PASCAL
®
Synthesis TwinStar Ophthalmic Scanning Laser Systems
Page 29 of 142
88293-EN, Rev C
Contraindications
The following conditions are contraindications for performing laser trabeculoplasty:
•
Any corneal opacities, cataract formation and vitreous hemorrhage which can
interfere with the laser surgeon’s view of the target structures
•
Aphakic eye with vitreous in the anterior chamber
•
Neovascular glaucoma
•
Glaucoma caused by congenital abnormalities of the angle
•
Less than 90º of open angle or extensive low-lying peripheral anterior synechiae
present circumferentially around the angle
•
Significant corneal edema or a diminished aqueous clarity obscuring visualization
of the angle detail
•
Glaucoma secondary to active uveitis
Tissue absorption is directly dependent upon presence of pigmentation; therefore, dark
pigmented eyes will require lower energies to obtain equivalent results as compared to
light pigmented eyes. Do not treat albino patients that have no pigmentation.
For patients with wide variations in retinal pigmentation as evaluated by ophthalmoscopic
observation, select multi-spot patterns which cover a homogeneously pigmented smaller
area to avoid unpredictable tissue damage.
Exercise caution while setting treatment parameters (for example exposure time and the
number of spots per pattern) when laser burns are to be delivered in the non-macular area
for long time periods leading to longer grid completion times. Please be aware that with
longer completion times, the possibility of patient movement increases the risk of
treatment of unintended targets.
In addition, following are the contraindications for photocoagulation treatment:
•
Patient cannot fixate their eye or hold still (for example patient has nystagmus).
•
There is inadequate view of the fundus due to opacity (not clear media so
physician cannot see the fundus).
•
Presence of sub retinal fluid in the patient’s eye.
Potential Complications or Side Effects
Potential complications specific to retinal photocoagulation include inadvertent foveal
burns, choroidal neovascularization, paracentral scotomata, subretinal fibrosis,
photocoagulation scar expansion, Bruch’s membrane rupture, choroidal detachment,
exudative retinal detachment, pupillary abnormalities from damage to the ciliary nerves,
and optic neuritis from treatment directly or adjacent to the disc.
Potential complications specific to laser iridotomy include iritis, visual symptoms, and
rarely, retinal detachment.
