The front of a patient's eye can look striped like a candy cane: a pale, khaki-colored band of cells resting on a heavier layer of fresh red blood. A recent clinical image in JAMA Ophthalmology, titled "Candy-Stripe Sign in Ghost Cell Glaucoma," put that pattern on display.
The khaki layer is made of ghost cells, worn-out red blood cells that can jam the eye's drainage system and drive pressure dangerously high. Surgery and injury are the best-known ways they escape into the front of the eye. A less familiar trigger is an injection that many people with diabetic eye disease receive. In one study of eyes with severe diabetic eye disease and long-standing bleeding, about 1 in 9 developed ghost cell glaucoma within two days of such a shot.
Khaki Cells Stacked on Fresh Blood
Ghost cells form when blood that has leaked into the vitreous, the clear gel filling the back of the eye, begins to break down. In the days after a bleed, red blood cells spread through the vitreous and gradually lose their hemoglobin. According to EyeWiki, the American Academy of Ophthalmology's clinical reference, the resulting cells are generally 4 to 7 micrometers across and "less pliable/more rigid than normal RBCs."
Healthy red cells can squeeze through the eye's drainage meshwork. Stiff ghost cells cannot, so they clog it and fluid backs up.
The stripes appear when old and new blood share the same space. EyeWiki describes "the lighter khaki-colored layer of ghost cells appearing on top of a heavier, fresh RBC layer, imparting a candy-striped appearance." The lighter cells float above because they are less dense.
An Eye Injection Can Push Ghost Cells Forward
Ghost cells normally stay behind the anterior hyaloid, a thin membrane at the front of the vitreous. Trouble begins when that barrier is disrupted, which is why surgery and trauma are well-known triggers.
A 2020 study in BMC Ophthalmology from the Beijing Tongren Eye Center pointed to another. Researchers followed 71 eyes of 68 patients with proliferative diabetic retinopathy, an advanced form of diabetic eye disease, and bleeding inside the eye. Each eye received an injection of ranibizumab, an anti-VEGF drug, before planned vitrectomy surgery.
Eight of those eyes, about 11%, developed ghost cell glaucoma within two days. Two had pressure above 30 mmHg within 30 minutes of the injection. Four were normal at 30 minutes but developed the condition within a day, and two more developed it between 24 and 48 hours after the shot. The average peak pressure reached 46.5 mmHg, more than double the normal range of about 10 to 20 mmHg.
The authors proposed that a large load of pre-existing ghost cells, the disturbance of fluid in the vitreous and brief pressure changes during the injection may push ghost cells forward. They wrote that the transient pressure rise "may damage the anterior hyaloid surface of the vitreous body." Five patients were treated with pressure-lowering drops, and three also needed a small procedure to release fluid from the front of the eye. All reached normal pressure after vitrectomy without pressure-lowering medicine.
Why the Finding Has Limits
The study was small and limited to eyes with severe diabetic disease and existing bleeding. It does not show that anti-VEGF injections are risky for typical patients. These drugs are a standard treatment for diabetic eye disease, and a major U.S. clinical trial published in JAMA found ranibizumab to be a reasonable alternative to laser treatment for proliferative diabetic retinopathy, at least through two years.
The Beijing team's advice was specific: doctors should pay attention to eye pressure in patients with proliferative diabetic retinopathy who receive an anti-VEGF injection before vitrectomy.
The JAMA Ophthalmology image does not tie its patient's case to an injection. The image serves as a visual clue that old blood has escaped from the back of the eye into the front, whatever the cause.
Pressure Usually Falls Once the Source Clears
Ghost cell glaucoma was first described by Campbell and colleagues in 1976. It was once called "hemophthalmitis," a misnomer because there is often no active inflammation. A red, painful eye full of cells can still be mistaken for uveitis, an inflammatory eye disease. EyeWiki lists clues that point to ghost cells, including a quiet conjunctiva and the absence of keratic precipitates, inflammatory deposits on the back of the cornea. Doctors can confirm the diagnosis by examining a tiny sample of fluid from the front of the eye under phase-contrast microscopy.
Treatment starts with drugs that lower eye pressure. If those fail, surgeons can wash the cells out of the front chamber, remove the blood-filled vitreous through vitrectomy or create a new drainage path. EyeWiki describes the condition as "typically transient," though it can take many months to fully resolve. Prolonged high pressure can damage the optic nerve, so recognizing the problem quickly matters.
People with diabetic eye disease, a recent eye bleed, recent eye surgery, an eye injection or an eye injury should seek prompt care for sudden eye pain, redness or blurred vision. Those symptoms have many possible causes, and only an eye exam can sort them out.
Key Questions Answered
What is the candy-stripe sign?
It is a layered look in the front of the eye, with pale khaki ghost cells sitting above heavier fresh red blood cells. It points to ghost cell glaucoma.
What are ghost cells?
They are aging red blood cells from a bleed inside the eye. They lose their hemoglobin and become rigid, which lets them clog the eye's drainage tissue.
Can eye injections trigger ghost cell glaucoma?
In a 2020 Beijing study, 8 of 71 eyes with proliferative diabetic retinopathy and bleeding developed it within two days of an anti-VEGF injection given before surgery. The findings apply to that high-risk group.
Should patients avoid anti-VEGF injections?
No. The study does not support stopping them. Its authors recommended closer pressure monitoring in high-risk patients. Treatment decisions belong with an eye specialist.
How is ghost cell glaucoma treated?
Pressure-lowering medications come first. Washing out the front chamber, vitrectomy or drainage surgery may be needed if pressure stays high.
When should someone seek care?
Anyone with sudden eye pain, redness, or blurred vision should get prompt care, especially after an eye bleed, surgery, injection, or injury.
Published by Medicaldaily.com
