Korean J Ophthalmol.  2016 Jun;30(3):206-213. 10.3341/kjo.2016.30.3.206.

Clinical and Anterior Segment Anatomical Features in Primary Angle Closure Subgroups Based on Configurations of Iris Root Insertion

• Hong JW
• Yun SC
• Sung KR
• Lee JE

• KMID: 2373976
• DOI: http://doi.org/10.3341/kjo.2016.30.3.206

Abstract

PURPOSE
To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion.
METHODS
Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT(0), IT(500), IT(750), and IT(1500)), lens vault, iris area, angle opening distance (AOD(500)), angle recess area (ARA(750)), and trabecular iris space area (TISA(750)) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG).
RESULTS
In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT(0) (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm2, p = 0.045), lower ARA(750) (0.112 ± 0.08 vs. 0.154 ± 0.08 mm2, p = 0.017) and AOD(500) (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG.
CONCLUSIONS
The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.

Keyword

Anterior segment optical coherence tomography; Anterior segment parameters; Iris root insertion; Primary angle closure

MeSH Terms

Anterior Eye Segment/*diagnostic imaging
Female
Glaucoma, Angle-Closure/diagnosis/physiopathology/*surgery
Gonioscopy
Humans
*Intraocular Pressure
Iridectomy/*methods
Iris/diagnostic imaging/*surgery
Lens, Crystalline/diagnostic imaging
Male
Middle Aged
Prospective Studies
Tomography, Optical Coherence/*methods

Figure

• 

  Fig. 1 Anterior segment parameters measured by anterior segment optical coherence tomography and calculated using the Image J software ver. 1.46 (National Institutes of Health, Bethesda, MD, USA). AOD500, 750 = angle opening distance; SS = scleral spur; IT0, 500, 750, 1500 = iris thickness; AA = anterior chamber area; ACD = anterior chamber depth; LV = lens vault; PD = pupil distance; IA = iris area; IC = iris curvature; TISA750 = trabecular iris space area; ARA750 = angle recess area.

• 

  Fig. 2 Location of iris root insertion. (A) Basal insertion and (B) non-basal insertion.

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