Understanding Visual Disturbances: Causes of Light Sensations and Flashes in Eyes
The eyes have a sensation of brightness? Hello Doctor: Due to years of degeneration in the central area of the retina, I have lost central vision, but my peripheral vision remains clear. 1. In a dark room, when I remain still and first look to the left before moving my eyes to th...
Dr. Zhang Yanrui reply Ophthalmology
When the retina in the eye is stimulated, it presents sensations in the form of light perception. Therefore, stimuli such as light, electricity, or pressure can all produce visual sensations. For instance, if you press on your eyeball, you will also experience light perception. I...[Read More] Understanding Visual Disturbances: Causes of Light Sensations and Flashes in Eyes
Is Eye Rubbing Causing Flashing Lights a Normal Occurrence?
Is it normal to see flashes of light when rubbing your eyes? I have had macular degeneration for several years and mild myopia of about 200-300 degrees. I visit the hospital for follow-ups every six months. Recently, I accidentally rubbed my eyes in a dimly lit environment and fe...
Dr. Zhang Yanrui reply Ophthalmology
Seeing flashes of light indicates that the retina is being stimulated, whether by light, electrical signals, or mechanical force, which can produce visual sensations. Therefore, gently pressing around the eyeball while keeping the eyes closed can also result in visual sensations,...[Read More] Is Eye Rubbing Causing Flashing Lights a Normal Occurrence?
Understanding DB in Visual Field Testing for the Visually Impaired
DB? Hello, I have a question regarding a reference I came across in literature about visual impairment. It mentions the "30-degree program check of the automated visual field center, with an average defect greater than 20 dB (not included)." I would like to understand w...
Dr. Zhang Yanrui reply Ophthalmology
dB is an abbreviation for Decibel, which is a unit of measurement based on 0.1 log. In visual field testing, the amount of light intensity that gradually decreases from the maximum illumination is expressed in dB.[Read More] Understanding DB in Visual Field Testing for the Visually Impaired
Understanding Orthokeratology: Benefits, Risks, and Legality for Kids
What is corneal reshaping? What are its advantages and disadvantages? Is it illegal? My daughter is eight years old, and her eyesight is approximately between 200 to 300 degrees. She has been wearing orthokeratology lenses for six months, but I have heard that they can cause sign...
Dr. Zhang Yanrui reply Ophthalmology
Orthokeratology lenses are actually similar to wearing rigid gas permeable contact lenses; as long as they are properly cleaned, they generally do not pose significant harm. If you get used to wearing them and have regular follow-up appointments, there is not much to worry about....[Read More] Understanding Orthokeratology: Benefits, Risks, and Legality for Kids
Understanding Post-LASIK Myopia Progression: A Patient's Concern
After LASIK, myopia continues to worsen? Dear Sir, I originally had around 1000 degrees of myopia in both eyes. After undergoing LASIK, my vision was initially clear, but this improvement did not last. In the first year, my prescription changed by 100 degrees, and it has continu...
Dr. Zhang Yanrui reply Ophthalmology
Your condition is quite complicated and may be due to pathological (progressive) high myopia or unstable refraction caused by corneal thinning. A thorough examination by a physician is necessary to determine the underlying cause, and further surgery is not recommended.[Read More] Understanding Post-LASIK Myopia Progression: A Patient's Concern
Understanding Protruding Eyes: Causes and Solutions for Myopia
Protruding eyes issue? Hello doctor, I have a myopia of -6.50 diopters with no astigmatism. Recently, I've noticed that my eyelids are becoming increasingly swollen, and my eyes are becoming more prominent. I've often heard that this is related to high myopia; is this c...
Dr. Zhang Yanrui reply Ophthalmology
If eyelid swelling can be confirmed not to be related to thyroid issues, it may be due to allergies, conjunctivitis, or lack of sleep. True exophthalmos can only be confirmed through measurements by an ophthalmologist; many patients who do not actually have protruding eyes may fe...[Read More] Understanding Protruding Eyes: Causes and Solutions for Myopia
Understanding Blindness: Definition and Vision Impairment Explained
Hello, I would like to ask about the definition of blindness? Hello Dr. Chang: I would like to ask if having a visual acuity of counting fingers at 10 centimeters after cataract surgery is considered blindness? Also, what is the definition of blindness? Thank you for taking the t...
Dr. Zhang Yanrui reply Ophthalmology
According to the definition of disability manuals, when using vision as the standard, blindness is defined as having both eyes with the better eye's vision being less than 0.1. Therefore, if one eye has poor vision but the other eye has vision better than 0.1, it cannot be c...[Read More] Understanding Blindness: Definition and Vision Impairment Explained
Why You Might Experience Eye Pain After Sleeping in Contacts
Wearing contact lenses while sleeping can sometimes cause eye pain? Dear Dr. Chang, Recently, I have been sleeping with soft contact lenses occasionally, and upon waking up, my eyes experience pain that lasts for 1-2 hours, accompanied by a runny nose. I did not have these issue...
Dr. Zhang Yanrui reply Ophthalmology
Waking up with eye pain may be due to conjunctivitis, sebaceous gland obstruction, or insufficient tear production. You may consider stopping the use of contact lenses for a week to see if there is improvement; if the conjunctivitis is caused by contact lenses, the symptoms shoul...[Read More] Why You Might Experience Eye Pain After Sleeping in Contacts
Understanding Eye Asymmetry After LASIK and PRK Surgery
My eyes... are so annoying!! Hello, I had laser eye surgery for my myopia in June and July of this year, with each eye done separately. I had LASIK on my right eye and PRK on my left eye. Everything was fine initially, but for some reason, my left eye has suddenly developed a not...
Dr. Zhang Yanrui reply Ophthalmology
Hello: Basically, the condition of your eyelids may not necessarily be related to laser surgery; it is more closely associated with neurology or oculoplastic surgery. Ptosis is not always indicative of myasthenia gravis, but it must be considered, as subsequent treatment is very ...[Read More] Understanding Eye Asymmetry After LASIK and PRK Surgery
Understanding Nasolacrimal Duct Surgery: Procedure, Anesthesia, and Risks
Dacryocystorhinostomy (DCR) surgery? Hello Dr. Chang: Could you please explain the procedure for nasolacrimal duct probing? Is general anesthesia required for patients under three years old? What are the common risks associated with this surgery? Thank you.
Dr. Zhang Yanrui reply Ophthalmology
The surgery itself is quite simple and short in duration. Initially, a probe is used to open the nasolacrimal duct, followed by the insertion of a silicone tube to maintain patency for about six months. Adults may sometimes undergo the procedure without general anesthesia, but it...[Read More] Understanding Nasolacrimal Duct Surgery: Procedure, Anesthesia, and Risks
Understanding Protruding Eyes: Causes and Solutions for Performers
About protruding eyes? Hello, doctor. I would like to ask about my condition. I have over 900 degrees of myopia, and when I take off my glasses, my friends say that my eyes look very bulging from the side, resembling "fish eyes," and they find it quite scary. So, I woul...
Dr. Zhang Yanrui reply Ophthalmology
As a patient with high myopia, your axial length is longer than that of others, which may feel unusual to most people. Once the axial length has increased, it cannot be reversed. Currently, if you prefer not to wear glasses, options include wearing contact lenses or undergoing la...[Read More] Understanding Protruding Eyes: Causes and Solutions for Performers
Understanding Black Spots in Vision After Eye Trauma: What to Know
Regarding the appearance of black spots in the visual field after trauma? I am a person with high myopia (right eye -1350, left eye -1250). A week ago, I was in a car accident and was struck by a hard object on the brow ridge above my right eye. The next day, my right eye was com...
Dr. Zhang Yanrui reply Ophthalmology
Since I cannot perform an actual examination, I can only suggest possible causes. You may be experiencing vitreous degeneration due to a trauma, commonly known as floaters. Floaters typically do not improve unless surgically removed, but surgery is not recommended because floater...[Read More] Understanding Black Spots in Vision After Eye Trauma: What to Know
Choosing the Right Intraocular Lens After Cataract Surgery
Selection of Intraocular Lenses (IOLs) Over three years ago, I underwent laser surgery for my myopia. Due to the use of steroids one month post-surgery, I developed cataracts. Recently, my vision has deteriorated rapidly, significantly affecting my daily life and work. I am curre...
Dr. Zhang Yanrui reply Ophthalmology
Actually, you can still receive coverage from the National Health Insurance, but you need to apply in advance, which takes about two to three weeks. This can save you approximately NT$30,000 in surgical fees. Additionally, you may consider using some out-of-pocket intraocular len...[Read More] Choosing the Right Intraocular Lens After Cataract Surgery
Understanding Myopia: Visual Acuity and Clarity in Close-Up Reflections
Myopia Visual acuity of 0.1 corresponds to approximately -10.00 diopters, while 0.4 corresponds to about -2.50 diopters. Regarding your second question, individuals with myopia (nearsightedness) may find it easier to see objects up close, such as their face in a mirror, compare...
Dr. Zhang Yanrui reply Ophthalmology
0.1 and 0.4 are visual acuities and do not represent the degree of myopia; myopia, hyperopia, astigmatism, and amblyopia can all result in such visual acuities. In individuals with presbyopia, specifically those over the age of forty-two, myopic individuals may see near objects m...[Read More] Understanding Myopia: Visual Acuity and Clarity in Close-Up Reflections
Latest Advances in Treatments for Retinitis Pigmentosa
Retinitis pigmentosa Are there any recent therapies for retinal pigmentosa?
Dr. Zhang Yanrui reply Ophthalmology
Currently, there are no new medical breakthroughs for pigmentary retinopathy; treatment still primarily involves ultraviolet protection and vitamin A supplementation.[Read More] Latest Advances in Treatments for Retinitis Pigmentosa
Post-LASIK Recovery: Common Concerns and Eye Health Tips
Post-LASIK complications? Hello, doctor: After undergoing LASIK surgery, how long does it take for the corneal flap to fully heal, and when can I get my eyes wet or rub them? If there are small, water-like bumps on the eyelids and if I stay up late, will this affect my vision lat...
Dr. Zhang Yanrui reply Ophthalmology
Hello: After LASIK surgery, the interface between the corneal flap and the bed will never completely heal, but this will not affect visual function or cause discomfort, so there is no need to worry. As for the corneal epithelium, it typically heals completely within three days. A...[Read More] Post-LASIK Recovery: Common Concerns and Eye Health Tips
Is Cesarean Delivery Safer for Patients with High Myopia?
Is cesarean delivery suitable for individuals with high myopia? Dear Dr. Chang: I once read a report in the newspaper stating that "patients with high myopia are at a higher risk of retinal detachment if they undergo vaginal delivery." I currently have a myopia of -8.50...
Dr. Zhang Yanrui reply Ophthalmology
Labor requires increased abdominal pressure, which theoretically could have an adverse effect on the occurrence of retinal detachment. However, current scientific research has not found a correlation between the two. Therefore, given your condition, if there is any degeneration o...[Read More] Is Cesarean Delivery Safer for Patients with High Myopia?
Understanding Red Veins in the Eyes: Causes and Contact Lens Concerns
Blood vessels in the sclera? Hello, I have been wearing bi-weekly contact lenses for six months. I heard that prolonged use of contact lenses can lead to neovascularization. I have also noticed blood vessels in the sclera and even around the cornea. Could this be neovascularizati...
Dr. Zhang Yanrui reply Ophthalmology
The so-called neovascularization caused by contact lenses occurs on the cornea, which is the surface of the iris, and cannot be seen without an ophthalmic microscope. What you are observing are the blood vessels on the conjunctiva; normally, there are many small conjunctival bloo...[Read More] Understanding Red Veins in the Eyes: Causes and Contact Lens Concerns
How Often Should You Replace Your Contact Lenses?
Contact lenses Doctor, may I ask if contact lenses should be replaced every one to two years?
Dr. Zhang Yanrui reply Ophthalmology
Yes. Contact lenses are categorized into disposable and extended wear types. Extended wear lenses are not recommended for use beyond one year, as impurities that are difficult to clean can accumulate on the surface, potentially causing eye damage. Therefore, they should be replac...[Read More] How Often Should You Replace Your Contact Lenses?
Understanding Rigid Gas Permeable Contact Lenses for High Myopia
Rigid gas permeable contact lenses Hello Doctor: I have a myopia of 800 degrees. A few days ago, I went to an optical shop to get glasses, and they told me that my eyes are very demanding on vision and will continue to deteriorate. Therefore, they recommended that I wear rigid ga...
Dr. Zhang Yanrui reply Ophthalmology
Hello: If you are over the age of 25, your vision is unlikely to change significantly unless there are some special pathological conditions. The advantage of orthokeratology lenses is that you do not need to wear contact lenses during the day, but if you stop wearing them for a w...[Read More] Understanding Rigid Gas Permeable Contact Lenses for High Myopia