Cyclocryotherapy is a technique that uses low temperatures to destroy the fluid producing part  of the eye. An increase in fluid production elevates intraocular pressure which highly contributes to glaucoma. Glaucoma describes eye conditions characterized by damage to the second cranial nerve.

Symptoms are not immediately noticeable since the condition does not affect the central vision at first. As the cranial nerve damage progresses, patients usually report reduced visual acuity. In severe cases, vision loss may occur. The main contributing factors to glaucoma are old age and genetic inheritance.

Cyclocryotherapy came into existence in 1950. Bietti developed this technique intending to control intraocular pressure. The method remained unpopular until De Roeth reported a high success rate in using the process to reduce intraocular pressure in adult patients. Since then, it has gained popularity in the medical field but is mainly reserved for instances where other options were unsuccessful or unavailable.

Cyclocryotherapy works by controlling glaucoma through lowering the amount of aqueous humor produced in the eye. In addition, it helps to minimize pain felt by patients with severe glaucoma.

Also Known As

  • Cyclocryopexy


Before the Procedure

The procedure, as with other forms of surgery, has its risks and benefits. It would be essential to have a brief session with the doctor to learn about the advantages and disadvantages of the process. It is only after the patient's consent that the ophthalmologist should proceed with the operation.

It is necessary to notify the doctor about any allergic reactions and other medical conditions. For patients under glaucoma medication, there may be no need to stop the medication anytime before surgery.

The procedure, in most instances, does not require admission in the hospital. Therefore, patients usually go home on the same day. The eye may swell after the operation, thus the need for the patient to have someone drive them home.


The procedure involves the following steps:

  • The doctor will first administer anesthesia to numb the patient's eye. In case of anxiety, s/he may administer general anesthesia.
  • Using lighted equipment, the doctor locates the ciliary body.
  • Under minimal pressure and in a clockwise direction, the surgeon directs a cryoprobe for approximately one minute to the sclera.
  • The probe is directed to the eye several times while avoiding the area where extraocular muscles grip the eye.
  • For first time treatments, the doctor treats a half part of the eye. Where the response to surgery is good, or glaucoma is not severe, the doctor treats a quarter of the eye.
  • After completing the procedure, the patient will receive a steroid injection that will help to reduce inflammation. The doctor will also apply an ointment to ensure the eye remains dilated.


Risks & Complications

Cyclocryotherapy can be a risky procedure; therefore, patients with potentially good vision should avoid it. One should also avoid it if they have undergone a cataract surgery that resulted in a lens implant.

The common risk with cyclocryotherapy is phthisis bulbi. It refers to an eye problem where aqueous humor production drops to a critically low level. Other associated risks may include swelling, the formation of cataracts, detached retina, and inflammation. Patients with diabetes may be at a higher risk of experiencing inflammation.

Numbing the eye and associated muscles may result in droopy eyelids. The eyes may also become sensitive to light after the procedure. Another side effect may be pain and discomfort that begin soon after the practical impact of anesthesia fades.

Patients with intact lenses who undergo this procedure are more prone to experiencing difficulties after surgery. One main complication is complete loss of vision that may arise from the procedure's risks

Aftercare & Recovery

After surgery, the doctor may advise the patient to implement some or all of the following routines:

  • Continuation of glaucoma medication since there may be a possibility of increased intraocular pressure after surgery. However, some medications such as miotics, should be avoided.
  • Use of steroids to minimize inflammation and atropine to reduce post-surgery discomfort.
  • Use of acetaminophen to ease the pain after surgery.
  • Avoiding exhausting physical activities or activities that strain the eye.
  • Wearing sunglasses while out in the sun.
  • Avoiding eye rubbing and constantly touching it.
  • Follow up hospital visits after surgery. The visit would be dependent on the doctor's appointment.

The eye may heal in approximately one to two months, and during this time one may be able to determine the effectiveness of the surgery.


The outcome of a cyclocryopexy is decreased intraocular pressure and pain. The success rate of the procedure increases with repeated surgeries. In children, the success of cyclocryotherapy is low since the fluid producing part of the eye is very resistant to cold treatment. As a result, the procedure is commonly repeated.