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s FUNDAMENTALS IN FIVE FIXING Laser vitreolysis is an effective and minimally invasive treatment option for these visual disturbances.

BY MOHAMMAD IDREES, FRCS(Edin)

n 2005, while working in Pakistan, I met a patient with posterior capsule opacification who com- “THE JOURNEY THAT STARTED WITH A plained of hazy vision years after /IOL surgery. I performed SINGLE CASE HAS CONTINUED, AND I NOW INd:YAG laser capsulotomy, and the patient experienced immediate improvement in visual function. A WISH TO SHARE MY EXPERIENCE.” week later, however, he returned and said that, while I’d solved one problem problem was resolved in just one ses- It is also best to avoid patients with for him, I’d created another: He was sion. I repeated the treatment 3 weeks multifocal IOLs or with any media now experiencing floaters that later, and both the patient and I were opacity, uncontrolled glaucoma, were causing difficulty in driving. satisfied with the results. active anterior or posterior segment At first, I didn’t know how to help The journey that started with a inflammation, active or healed retinal him, but I started to consider the single case has continued, and I now necrosis, untreated possibility of using laser vitreolysis to wish to share my experience with this predisposing to degeneration, or active eliminate the fragments of posterior high-reward and low-risk technique. cystoid macula edema. lens capsule in the anterior vitreous. In this procedure, a 3-ns laser pulse is FUNDAMENTAL CHOOSING THE BEST FUNDAMENTAL PREPARE FOR THE focused on an 8-μm spot on the float- CANDIDATES IS THE PROCEDURE er. The laser causes optical breakdown 1 KEY TO OVERALL 2 Dilate the pupil. of the vitreous opacity into plasma, SUCCESS Laser vitreolysis requires a fully dilated which appears as a gas bubble and is The success of any procedure is pupil. I usually instill one drop of 2.5% absorbed in 10 to 30 minutes. measured by patient satisfaction. For phenylephrine followed by a drop of My patient agreed to give it a the best results, the surgeon must 1% tropicamide 5 minutes later, and try, and, to my surprise, 70% of his know which patients are most likely I advise the patient to sit in the wait- to benefit from laser vitreolysis and set ing room with gently closed eyelids. realistic expectations for those patients. The pupil usually fully dilates in about One must consider the limits of his or 20 to 30 minutes. her surgical skill and expertise, as well Position the patient. The patient as the available laser technology. must be able to sit comfortably to A patient with a vitreous opacity undergo this procedure, as it is a high- such as a Weiss ring (Figure 1), onto tech, professionally demanding proce-

Courtesy of Karl Brasse, MD, MRCOphth which you can sharply focus the laser dure in which complete cooperation beam, is an ideal candidate, provided is needed from the patient to avoid the optical media are clear. It is best to complications and an unsatisfactory ensure that the vitreous opacity is away outcome. Once the patient is about to from the and the posterior lens sit for the procedure, I instill a drop of capsule in phakic to avoid damage topical anesthetic. After 3 minutes, I Figure 1. Presence of a Weiss ring in the vitreous. to these important ocular structures. proceed to the next step.

64 CATARACT & REFRACTIVE SURGERY TODAY EUROPE | FEBRUARY 2018 FUNDAMENTALS IN FIVE s

Once you find the vitreous opacity, coordinate it with the chart that you made when you performed the initial evaluation. (See My Toolbox.) You may need to ask the patient to look in the required position of gaze, and in some cases you may need to use a contrast filter. Adjust the laser parameters. The laser power should be

Courtesy of Karl Brasse, MD, MRCOphth set according to the size, shape, location, and density of the vitreous opacity. I usually start with power of 2.5 to 5 mJ, depending upon the location and density of the opacity. It is better to start with a low power and work up according to the response of the opacity in terms of optical breakdown and vaporization. Adjust the slit-lamp parameters. Begin with minimal Figure 2. Do not shoot the laser if it is in line with macula, blood vessels, or the . magnification, as this allows scanning of a large area of the Apply the vitreolysis lens. Ensure that the lens is opti- vitreous. Increase the illumination gradually to the required cally clear, clean, and free from debris or dust. Use a dis- level. Once you locate the vitreous opacity that is causing persive, clear viscoelastic gel. Ensure that there are no air the floater, you can proceed to 8X magnification to exam- bubbles in the gel in the cup of the vitreolysis lens. Start ine the vitreous opacity and to plan where and with what filling the cup from the base to prevent air bubbles in the approach to apply the laser. If needed, you can increase to viscoelastic gel. Fill about half the cup to avoid spilling the 12X magnification. viscous solution onto the patient’s cheek during lens appli- Switch on the the laser, but keep it at minimum power. cation. Ask the patient to gently look up, retract his or her Increase the intensity of the laser aiming beam to the maxi- lower eyelid with your left index finger, and apply the vit- mum required and see if you can accurately and sharply focus reolysis lens with your right hand while asking the patient the beam on the vitreous opacity without any astigmatic to look straight ahead. Then gently release the eyelid and points in focusing. Use the laser offset as needed.

proceed to the next step. Courtesy of Karl Brasse, MD, MRCOphth Find the vitreous opacity. It is important to have a clear view of the vitreous opacity causing the floater and to achieve a sharp focus of the laser aiming beam on the vitre- ous opacity. Scan the vitreous with 8X magnification on the slit lamp. Gradually move from anterior to posterior, then from left to right, then from top to bottom. Rescan if needed.

MANAGE EXPECTATIONS Before you begin, ensure that the patient understands that the aim of the procedure is to achieve symptomatic relief and functional improvement Figure 3. Vitreous opacity before laser treatment. from the complaint of visually disturbing floaters. Set realistic expectations about the treatment and explain possible risks. Make the following points: • This is a minimally invasive and painless procedure that takes between 15 and 60 minutes. The patient will see the flash of the laser and hear sounds. • Patient cooperation is important to increasing success and minimizing risk of complications. The patient should not move his or her eye, head, face, or body during the laser treatment and must not squeeze the eyelids. • The patient may see dark specks due to gas bubbles for 15 to 30 minutes after the treatment. • Once a floater is treated, it will never come back, but new floaters can appear as part of the degeneration of the vitreous. Figure 4. No vitreous opacity and no floater after laser vitreolysis.

FEBRUARY 2018 | CATARACT & REFRACTIVE SURGERY TODAY EUROPE 65 - - - - - ) ) to evaluateto ) din WAIT ABOUT 4 WEEKS WAIT ABOUT 4 WEEKS BEFORE PLANNING BEFORE PLANNING TOUCHUPS OR REPEAT TREATMENT EVALUATE THE THE EVALUATE PATIENT AFTER THE THE PATIENT AFTER PROCEDURE My Toolbox My n 5 4 Special thanks to Karl Brasse, MD, Brasse, Karl to thanks Special After 2 days, I examine the patient,the examine I days, 2 After After treatment, I instill a topicala instill I treatment, After threeadvised are drops eye Antibiotic Consultant ophthalmologist, Aldara Hospital & Consultant ophthalmologist, Aldara Hospital & [email protected] Financial disclosure: None acknowledged Medical Center, Riyadh, Saudi Arabia   FUNDAMENTAL FUNDAMENTAL MOHAMMAD IDREES, FRCS(E n n n article,the of review his for MRCOphth, photographs. and advice, if the IOP is expected to rise. I suggestI rise. to expected is IOP the if days2 or 1 for analgesic oral an of use steroid Topical headache. for needed if atimes three advised are drops eye inflammationas days, 7 to 5 for day trauma,any of outcome natural a is deliverylaser of procedure the although invasive. minimally is vitreous the in float a perform acuity, visual check and IOP, monitor evaluation, erscope Iimprovement. symptomatic evaluate andsatisfaction visual of level the note ofquality in improvement functional detachment,retinal any for look I life. Iuveitis. or IOP, elevated opacity, lens plan before weeks 4 for wait usually treatmentrepeat or touchups ning needed. if antibiotic and lubricant eye dropseye lubricant and antibiotic a with sit to patient the instruct and room.waiting the in eye closed gently the from recover her or him helps This treat during light bright to exposure float the use I minutes, 30 After ment. (see erscope andbefore compare and floaters the mea I 4). and 3 (Figures treatment after hour. 1 after IOP document and sure thereif longer or days 3 for day a times contactthe to due abrasion corneal a is advisedare drops IOP-lowering lens. - - - - 2018 Communicate with the patient the with Communicate Figure 6. Volk Idress MidVitreous Lens. Figure 6. Volk Idress MidVitreous Lens. Figure 5. Idrees Floaterscope. Figure 5. Idrees Floaterscope. Don’t exhaust the patient or your single500 than more shoot not Do After shooting the laser, observe laser, the shooting After tired or the patient loses concentra loses patient the or tired cooperation. and tion self. what explain procedure, the during the what address and on, going is a After needed. if feeling, is patient shot next the before wait shot, laser vitre the on refocus can you so new a to settles it once opacity ous position. mJ1,000 exceed or shots laser pulse onein eye the in delivery energy of feelyou if treatment the Stop session. column to the right or left side of the of side left or right the to column the Focus system. viewing slit-lamp vitreous the on beam laser-aiming is focus sharp a once and, opacity laser. the shoot achieved, formation Plasma response: the rising bubble gas a like appear should location the in change with along up, opacity. vitreous the of density and laser the of absorption the Observe of evaporation successful and energy opacity. the vitreous opacity with coaxial illumina coaxial with opacity vitreous illumination the tilt case, this In tion. FEBRUARY

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- - - Direct laser The Idrees Floaterscope The Idrees Floaterscope PERFORM THE PERFORM THE PROCEDURE I use the Volk Idrees MidVitreous MidVitreous Idrees Volk use the I I use this chart to document information information document chart to use this I Sometimes it is not pos not is it Sometimes After locating the vitreous the locating After

. This laser technology must be optimized for must be optimized for . This laser technology 3 Use a side tilt and retroillumina It is important not to shoot the the shoot to not important is It Nd:YAG Vitreolysis lens. Idrees Floaterscope. Floater chart. FUNDAMENTAL you are focused on the floater with with floater the on focused are you precision. 100% tion laser-shooting technique when necessary. the at directly laser the shoot to sible is clearly focused on the vitreous vitreous the on focused clearly is error for margin no is there opacity; offset the and it, on focusing in proper with needed as used be must illumi slit-lamp the of positioning when laser the Shoot arm. nation vitreous opacities first.opacities vitreous the vessel, blood retinal a when laser the in is disc optic the or macula, of line the of background immediate 2). (Figure opacity the of treatment beam laser-aiming the that Ensure opacity, shoot the laser with a stable a with laser the shoot opacity, the of movement any without hand the of or head or eye, face, patient’s Treat system. laser-delivery slit-lamp opacities vitreous located anteriorly located superiorly treat Similarly, first. shooting. vitreous opacities and makes it easy to see, focus, and and focus, see, easy to and makes it vitreous opacities without wasting vitreous opacities shoot the laser at be lens must The vitreolysis misplaced laser energy. A Volk maintained in clean and scratchless condition. that the lens ensure clean it and LensPen can be used to smudges, or fingerprints. free from dust, grease, optics are safe use in the posterior segment. in the use safe no I have which I designed (but in which Lens (Figure 6), view of magnified a clear, financial interest). It provides (Figure 5) is used to assess the size, shape, density, density, the size, shape, assess (Figure 5) is used to settling and final of movement, location, direction floaters. position of from the Floaterscope. MY TOOLBOX CATARACT & REFRACTIVE SURGERY TODAY EUROPE

66 FUNDAMENTALS IN FIVE FUNDAMENTALS s