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Purpose: To record and evaluate the reliability parameters (fixation loss (FL) %, false positive (FP) %) and global indices (mean sensitivity (MS), mean deviation (MD), pattern standard deviation in dB) in three visual field test sessions within two weeks to assess the learning effect in normal healthy subjects and POAG patients and comparison of learning effect gender wise and age wise in primary open?angle glaucoma (POAG) patients. Methods: This study was a prospective observational study. An oculus visual field testing was done and analyzed in 30 eyes of POAG patients and 30 eyes of normal healthy subjects in three visits. Results: There were 16 (53.3%) males and 14 (46.6%) females in the POAG group and 16 (53.33%) males and 14 (46.66%) females in the normal healthy subject group. A significant difference in data change between each visit in FL, FP, MD, MS was found though the difference was more pronounced in the second visit than in the third visit. The pattern standard deviation does not change significantly in subsequent visits in both groups. Gender wise and age wise no significant difference was found in the POAG group. Conclusion: Significant improvement in reliability parameters and global indices with each subsequent visit in both the POAG group and normal patients signifies the importance of learning effect on these parameters and the need to perform at least three tests to get the baseline perimetry chart, especially in POAG patients, while in normal subjects, second perimetric result can be accepted. It was also concluded that the learning effect is not influenced by age and gender.
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La perimetría tradicional estándar es la base de la introducción de innovaciones no convencionales, que continúan considerándola como punto de referencia para comparar su eficiencia y señalar sus desventajas. Aunque la mayoría de estas contribuciones se centran en el glaucoma, también existen informes significativos sobre resultados satisfactorios en otras enfermedades. El propósito de esta revisión es abordar la tendencia emergente de las pantallas y monitores de última generación que se integran con las computadoras. Estos avances resaltan la accesibilidad mejorada, la introducción de nuevos equipos y la incorporación de nuevos pasos, variables y grupos etarios. La búsqueda de información se concentró en la literatura publicada en línea, especialmente en inglés, de los últimos 5 y 17 años. En total, se identificaron y recuperaron 24 artículos: 17 de los últimos cinco años y 7 de los últimos 17 años. Se registraron 18 tecnologías diferentes que compararon sus resultados con la perimetría estándar. Estas tecnologías se clasificaron, para los propósitos del estudio, en dos categorías: aquellas basadas en computadora (en línea y fuera de línea) y aquellas asistidas por el monitor y acopladas a simulación.
Standardized traditional perimetry is the basis for the introduction of unconventional innovations, which continue to be considered as a benchmark to compare its efficiency and point out its disadvantages. Although most of these contributions focus on glaucoma, there are also significant reports of successful results in other diseases. The purpose of this review is to address the emerging trend of state-of-the-art screens and displays integrated with computers. These advances highlight improved accessibility, the introduction of new equipment, as well as the incorporation of new steps, variables and age groups. The search for information focused on the literature published online, especially in English, between the last 5 to 17 years. A sheer number of 24 articles were identified and retrieved, 17 from the last 5 years and 7 from the last 17 years. Eighteen different technologies were identified, whose results were compared to those of standardized perimetry. These technologies were classified, for the purposes of the study, into two categories: computer-based (online and offline), or display-assisted and simulation-coupled.
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Background: Ocular morbidity with an early onset can have a significant impact on the long-term development of an individual. Hence, careful assessment of visual functions early on is very important. However, testing infants always poses a challenge. Standard tools to assess infants’ visual acuity, ocular motility, and so on rely on the clinician’s quick subjective judgments of an infant’s looking behavior. Eye movements are usually observed from head rotations or spontaneous eye movements in infants. Judging eye movements in the presence of strabismus is even more challenging. Purpose: This video shows a 4-month-old infant’s viewing behavior captured during a visual field screening study. The recorded video aided in the examination of this infant that was referred to a tertiary eye care clinic. The additional information captured through the perimeter testing is discussed. Synopsis: The Pediatric Perimeter device was developed to address visual field extent and gaze reaction time assessment in the pediatric population. As a part of a large-scale screening study, infants’ visual fields were tested. During this screening, a 4-month-old infant presented with a ptosis in the left eye. The infant was consistently missing the light stimuli presented in the left upper quadrant in the binocular visual field testing. The infant was referred to a tertiary eye care center to a pediatric ophthalmologist for further examination. During clinical examination, the infant was suspected to either have congenital ptosis or monocular elevation deficit. But the diagnosis of the eye condition was unsure owing to the poor cooperation of the infant. With the aid of Pediatric Perimeter, the ocular motility was consistent with limitation of elevation in abduction, indicating a possible monocular elevation deficit with congenital ptosis. The infant was also noted to have Marcus Gunn jaw-winking phenomenon. The parents were assured and asked for a review in 3 months. In the subsequent follow-up, the Pediatric Perimeter testing was performed, and the recording showed a full extraocular motility in both eyes. Hence, the diagnosis was changed to only congenital ptosis. The probable explanation for missing the target in the left upper quadrant in the first visit is postulated further. The left upper quadrant is the superotemporal visual field of the left eye and the superonasal visual field of the right eye. As the left eye had ptosis, the superotemporal visual field could have been obstructed and hence the stimuli missed. The normative extent for the nasal and superior visual field is just about 30° for a 4-month-old infant. Hence, the right eye also perhaps missed the stimuli in its superonasal visual field extent. This video highlights the utility of the Pediatric Perimeter device in providing a magnified view of the infant’s face along with greater visibility of ocular features from the infrared video imaging. This can potentially help the clinician to easily observe different ocular/facial abnormalities such as extraocular motility disorders, lid functions, and in identifying unequal pupil size, media opacities, and nystagmus. Highlights: The presence of congenital ptosis in younger infants might predispose as superior visual field defect and could also masquerade as a limitation in elevation.
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Purpose: To compare the effect of audiovisual and verbal instructions on patient performance while performing automated Humphrey visual field testing. Methods: This was a prospective study. A total 120 patients divided into groups of 40 each were recruited from the glaucoma outpatient department (OPD). All patients were aged 35–75 years with no previous experience of performing HFA. Patients with hearing impairment, any other cognitive impairment, and best?corrected visual acuity (BCVA) ?6/36 on Snellen’s visual acuity were excluded. The first two groups were given strict (conservative) and lenient (liberal) verbal instructions. The instructions were adapted from those listed in the manufacturer’s instruction. and the third group was shown a standard video depicting in detail how perimetry was to be performed. A questionnaire was given to each patient before and after the test to assess the patient’s performance. Results: Patients diagnosed with glaucoma during testing in each group were 29 (72.50%), 30 (75.0%), and 33 (82.5%) in the video instructed, strictly verbal, and leniently verbal groups, respectively. The overall mean deviation (MD) in the right eye (RE) was of ? 3.38 (?4.9 to 1.9) and in the left eye (LE) was ? 3.96 (?6.4 to ? 1.9). Reliable field was slightly higher for the video instructed group (47.5%) and lowest for the strictly verbal group (22.5%) (P = 0.033). A higher number of patients were very motivated in the video instructed group (27%) (P = 0.041). Post?test questionnaires showed that 40% of patients felt they have performed the test with 100% accuracy in video group with less guessing. A higher number of patients in the video instructed group (85%) felt instruction was helpful in performing the test (P = 0.001). Conclusion: The video groups were more motivated and had better confidence to perform the test with less anxiety and stress and with probably better understanding of the procedure due to visual effects enhancing their understanding.
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Background: As perimetry is a psychophysical test, the thresholds obtained are not only dependent on the functional architecture of the visual system but also on a variety of physical and cognitive factors. Factors such as, Lens rim artifact, improper refraction, miosed pupil and blepharoptosis, can affect luminance thresholds. Additionally, cognitive factors such as patient's attention, motivation, fatigue, and response bias can influence the obtained thresholds. Purpose: The video describes identification of various artifacts in Humphrey visual field printout and it has some useful teaching points to recognize and learn. Synopsis: Visual field test is critical for assessment and to document progression of glaucoma, but is prone to errors and artifacts. Fortunately, the patterns of such artifactual field loss are often characteristic and easily recognizable. Highlights: Several types of errors canlead to inaccurate results. Proper instructions and patient supervision during the test helps to improve the test results. The technician should ensure correct patient’s data entry. Careful examination of the obtained data on the printout is essential to detect any errors that can lead to misinterpretation of visual field, false alarms, and wrong clinical conclusion.
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Purpose: To compare the retinal sensitivities between the blue?on?yellow perimetry (BYP)/short?wavelength automated perimetry (SWAP) and green?on?yellow perimetry (GYP) among patients with and without nuclear sclerosis among glaucoma suspects. Methods: After ophthalmic examination, patients were subjected to two perimetric tests: BYP and GYP. The visual field (VF) parameters were compared between the two perimeters (p < 0.05 was considered significant). Results: Fifty?five eyes of 39 patients with a mean age of 60.53 ± 9.70 years were included in the study. Twenty?one eyes had clear lens or pseudophakia. Twenty?six eyes had lower grades of nuclear sclerosis (NO2NC2, NO3NC3) and eight eyes had higher grades of cataract (NO4NC4, NO5NC5). The mean retinal sensitivity (RS) in BYP was 22.08 ± 5.02 (dB) and in GYP was 23.84 ± 5.50 (dB) (p = 0.08). The mean defect in BYP was ?2.56 ± 4.40 (dB) and in GYP was ?3.24 ± 5.05 (dB), pattern standard deviation (PSD) in BYP was 3.65 ± 1.91 (dB) and in GYP was 3.83 ± 1.99 (dB), and foveal threshold (FT) was 24.20 ± 4.32 (dB) in BYP and 28.10 ± 4.50 (dB) in GYP. The two perimeters showed good agreement by the Bland–Altman plot for all parameters. Fourteen eyes showed perimetric changes suggestive of glaucoma by BYP. In these, GYP had a sensitivity of 92.86% (95% CI of 66.13% to 99.82%) and specificity of 95.12% (95% CI of 83.47% to 99.40%). Conclusion: BYP and GYP show good agreement. They are comparable in clear media as well as in different grades of nuclear sclerosis. GYP showed good sensitivity and specificity compared to BYP.
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Background: The normative data set in authomated perimetry is predominantly of non?Indian origin and hence may not be an accurate basis for visual field analysis in Indian population.This video describes an attempt to create a native normative dataset for automated perimetry, which can then be fed in our machines and be used as the normative database. Purpose: To formulate normative data and to increase domain knowledge of normative values for automated perimetry in Indian population of different age groups. Synopsis: Cross?sectional study conducted on patients receiving outpatient care in a span of 3 years, which included 6586 healthy normal patients (13172 eyes) with vision 6/6 unaided or after refractive correction. The patients were tested with 30?2 SITA FAST threshold algorithm on Humphrey Field Analyzer Model no: 745i. Normative data was calculated on basis of age group ranging from 19?75 years categorized to every decade. Normal values were formulated on basis of perimetry performed on normal patients. Highlights: Our work on creating a native normative dataset may add value as well as increase the accuracy of perimetry analysis in Indian eyes
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@#AIM: To evaluate the diagnostic performance of the isolated-checked visual evoked potential(IC-VEP)in the detection of open angle glaucoma and compared it to the blue-yellow perimetry(B/YP)and optical coherent tomography(OCT).<p>METHODS: In a retrospective analysis, IC-VEP, perimetry and OCT were performed on 101 subjects(<i>n</i>=35, normal; <i>n</i>=30, early glaucoma; <i>n</i>=36, moderate and advanced glaucoma)from China. The sensitivity of IC-VEP, perimetry and OCT for detection of glaucoma, as well as the agreement within these 3 methods, were calculated to evaluate their clinic performance.<p>RESULTS: In the early primary open angle glaucoma(POAG)group the sensitivity of IC-VEP, blue-yellow perimetry and OCT were 70.00%, 70.00% and 63.33%, respectively. In the moderate advanced POAG group, the sensitivity of IC-VEP, OCT and blue-yellow perimetry were 86.11%, 88.89% and 91.67%, respectively. The specificity of IC-VEP was 91.43%. The results of IC-VEP were highly consistent with OCT and blue-yellow visual field tests(kappa: 0.721-1.000, <i>P</i><0.05).<p>CONCLUSION:As an objective examination of visual function, IC-VEP can be used for early diagnosis of glaucoma. It may be a useful tool for monitoring the function of RGCs in suspected glaucoma patients.
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Purpose: Glaucoma is the leading cause of irreversible blindness in the world. The current study aims to estimate prevalence, features, and associations of open angle glaucoma (OAG) in a rural and urban East Indian population. Methods: This is a population based cross sectional study with two arms, rural (28 contiguous villages from 13 Gram Panchayats in Balagarh Police Station, Hooghly district) and urban (Kolkata). Individuals residing in the study area aged 40 years and above were included using multistage random cluster sampling. All subjects underwent a detailed ophthalmic examination at our base hospitals including applanation tonometry, ultrasound pachymetry, gonioscopy, and frequency doubling technology perimetry. The primary outcome was the prevalence of POAG (95% CI). Age and gender specific prevalence estimates were calculated. Multiple logistic regressions were used to analyze the risk factors. Results: Data from 7128 and 6964 subjects aged 40 years or older from Kolkata city and Hooghly district, respectively were analyzed. In the urban population, 2.10% (95% CI: 1.99–2.21%) had POAG and 0.15% (95% CI: 0.13–0.17%) had secondary OAG. In the rural population, 1.45% (95% CI: 0.59–2.31%) had POAG and 0.10 ± 0.03% (95% CI: 0.07–0.13%) had secondary OAG. Conclusion: The study concludes that higher age, higher vertical cup disc ratio (VCDR), and lower central corneal thickness (CCT) are important independent predictors of OAG and emphasizes that increased intraocular pressure (IOP) is not POAG. Gonioscopy, disc evaluation, and screening perimetry need to be incorporated in the detection protocol for glaucoma if we intend to lighten the burden of blindness due to glaucoma.
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@#AIM: To evaluate visual field of the unilateral visually impaired applicants by a custom program test of Humphrey perimeter, which was indispensable for car driving.<p>METHODS: A retrospective study was performed. The process of a custom defined Humphrey ‘1 EYE Screening' program was set covers field region from temporal 90° to nasal 60°, and over 30° vertically away from the horizontal line. The candidates were qualified eligibility by range of visual field and reliability of the results. This study conducted statistics on the applicants who fulfilled the test from July 1st, 2016 to June 30th, 2017, and compared the impact factors of the pass rate.<p>RESULTS: After excluding repeated measurement reports, this study included 618 subjects, the most common causes of these eyes impaired were ocular trauma(49.7%)and unhealed amblyopia(29.3%). A total of 497 candidates(80.4%)passed the test. 85 of the 121 failure cases(70.2%)were due to a limitation of the nasal visual field(less than 60°), and 12 cases were failed by fixation loss because of nystagmus or poor cooperation. Compared with the test failure group, the subjects in the passing group are older, the average correct response points is more, and the average test time is shorter, all with statistically significant differences(<i>P</i><0.05). In the passing group, the proportion of subjects with equivalent spherical mirror <0.5D was 77.5%, which was significantly higher than 62.8% in the failure group(χ2=7.264, <i>P</i>=0.007).<p>CONCLUSION: The custom program ‘1 EYE Screening' of Humphrey perimetry can be used to qualify eligibility of driving for unilateral visual impaired applicants. In order to prevent peripheral interfering from eye frames, corneal contact lenses were recommended for applicants with refractive errors.
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@#AIM: To evaluate visual field of the unilateral visually impaired applicants by a custom program test of Humphrey perimeter, which was indispensable for car driving.<p>METHODS: A retrospective study was performed. The process of a custom defined Humphrey ‘1 EYE Screening' program was set covers field region from temporal 90° to nasal 60°, and over 30° vertically away from the horizontal line. The candidates were qualified eligibility by range of visual field and reliability of the results. This study conducted statistics on the applicants who fulfilled the test from July 1st, 2016 to June 30th, 2017, and compared the impact factors of the pass rate.<p>RESULTS: After excluding repeated measurement reports, this study included 618 subjects, the most common causes of these eyes impaired were ocular trauma(49.7%)and unhealed amblyopia(29.3%). A total of 497 candidates(80.4%)passed the test. 85 of the 121 failure cases(70.2%)were due to a limitation of the nasal visual field(less than 60°), and 12 cases were failed by fixation loss because of nystagmus or poor cooperation. Compared with the test failure group, the subjects in the passing group are older, the average correct response points is more, and the average test time is shorter, all with statistically significant differences(<i>P</i><0.05). In the passing group, the proportion of subjects with equivalent spherical mirror <0.5D was 77.5%, which was significantly higher than 62.8% in the failure group(χ2=7.264, <i>P</i>=0.007).<p>CONCLUSION: The custom program ‘1 EYE Screening' of Humphrey perimetry can be used to qualify eligibility of driving for unilateral visual impaired applicants. In order to prevent peripheral interfering from eye frames, corneal contact lenses were recommended for applicants with refractive errors.
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To investigate associations between central visual function and inner retinal structure in primary open-angle glaucoma (POAG). This study enrolled 78 POAG patients and 58 healthy controls. POAG was classified into early glaucoma and moderate to advanced glaucoma. The following tests were performed on all participants: isolated-check visual evoked potential (icVEP) testing, 24–2 standard automated perimetry (SAP), and Cirrus optical coherence tomography (OCT) examinations. Signal-to-noise ratio (SNR) measures obtained from icVEP responses to isolated checks presented at four depths of modulation (DOMs; 8%, 14%, 22%, and 32%) were explored. Mean macular sensitivity (mMS) was assessed by calculating the mean sensitivities of central 12 SAP points. Ganglion cell layer+ inner plexiform layer thickness (GCL+IPLT) and peripapillary retinal nerve fiber layer thickness (pRNFLT) were measured by OCT scanning. For each group of subjects, linear relationships among the following measures were analyzed: SNR, mMS, GCL+IPLT, and pRNFLT. SNR, mMS, GCL+IPLT, and pRNFLT were all more significantly decreased in glaucoma than in controls (P<0.001). A significant positive association was found between SNR at 14% DOM and GCL+IPLT at the inferior sector in early glaucoma (r=0.465, P=0.004). In moderate to advanced glaucoma, significant correlations were found between SNR at 32% DOM and mean GCL+IPLT (r=0.364, P=0.023), superior GCL+IPLT (r=0.358, P=0.025), and mean pRNFLT (r=0.396, P=0.025). In addition, in moderate to advanced glaucoma, there were significant correlations between mMS and all relevant measures of retinal thickness (r=0.330−0.663, P<0.010). In early glaucoma, significant correlations were found between mean mMS and minimum GCL+IPLT (r=0.373, P=0.023), and between inferior mMS and superior GCL+IPLT (r=0.470, P=0.003). Linear models provided a good explanation for the relationship between SNR and inner retinal thickness (IRT), whereas nonlinear models better explained the relationship between mMS and IRT. In early glaucoma, both SNR and mMS were related moderately and significantly to IRT, whereas in moderate to advanced glaucoma, mMS was more strongly correlated with IRT than SNR.
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Purpose@#To conduct an evaluation of juxtapapillary choroidal thickness of patients suspected with glaucoma obtained through spectral domain optical coherence tomography (SD-OCT) and correlate it with perimetry results.@*Methods@#Design: Cross-sectional Study. Population: 175 eyes diagnosed as “glaucoma suspect” had standard automated perimetry (SAP) to document the presence of functional glaucomatous damage using optimal near-point correction using the Humphrey Visual Field Analyzer II, 30-2 or 24-2 SITA-standard program. SD-OCT imaging of the retinal nerve fi ber layer (RNFL) was also done to look for structural glaucomatous damage and in using enhanced depth imaging of the optic nerve and the Cirrus caliper tool, choroidal thickness was measured at fi ve predetermined points temporal and nasal from the optic nerve. The population was classifi ed into two groups: Group 1 are those with structural or functional glaucomatous damage (n=68) and Group 2 were those without (n=107).@*Results@#One-Way Multivariate Analysis of Covariance was used in comparing the mean temporal and nasal choroidal thickness scores of the two groups. There are no statistical differences in terms of the mean temporal choroidal thickness (p=0.856) and mean nasal choroidal thickness (p=0.734) between patients with and without glaucomatous damage. The mean temporal and nasal choroidal thickness scores of the two groups at different juxtapapillary locations: 0 μm, 250 μm, 500 μm, 750 μm and 1000 μm away from the disc were also not statistically different.@*Conclusion@#Results show that from this present cohort of glaucoma suspect patients, juxtapapillary choroidal thickness is not correlated with structural and functional glaucomatous damage.
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Visual Field Tests , Tomography, Optical Coherence , Ocular HypertensionABSTRACT
Glaucoma is the irreversible blind eye disease and many glaucoma patients have severe optic nerve and visual field defect in their initial diagnosis.Therefore,visual field is critical to the evaluation of glaucoma damage.However,the testing time is too long and the conventional standard automatic perimetry is not convenient to carry,which limits its application in the diagnosis of glaucoma.At present,a variety of portable perimetries and softwares have been developed,and its rapid,effective and portable features are convenient for the diagnosis of glaucoma.This article summarized the advances in the application of various portable perimetry,which have been used to evaluate the glaucomaous visual field defect.
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Purpose: To estimate the prevalence, features, and associations of primary angle closure disease (PACD) in rural and urban populations from West Bengal in eastern India. Methods: This was a population-based cross-sectional study with two arms, rural and urban. The rural study area consisted of 28 contiguous villages from 13 gram panchayats in Balagarh Police Station, with rural base hospital at Dhobapara, Balagarh Police Station, in the village Kuliapara of Hooghly district. A tertiary eye hospital in central Kolkata was the urban study center. Individuals residing in the study area aged 40 years and above were included in this study using multistage random cluster sampling. All subjects underwent a detailed ophthalmic examination at our base hospitals including applanation tonometry, ultrasound pachymetry, gonioscopy, and frequency doubling technology perimetry. Data collected were analyzed using SPSS 13. Multiple logistic regressions were used to analyze risk factors for PACD. Results: A total of 7,408 and 7,248 subjects aged 40 years or older were enumerated from Hooghly district and Kolkata city, respectively. PACD was detected in 1.9% subjects in rural arm and 1.54% subjects in the urban arm (P < 0.001). In rural arm, 0.3% had PACS, 0.56% had PAC, and 1.03% had PACG. In urban arm, 0.22% had PACS, 0.35% had PAC, and 0.97% had PACG. Conclusion: The study concludes that higher age, higher CCT, and shorter axial length/presence of hyperopia are important independent predictors of ACD. ACD is more common in eastern India than previous estimates.
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BACKGROUND: The present study investigated the diagnostic effectiveness of an LCD-based visual field testing system (LVF) in comparison with the standard automated perimetry Humphrey Field Analyzer II-750i (HFA). METHODS: A randomized controlled crossover study was conducted with 202 normal and 128 glaucomatous eyes using both LVF and HFA. The visual field testing systems were compared in terms of mean deviation (MD), pattern standard deviation (PSD), and area under the receiver operating characteristics curve (AUC) of MD and PSD differentiating the normal and glaucomatous eyes. RESULTS: Significant correlations were found between MD measurements from LVF and those from HFA for normal eyes (r = 0.342) and glaucomatous eyes (r = 0.796); slightly higher significant correlations were identified between PSD measurements from LVF and those from HFA for normal eyes (r = 0.363) and glaucomatous eyes (r = 0.828). Furthermore, high AUCs of MD were found as 0.786 for LVF and 0.868 for HFA and AUCs of PSD as 0.913 for LVF and 0.932 for HFA. CONCLUSION: The comparison results of the present study support the competence of LVF compared with HFA in visual field testing for early detection of glaucoma.
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Area Under Curve , Cross-Over Studies , Glaucoma , Mental Competency , ROC Curve , Visual Field Tests , Visual FieldsABSTRACT
PURPOSE: To compare the variability of standard automated perimetry (SAP) between patients with preperimetric glaucoma (PPG) and normal controls. METHODS: This study included 67 eyes, classified into the following groups: 30 eyes, normal controls; and 37 eyes, PPG. All subjects were examined with 24-2 Humphrey static perimetry. The visual field was divided into superonasal, superotemporal, inferonasal, and inferotemporal sectors. The variability of SAP was obtained using the standard deviation of sensitivity points at each location. We compared the variability of SAP between the normal controls and PPG patients. RESULTS: The variability of SAP was higher in the PPG group compared with the normal control group (p < 0.001). There was also a significant correlation between the variability of SAP and intraocular pressure fluctuations and retinal nerve fiber layer thickness (both p < 0.05). The variability of SAP in the PPG group was higher (p < 0.05) in all areas except the inferotemporal sector compared with the normal control group. CONCLUSIONS: The variability of the SAP increased in PPG patients compared with normal controls, even when the visual field test results were normal.
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Humans , Glaucoma , Intraocular Pressure , Nerve Fibers , Retinaldehyde , Visual Field Tests , Visual FieldsABSTRACT
The purpose of this study was to characterize, differentiate and correlate visual field and brain activation in visual cortex for normal, glaucoma suspect (GS) and primary open angle glaucoma (POAG) participants using Standard Automated Perimetry (SAP) and functional Magnetic Resonance Imaging (fMRI) respectively. The fMRI scans and SAP test were both carried out in Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM). Two types of black-and-white checkerboard pattern were displayed to the participants during the fMRI scans. The fMRI data were analyzed using WFU pickatlas toolbox targeting visual cortex area. The results showed that there was no significant difference in number of activated voxel between the three groups in visual cortex (BA 17, 18 and 19) while viewing all the given stimuli (p > 0.05). The pattern standard deviation (PSD) of SAP for visual field also revealed no significant differences (p > 0.05) in all groups of participants. However, negative correlation between PSD and fMRI activation was observed. The PSD values increased with a decrease in fMRI activation. With reference to visual field analysis, the results suggest that glaucomatous neuropathy of POAG patients has led to a gradual decrease in visual cortex activation and a gradual increase in PSD.
Subject(s)
Visual Cortex , Magnetic Resonance Imaging , Magnetic Resonance SpectroscopyABSTRACT
AIM: To evaluate the anatomic and visual outcomes of 25-gauge vitrectomies combined with air tamponade for the treatment of idiopathic macular hole (IMH).METHODS: Thirty eyes of 27 patients with IMH were included in this prospective interventional study.All patients underwent 25-gauge pars plana vitrectomy (PPV) combined with phacoemulsification and air tamponade.Best corrected visual acuity (BCVA, logMAR), perimetry and multifocal electroretinography (mfERG) were conducted before and after the operation.Anatomical changes were evaluated with optical coherence tomography (OCT).RESULTS: The macular holes closed successfully in 28 eyes after the primary vitrectomy.The mean BCVA improved from 0.72±0.22 logMAR preoperatively to 0.29±0.18 logMAR postoperatively (P<0.001).In the visual field of central 10°, the average mean deviation (MD) decreased from-3.59±1.83 dB preoperatively to-2.51±1.36 dB postoperatively (P<0.001) and the average pattern standard deviation (PSD) decreased from 1.86±0.68 dB preoperatively to 1.33±0.32 dB postoperatively (P=0.001).The retinal response densities of mfERG in the foveal and perifoveal area increased significantly, and implicit times of rings 4-6 prolonged significantly (P<0.05).The symptom duration and baseline N1 amplitude densities at ring 1 had a significant impact on postoperative BCVA (P<0.001, P=0.001, respectively).CONCLUSION: The 25-gauge PPV and air tamponade with 1 day prone positioning produce favorable anatomic and functional outcomes.
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Context: Glaucoma is the leading cause of global irreversible blindness. No recent study with adequate sample size has been carried out to estimate glaucoma prevalence in Eastern India. Aims: The aim of this study was to assess and compare the prevalence and types of glaucoma in a rural and urban East Indian population. Settings and Design: The Hooghly River Glaucoma Study (HRGS) is a population‑based cross‑sectional study from West Bengal. A tertiary hospital in Kolkata was our urban study center. Our rural study area included 28 contiguous villages from the district of Hooghly surrounding the rural base hospital located at Dhobapara in village Bakulia. Individuals aged 40 years and above were included in this study. Subjects and Methods: All subjects underwent a detailed ophthalmic examination at our base hospitals including applanation tonometry, ultrasound pachymetry, gonioscopy, and frequency doubling technology perimetry. Glaucoma was defined using modified International Society of Geographical and Epidemiological Ophthalmology criteria. Statistical Analysis Used: Analysis was performed using Chi‑square test and multiple logistic regression using SPSS. Results: Totally, 14,092 individuals participated; 2.7% were detected to have glaucoma in rural arm and 3.23% in urban arm (P < 0.001). In urban population, 2.10% had primary open angle glaucoma (POAG), 0.97% had primary angle closure glaucoma (PACG), and 0.15% had secondary glaucoma. In rural population, 1.45% had POAG, 1.15% had ACG, and 0.10% had secondary glaucoma. Conclusions: HRGS is the largest population‑based glaucoma study in India to date with glaucoma prevalence comparable to other landmark Indian studies. POAG was the most common form of glaucoma in our study population as well. PACG was more common in this region than previously thought.