Re: Qian et al.: Papilledema due to vaccine-induced thrombocytopenia (Ophthalmology. 2022;129:190).

To The Editor:

I commend the authors for reporting the ophthalmic features of a rare complication of one of the COVID-19 vaccines in their article. The authors have reported a case of vaccine-induced thrombotic thrombocytopenia (VITT) presenting to the ophthalmologist with a history of blurred vision and on examination was found to have bilateral optic disc edema with superficial peripapillary hemorrhages. The visual acuity and the visual fields were reported to be normal. The magnetic resonance imaging with a venogram of the brain revealed cerebral venous thrombosis.

There are a few clarifications required in this case to enhance the understanding of ophthalmic implications of this vaccine-related rare complication. The patient presented with a history of blurred vision, however, the visual acuity and the visual fields were reported to be normal. The ophthalmic evaluation does not explain the cause of the presenting complaint. A possible explanation is that the visual field is not absolutely normal. The visual field in the left eye is suggestive of an enlarged blind spot. Second, the fundus photo is suggestive of mild blurring of the nasal disc margins bilaterally, with superficial retinal hemorrhages around the optic disc in the left eye (pointed at with black arrow marks in Figure C in the original article). The blurring of the nasal disc margins and the retinal hemorrhages cannot be attributed to an increased intracranial pressure (ICP) alone in the absence of features suggestive of venous stasis in the form of dilated tortuous retinal vessels. The explanation could be that there are 2 different pathologies that are the manifestations of a single vaccine-related complication called VITT, which may be responsible for the papilledema and retinal hemorrhages. The papilledema is probably caused by the increased ICP secondary to the cerebral venous thrombosis, but the retinal hemorrhages are caused by thrombocytopenia. The onset of thrombosis in these cases (VITT) is typically 1–2 weeks after vaccination and almost all are accompanied by thrombocytopenia. Although thrombocytopenia alone is rarely sufficient to cause significant retinal hemorrhages, if combined with anemia, it is a known risk factor for the retinal hemorrhages in patients with idiopathic thrombocytopenic purpura. There is another similar hematologic entity known as Moskowitz’s disease or thrombotic thrombocytopenic purpura. Percival’s classic paper suggests the retinal hemorrhages in thrombocytopenic purpura are seen in 20% of cases and are suspected to be due to the microangiopathy associated with the disease.

Last, it would make the reporting more accurate if it included magnetic resonance imaging features suggestive of raised ICP such as flattening (denting) of the posterior sclera, widening of the perioptic space (subarachnoid), and vertical tortuosity of the orbital optic nerve. Because the bilateral disc edema in this case is very subtle, a mention of the cerebrospinal fluid opening pressure after lumbar puncture will definitely aid in confirming the diagnosis of an increased ICP.