Floaters in a young woman

by Juan Ding, OD, PhD

Walk in patients are fun, especially on a Friday.

27 year old female walked in our open access clinic today, reporting seeing floaters for 1 month in the left eye which bothered her. Otherwise she had no change in vision and no pain. She did not see any flashes. She saw 20/15 each eye and had normal eye pressures. Right eye was completely normal. The left eye had numerous deposits on the back side of the cornea, called KPs, and a few cells floating in the anterior chamber. There were numerous cells in the vitreous. There were two black scars in the retina close to the macula, and a fluffy white lesion with smaller (satellite) white lesions surrounding it. The retinal blood vessels and other parts of the retina, as well as the optic nerve, looked normal (photo below).


Figure 1. Fundus image showing inactive scars (arrow heads) and an active lesion (arrow).


What is your diagnosis?

On questioning, she admitted to be told to have toxoplasmosis in her left eye in 2015 when she had an eye exam for doing refractive surgery. She was told it was stable before and after her photorefractive keratectomy (PRK) surgery.

Apparently toxoplasmosis has reactivated in her left eye. “Most of the recurrences occur in the second and third decades of life in immunocompetent individuals, and may be triggered by stress or other factors.” according to an American Academy of Ophthalmology article (https://www.aao.org/current-insight/management-of-ocular-toxoplasmosis).

Toxoplasmosis is acquired by eating raw or undercooked meat, vegetables or milk products, or by coming into contact with infected cat litterbox or sandboxes, but contaminated water source has also been linked. Toxoplasmosis can also be congenital, when infection in pregnant women transfer to the fetus.

The treatment for ocular toxoplasmosis can be observation only if the lesion is peripheral and small, as in healthy people this will usually resolve without affecting vision. But if it threatens vision, such as when lesion is close to the macula or optic nerve is involved, or macular edema is present, systemic antibiotics and corticosteroid treatment are usually needed. Topical steroid is also used in the case of anterior uveitis (such as in our patient).

So not all floaters are age-related normal phenomenon.

Swollen optic nerves

I am trying to cure my cancer of laziness. So here it goes.

This morning a 26- year old woman came in. Her PCP referred her for eye exam due to headache. She has always suffered from headache since age 8, but recent 5 years it has become worse, sometimes lasting the whole day, and sleeping did not make it better. Initially OTC excedrin helped, but now does not work that well. Her vision is blurry sometimes. She used to wear prescription glasses for reading, but hasn’t for a long time, and now wearing those glasses did not seem to help either. This is an obese female, takes birth control pills, and has a history of type 2 diabetes during pregnancy which resolved since giving birth.

I see a lot of referrals for headache. Almost always the eyes are completely normal. Sure this patient fits the classic “fat fertile female” for idiopathic intracranial hypertension (IIH), but I have seen too many demographics like this that have optic nerves as flat as a shirt. So no expectations here.

However, her optic nerves look slightly elevated. And OCT confirmed thickened retinal nerve fiber layer in some quadrants.

So I guess finally another classical case. I say another because to be fair, this does happen from time to time among the numerous headache patients.


Papilledema due to IIH is often first discovered by eye doctors, because of swollen optic nerves. Patients will then need to go through brain MRI to look for possible mass lesions or blockage of the venous drainage. If none of these, lumbar puncture is done to check for opening pressure of the cerebrospinal fluid (CSF) and look for signs of infection or inflammation in the CSF. If pressure is high but CSF is clear, then a diagnosis of IIH can be made. Patients may be prescribed diamox, which is a carbonic anhydrase inhibitor that reduces CSF pressure; and encouraged to lose weight because for unknown reason, IIH strongly associates with being over-weight. Papilledema usually does not affect vision, but chronic cases may lead to visual field loss and even reduced visual acuity. So we are always on the lookout for optic nerve edema in a patient with headache.

Hallucination day

I will try to write about one interesting eye case that I see each day. (Though I have been guilty of not updating this for a long time, not for lack of cases, but due to my own laziness.) The purpose is to provide education of eye diseases, vision function and eye care to the public, and maybe to students who study optometry.


You know that sometimes unusual cases happen in clusters, like when you see three central serous retinopathy or two posterior polymorphous corneal dystrophy patients on the same day? Obviously if you are a tertiary referral center then that can be common, but for a primary eye care practice, it can be striking. I just saw two patients with visual hallucination today, that’s about the total number of hallucination cases I have ever seen since starting this primary eye care clinic 2 years ago.

68 year old lady stated she was seeing a woman in old fashioned clothes climbing a ladder in her living room, and specifically the woman had very hairy legs. She knew it was a hallucination, and went to ED for it. She was hospitalized for a few days for stroke workup including brain CT and then MRI; saw a cardiologist and then a neurologist. She told me 5 doctors were working on this for her. She had a few systemic issues including diabetes but she was not taking any medications as she stopped all these sometime ago. Anyway it turns out her visual hallucination is most likely a result of Charles Bonnet Syndrome, since her left eye has developed a dense cataract with a visual acuity of 20/80, and this moderate vision loss led to visual release hallucination. She is going to call her cataract surgeon for an evaluation.

At 3 PM a 59 old guy walked in per his cardiologist’s urgent referral. Cardiologist told me it’s a loss of vision post operation, so my immediate thought went to optic neuropathy or central retinal artery occlusion (CRAO) or something along that line. His left eye had a stick penetrating as a child and could never see much since then. Right eye was the good eye. So I assumed that his left eye was not seeing well now. So when he read 20/15 on the eye chart, I almost threw him out- this guys sees better than a 30 year old, why wasting my time? On further questioning, he admitted it’s not that the right eye was not seeing well, rather his left eye started seeing too much that bothered him. This made no sense. It was only in hindsight that I realized why he was being so vague about his symptoms. First, hallucinations are things that do not follow logic or make sense; 2nd, people in general feel embarrassed when talking about their hallucinations for fear they will be thought of as crazy. Eventually I got the story out of him. Last Monday he had a heart surgery and was released home last Friday, when he started noticing seeing colors like through prism glasses and all sorts of shapes like pumpkin and so on. He noticed these in his weak left eye but also in the normal right eye. Only when he closed both eyes did they go away. This was concerning to him because when he talked with people he would see these things on people’s faces and made it hard for him to focus.

You may guess the rest of the eye exam. Yes he had completely normal eye health in the right eye, and left eye was aphakic (having no lens) and had glaucoma but he’s seeing an outside eye doctor every 3 months for this and his eye pressure today was 16 (normal).

Could it be Charles Bonnet after so many years of poor vision in that left eye? Maybe. Was it a coincidence that he started this after a major surgery? Not sure. Since he did take multiple medications (quite a few medications including some hypertension meds, antidepressants, even some antibiotics are associated with visual hallucinations), and it’s after a heart surgery, I referred him to see a neurologist to rule out other causes of hallucinations.

Charles Bonnet Syndrome was first described by Charles Bonnet, a Swiss philosopher, who witnessed his near-blind grandfather seeing things that were not there. These hallucinations happen because of lack of visual input to the brain to suppress certain spontaneous firing of visual cortex neurons. Any form of visual loss may cause it, but commonly conditions such as age-related macular degeneration, glaucoma, dense cataract, etc are associated with Charles Bonnet Syndrome. By the way, with both my patients today visual hallucination was not associated with auditory or other sensory hallucinations, and patients were aware that these things they saw were not real. These were additional criteria for Charles Bonnet Syndrome.