Eye Dictionary: O-P
O
OCT. Also known as Optical Coherence Tomography, this is a machine used to take a picture and "map" the surface contour of the retina. It works very similar to ultrasound, but instead of using sound, light waves are bounced off the internal eye structures. The scans produced by this machine look similar to that produced by a sonar depth finder in a boat ... but instead of mapping the bottom of the ocean or river bed, we are measuring the surface of the retina (which is supposed to be flat and smooth like film in a camera). OCT is useful for detecting retinal distortions (like those caused by an epiretinal membrane) and for looking for macular edema in cases of wet macular degeneration or diabetic retinopathy. The OCT can also be used to map the optic nerve and is helpful for documenting and monitoring for glaucoma nerve damage (i.e., glaucomatous cupping).
ocular migraine. This is a migraine that either affects the vision (causing a migraine aura) or creates pain specifically in the eye. See migraine aura for more information on this topic.
Ocuflox. This is the trade name for the antibiotic eye drop ofloxacin. Ofloxacin is a moderately strong fluoroquinolone used for eye infections and prophylactic treatment after cataract surgery.
OCuSOFT. This is a brand of pre-made lid scrubs used for the treatment of blepharitis. These pre-moistened pads are used to gently clean debris off the eyelashes, improving lid hygiene, and making the eyes less irritable. These scrubs can sometimes be hard to find in stores, but are easily found online at Amazon.com. Other companies have begun making similar pads such as Systane Lid Wipes.
Ocuvite. This is an eye vitamin, produced by Bausch and Lomb, designed to decrease progression of aging changes from macular degeneration. This vitamin formula was created after the AREDS Study showed that certain antioxidants slowed the progression of macular degeneration changes in the retina. This original formula consisted of vitamins A (beta-carotene), C, E and the minerals zinc and copper. Since Bausch & Lomb helped supply the original formula (along with the National Eye Institute), they immediately patented the combination and now sell the vitamin with a costly markup. Other companies have reached settlements with B&L and sell similar vitamins under different brands such as I-CAPS. Due to new research (and market pressures) the original formula is changing with the addition of lutein, zeaxanthin, and Omega-3 oils added to the mix. These additional supplements have been studied in the follow-up AREDS 2 Study.
ofloxacin. This is an antibiotic eye drop, also sold under the trade name Ocuflox. It is used for bacterial eye infections and often used as a prophylactic antibiotic before and after cataract surgery. This is a second generation fluoroquinolone similar to ciprofloxacin.
omega-3. These are fatty acids obtained from deep sea fish. There is some thought that Omega-3 supplements may help with macular degeneration, but they haven't been as beneficial as once hoped (see the AREDS 2 Study). Also, these fatty acids improve oil flow in the skin and may help with dry eye and the meibomian gland dysfunction found in blepharitis. The two types of Omega-3 acids most studied are the DHA and EPA variety. The best source is cold water fish such as salmon,
tuna, herring, and (yuck) sardines. If you aren't a fish lover, omega-3s are available as supplements, both in oil and pill form. Vegetarians can get omega-3s from flaxseed, walnuts, and dark leafy vegetables.
Omnipred. This is the trade name for the steroid eye drop prednisolone acetate. Other names for this drop are Pred Forte and Econopred. This is a powerful topical steroid used to cool down inflammation. It is also used after cataract surgery to cool down inflammation and speed healing.
Opcon-A. This is an over-the-counter allergy drop used for itching and swelling of the eyelids. This drop is the same as the competing brand Naphcon-A. Opcon-A contains both an antihistamine and a vasoconstrictor. While effective for short term relief, I prefer the more powerful second generation allergy drops like Alaway/Zaditor and Patanol.
ophthalmologist. This is a doctor who treats medical eye problems and performs laser and eye surgery. An ophthalmologist completes a four-year undergraduate degree with a focus on "pre-med" subjects including biology, chemistry, and physics. They then complete a four-year medical school program, working in a teaching hospital to become a medical doctor (MD). After this, we typically complete a year-long internship in a hospital rotating through inpatient wards, ICUs, and emergency rooms. We then proceed to an intense three-year residency eye program focusing on medical and surgical treatment of eye disease. Finally, some ophthalmologists take on an additional 1-2 years to sub-specialize in retina, cornea, glaucoma, etc.
optic disk. This is the insertion point of the optic nerve into the back of the eye. The optic nerve is a large nerve that connects the eyeball to the brain. This nerve inserts on the back of the eyeball and looks like a tube or pipe piercing the back of the eye. We can see the nerve insertion inside the eye during a dilated retina exam. Because we are viewing the nerve straight on it looks like a circle or a "disk" sitting in the middle of the retina. Examination of the disk is useful for monitoring many problems. For example, with glaucoma high ocular pressure slowly kills off the individual nerve fibers that fill the optic nerve. This creates a hollowed out area or "cup" that can be seen in the middle of the optic disk. This is called glaucomatous cupping and we follow the "cupping to disk ratio" over time to monitor for glaucoma damage. With pseudotumor cerebri, the pressure inside the skull (intracranial pressure) is high. This causes headaches and potentially neurologic problems if left untreated. The intracranial pressure is hard to measure, however, short of performing a spinal tap. However, this pressure can sometimes be seen at the optic disk because the fluid pressure can flow down the optic nerve and appear as optic disk swelling inside the eye.
optic nerve. The optic nerve is the large nerve that connects the eyeball to the brain. This nerve is actually comprised of over a million individual nerve fibers that send visual signals from the retina to the brain for processing. This nerve is obviously important and several eye diseases can affect it. The most common one is glaucoma. Glaucoma occurs when the internal eye pressure is too high, causing the death of the nerve fibers over time. Another optic nerve disorder we see is called optic neuritis. This is an inflammation of the optic nerve and is sometimes associated with multiple sclerosis (which causes inflammation of nerves in the brain as well). An ION (ischemic optic neuropathy) is like a mini-stroke to the optic nerve and occurs when the blood supply to the nerve is temporarily compromised. While most of the optic nerve is located behind the eyeball, a small portion can be seen from inside the eye as the optic disk.
optic nerve drusen. These are calcium crystals that form in the optic nerve and give the illusion of optic nerve swelling. The optic nerve is the large nerve that connects the eyeball to the brain. This nerve enters the back of the eye and this insertion can be seen inside the eye as the optic disk. Some people have natural calcium crystal deposits that form inside their optic disk. These calcium deposits are bulky, taking up space and giving the illusion of optic nerve swelling (papilledema). Swelling is a big deal as dangerous conditions like pseudotumor cerebri (high pressure inside the skull) can cause t rue optic nerve swelling. It is not always easy to differentiate between optic nerve drusen and true edema. In adults, drusen are easy to diagnose as the crystals glow and look like clusters of shiny rocks embedded in the nerve. In younger people the diagnoses is harder as the crystals are buried deeply and not as discernable. To truly detect optic nerve drusen, a number of tests can be performed. We can ultrasound the eye and look for the crystals - as the drusen are made of calcium, sound waves bounce off them and show up brightly on an ultrasound picture. A more invasive CAT scan can also be obtained as the crystals light up just like calcium-filled bones do. Another detection method is with a fluorescein angiogram. This test involves injection of a yellow dye into the blood stream to look for leakage inside the retina and optic nerve - calcium crystals don't leak fluid, while true optic nerve swelling does. While usually harmless, optic nerve drusen can cause problems with the peripheral vision, so a visual field test is sometimes obtained to establish a good baseline.
optic neuritis. This is an inflammation of the optic nerve that causes vision loss and occasionally eye pain. The optic nerve is the large nerve that connects the eye to the brain. Inflammation of this nerve will cause vision problems such as an enlarged blind spot and decreased
vision. Optic neuritis occurs more in younger people (under 50) and is sometimes a harbinger of more serious inflammatory nerve disorders like multiple sclerosis. Nerve swelling can sometimes be seen by the eye doctor by looking at the optic disk in the back of the eye. However, most of the optic nerve is located behind the eye and only a small portion of the nerve can actually be visualized during a dilated eye exam. Other hints of nerve swelling are pupil abnormalities and decreased color
vision. More definitive diagnosis can be made by MRI, which is also useful for detecting other lesions in the brain consistent with multiple sclerosis. Treatment usually involves referral to a neurologist with possible IV steroids or other anti-inflammatory medicines. The vision usually comes back over a few weeks or months, though some permanent vision loss can occur.
optical coherence tomography. An eye test that uses light waves to measure the surface of the retina ... similar to using sonar or ultrasound to measure the bottom of the ocean. See OCT for more information on this common test.
optician. This is a person who fits and dispenses glasses and other corrective visual devices. Once you have a glasses prescription (from an optometrist or ophthalmologist) this is the person who actually measures your face and fits your glasses. They measure your pupillary distance, vertex distance, and determine where your bifocal should sit. They build the glasses and make sure they work properly.
Optivar. This is the trade name for the antihistamine azelastine. This is a prescription allergy drop, used for itching and swelling of the eyes and eyelids. I've never prescribed this, given the ready supply of other allergy drops like Bepreve, Pataday and over-the-counter drops like Alaway/Zaditor.
optometrist. A doctor of optometry specializes in primary eye care with a focus on refractive correction (glasses and contacts). These doctors typically complete a 4-year undergraduate degree, before going on to 4 more years of optometry graduate school. After this, an optometrist may go directly into practice or complete further residency training if they have an interest in a specific fields of interest (like pediatrics or low-vision). An optometrist has an O.D. doctorate degree, and while they don't perform surgical procedures, they are licensed in most states to prescribe eye drop medications and therapeutic treatments. They are very good at optical correction and the fitting of challenging glasses and contact lenses. In many ways, the optometrist is like the "family practitioner" of the eye world - they are often the first person to detect new eye problems and will refer medical/surgical problems to the appropriate ophthalmologist (general or sub-specialist) when warranted.
ocular migraine. This is a migraine that either affects the vision (causing a migraine aura) or creates pain specifically in the eye. See migraine aura for more information on this topic.
Ocuflox. This is the trade name for the antibiotic eye drop ofloxacin. Ofloxacin is a moderately strong fluoroquinolone used for eye infections and prophylactic treatment after cataract surgery.
OCuSOFT. This is a brand of pre-made lid scrubs used for the treatment of blepharitis. These pre-moistened pads are used to gently clean debris off the eyelashes, improving lid hygiene, and making the eyes less irritable. These scrubs can sometimes be hard to find in stores, but are easily found online at Amazon.com. Other companies have begun making similar pads such as Systane Lid Wipes.
Ocuvite. This is an eye vitamin, produced by Bausch and Lomb, designed to decrease progression of aging changes from macular degeneration. This vitamin formula was created after the AREDS Study showed that certain antioxidants slowed the progression of macular degeneration changes in the retina. This original formula consisted of vitamins A (beta-carotene), C, E and the minerals zinc and copper. Since Bausch & Lomb helped supply the original formula (along with the National Eye Institute), they immediately patented the combination and now sell the vitamin with a costly markup. Other companies have reached settlements with B&L and sell similar vitamins under different brands such as I-CAPS. Due to new research (and market pressures) the original formula is changing with the addition of lutein, zeaxanthin, and Omega-3 oils added to the mix. These additional supplements have been studied in the follow-up AREDS 2 Study.
ofloxacin. This is an antibiotic eye drop, also sold under the trade name Ocuflox. It is used for bacterial eye infections and often used as a prophylactic antibiotic before and after cataract surgery. This is a second generation fluoroquinolone similar to ciprofloxacin.
omega-3. These are fatty acids obtained from deep sea fish. There is some thought that Omega-3 supplements may help with macular degeneration, but they haven't been as beneficial as once hoped (see the AREDS 2 Study). Also, these fatty acids improve oil flow in the skin and may help with dry eye and the meibomian gland dysfunction found in blepharitis. The two types of Omega-3 acids most studied are the DHA and EPA variety. The best source is cold water fish such as salmon,
tuna, herring, and (yuck) sardines. If you aren't a fish lover, omega-3s are available as supplements, both in oil and pill form. Vegetarians can get omega-3s from flaxseed, walnuts, and dark leafy vegetables.
Omnipred. This is the trade name for the steroid eye drop prednisolone acetate. Other names for this drop are Pred Forte and Econopred. This is a powerful topical steroid used to cool down inflammation. It is also used after cataract surgery to cool down inflammation and speed healing.
Opcon-A. This is an over-the-counter allergy drop used for itching and swelling of the eyelids. This drop is the same as the competing brand Naphcon-A. Opcon-A contains both an antihistamine and a vasoconstrictor. While effective for short term relief, I prefer the more powerful second generation allergy drops like Alaway/Zaditor and Patanol.
ophthalmologist. This is a doctor who treats medical eye problems and performs laser and eye surgery. An ophthalmologist completes a four-year undergraduate degree with a focus on "pre-med" subjects including biology, chemistry, and physics. They then complete a four-year medical school program, working in a teaching hospital to become a medical doctor (MD). After this, we typically complete a year-long internship in a hospital rotating through inpatient wards, ICUs, and emergency rooms. We then proceed to an intense three-year residency eye program focusing on medical and surgical treatment of eye disease. Finally, some ophthalmologists take on an additional 1-2 years to sub-specialize in retina, cornea, glaucoma, etc.
optic disk. This is the insertion point of the optic nerve into the back of the eye. The optic nerve is a large nerve that connects the eyeball to the brain. This nerve inserts on the back of the eyeball and looks like a tube or pipe piercing the back of the eye. We can see the nerve insertion inside the eye during a dilated retina exam. Because we are viewing the nerve straight on it looks like a circle or a "disk" sitting in the middle of the retina. Examination of the disk is useful for monitoring many problems. For example, with glaucoma high ocular pressure slowly kills off the individual nerve fibers that fill the optic nerve. This creates a hollowed out area or "cup" that can be seen in the middle of the optic disk. This is called glaucomatous cupping and we follow the "cupping to disk ratio" over time to monitor for glaucoma damage. With pseudotumor cerebri, the pressure inside the skull (intracranial pressure) is high. This causes headaches and potentially neurologic problems if left untreated. The intracranial pressure is hard to measure, however, short of performing a spinal tap. However, this pressure can sometimes be seen at the optic disk because the fluid pressure can flow down the optic nerve and appear as optic disk swelling inside the eye.
optic nerve. The optic nerve is the large nerve that connects the eyeball to the brain. This nerve is actually comprised of over a million individual nerve fibers that send visual signals from the retina to the brain for processing. This nerve is obviously important and several eye diseases can affect it. The most common one is glaucoma. Glaucoma occurs when the internal eye pressure is too high, causing the death of the nerve fibers over time. Another optic nerve disorder we see is called optic neuritis. This is an inflammation of the optic nerve and is sometimes associated with multiple sclerosis (which causes inflammation of nerves in the brain as well). An ION (ischemic optic neuropathy) is like a mini-stroke to the optic nerve and occurs when the blood supply to the nerve is temporarily compromised. While most of the optic nerve is located behind the eyeball, a small portion can be seen from inside the eye as the optic disk.
optic nerve drusen. These are calcium crystals that form in the optic nerve and give the illusion of optic nerve swelling. The optic nerve is the large nerve that connects the eyeball to the brain. This nerve enters the back of the eye and this insertion can be seen inside the eye as the optic disk. Some people have natural calcium crystal deposits that form inside their optic disk. These calcium deposits are bulky, taking up space and giving the illusion of optic nerve swelling (papilledema). Swelling is a big deal as dangerous conditions like pseudotumor cerebri (high pressure inside the skull) can cause t rue optic nerve swelling. It is not always easy to differentiate between optic nerve drusen and true edema. In adults, drusen are easy to diagnose as the crystals glow and look like clusters of shiny rocks embedded in the nerve. In younger people the diagnoses is harder as the crystals are buried deeply and not as discernable. To truly detect optic nerve drusen, a number of tests can be performed. We can ultrasound the eye and look for the crystals - as the drusen are made of calcium, sound waves bounce off them and show up brightly on an ultrasound picture. A more invasive CAT scan can also be obtained as the crystals light up just like calcium-filled bones do. Another detection method is with a fluorescein angiogram. This test involves injection of a yellow dye into the blood stream to look for leakage inside the retina and optic nerve - calcium crystals don't leak fluid, while true optic nerve swelling does. While usually harmless, optic nerve drusen can cause problems with the peripheral vision, so a visual field test is sometimes obtained to establish a good baseline.
optic neuritis. This is an inflammation of the optic nerve that causes vision loss and occasionally eye pain. The optic nerve is the large nerve that connects the eye to the brain. Inflammation of this nerve will cause vision problems such as an enlarged blind spot and decreased
vision. Optic neuritis occurs more in younger people (under 50) and is sometimes a harbinger of more serious inflammatory nerve disorders like multiple sclerosis. Nerve swelling can sometimes be seen by the eye doctor by looking at the optic disk in the back of the eye. However, most of the optic nerve is located behind the eye and only a small portion of the nerve can actually be visualized during a dilated eye exam. Other hints of nerve swelling are pupil abnormalities and decreased color
vision. More definitive diagnosis can be made by MRI, which is also useful for detecting other lesions in the brain consistent with multiple sclerosis. Treatment usually involves referral to a neurologist with possible IV steroids or other anti-inflammatory medicines. The vision usually comes back over a few weeks or months, though some permanent vision loss can occur.
optical coherence tomography. An eye test that uses light waves to measure the surface of the retina ... similar to using sonar or ultrasound to measure the bottom of the ocean. See OCT for more information on this common test.
optician. This is a person who fits and dispenses glasses and other corrective visual devices. Once you have a glasses prescription (from an optometrist or ophthalmologist) this is the person who actually measures your face and fits your glasses. They measure your pupillary distance, vertex distance, and determine where your bifocal should sit. They build the glasses and make sure they work properly.
Optivar. This is the trade name for the antihistamine azelastine. This is a prescription allergy drop, used for itching and swelling of the eyes and eyelids. I've never prescribed this, given the ready supply of other allergy drops like Bepreve, Pataday and over-the-counter drops like Alaway/Zaditor.
optometrist. A doctor of optometry specializes in primary eye care with a focus on refractive correction (glasses and contacts). These doctors typically complete a 4-year undergraduate degree, before going on to 4 more years of optometry graduate school. After this, an optometrist may go directly into practice or complete further residency training if they have an interest in a specific fields of interest (like pediatrics or low-vision). An optometrist has an O.D. doctorate degree, and while they don't perform surgical procedures, they are licensed in most states to prescribe eye drop medications and therapeutic treatments. They are very good at optical correction and the fitting of challenging glasses and contact lenses. In many ways, the optometrist is like the "family practitioner" of the eye world - they are often the first person to detect new eye problems and will refer medical/surgical problems to the appropriate ophthalmologist (general or sub-specialist) when warranted.