Orbital inflammation a response, not a diagnosis

London-Orbital inflammation occurs as the result of an underlying disease process and is not itself a diagnosis. Geoffrey E. Rose, MBBS, instructed ophthalmologists on how best to approach these cases and arrive at a meaningful diagnosis and appropriate course of treatment.

"The most important point is that orbital inflammation is a tissue response and not a diagnosis. Whenever a pathology report lists 'inflammation,' this is not the diagnosis, but rather only the process," he emphasized.

In the presence of orbital inflammation, there can be infective pathogens (bacterial, fungal, or yeast, and parasitic agents) and noninfective processes (chemical and neoplastic, vasculitic, and ischemic inflammation).

Underlying pathology

Dr. Rose described numerous cases of inflammation that was the result of many different underlying pathologies. In the case of one patient who presented with clinically obvious inflammation, nonsteroidal anti-inflammatory drugs were prescribed for a marked inflammatory response, but the actual diagnosis was a leaking deep orbital dermoid.

Another example involved two patients who presented with orbital inflammation that was treated with systemic steroids prior to referral: One patient's ultimate diagnosis was systemic lymphoma involving the orbit, and the other had myeloid leukemia. In both cases there had been a clinical response to administration of systemic steroids, but the steroids had failed to address the actual pathology.

Another patient presented with inflammation and pain of 3 weeks' duration; the ultimate diagnosis was rhabdomyosarcoma. Likewise, a patient presenting with orbital cellulitis had received a previous diagnosis of sinusitis and undergone exploratory sinus surgery before referral; he actually had necrotic adenocarcinoma in the inferior rectus muscle.

The message in all these cases, Dr. Rose emphasized, is that the inflammation was secondary to another underlying process and ophthalmologists should be alert to this.

Idiopathic inflammation

He discussed patients with true idiopathic inflammatory disease, in which another cause cannot be determined.

"I have banned the use of the term 'pseudotumor' in the hospital, because the term is a dangerous anachronism. It is not a diagnosis. I advise that clinicians use 'idiopathic inflammation' where the cause is unknown, and that they remain open-minded to the possible later discovery of an underlying cause," he stated.

In four patients who were given a diagnosis of "pseudotumor" prior to referral, one had been treated with steroids for 15 months and ultimately developed no light perception vision. She was later found to have a tuberculoma within the orbit.

"If she had had a biopsy, she would have received appropriate treatment and not lost her vision," Dr. Rose said.

Of the remaining three patients, one had been treated for a year with systemic steroids for "pseudotumor" but had myeloid leukemia, a child was treated for about 6 weeks for "pseudotumor" but had a large rhabdomyosarcoma, and the third was treated with steroids for "pseudotumor" but had a low-flow dural shunt, Dr. Rose explained.

He advised that biopsy should be considered in all patients presenting with apparent orbital inflammation and infiltrative changes on imaging, except for orbital myositis and orbital apex syndromes that follow a typical clinical course.

"I also apply the principle that I do not pre-treat infiltrative disease with steroids except for orbital myositis and orbital apex syndromes that have the very characteristic histories, clinical signs, imaging findings, and therapeutic responses. For orbital apex syndromes, the risks of biopsy are somewhat higher than the risks of missing an underlying diagnosis, and biopsy in these cases should be reserved for those that do not follow a typical inflammatory pattern. I now go as far as to say that the empirical steroid treatment of orbital disease is unjustified, confuses the diagnosis, and might be considered medico-legally negligent," he said.