain to the dura are under increasing tension, and minor trauma can cause them to ooze or leak.” The senator’s staff has not disclosed whether he takes a blood thinner. A statement released by Mr. McCain’s office on Saturday had suggested that he would be in Arizona recovering for just this week, but neurosurgeons interviewed said the typical recovery period could be longer.
