Korean J Ophthalmol.  2011 Aug;25(4):252-256. 10.3341/kjo.2011.25.4.252.

Laser Peripheral Iridotomy with Iridoplasty in Primary Angle Closure Suspect: Anterior Chamber Analysis by Pentacam

• Lee JR
• Choi JY
• Kim YD
• Choi J

• KMID: 1018413
• DOI: http://doi.org/10.3341/kjo.2011.25.4.252

Abstract

PURPOSE
To compare conventional laser peripheral iridotomy (LPI) and LPI combined with laser peripheral iridoplasty in eyes with primary angle closure suspect (PACS) by assessment of anterior chamber dimensional changes using a Pentacam.
METHODS
Forty-eight eyes of 24 subjects with bilateral PACS were recruited consecutively. Each eye was randomly allocated to treatment with conventional LPI, argon LPI only, or LPI plus iridoplasty, which consisted of simultaneous argon LPI and peripheral iridoplasty. Anterior chamber measurements were performed on each eye using a Pentacam, both before and after treatment. Mean anterior chamber depth (ACD), anterior chamber volume (ACV), and anterior chamber angle were measured, and topographic ACD analysis was performed. Results were compared between the two treatment groups.
RESULTS
After treatment with either conventional LPI or LPI plus iridoplasty, the mean ACD and ACV increased significantly. Topographic ACD analysis revealed that the mid-to-peripheral ACD increase was significantly greater in the LPI plus iridoplasty group than in eyes treated with conventional LPI. Intraocular pressure changes and post-LPI complications did not differ between the groups.
CONCLUSIONS
Compared with conventional LPI, our study showed that LPI plus iridoplasty improved the mid-to-peripheral ACD increase. This procedure may have a role as an adjunct for reducing angle closure by simultaneously eliminating pupillary and non-pupillary block components.

Keyword

Laser peripheral iridoplasty; Laser peripheral iridotomy; Pentacam; Primary angle closure suspect

MeSH Terms

Adult
Aged
Anterior Chamber/*pathology/surgery
Diagnostic Techniques, Ophthalmological/*instrumentation
Equipment Design
Female
Follow-Up Studies
Glaucoma, Angle-Closure/pathology/physiopathology/*surgery
Gonioscopy
Humans
Intraocular Pressure
Iridectomy/*methods
Iris/pathology/*surgery
Laser Therapy/*methods
Lasers, Solid-State
Male
Middle Aged
Prospective Studies
Tonometry, Ocular

Figure

• 

  Fig. 1 Conventional laser peripheral iridotomy (LPI) and the LPI combined with iridoplasty technique. (A) Conventional LPI refers to LPI alone. (B) The LPI combined with iridoplasty approach consists of LPI followed by laser peripheral iridoplasty administered in the same session. Yellow circle: LPI site, cyanine-blue circle: laser peripheral iridoplasty site; about 20 burn spots are placed alongside the limbus.

• 

  Fig. 2 Advanced anterior chamber depth (ACD) topographic parameters derived from routine ACD data from the Pentacam output. Central ACD is the average of ACD values at nine topographic points within 2 mm from the center of the eye; Mid1 ACD is the average of ACD measurements at 12 topographic points within 2 to 4 mm from the eye center; Mid2 ACD is the average of ACD values at 16 topographic points within 4 to 6 mm from the center of the eye; Mid3 ACD is the average of ACD measurements at 20 topographic points within 6 to 8 mm from the eye center.

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