Carl Zeiss Meditec IOL Master
Cataract Surgery Arizona

IOLMaster - Quick Reference.

The space bar will take you to the next measurement mode.


IOLMaster database

Patient Database

  N key. IOLMaster Patient Database. This allows you to enter new patient data or review prior measurements from established patients. Depending on how the IOL Master software has been configured, this information may be stored anywhere from five to 100 days, after which time, the patient information will automatically be deleted in order to conserve space on the IOL Master hard drive.
IOLMaster broad view


  O key. IOLMaster Overview Mode. This allows for coarse (basic) image alignment prior to taking final measurements. In this mode, the patient is aligned with the IOLMaster by using the joystick. Tell the patient to look at the small yellow fixation light and then adjust the instrument-to-patient distance until the six light reflections on the cornea appear in focus. The small circle of lights and the cross hairs should be centered in the patient's pupil. This should be done prior to taking axial length measurements.
IOLMaster axial length

Axial Length Measurement

  A key or the pushbutton on the joystick. IOLMaster Axial Length Measurement or "ALM" mode. With the IOL Master, you can accurately determine the axial length of eyes ranging from 14.0 mm to 40.0 mm.

Ask the patient to look directly at the small red fixation light and then take all 20 measurements. Be sure to use the Best Measurement Technique and sample several areas within the measurement reticule until the best axial length display is obtained and continue to take measurements from that area. At least four of these measurements should be within 0.02 mm, and show an Ideal Axial Length Display. Delete those measurements that do not show an acceptable axial length display. It should be remembered that the quality of the axial length display is more important than the signal-to-noise ratio.
IOLMaster keratometry


  K key. This activates the automated IOLMaster Keratometry, or "KER", mode. The best measurements are obtained as follows: place a drop of artificial tears in each eye, have the patient blink several times, and then do all measurements with both eyes open as wide as possible. Remember to tell the patient to blink between each measurement. Take as many measurements as needed until good reproducibility has been established. Those measurements that show wide variability should be individually deleted. Typically, a set of good automated keratometry measurements will all be within 0.25 D in each meridian. When done properly, this feature of the IOL Master is highly accurate.
IOLMaster white-to-white


  W key. This activates the IOLMaster White-to-White, or "WTW" mode. This optional function is part of Software Option A. To measure the horizontal corneal diameter, align the IOLMaster and make sure that the iris structures, or the edge of the pupil, appear to be optimally focused. Confirm that the patient is able to see the fixation target and is looking straight at it. If the patient fails to fixate properly, the visual axis will be out of alignment, which may result in measurement errors.
IOLMaster optical acd

Anterior Chamber Depth

  D key. This activates the IOLMaster Anterior Chamber Depth, or "ACD", mode. Keratometry must be performed prior to the anterior chamber depth measurement. In this mode, the system will automatically activate the lateral slit illumination. To the patient, the lateral slit illumination will appear very bright and this should be mentioned prior to measuring the ACD. Throughout the anterior chamber depth measurement, the patient should continue looking straight ahead and directly at the small, yellow fixation light, not the bright illumination to the side.
IOLMaster iol calculations

IOL Calculation

  I key. This activates the IOL Calculation mode. Intraocular lens power calculations can be made using five different formulas after obtaining the necessary measurements (AL, ACD and Ks) from one eye, or both. Before the system calculates IOL options, you must enter the desired lens type(s) into the IOL database.
IOLMaster printer


  P key. This allows you to send a summary of the measurement information From IOLMaster to Printer. This summary includes a listing of all 20 axial length measurements, a graphic representation of the axial length display with the highest signal-to-noise ratio, the three selected keratometry values, all of the ACD measurements, and three WTW values with a graphic representation of the iris, visual axis and optical axis (if software option A has been installed). If you would like to print an individual axial length display, simply select the axial length display you would like to print using the cursor and then press the printing shortcut keys (CTRL + P). You may also print the screen from the white-to-white mode, by pressing the printing shortcut keys (CTRL + P).
IOLMaster data to pc

Export Data
to PC

  S key. Export Data from IOL Master to PC connected office management systems or to another computer. It requires a connection via the serial port. Before the export of data, select the export mode appropriate for the connected office management system via Options > Setup >Program Settings.
IOLMaster export to disk

Export Data
to Disk

  X key. Export IOLMaster Patient Measurement Data to Disk. Data is made available in a text file (IOLMexport.csv) for archiving and data analysis.
IOLMaster shut down

Shut Down

  E key. Exit IOL Master Software. In case of problems, turn off the power switch and disconnect the power cable!