Of those with diagnosed DED, 86% also have MGD and 80% of those with rosacea also have MGD. Circa 2000, Toyos noted that when he used IPL to treat patients for rosacea, some reported improvents in their existing DED. IPL was, and still is, used to treat rosacea’s skin inflammations and telangiectasia. That realisation resulted in his development of IPL as a viable option in treating DED and MGD, as well as an association with the Lumenis company with which he has co-developed a number of clinical instruments.Toyos’ research has found that IPL coagulates oxyhaoglobin in situ, thereby reducing the calibre of the skin’s small blood vessels, resulting in an improvent in the appearance of the patient’s skin and a decrease in local inflammation. His early attpts to publish his findings in mainstream medical and ophthalmological journals resulted in accusations of him practising ‘voodoo’ medicine. It wasn’t until 2005 that he succeeded in being published. Generally, IPL stimulates glands including the meibomian, lacrimal, and thyroid glands.In 2003, Toyos and colleagues received a research grant from the ASCRS to study IPL in DED formally and their 2005 paper (Toyos, Buffa, and Youngerman) was the result. IPL joined other light treatments in medicine including: blue light for acne, IR for muscular treatments for sport and orthopaedics, red light for cosmetic enhancent, and IR used to stimulate retinal cells in AMD, the efficacy of which is wavelength-dependent.The Oculus Keratograph 5M instrument can confirm that IPL can restore meibomian glands that were considered ‘gone’ before treatment. IPL also decreases the microbiological population on the skin, might enhance the immunological syst, and alters the skin’s tone by altering its melanin content.The mainstream IPL devices use a xenon gas discharge tube, similar to those used in photographic electronic flashes, whose spectral ission characteristics can span the spectrum from 500–1,200 nm. The discharge time is in the order of milliseconds, the power, or fluence, ranges from 10–30 J/cm2, and filters can be interposed to rove unwanted wavelengths or to tailor the output to that desired.During exposure, the eye is shielded from direct exposure to the pulses of light, but the output head is still located as near as practicable to the lower lid margin. Skin tone is also a factor, as energy absorption is a factor and dark skins can become slightly depigmented. Melanin responds most to light between 300–800 nm, whereas oxyhaoglobin responds most to 700–1,000 nm.Toyos advised the use of ear-to-ear or full-face (above the jawline) exposure rather than a lids-only approach. Targeting the upper brow to expose the upper lid’s meibomian glands makes no difference to the outcomes achieved. A hand-held LED-based device for home use by the patient, offering just 2–3 J/cm2, was also detailed as a way of topping-up in-clinic treatment.The outputs of both the xenon discharge tube and, to a much lesser extent, the LEDs used in the home syst, decline with use and age. In the clinic instruments at least, that translates to a limited life over which adequate output can be sustained – even with the feedback loop incorporated in such instruments designed to guarantee that neither too much nor too little light is delivered by each pulse.The current device in use is the Lumenis M22, which Toyos donstrated throughout the ODMA17 weekend. A pulsed delivery is preferred because it allows the discharge tube to cool somewhat, helps patient relaxation, and results in reduced cell destruction. The foot of the delivery module is cooled so that it poses no threat to the skin it is in contact with during treatment.Four or more treatments are required when the meibum expressed from the meibomian glands has a toothpaste consistency. The first will result in a slight improvent in TBUT and by the fourth, a significant improvent can usually be realised. Generally, younger patients need fewer treatments, older more. IPL also kills Dodex sp. as well as resident bacteria.Photonic absorption by cell mitochondria at around 43°C results in increased protein synthesis and cell proliferation that produces tissue repair, enhanced pain control, and enhanced ATP synthesis. Research into the photomodulation of the inflammatory mediator IL-9 and chromosomal heat shock protein 70 (HSP70), increased by IPL, is ongoing and there is already some suggestion that cells can be protected against apoptosis and pathological changes.Improvents of up to 200% in TBUT with IPL were claimed, even when the baseline TBUT was short. However, even the improved TBUT was often found to be still abnormal. Patient satisfaction levels as high as 93% were aired. At the very least, an annual top-up was advised. Lighter skin requires more output to be applied because of its lower energy absorption.Although IPL lightens the skin, some sun exposure restores the skin to its original tone. Despite one article confirming the safe use of IPL in pregnancy, Toyos did not recommend such use in the absence of any data from a suitable clinical trial. Another caution he issued related to those on light-sensitising medications, suggesting that they be withheld while undergoing IPL treatment. No washout period before commencing was offered.Part 2 of the ODMA17 CPD report, summarising presentations from Professor Fiona Stapleton, Associate Professor Gerald Liew, and Professor Stephanie Watson, will appear in next month’s issue.More reading: ODMA CPD returns to Sydney
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