DIAGNOSTIC TESTING

Dr. Najafi-Tagol is pleased to provide the finest in state-of-the-art diagnostic testing instrumentation for her patients in her commitment to Excellence in Eye Care.

Visual Field Analysis

Visual field tests allow Dr. Najafi-Tagol to examine your eyes in search of scotomas (blind spots or areas of decreased vision), which often prove to be early indicators of future eye disease. The various pattern, size, and shape of these areas can be used by Dr. Najafi-Tagol in the differential diagnosis of variety of specific eye diseases for which early treatment can be essential.

The Humphrey Field Analyzer (HFA) is a sophisticated computer-driven program that measures patient's responses to visual stimuli appearing in the peripheral vision. Patients will sit in front of a concave dome, stare at a central target within the dome and will press a button when they see small light flashes in their peripheral vision. Dr. Najafi-Tagol will compare the responses to age-matched controls to determine the presence of scotomas in the visual field.

IOL Master

When our ultimate goal in cataract surgery is to restore vision, we leave no room for error. To provide our patients with the latest advancements in eye care, Dr. Najafi-Tagol has selected the Carl Zeiss Meditec IOL Master laser system. This state-of-the-art instrument is used to evaluate the length of the eye, surface curvature and intraocular lens power.

The IOL Master offers unsurpassed precision and accuracy in providing Dr. Najafi-Tagol test results to help her determine the best course of treatment for patients. The IOL Master provides patients with safe and comfortable testing, as it is the first optical tool that doesn’t need to touch the eye, thus eliminating the need for anesthesia. IOL Master testing also provides patients with results in less than two minutes.

Fundus Photography

Fundus photography is a highly specialized form of medical imaging used to capture digital photographs of the back of the eye (fundus). These images allow Dr. Najafi-Tagol to document the health status of the optic nerve, vitreous, macula, retina and its blood vessels. Comparison of this type of doumentation enables Dr. Najafi-Tagol to track changes over time, ensuring accurate diagnosis and treatment of a patient’s eye conditions.

Photography of the patient’s eyes is best accomplished with the eyes dilated thus allowing the maximum amount of light to pass through the pupil and to the back of the eye. The patient will be asked to stare at a fixation device while the photographs are taken. The entire process normally takes approximately five to 10 minutes.

A-Scan Biometry

Also known as Axial Eye Length Biometry, this test uses sound waves (ultrasound) to measure the thickness of eye tissue. Dr. Najafi-Tagol may also use these calculations to evaluate your eye before cataract surgery. Once numbing drops are administered, a plastic fluid-filled shell is placed on the surface of the eye.

As you focus on a specific target on the ceiling, the probe is placed into the fluid, and measurements are taken. It will take approximately 15 minutes to measure each eye. The test is painless. Following the test, your eyes will be rinsed using a sterile saline solution. Do not rub your eyes for at least 30 minutes. After a 20-minute break, when your vision returns to normal, you may resume routine activities.

Autorefraction/Topography

An autorefractor is a computer-controlled device that is used to provide an approximate prescription for glasses or contacts to correct a person's refractive error. This revolutionary technology is able to provide this information by measuring how the light changes as it enters a person's eye. At the same time, the curves and contours of the corneal are assessed resulting in a topographical map.

Testing one eye at a time, the patient will look at a picture inside the instrument while several readings are taken as the picture moves in an out of focus until the image is is in clear focus on the retina. The process is simple, objective, and painless, taking only a few minutes. The result will be printed out within seconds of the completion of the testing. Since no feedback is necessary during the test, autorefractors are ideal when dealing with children or those with disabilities.

The topical map (topography) attained at the same time will then be transferred to the computer for analysis and color printout. Topography is used by Dr. Najafi-Tagol for several distinct purposes: either to diagnosis corneal disease; or to form a preliminary plan in LASIK surgery; or as adjunctive information in the selection of the intraocular lens to be placed during cataract surgery. Eye Institute of Marin is the center of Excellence in Eye Care. That goal requires the use of state-of-the-art technology to provide the most accurate and complete results for Dr. Najafi-Tagol’s decision-making process.

Keratometer

A keratometer is used to measure the curvature of the cornea. Similar to a digital camera, the device photographs your cornea and creates a mathematical measurement of the curvature of the surface of the eye.

Dr. Najafi-Tagol uses these measurements to assess the proper curve of the cornea to ensure the best possible fit of your contact lenses.

Optical Coherence Tomography (OCT)

This cutting-edge technology can be compared to a CT scan, but uses lightwaves instead of soundwaves to provide high resolution images of the internal structures of the eye. Used in both detection of disease and evaluation of the efficacy of treatment therapies, OCT has been established as useful in Macular Degeneration, Glaucoma, Diabetic Retinopathy, and other disorders of the macula, retina, and optic nerve.

In disorders and degeneration of the macula, OCT images can show thinning or thickening of macular tissues, including the development of a hole in the macula or the accumulation of abnormal fluid under the macula.

Visual Field Analysis, as mentioned above, is considered the standard-of-the-industry for early detection and follow-up of Glaucoma. Here at Eye Institute of Marin, we take that a step further with OCT tests specific to glaucoma - Optic Nerve (ON) and Retinal Nerve Fiber Layer (RNFL) scans. Studies support the idea that the earliest detection of glaucoma is found in changes to the RNFL. The OCT creates a graph of the patient’s current tissue thickness over age- and demographically-matched comparison data against which Dr. Najafi-Tagol may evaluate the findings. Over time, repeating the ON scans could indicate relative stability or, conversely, progression of the damage to the optic nerve caused by glaucoma. The OCT provides quantative, 3-dimensional information of the optic nerve which formerly was not available to physicians.

OCT testing is easy on the patient, non-invasive, and usually requires dilation.