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Visudyne™ (Verteporfin) Therapy Visudyne Therapy: A Two-Step Process Step 1 IV administration of a non-toxic, light activated drug Step 2 Subsequent activation by a specific wavelength of light using nonthermal diode laser device Visudyne Formulation Visudyne is a lightactivated drug: Supplied in single-use 15 mg vials Sterile, lipid-based, freeze-dried, dark-green powder Stored at room temperature (20–25ºC or 68–77ºF) Establishing the IV Line A free-flowing IV line is established, preferably in the antecubital vein Determining GLD and Treatment Spot Size Determine GLD of entire Treatment spot size GLD lesion on photographic image Calculate actual GLD on retina Add 1000 µm to allow a 500 µm border around lesion (Ensure full coverage of lesion and allow for small eye movements) Copyright protected Treatment spot should be no closer than 200 µm to edge of optic disc Setting the Laser Zeiss Visulas 690s Laser and Visulink PDT adapter Coherent Opal Photoactivator Laser and LaserLink adapter Enter contact lens magnification Enter the spot size (GLD + 1000 µm) Start the timer at the beginning of infusion Visudyne Infusion Kit Tubing Filters Needles Catheter Syringes Calculating BSA Height Weight BSA (e.g.: 1.88 m2) Visudyne Reconstitution Visudyne is reconstituted with sterile water for injection 7 mL of water is added to the vial to give a volume of 7.5 mL The vial is gently agitated to ensure complete dissolution Solution must be protected from light and used within 4 hours Reconstituted drug has a concentration of 2 mg/mL Calculating the Visudyne Dose Drug dose 6 mg/m2 Total drug dose e.g. 11.28 mg BSA e.g. 1.88 m2 Reconstituted drug concentration 2 mg/mL = Volume reconstituted drug e.g. 5.64 mL Preparing the Infusion The appropriate volume of Visudyne solution is withdrawn from the vial The Visudyne solution is transferred to the 30 mL syringe D5W is added to give the final 30 mL volume for infusion Infusion Connections Syringe in pump A 1.2 µm filter is fitted to the syringe The syringe is connected to the IV line Infusion tubing Filter Needle Venous access Infusing the Visudyne Solution An infusion or syringe pump delivers the 30 mL of drug over 10 minutes The timer on the laser system is started at the same time as the infusion Physician or nurse must monitor patient throughout 10-minute infusion Precautions to Avoid Extravasation Extravasation may cause severe pain, inflammation, swelling, and discoloration of the injection site The IV line should be carefully monitored during treatment and infusion stopped if extravasation is suspected or recognized Even with good technique, extravasation may occur Procedure in the Event of Extravasation If more than half the dose delivered Proceed with light application, as scheduled (15 minute after start of infusion, even if duration of infusion was less than 10 minutes) If less than half the dose delivered Obtain better venous access Begin light application 15 minutes after restarting infusion Apply cold compress or ice immediately Elevate patient’s arm for 1 day, when possible Protect from light for at least 5 days or as long as skin is swollen or discolored Consult burns specialist or dermatologist if needed If venous access was not obtained after several attempts, treatment can be attempted again after 24 hours Ending the Infusion The pump is turned off The IV line is flushed with 5 mL D5W until all remaining Visudyne is cleared from the line The laser timer will indicate when to begin light application Positioning Patient and Applying Laser Patient is positioned at slit lamp immediately after end of infusion Light source: Non thermal diode laser Light is applied 15 minutes after start of infusion Light at 689 nm is delivered via a fiber optic and slit lamp using a contact lens Light dose – 600 mW/cm2 – 83 seconds 50 J/cm2 Visudyne: Light application Why 689 nm (red light) ??? Light at this wavelength is not absorbed strongly by naturally present substances The strongest absorption peak is at 400 nm (blue light) Not clinically useful, as this is the same as the absorption peak of oxyhaemoglobin Concurrent Bilateral Treatment If the patient has received previous Visudyne treatment with an acceptable safety profile: The first eye (with aggressive lesion) is treated 15 minutes after the start of infusion Immediately after treatment of the first eye, the laser is reset to the parameters of the second eye, with the same light dose, intensity and duration The second eye is treated no later than 20 minutes after the start of infusion Follow-up and Retreatment Copyright protected Early phase of angiogram showing recurrent leakage within a hypofluorescent region 3 months after Visudyne therapy Follow-up visits after a treatment should be scheduled at least as often as every 10–14 weeks Fluorescein angiography is required to determine whether leakage has recurred Retreatment is often necessary during the first 2 years Patient Education Physician needs to manage patient expectations In patients for whom treatment is indicated, Visudyne therapy: – Reduces risk of moderate or severe vision loss in AMD – Increases likelihood of stable or improved vision in pathologic myopia Retreatment often required at 3-month intervals in first 2 years Patient Education Patients should be provided with information to take home Patients should avoid exposure to direct sunlight or strong artificial light (halogen) according to physician’s instructions (Up to 48 hours after t/t) e.g. dental procedure, surgical operating rooms Normal indoor / home light – tube light, bulb light, television light - Patient Education Patients should wear dark sunglasses, long sleeves and trousers, if they need to go outdoors during the first 48 hours (sunscreens do not protect from photosensitivity reactions) Patients should call with questions, concerns or problems (e.g. sudden decrease in vision, pain at injection site) Low Vision Aids CNV rarely causes total blindness Low vision aids may help many patients to perform daily activities Management of Clinically Relevant Adverse Events Extravasation Infusion-related back pain No adverse sequelae known at this time Resolves within a short time Photosensitivity reactions Avoidable with proper precautions Avoidable with proper precautions Treat as sunburn (sunscreen is ineffective) Acute severe vision decrease within 7 days Observation, no retreatment recommended