Sudden Grayish Ovals in Vision: Possible Causes and Concerns - Ophthalmology

A sudden appearance of a flat oval-shaped "mosaic/ground glass" grayish-white shadow in the right eye?

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Hello Doctor: My left eye is hyperopic at +2.25 diopters, and my right eye is myopic at -6.25 diopters.
Due to severe astigmatism in my left eye, I have some amblyopia and primarily rely on my right eye for vision.
A year and a half ago, I discovered that my intraocular pressure was very high, and I have since been regularly visiting a clinic to obtain eye drops (Tafluprost) to manage my eye pressure.
In April of this year, during an examination at a regional hospital, it was noted that the optic nerves in both eyes were slightly thinner at the top, and there was a minor congenital cataract, but neither condition affected my vision.
The doctor indicated that I should continue to be monitored.
During a follow-up appointment on July 15, my condition remained unchanged, with an intraocular pressure of 22 mmHg before accounting for corneal thickness and 19 mmHg after.
However, on July 18 during the day, I felt a foreign body sensation in my right eye, so I rubbed it, which led to a sharp pain near the eye socket, but it resolved shortly after.
In the afternoon, I suddenly experienced a bit of dizziness (which occurs about once every 1-2 months), lasting less than 3 minutes before subsiding.

On the night of July 18 at 11 PM, I suddenly noticed a flat, oval-shaped grayish-white shadow in the upper right part of my central vision (not covering the central vision).
It resembled a mosaic or frosted glass effect, creating a grayish-white overlay in my field of vision.
The area was not very large, and it moved with my eye movements; I could also see it when my eyes were still.
It did not disappear temporarily with eye movements or relaxation.
When reading, it obscured the upper right part of the next one or two characters, making the letter "O" appear like a "C" with a gap in the upper right, and the horizontal line above the character "二" was reduced to just a small portion on the left.
In bright outdoor light, when looking at white lines on the ground, the shadow appeared grayish-black or gray-brown, and when looking at the blue sky, it also appeared grayish-black or gray-brown.

On the morning of July 19, I visited an ophthalmology clinic, where my intraocular pressure was measured at 22 mmHg (not accounting for corneal thickness).
I underwent fundus photography and dilated fundus examination, and the clinic doctor reported no signs of inflammation, with no issues found in the retina, optic nerve, or macula.
I was also not informed of any vitreous opacities or floaters, and the doctor suggested that if I wanted a detailed assessment, I should go to a larger hospital, providing me with a referral and advising me to observe for a few days.

In the afternoon of July 19, I visited the ophthalmologist at the regional hospital I had previously seen.
After a dilated fundus examination, the doctor checked every corner of my eye but found no issues.
I was then scheduled for an OCT scan and noticed that the shadow was more pronounced when I focused on the central red cross of the instrument, closely adjacent to the upper right area of the cross (very close to the center).
After carefully reviewing the OCT images, the regional hospital doctor confirmed that my macula showed no edema or lesions, the retina and optic nerve were normal, and there were no white spots or signs of inflammation.
The doctor noted that the vitreous might "suspect" some opacities and advised me to observe for a week before returning for a follow-up, with the diagnosis recorded as ocular hypertension, without mentioning any vitreous opacities.

In the past six months, I have been going to bed very late (but I usually get about 8 hours of sleep), and I have been using my eyes more than usual.
I have speculated whether this could simply be eye fatigue or floaters, but this condition has persisted for a full two days now.
If it were eye fatigue, it shouldn't last this long, and the grayish-white/gray-black shadow I see is different from typical floater symptoms.
If it were floaters, both doctors should have directly informed me of that after the dilated fundus examination, and the regional hospital doctor did not record it as vitreous opacities, only suggesting to observe for a week before considering a referral to a neurologist.

I primarily rely on my right eye for vision, and now I am suddenly troubled and worried by an unexplained grayish-white/gray-black shadow in that eye.
Last night, I researched some cases and found a case report from Taipei City Hospital where a patient had similar complaints and was ultimately diagnosed with "posterior vitreous detachment." However, since the regional hospital performed an OCT scan, they should have been able to identify that condition as well.

My questions are as follows:
1.
Have you encountered similar cases before? What is the most likely cause of this condition?
2.
Is it possible that there is an issue with the pre-macular bursa? If there is a problem in that area, can an ophthalmologist detect it through examination?
3.
Could this be related to a neurological issue in the brain?
Thank you, Doctor.

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Mr. N, 20~29 year old female. Ask Date: 2021/07/20