My daughter began to experience double vision and headaches four months ago. Assuming it was an eye problem, we saw an ophthalmologist, who diagnosed her as having paralysis of a muscle that moves the eye. Since that diagnosis did not explain the headaches or the sudden onset of double vision, we requested an MRI. The MRI showed an infection in the sinus closest to the muscle. Now we have been referred to an ENT who wants a CT scan before he sees her. Is it unreasonable to request a course of antibiotic before we undertake the expense of the CT? He is quite indignant that we questioned the CT.

C.A.

The best radiologic method for examining the sinuses is a CT scan (also called CAT scan), not an MRI. This is because MRI exaggerates sinus disease -- minimal disease looks moderate, and moderate disease looks severe. It is very difficult for your ENT to assess the seriousness of your daughter's sinus disease based on an MRI. Moreover, CT provides much better anatomic detail than MRI. If your daughter were to require sinus surgery to alleviate her problems, the CT would be the surgeon's "road map." No responsible ENT would operate on the sinuses near the eye without a sinus CT.

With the facts that you have given me, I would also want to order a CT scan. The MRI findings are very suspicious, but as I noted above, the seriousness of the situation can only be properly assessed by a thorough physical examination AND a CT scan. At a minimum, your daughter's vision is in jeopardy. Nearly all doctors feel a very powerful responsibility to do what is in their patient's best interest. Your daughter's ENT is probably concerned about what may happen if this sinus infection is not appropriately diagnosed and treated.

My only criticism of this ENT is that he has requested the CT before seeing your daughter. Usually, doctors evaluate patients before ordering such tests, but I would agree that in this case a CT is almost certainly going to be necessary. However, by insisting on seeing the CT first, he has avoided having to explain the necessity of the CT to you. He may just be thinking about efficiency. If he has the CT in hand when he sees her, he will be able to discuss her diagnosis and treatment on the first visit and will not have to speculate.

A number of things in your letter are worrisome. Forgive me if I am misinterpreting your words. First, it sounds like you did not take your daughter to her pediatrician, but chose instead to take her to an ophthalmologist, assuming that she had an eye problem. If, in fact, her problems are due to sinusitis, then your assumption was incorrect. A pediatrician probably would not have made this assumption and may have been able to arrive at the correct diagnosis and provide a more rapid referral to an ENT.

Second, you state, "Since that diagnosis did not explain the headaches or the sudden onset of the double vision, we requested an MRI." Once again, you were playing doctor. Doctors live in fear of lawsuits, and if a patient (or parent) requests a study to rule out a particular problem, most doctors will oblige. Better to give in to the patient's request than to risk missing something ... even if the odds of that "something" are very small, so small that the doctor never would have ordered the study in the first place.

Finally, the fact that you would request a course of antibiotics rather than "undertaking the expense of the CT" demonstrates that you think you, not her doctor, know what is the best medical approach for your daughter. No small wonder that the ENT was "indignant."

My advice is that you stop playing doctor and start listening to your daughter's doctors. Rather than dictate her care, if you do not understand the logic of what is suggested, you should ask questions until you DO understand.