Transpupillary thermotherapy (TTT) is a technique that uses a modified diode laser to deliver low heat through the pupil to the eye's posterior.
It is used to treat ophthalmologic conditions such as choroidal melanoma, retinoblastoma, and classic and occult choroidal neovascularization. However, it may not be suitable for instances where the malignant tumor's margin is close to the optic nerve.
Retinoblastoma is a common intraocular tumor that typically affects children below five years of age. Late diagnosis of the condition could result in death. On the other hand, choroidal melanoma is common in adults. It refers to cancer that develops in the choroid
Choroidal neovascularization (CNV) is a common cause of adult-oriented blindness. It is mostly associated with age-related macular degeneration (AMD), a deterioration of the retina's central position.
TTT can work on its own or with a combination of radiotherapy or chemotherapy if tumors are large. It is considered a better alternative to the laser technique used in standard photocoagulation therapy since it uses a lower power laser for more extended periods. Damage to surrounding tissue is therefore minimized.
Also Known As
Before the Procedure
The patient may not require special preparations since surgery is usually an outpatient procedure. It is vital to have an appointment with the doctor before surgery to understand what the process entails. The doctor should provide enough information concerning the treatment to facilitate decision making among patients.
It may be necessary to notify the doctor about any allergies or present medical conditions. The information should enable the doctor to select a suitable treatment option for the patient. One may proceed with whichever medication they are under unless the ophthalmologist advises otherwise.
Patients should make arrangements on how to get home after the procedure since they may not be able to drive.
The procedure usually takes place in an eye hospital with the session lasting no longer than twenty minutes. The first step to the process is eye measurement. The doctor then gently cleans the eye area before administering eye drops to widen the pupil.
After dilating the pupil, the patient receives drops of local anesthesia to numb the eye. Therefore, the patient will be awake throughout the session but will experience no pain.
In retinoblastoma, the child may receive general anesthesia, and so will be unconscious throughout the surgery.
The patient then sits on a slit lamp, and the doctor focuses a laser into the eye at intervals of one minute. The infrared diode laser passes through the pupil to get to the tumor at the eye's posterior.
Risk & Complications
The likely risks associated with the process are:
- Eye scarring
- Shrinking of the iris
- Burns or damage to the retina
- Clouding of the eye lens
- Swelling of the eye or the eyelid
The laser light may harm healthy tissue and, as a result, adversely affect vision. Besides that, there may be regrowth of the tumor since some cancer cells can stand treatment.
Aftercare and Recovery
After treatment, the eyes may become sensitive. Therefore, it is crucial to protect them from further risks and complications. Some aftercare routines may include:
- Avoiding eye exposure to irritants such as soap, smoke, and makeup. The irritants can cause the sensation to rub the eyes, which would result in more harm. Patients may receive eye shields for use, especially at night, to help prevent constant eye touching.
- Engaging in less exhausting physical activities to prevent straining the eye muscles. It is also essential to have enough rest to give the eye a chance to heal.
- Limiting eye exposure to gadgets such as mobile phones and computers and the use of dark glasses when outside.
- Follow up visits to the hospital for check-ups. The doctor should notify one of the next sessions.
Patients should also seek immediate medical attention in case of worsened pain, severe swelling, excessively red eyes, and vision loss. Recovery among patients should be in a couple of days.
TTT works to control tumors. When TTT is used after radiotherapy or chemotherapy, it may provide the best results and reduce the possibility of enucleation.