LUMENIS Novus Spectra, Руководство оператора

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Anterior Segment Laser Procedures 91
Novus Spectra
0642-543-01, Rev A, 12/02
power should be reduced to avoid endothelial corneal burns. This
reduction of power may require additional applications of laser
energy in order to penetrate the iris.
• Contraindications to laser iridectomy include a flat anterior
chamber, a completely sealed angle, and angle-closure glaucoma
due to primary synechial closure of the angle. This may occur in
uveitis, neovascular glaucoma, or the iridocorneal-endothelial
syndrome. In these cases, pupillary block is not a contributing
mechanism.
Warnings
WARNING - Intraocular pressure should be closely monitored following
laser iridotomy or trabeculoplasty.
WARNING - Hemorrhage from the trabecular meshwork occasionally occurs
and is manifested as an ooze of blood from Schlemm's canal to the site of laser
impact. This is easily stopped by increasing the pressure of the gonioprism to
the cornea, or by applying a 200 µm spot size, low power coagulation at the
bleeding site.
WARNING - Pupillary distortion may be encountered if the iris root or
peripheral iris has been treated. This distortion may or may not be permanent,
depending on the severity of the accidental damage.
WARNING - Angle-closure glaucoma has been reported following laser
trabeculoplasty when miotics were discontinued. Medical therapy should be
continued following laser trabeculoplasty.
1
Precautions
CAUTION - Intraocular pressure elevations have been reported to occur in
up to 53% of eyes when 360° of the trabecular meshwork has been treated
with 100 spots at the initial session. Intraocular pressure rises occur most
frequently from 1 to 2 hours following laser treatment, although they may
occur several hours afterward.
2
For this reason, it is imperative to monitor
patients with severe damage, particularly when visual field loss involves fixation,
and it is not unreasonable to admit such patients for 24-hour monitoring of
intraocular pressure following laser trabeculoplasty.
CAUTION - Peripheral anterior synechiae may occur when the posterior
portion of the trabecular meshwork or other structures posterior to the
meshwork are treated. These are best avoided by meticulous delivery of a well-
focused laser beam.
CAUTION - Transient comeal epithelial bums have reportedly resolved
within 1 week without scarring. Endothelial bums are rarely encountered when
careful focusing is employed.
1. Reference 11, “Ophthalmology References”
2. Reference 9, “Ophthalmology References”