CLINICAL CHALLENGES
Headache Hell: Part One
A patient presents with headaches and blurry vision. See what it takes to make the diagnosis.
By Eric Schmidt, O.D.

Few ocular conditions strike fear into the hearts of doctors more than a swollen optic nerve head (ONH). It's important for us to remember though, that not all swollen disks are urgently sight (or life) threatening. We need to do a systematic workup of the patient so we can make a definitive diagnosis. This case may help walk you through such a workup.

From chauffeur to patient

Angie was familiar in my practice. I saw her three to four times each year as she dutifully brought her grandmother, who was a glaucoma patient, to my office.

Angie was typically conversational and smiling, but she acted differently one particular day. She was far more quiet than usual and, though she was still smiling, had some obvious discomfort. She was also not in my office as her grandma's chauffeur today, but as a patient.

Hearing about the pains

Angie was a 30-year-old white female who, for the past three years, had suffered with head-aches. She said that at times the headaches were so severe that she'd have to stay in bed for two to three days. She didn't have a headache every day, but she explained that they'd come in spells that would last up to one week. She also said that sometimes she'd be headache-free for months.

When I asked her to describe the pain from her headaches, she said she occasionally felt pressure so bad that she worried that her eyes would pop out. Angie indicated that the headache involved both sides of her head and that most of the time, her entire head hurt. Rarely did she ever see flashes of light and specifically denied experiencing any visual aura or photopic phenomena.

Angie told me she'd been treated for migraine headaches intermittently for the past two years. A doctor had ordered a CT scan one year ago, but the results had been normal. The doctor had pre-scribed sumatriptan succinate tablets (Imitrex) p.r.n. for migraines but Angie currently wasn't taking them or any other medications. She told me that neither the sumatriptan nor any other medication helped the headache. She did say that "keeping still" was about the only thing that gave her relief.

That day in my office Angie was having a "whopper of a headache"as she said. She described this pain as a persistent pressure that had been ongoing for three days. This headache was bothering Angie even more than normal because her vision seemed blurred along with the headache.

Finding the ocular factor

Angie's visual acuity (VA) measured 20/25-2 OD, 20/25-1 OS and it didn't improve with pinhole occlusion. Her pupils were 6 mm round and reactive. I didn't find an afferent pupil defect (APD) and her extraocular muscles (EOM) showed no restrictions. Also, Angie reported no pain on movement. I refract-ed her to -0.25 -0.50 x 110 OD, -0.25 -0.75 x 180 OS, but her VA didn't improve.

Confrontation visual fields were full OU, but when I per-formed a facial grid test, Angie reported that the right side of my face appeared "kind of blurred" when she looked with her right eye. Her view was normal through her left eye. Contrast sensitivity, color vision and red cap testing were all normal as well. Angie's anterior segments were quiet and I didn't see any abnormalities with the slit lamp. Her intraocular pressure (IOP) was 19 mm Hg OD, 17 mm Hg OS. In an ocular examination, your findings should all add up and make sense. If they don't, I always listen to that nagging voice whispering in my ear to run more tests.

Heeding the nagging voice

In Angie's case, a few things troubled me. One was her VA. A person her age -- even with migraines -- should see a crisp 20/20. Also, I didn't necessarily agree with the diagnosis of migraine headaches; at least not yet. Migraines are typically one-sided headaches that usually follow more of a pattern than Angie's. And although not all migraines have visual aura or associated nausea, Angie had none of the other symptoms commonly seen with migraines. I mulled these facts over as I waited for Angie's eyes to dilate.

Pondering papilledema

My intuition proved right as I looked at her ONHs. The ONH OD was frankly swollen; I graded it as 3+ disk edema (Fig. 1). The nerve was small in size and the disk margins were completely blurred. I saw no hemorrhages or infarcts, nor did I note spontaneous venous pulse (SVP). There were no retinal hemes, edema or folds OD.

The ONH OS was also swollen, but not as much as OD (See photos on page 26). Again, the disk was small and edematous without hemorrhages or infarcts. No SVP was present and I saw no retinal pathology.

Based on the ONH appearance, it was unlikely that Angie's headaches were solely caused by a migraine syndrome. She had bilateral swollen ONH, or papilledema, which is best defined as bilateral swollen ONHs caused by increased intracranial pressure (ICP).

Angie's condition may be papilledema, but I needed to run a few more tests before confirming this diagnosis. Also, more important than merely confirming the diagnosis is to determine the cause, for this dictates the treatment. The ONH can become swollen because of inflammatory or ischemic processes.

Systemic diseases, such as meningitis or hypertension for example, as well as some ocular diseases, can yield an edematous ONH. Orbital and brain tumors or any other entity that raises ICP are also common causes of ONH edema.

Papilledema occurs when the flow of axoplasm through the optic nerve is interrupted for various reasons. The backed-up axoplasm leaks out of the nerve and accumulates at the lamina cribrosa, resulting in the classic swollen nerve head appearance.

Although some cases of papilledema present with no symptoms whatsoever, the majority have some accompanying signs or patient complaints. Generally the VA remains 20/20 in cases of true papilledema, but episodes of transient visual obscurations (TVO) are not uncommon, especially if the doctor specifically questions about them.

These TVO are precipitated by postural changes and may be severe at times. In some patients, the VA may become bad depending on the duration and the level of the elevated ICP. The visual field of most of these patients is abnormal. An enlarged blind spot is common, but an overall decrease in the mean sensitivity of the field is often seen as well. In severe or longstanding cases, visual field defects such as arcuate scotomas or hemianopias may develop. Also headaches of some degree are common in patients who have papilledema.

Making a diagnosis

In Angie's case, I was concern-ed about an intracranial mass. She wasn't sick and didn't have a fever, which made meningitis unlikely, and the appearance of her nerves weren't consistent with optic neuritis or ischemic optic neuropathy. I ordered a magnetic resonance imaging (MRI) of her head with specific instructions to rule out a mass lesion. The MRI was normal, which ruled out a brain tumor as the cause of her swollen ONH.

The next thing I did was refer Angie to a neurologist for a lumbar puncture (LP) to determine whether her ICP was actually elevated. The fluid came back clear but extremely elevated at 412 mm. The cerebrospinal fluid didn't have any evidence of virus, blood or bacteria, which ruled out meningitis. Angie did indeed have papilledema without a mass lesion. The neurologist and I agreed on a diagnosis of idio-pathic intracranial hypertension (IIH), which has historically been termed pseudotumor cerebri. We both felt that the IIH was the most likely cause of her head-ache and visual symptoms.

A happy ending?

The neurologist termed Angie "a classic pseudotumor patient" and prescribed acetazolamide 500 mg b.i.d. He also encouraged Angie to lose weight. I had a long discussion with Angie about her condition and referred her to a weight loss clinic.

I tried to reassure her that with some work on her part and regular monitoring, she should do well and that the headaches should subside -- after all, this is considered a benign disease. See how Angie makes out next month in part two.

Contributing Editor Eric Schmidt, O.D., is director of the Bladen Eye Center in Elizabethtown, N.C. E-mail him at KENZIEKATE@aol.