Swelling of the Optic Nerve Head: A Backstage View of a Staging Scheme

In the late 1960s, the daily routines of this neuro-ophthalmologist-wannabe at the Sahlgren University Hospital in Gothenburg, Sweden, then one of Europe's largest, included running around on the neurology and neurosurgery wards to help monitor patients with high intracranial pressure. This was long before anyone had heard of bedside fundus photography, much less computed imaging, or continuous intracranial direct pressure measurements. Many of my neurology and neurosurgery colleagues were quite accomplished ophthalmoscopists, but they also were well aware of the wide variations between examiners. Some categorized optic disc swelling in vague terms such as 'incipient,' 'moderate,' 'florid,' 'choked' or 'vintage.' Others concentrated on protrusion, which was roughly and highly variably estimated in terms of dioptric elevations. Some paid much attention to venous pulsations, whereas others relied on the prominence of small vessels at the disc border. With my ophthalmology background, I preferred the arcane technique of monocular indirect ophthalmoscopy, which offered a better overview than the direct counterpart, even with small pupils. Still, terminology remained a major obstacle to reproducible evaluations. The first hints of better prospects came from a somewhat unexpected direction, namely, novel funduscopic observations of optic atrophy. Using a green filter to produce so- called red-free illumination, William F Hoyt, MD, at the University of California at San Francisco had found a way to visualize the peripapillary part of the retinal nerve fiber layer and the changes that occur with optic atrophy.