An instrument for subjective measurement of tonic accommodation has been established based on the Badal system and Scheiner principle. The results of tonic accommodation between subjective measurement and objective measurement have no significant difference. Its establishment is important for the measurement of accommodation parameter in the myopia research center.
Accommodation, Ocular ; physiology ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Humans ; Optometry ; instrumentation ; methods ; Refractometry ; instrumentation ; methods ; Visual Acuity

According to the mechanism of spectral domain optical coherence tomography, this paper gives a design and development of a practical OCT imaging device based on slit-lamp microscopic widely-used in ophthalmology. The paper details the device's architecture and three key points in design: communication between PC and MCU, how to design modules of fixation lamp and reference arm and anti-interference measures.
Diagnostic Techniques, Ophthalmological ; instrumentation ; Equipment Design ; Tomography, Optical Coherence ; instrumentation ; methods

PURPOSE: Pupillary examination is an important objective method to diagnose lesions of the anterior visual pathways. However, errors and faults may easily alter the interpretation and value of the test as it is highly dependent on the examiner's skills. Therefore, we tried to develop a pupillography which is independent of the examiner. METHODS: Hardware composed of a binocularly measuring instrument adapted for an infrared charge coupled device (CCD) was developed. Two arrays of infrared light emitting diodes (LED) were supplied in front of each of the subject's eyes. A microcontroller to modulate these LED was developed, as was software to save and analyze the pupil images. The hardware was able to deliver a light to either eye or to both eyes, and to change the time, frequency, and intensity of the stimulus. The software automatically analyzed the pupil size and location by image processing. Pupil size was calculated continuously. After artifact elimination, the response amplitudes of the pupils were determined for the right and left pupils. RESULTS: Pupillary images of size 320 x 240, at 30 frames/second, were saved and processed to evaluate the change of the actual pupil size and the velocity of pupillary response. CONCLUSIONS: A pupillography to measure, save and analyze the pupillary response using image processing was developed. Further detailed clinical studies with a large number of patients will be required to validate this new method.
Diagnostic Techniques, Ophthalmological/*instrumentation ; Equipment Design ; Humans ; *Image Processing, Computer-Assisted ; *Reflex, Pupillary

PURPOSE: To compare and evaluate the total and internal aberrations measured by two aberrometers: the laser ray tracing aberrometer (iTrace, Tracey Technology) and the automatic retinoscope aberrometer (OPD Scan, Nidek). METHODS: A total of 54 healthy eyes were enrolled in the study. Following pupil dilation, aberrations were measured with the iTrace and OPD Scan. We compared the aberrations obtained from measurements obtained at pupillary diameters of 4 mm and 6 mm with the OPD Scan and iTrace. Aberrations of internal optics and total aberrations were compared for the two aberrometers. For each aberrometer and each eye, the averaged Zernike data were used to calculate various root-mean-square (RMS) data. These parameters, together with the refractive parameters, were then analyzed and complimented by paired t-tests. RESULTS: At a pupil diameter of 4 mm, the number of total aberrations in the entire eye showed significant differences for the mean values of spherical aberrations (Z4,0) obtained with the OPD Scan and iTrace aberrometers (p=0.001). Aberrations of the internal optics showed significant differences in the mean values of total RMS, coma (Z3,-1), and trefoil (Z3,3) between the iTrace and OPD Scan (p<0.001, p=0.01, p<0.001) for the same pupil diameter of 4 mm. At a pupil diameter of 6 mm, the two instruments showed a similar number of total aberrations. Aberrations of the internal optics showed significant differences in the mean values of total RMS, spherical aberration (Z4,0), and coma (Z3,-1) between the two devices (p<0.001, p=0.01, p<0.001). CONCLUSIONS: The iTrace and OPD Scan showed the largest number of differences for aberrations of internal optics rather than total aberrations for both pupil diameters. These results suggest that in healthy eyes, the two aberrometers may vary in some details. The aberrometers showed more agreement at a pupil diameter of 6 mm compared to 4 mm.
Adult ; Diagnostic Techniques, Ophthalmological/*instrumentation ; Humans ; Pupil/physiology ; Refractive Errors/*diagnosis ; Reproducibility of Results

A vernier optometer, based on the Scheiner principle, that makes use of polarized light, is designed and developed. It is specialized in measurement of tonic accommodation, accommodation and accommodation response. The vernier optometer has been proved by chinical testing results, to be a reliable and effective instrument with fine stabilily, good repeatability and sensitivity for short sight study relating to oculogyral parameters.
Accommodation, Ocular ; Adult ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Equipment Design ; Humans ; Myopia ; diagnosis ; Optometry ; instrumentation ; Refraction, Ocular ; Reproducibility of Results ; Visual Acuity

This paper presents a vision-based method for the width of NC membrane online inspection. In the production of bio-test strip, the number of antigen or antibody which is coated on the membrane depends on the width and the uniformity of test line T and control line C. People should control the width and the uniformity strictly to ensure the accuracy of lines in order to achieve quantitative inspection with high sensitivity. And online inspection must be done, it cannot be processed when the solution has been dry up. This paper gives a design of online inspection system based on linear charge-coupled device (linear CCD), it makes such advantages in terms of speed, accuracy, and the operation to achieve real-time, online inspection.
Biosensing Techniques ; instrumentation ; Diagnostic Techniques, Ophthalmological ; Enzyme-Linked Immunosorbent Assay ; Gold Colloid ; chemistry ; Humans ; Immunosorbent Techniques ; instrumentation ; Online Systems ; Photometry ; instrumentation ; Reagent Strips ; Vision Tests ; instrumentation ; methods ; Vision, Ocular ; Visual Acuity

Slit lamp bio-microscope image analysis system can provide objective and quantitative diagnosis evidences for ophthalmologists and make available efficient storing, management and intercourse of sufferer information and diagnosis results. In this paper, the system is discussed on its devices, software structure, analysis process and algorithm.
Algorithms ; Conjunctival Diseases ; diagnosis ; Corneal Diseases ; diagnosis ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Eye Diseases ; diagnosis ; Humans ; Image Enhancement ; instrumentation ; methods ; Image Interpretation, Computer-Assisted ; instrumentation ; methods ; Information Storage and Retrieval ; methods ; Ophthalmoscopy ; methods ; Software

PURPOSE: To investigate normative angle kappa data and to examine whether correlations exist between angle kappa and ocular biometric measurements (e.g., refractive error, axial length) and demographic features in Koreans. METHODS: Data from 436 eyes (213 males and 223 females) were analyzed in this study. The angle kappa was measured using Orbscan II. We used ocular biometric measurements, including refractive spherical equivalent, interpupillary distance and axial length, to investigate the correlations between angle kappa and ocular biometry. The IOL Master ver. 5.02 was used to obtain axial length. RESULTS: The mean patient age was 57.5 +/- 12.0 years in males and 59.4 +/- 12.4 years in females (p = 0.11). Angle kappa averaged 4.70 +/- 2.70 degrees in men and 4.89 +/- 2.14 degrees in women (p = 0.48). Axial length and spherical equivalent were correlated with angle kappa (r = -0.342 and r = 0.197, respectively). The correlation between axial length and spherical equivalent had a negative correlation (r = -0.540, p < 0.001). CONCLUSIONS: Angle kappa increased with spherical equivalent and age. Thus, careful manipulation should be considered in older and hyperopic patients when planning refractive or strabismus surgery.
Anterior Chamber/*pathology ; *Axial Length, Eye ; Diagnostic Techniques, Ophthalmological/*instrumentation ; Equipment Design ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Morbidity/trends ; Refractive Errors/*diagnosis/epidemiology ; Republic of Korea/epidemiology ; Retrospective Studies

BACKGROUNDMeasurement of anterior segment parameters plays an important role in diagnosis and treatment of glaucoma. The objective of this study was to evaluate the repeatability and reproducibility of anterior chamber volume (ACV) measurements with rotating scheimpflug camera (RSC) and to examine agreement with anterior segment optical coherence tomography (AS-OCT).

METHODSThirty nine healthy normal subjects were recruited from the Eye Center of Tongren Hospital. ACV was measured using RSC and AS-OCT in a randomly selected eye for each subject. For RSC measurements, both automatic and manual ACV measurements and 2 independent operators' ACV measurements were obtained. All subjects were invited for 3 visits within a week to evaluate repeatability and reproducibility of ACV measurement by RSC. Agreement was evaluated between RSC and AS-OCT.

RESULTSGood repeatability and reproducibility were found for both automatic and manual ACV measurements obtained by RSC. For intrasession repeatability, coefficient of variation (CVw) and intraclass correlation coefficient (ICC) values for automatic were 3.52% and 0.98; the values for manual were 3.44% and 0.97, respectively. For intersession reproducibility, the respective CVw and ICC values were 3.96% and 0.96. Good agreement was also found in 2 operators for both automatic and manual ACV measurements; nevertheless, poor agreement was found between RSC and AS-OCT (95% confidence interval (CI) for agreement of automatic RSC measurement versus AS-OCT were -96.3 to 72.8 microl and 95% CI for agreement of manual RSC measurement versus AS-OCT were between -41.7 to 10.1 microl).

CONCLUSIONSBoth RSC automatic and manual ACV measurements showed good repeatability and reproducibility, and showed comparable agreement between 2 independent operators, but poor agreement was found between RSC and AS-OCT.

Adult ; Anterior Chamber ; anatomy & histology ; Anterior Eye Segment ; anatomy & histology ; Cornea ; anatomy & histology ; Diagnostic Techniques, Ophthalmological ; instrumentation ; Female ; Glaucoma ; diagnosis ; Humans ; Male ; Reproducibility of Results ; Tomography, Optical Coherence ; methods ; Young Adult

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.
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