The Sailor with the Zings
During Operation Desert Storm, I was working at Naval Hospital San Diego when a sailor came in complaining of jolts of pain on the side of his head. He specifically described the sensation as a "zing" coming up behind his ear and along the side of his head. He had been seen in a clinic and was told his symptoms were caused by driving a stick shift (I don’t make this stuff up). As he was not satisfied with this explanation, he requested an evaluation by a specialist.
He told me the symptoms had started a year earlier, but were gradually becoming more frequent, occurring several times a day. I performed a meticulous neurological exam which was completely normal with the exception of an absent corneal reflex in the left eye.
“First the good news,” I said. “You are going to be okay. Unfortunately I believe you have a brain tumor. It isn’t malignant because your symptoms have been present for a year and with a malignant tumor you probably would have been dead by now.”
I proceeded to order an urgent MRI. At the Navy hospital, you could order MRIs as emergency, urgent, or routine. To me, this seemed urgent. A few hours later I get paged by the radiologist wanting to know why I thought the MRI needed to be done on an urgent basis. Evidently, they triaged the requests for urgent or emergent studies.
“I think he has a brain tumor,” I said.
“Why do you thing that?” the radiologist asked.
“The patient has been having neuralgic pain for a year and has an absent corneal reflex," I replied.
“That doesn’t sound urgent if it's been going on that long. We can get it on a routine basis.”
“Whatever you say. I’m new here and don’t know how this place works. It just seemed urgent to me.”
A week and a half later, late on Friday afternoon, the radiologist pages me.
“Your patient has a huge brain tumor,” he said in a frantic tone.
“Which patient?” By this time I did not recall our earlier conversation. Who remembers what happened a week and a half ago?
“The guy you wanted the MRI on because you thought he had a brain tumor. He does.” “Oh yeah. Now I remember?”
“Well what are you going to do?”
I could tell the radiologist was getting upset. “What do you want me to do? It’s late Friday afternoon. The neurosurgeons aren’t going to operate on him over the weekend. Have him come in on Monday.”
“But. . . but,” the radiologist sputtered.
“Listen up. I told you over a week ago the guy had a tumor and you blew me off. The only difference is now we have a picture of it.”
On Monday when he returned, I went over him in detail again. The only sign was the absent corneal reflex. No ataxia, no spasticity, no long tract signs, no facial weakness, no ocular disturbance. Nothing! Anyway, it was amazing how big this tumor turned out to be. It required two procedures for the surgeons to get the whole thing out. And the sailor lived happily ever after.
The sensory exam is felt to be the least reliable part of the neurological exam. That is not necessarily so. If sensory abnormalities conform to an anatomical pattern e.g. a specific nerve, tract, or modality it can be reliable. With regard to the trigeminal nerve, checking the corneal reflex or irritating the nostril with a cotton swab is more reliable than checking touch and pin over the face. The cornea and mucus membranes of the nostril are far more sensitive than the skin. Moreover, checking the cornea (which would assess the first branch of the trigeminal nerve) is an actual reflex. Tickling the patient’s nostril (which would assess the second branch) with his eyes closed will invariably result in a reaction to being tickled (either a twitch or wrinkling the nose). This case was a good example.