Medmont Studio. A Platform for the Digital Environment.

Laurence O’Connell Dip. Opt.

Craig Andrew S.L.A. Engineer.

Background.

The digital age has arrived for the eyecare professions in the form of computerisation of testing and recording systems. However, incompatibility of apparatus from various manufacturers has meant time consuming and expensive duplication of resources for practitioners until now. Medmont’s Studio software is a platform that will support and incorporate into one database digital information from a range of equipment.

Introduction.

OCA Optical Technology is producing, in conjunction with Medmont, an atlas of visual fields for users of M600/700 automated perimeters. The principals are a computer engineer/software designer, and an optometrist with an extensive database of visual fields gathered over many years in a practice isolated from major medical facilities but with a regularly visiting ophthalmologist. The atlas will be published in a digital, interactive format on cd-rom, and in order to illustrate case studies in a meaningful manner, images will be presented from a variety of clinical resources. Studio version 3.3.1 is now available commercially.

Equipment.

All equipment is networked with central data storage in a server and backup. See left(click to enlarge).

Medmont M600/700.

Medmont’s regular upgrades of M600/700 technology and reasonable cost structures are the reason this is now the gold standard in Australasia and many other parts of the world for automated field analysis. For optometry, it serves not only as a device to monitor existing pathology but also as a primary diagnostic tool for investigation of unexplained visual deficit or unusual symptoms. Ophthalmology, with access to a wider range of investigative tools still tends to use fields for simple and non-invasive monitoring of known disease. Both roles are better served in the Studio 3.1.1 modality, with its new algorithms reducing testing time significantly. The format initially looks unfamiliar, but is intuitive and user friendly so that “conversion time” is minimal. The results in the new format tend toward the conservative, so that a point may in fact be a decibel or two depressed compared with the later stand alone windows versions. Field profiles in all other ways look very similar. The three dimensional representations, the comparison mode and the ability to customise results are outstanding. (The ability to present results in monochrome and humphrey-type formats is either a nice way to introduce tardy technologists to the new millennium or a subtle Australian joke….) Particular mention must be made of the new flicker test. Researchers have long been aware that damage to ganglion cells is effected very early in ocular disease processes, and this is detectable using flicker techniques, due to the impaired transmission of nerve impulses, before manifest field defects are apparent. Medmont have refined this function in studio 3.1.1 and it is an excellent clinical tool, especially useful in discriminating the ocular hypertensives from the true glaucomas at a point in the disease process prior to damage occurring at the optic nerve. The instruction to the patient should include the message to only respond to lights that twinkle. Another very useful, non-standard feature OCA optical technology has added is the ability to monitor and control the M600 from remote locations. At this stage this is within the network but could be anywhere.

Medmont E300 Videokeratoscope.

The E 300 videokeratoscope/topgrapher has proved to be a valuable addition to the clinical armoury for monitoring corneal health. In particular, the popularity of corneal surgery makes a topographer an essential tool, but it has obvious application in contact lens practise and recording progress of anterior eye pathology. The software package enables the same data manipulation and comparison processes as with the perimeter.

Ease of use is outstanding, and accuracy is excellent. Tests by Tang et al of QUT confirmed its precision.

Medmont DV2000 for Biomicroscopic digital imaging.

Medmont’s DV2000 software enables the importation, storage and manipulation of images from any video/still capable slitlamp. We have used a simple camera with moderate resolution, adequate for anterior pictures but inadequate for gonioscopic detail. An upgrade to a digital camera in the short term will alleviate this problem.

Medmont DV2000 for Retinal Camera digital imaging.

A (mydriatic) fundus camera, Sony DXC-950 P 3 CCD colour video camera plus mount, camera adaptor CMA-D2 driven by a HP XM600 pentium III Kayak computer and Medmont DV2000 software form the digital retinal camera system. Quality images are obtained and the image processing options are excellent. Temporal comparison of ocular conditions, seeing the retinal image immediately on screen and the ability to show the patient their own fundus are the major benefits at present. In future, using commercially available software such as netmeeting, distance diagnosis and treatment options are envisaged.

Discussion.

It is our opinion that Medmont have made a quantum leap and surpass any other digital technology on the market. Studio 3.3.1 and its hardware components have raised the bar in patient diagnosis and management.

Acknowledgements.

Kevin and Tim Way of Ophthalmic Instrument Company, New Zealand supplied the fundus camera at extraordinary mate’s rates. Malcolm Jameson and the team at Medmont, Australia, have provided the Studio software for beta testing and have been a source of ideas and inspiration not only during the establishment phase but also in production of the atlas. Professor Tony Molteno and consultant ophthalmologist David Peart, Eye Dept. Dunedin hospital, for their ongoing support.

References.

1. Rota-Bartelink, A. The diagnostic value of automated flicker perimetry. Current Opinion in Ophthalmology, 1999, 10:135-139.
2. Zhang L, Drance S, Douglas G, The Ability of Medmont M600 automated perimetry to detect threats to fixation. J. Glaucoma 1997, vol6, #4, 259-262.
3. Rota-Bartelink A, Pitt A, Story I, Rait J. Automated flicker perimetry in early primary open angle glaucoma. Australian and New Zealand Journal of Ophthalmology Supplement 1996; 24(2) 25-27
4. Mc Kendrick A, Badcock D, Heywood J, Vingrys A. Effect of migraine on visual function. Australian and New Zealand Journal of Ophthalmology (1998) 26 (Suppl.) 113-115.
5. Vingrys A, Pesudovs K. Localised scotomata detected with temporal modulation perimetry in central serous chorioretinopathy. Australia and New Zealand Journal of Ophthalmology (1999) 27, 109-116
6. Phipps J, Guymer R, Vingrys A. Temporal sensitivity deficits in patients with high-risk drusen. Australian and New Zealand Journal of Ophthalmology (1999) 27,265-267.
7. Siu A, Chung P, Ng B, Koo C, Chu G. Factors affecting flicker perimetry. Clinical and Experimental Optometry 80.6 November-December 1997 218-224.
8. Tang W, Collins M, Carney L, Davis B. The accuracy and precision performance of four videokeratoscopes in measuring test surfaces. 8^th Scientific meeting in optometry, Sydney July 1999.

Images.

Figure 1 : E 300 map of cornea pre and post lasik surgery. The right picture illustrates the difference between the two.

Figure 2 : From Studio 3.1.1. Retinal photo of treated choroidal melanoma and associated field defect represented in three dimensions. Note radiation retinopathy at macula.