Article

SPOTLIGHT ON TECHNOLOGY & TECHNIQUE

Couple up for a better diagnostic device

MOVU SS-OCT biometer plus Alcon Vision Planner = the ARGOS, a power combo for preop testing.

Horse buggies and engines. Toasters and ovens. Smartphones and just about anything else you can think of. History is full of examples of technologies that have been combined to produce one, all-encompassing tool to make life and work faster, easier and more convenient.

Add ARGOS to the list, which now combines MOVU’s swept source-OCT (SS-OCT) biometer with Alcon’s image-guidance and vision planning software into an all-in-one device for cataract preoperative testing.

HOW IT WORKS

ARGOS gathers the required diagnostic measurements and captures a high-resolution image of each patient’s eyes. The data and images are then used for presurgical planning and to provide intraoperative guidance and postoperative assessment, reducing potential sources of transcription errors.

By merging the two devices, ARGOS also improves examination efficiency and eliminates the need for multiple devices in the surgical suite, says Lawrence Woodard, MD, medical director of Omni Eye Services in Atlanta. “The first advantage to this combination is that it decreases patient maneuvering by eliminating one machine from this process,” says Dr. Woodard, a consultant, speaker and clinical investigator for Alcon. Because the ARGOS biometer also serves as a reference unit for image guidance, “the patient no longer has to get measurements on two different devices.”

ARGOS transfers patient data to the LenSx (Alcon) digital marker, microscope digital marker and ORA. This decreases opportunities for human transcription errors while also significantly diminishing the time required for technician data entry and measurement capture speed, which the company says is less than 1 second.

BETTER MEASUREMENTS, BETTER OUTCOMES

The inclusion of the Alcon vision planning software permits easy preoperative IOL selection and management of astigmatism treatment options by staff based on the surgeon’s programmed nomograms, Dr. Woodard says. “It has a very intuitive program to enable optimization for each IOL based on postoperative refractive data, thereby helping to improve surgical outcomes,” he says. “My technicians love it.”

Another significant feature of Argos is its ability “to acquire axial length measurements in all types of lenses, even the most mature, white or brunescent cataracts,” Dr. Woodard says. “The need for manual scans is almost completely eliminated, so there’s additional time saved and less patient manipulation during the preoperative testing process. This also improves outcomes because axial length measurements with manual scans are so variable and operator dependent, resulting in a greater likelihood of postoperative refractive surprises.”

The success with acquiring axial length measurements in very dense or mature cataracts is partly due to the Enhanced Retinal Visibility (ERV) mode, which improves the device’s ability to detect the surface of the retina by increasing sensitivity by 10X compared to standard mode.

DO YOU REALLY NEED TWO DEVICES?

In a head-to-head comparison of dense cataract cases (≥grade IV cataract patients), ARGOS boasted acquisition success rates that were 41% higher than those of a leading biometer, and acquisition failure rates 72% lower, thereby reducing the need for ultrasound biometry.1 The acquisition rates were determined by a large, retrospective, single-center study of 622 eyes of 622 Japanese patients who underwent presurgical biometry with Argos and two other biometers.1

“These studies mirror what we’ve seen with our patients,” Dr. Woodard says. “Our technicians feel confident in the [ARGOS] measurements and don’t waste time using manual scans.”

Mean measurements of anterior corneal radius curvature with ARGOS also demonstrated excellent correlation with IOLMaster 5002 and 7003 as well as Lenstar (Haag-Streit USA).2 Axial length measurements with ARGOS demonstrated agreement and good correlation with IOLMaster and Lenstar.1,2-8

“When we began using Argos, it was very important that we continue to obtain keratometry and axial length measurements that were consistent with the above devices that we had been using over the years,” Dr. Woodard says. “It can be very unsettling to add a new instrument to the process, due to fear of worsening postoperative outcomes. However, we noticed that Argos measurements were quite consistent with these devices, so our fears were quickly put to rest.”

Under the companies’ strategic alliance, MOVU will continue to manufacture ARGOS, and Alcon will be the exclusive distributor, marketer and service provider. Argos is being rolled out in a limited capacity in the United States. Owing to cancelations of large group meetings being imposed due to the COVID-19 crisis, ARGOS was scheduled to launch at the virtual ASCRS meeting on May 16-17 at press time. OM

REFERENCES

  1. Tamaoki A, Kojima T, Hasegawa A, et al. Clinical evaluation of a new swept-source optical coherence biometer that uses individual refractive indices to measure axial length in cataract patients. Ophthalmic Res. 2019;62:11-23.
  2. Shammas HJ, Ortiz S, Shammas MC, Kim SH, Chong C. Biometry measurements using a new large-coherence-length swept-source optical coherence tomographer. J Cataract Refract Surg. 2016;42:50-61.
  3. Omoto, MK, Torii H, Masui, S. et al. Ocular biometry and refractive outcomes using two swept-source optical coherence tomography-based biometers with segmental or equivalent refractive indices. Sci Rep. 201; 6557. https://doi.org/10.1038/s41598-019-42968-3 .
  4. Higashiyama T, Mori H, Nakajima F, Ohji M. Comparison of a new biometer using swept-source optical coherence tomography and a conventional biometer using partial coherence interferometry. PLoS ONE. 2018;13: e0196401.
  5. Whang WJ, Yoo YS, Kang MJ, Joo CK. Predictive accuracy of partial coherence interferometry and swept-source optical coherence tomography for intraocular lens power calculation. Sci Rep. 2018;8:13732.
  6. Hussaindeen JR, Mariam EG, Arunachalam S, et al. Comparison of axial length using a new swept-source optical coherence tomography-based biometer - ARGOS with partial coherence interferometry-based biometer-IOLMaster among school children. PLoS ONE 13:e0209356.
  7. An Y, Kang EK, Kim H, et al. Accuracy of swept-source optical coherence tomography-based biometry for intraocular lens power calculation: a retrospective cross-sectional study. BMC Ophthalmol. 2019;19:30.
  8. Huang J, Chen H, Li Y, et al. Comprehensive comparison of axial length measurement with three swept-source OCT-based biometers and partial coherence interferometry. J Refract Surg. 2019;35:115-120.