**10. Definitive examination**

When at least 1 finding suggested the presence of glaucoma, the subjects were recruited for definitive examination (Table 1). A definitive examination was performed when a subject was suspected to have glaucoma based upon the findings of the initial non-contact ocular exami‐ nation. The definitive examination consisted of the following procedures: slit-lamp biomicro‐ scopy, Goldmann applanation tonometry, gonioscopy, and optic nerve head evaluation using a Goldmann three-mirror lens (Haag-Streit International, Koeniz, Switzerland) and a visual field test with the Humphrey Field Analyzer II 24-2 SITA Standard Program (Carl Zeiss Meditec Inc, Dublin, CA, USA). Diagnosis of glaucoma was made based on optic disc appear‐ ance, including cup-to-disc ratio, rim width, nerve fiber layer defect, the visual field test, and the clinical records that were obtained through screening and definitive examinations. When present or suspected, glaucoma was categorized based upon the criteria of previous popula‐ tion studies (Table 2). In the definitive diagnosis, anomalous discs, including tilted discs, were carefully excluded. The final diagnosis of glaucoma was determined by 4 glaucoma specialists.

1) Intraocular pressure of 21mm Hg or higher in either eye

2) Presence of abnormalities in the stereoscopic fundus photographs, including one or more of the following glaucomatous changes:

1. Vertical cup/disc ratio of the optic nerve head was more than or equal to 0.6

2. Rim width at the superior portion (11-1 h), or inferior portion (5-7 h) was less than or equal to 0.2 of disc diameter ratio was

3. Difference in the vertical cup/disc more than or equal to 0.2 between both eyes

4. Nerve fiber layer defect or splinter disc hemorrhage was found

3) Failure to take stereoscopic fundus photographs

**Table 1.** Criteria for Definitive Examination Eligibility.

#### **Category 1**

**8. Participants**

258 Glaucoma - Basic and Clinical Aspects

participants were ethnically Japanese.

**9. Screening examination**

and the mean value was adopted.

**10. Definitive examination**

disc (eg, superior segmental optic disc hypoplasia).

disc photography by stereoscopic fundus camera (30o

This was a cross-sectional study in an institutional setting [24]. Subjects older than 30 years were recruited at an annual community health checkup project held in the city of Akita (with a population of 325,537), the capital of Akita Prefecture, Japan. A total of 1,173 subjects participated in the comprehensive examinations from September 10, 2007 to October 26, 2007. Of these, 710 individuals underwent glaucoma screening. All of the

This study was performed after the approval by the Ethical Committee of Akita Prefecture Health Care Foundation. All study procedures adhered to the principles outlined in the Declaration of Helsinki for research involving human subjects, and all participants gave

Exclusion criteria were (1) eyes with previous ocular surgery, trauma, or significant ocular disease; (2) eyes with any inborn aberrations, which might affect the morphology of the optic

The initial non-contact ocular examination was conducted by trained non-ophthalmologists and included measurement of refraction and keratometry (Topcon KR-8100PA, Tokyo, Japan), IOP by noncontact pneumotonometry (Topcon CT-90A, Tokyo, Japan), angle width (Scanning Peripheral Anterior Chamber Analyzer, Takagi Seiko, Nagano, Japan), non-mydriatic optic

Japan), and confocal laser scanning tomography (Heidelberg Retina Tomograph II, software version 3.0, Heidelberg Instruments, Heidelberg, Germany). IOP was measured three times,

When at least 1 finding suggested the presence of glaucoma, the subjects were recruited for definitive examination (Table 1). A definitive examination was performed when a subject was suspected to have glaucoma based upon the findings of the initial non-contact ocular exami‐ nation. The definitive examination consisted of the following procedures: slit-lamp biomicro‐ scopy, Goldmann applanation tonometry, gonioscopy, and optic nerve head evaluation using a Goldmann three-mirror lens (Haag-Streit International, Koeniz, Switzerland) and a visual field test with the Humphrey Field Analyzer II 24-2 SITA Standard Program (Carl Zeiss Meditec Inc, Dublin, CA, USA). Diagnosis of glaucoma was made based on optic disc appear‐ ance, including cup-to-disc ratio, rim width, nerve fiber layer defect, the visual field test, and the clinical records that were obtained through screening and definitive examinations. When

angle, 3-DX/NM, Nidek, Gamagori,

written informed consent for this research prior to their participation.

The vertical cup-to-disc ratio of the optic nerve head is 0.7 or more, or the rim width at the superior portion (11-1 h) or the inferior portion (5-7 h) is 0.1 or less of the disc diameter, or the difference of the vertical cup-to-disc ratio is 0.2 or more between both eyes, or a nerve fiber layer defect is found, and the hemifield based visual field abnormality is compatible with optic disc appearance or nerve fiber layer defect.

#### **Category 2**

When the visual field test is not reliable or available, the cup-to-disc ratio of the optic nerve head is 0.9 or more, or the rim width at the superior portion (11-1 h) or the inferior portion (5-7 h) is 0.05 or less of the disc diameter, or the difference of the vertical cup-to-disc ratio is 0.3 or more between both eyes

#### **Glaucoma suspect**

When the cup-to-disc ratio of the optic nerve head is 0.7 or more portion (5-7 h) is 0.1 or less but more than 0.05 of the disc diameter but less than 0.9, or the rim width at the superior portion (11-1h) or the inferior, or the difference of the vertical cup-to-disc ratio is 0.2 or more but less than 0.3 between both eyes, or the nerve fiber layer defect is found, and the visual field test is not reliable or available or does not show hemi-field based compatible defect, the eye is diagnosed with suspected glaucoma

**Table 2.** Criteria for Glaucoma Diagnosis.

#### **10.1. Category 1**

The vertical cup-to-disc ratio of the optic nerve head is 0.7 or more, or the rim width at the superior portion (11-1 h) or the inferior portion (5-7 h) is 0.1 or less of the disc diameter, or the difference of the vertical cup-to-disc ratio is 0.2 or more between both eyes, or a nerve fiber layer defect is found, and the hemifield based visual field abnormality is compatible with optic disc appearance or nerve fiber layer defect.

#### **10.2. Category 2**

When the visual field test is not reliable or available, the cup-to-disc ratio of the optic nerve head is 0.9 or more, or the rim width at the superior portion (11-1 h) or the inferior portion (5-7 h) is 0.05 or less of the disc diameter, or the difference of the vertical cup-to-disc ratio is 0.3 or more between both eyes

**30's 40's 50's 60's 70's Total**

73 (143, 10.9%)

57 (114, 8.7%)

130 (257, 19.6%)

29 (57, 2.2%)

15 (29, 2.2%)

44 (86, 6.6%)

354 (703, 53.7%) 261

http://dx.doi.org/10.5772/54556

304 (607, 46.3%)

658 (1310, 100%)

126 (252, 19.2%)

Screening for Narrow Angles in the Japanese Population Using Scanning Peripheral Anterior Chamber Depth Analyzer

114 (228, 17.4%)

240 (480, 36.6%)

**Table 3.** Number of patients and eyes and the percentage of eyes (in parenthesis) examined by SPAC in each age group.

Descriptive statistical analysis for the determination of mean±standard deviation (SD) for continuous values was performed with SPBS software (Nankodo Publisher, Statistical Package for the Biosciences version 9.51, Tokyo, Japan). Data from both eyes of each individual were used, as it was more efficient and informative than data for single eyes. Comparisons of the different SPAC parameters between males and females or among each age group were analyzed with paired and unpaired t tests. Pearson correlation coefficients were calculated to assess the strength of the correlations between SPAC parameters and potential confounders.

A glaucoma specialist judged that 26 eyes of 19 subjects required the definitive examination, and all 19 subjects were enrolled in the definitive examination. The definitive examination revealed that 1 subject had PACG (0.08%), 1 subject had PAC (0.08%), and 1 had ciliary cyst (0.08%). None of all these eyes showed IOP elevation of more than 21mm Hg. Laser iridotomy was performed on PACG and PAC subjects. None of these subjects presented with subjective

In male subjects of 30 to 60 years of ages, the central and the peripheral anterior chamber depths were gradually decreased with ages. There were significant differences in these depths among 30, 40, and 50 age groups (p<0.0001). However, there was no significant difference in depths between 60 years and 70 years age group (Fig. 5). In female subjects, the ACD tended to be shallower in women than in men in each generation. The central and the peripheral anterior chamber depths were gradually decreased with ages. There were significant differences among

symptoms that are thought to demonstrate a strong association with angle closure.

Association of gender and age with SPAC parameters are summarized in Table 4.

**Male**

**Female**

**Total**

**12. Data analysis**

**13. Results**

21 (42, 3.2%)

20 (40, 3.1%)

41 (82, 6.3%)

105 (209, 16.0%)

98 (196, 15.0%)

203 (495, 37.8%)

For all analyses, P<0.05 was considered statistically significant.

**13.1. Results of primary screening and definitive examination**

**13.2. Association of gender and age with SPAC parameters**

#### **10.3. Glaucoma suspect**

When the cup-to-disc ratio of the optic nerve head is 0.7 or more portion (5-7 h) is 0.1 or less but more than 0.05 of the disc diameter but less than 0.9, or the rim width at the superior portion (11-1h) or the inferior, or the difference of the vertical cup-to-disc ratio is 0.2 or more but less than 0.3 between both eyes, or the nerve fiber layer defect is found, and the visual field test is not reliable or available or does not show hemi-field based compatible defect, the eye is diagnosed with suspected glaucoma
