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Fulltext Retinotopic effects of visual attention revealed by dichoptic multifocal pupillography

Rosli Y, Carle CF, Ho Y, James AC, Kolic M, Rohan EMF, et al.

Sci Rep, 2018 02 14;8(1):2991.
PMID: 29445236 DOI: 10.1038/s41598-018-21196-1

Multifocal pupillographic objective perimetry (mfPOP) has recently been shown to be able to measure cortical function. Here we assessed 44 regions of the central 60 degrees of the visual fields of each eye concurrently in 7 minutes/test. We examined how foveally- and peripherally-directed attention changed response sensitivity and delay across the 44 visual field locations/eye. Four experiments were completed comparing white, yellow and blue stimulus arrays. Experiments 1 to 4 tested 16, 23, 9 and 6 subjects, 49/54 being unique. Experiment 1, Experiments 2 and 3, and Experiment 4 used three variants of the mfPOP method that provided increasingly improved signal quality. Experiments 1 to 3 examined centrally directed attention, and Experiment 4 compared effects of attention directed to different peripheral targets. Attention reduced the sensitivity of the peripheral locations in Experiment 1, but only for the white stimuli not yellow. Experiment 2 confirmed that result. Experiment 3 showed that blue stimuli behaved like white. Peripheral attention showed increased sensitivity around the attentional targets. The results are discussed in terms of the cortical inputs to the pupillary system. The results agree with those from multifocal and other fMRI and VEP studies. mfPOP may be a useful adjunct to those methods.

Matched MeSH terms: Visual Field Tests/methods*
Fulltext HbA1c and retinal sensitivity in diabetics using microperimetry

Sharanjeet-Kaur, Ismail SA, Mutalib HA, Ngah NF

J Optom, 2018 05 26;12(3):174-179.
PMID: 29843983 DOI: 10.1016/j.optom.2018.03.007

PURPOSE: The purpose of this study was to determine the relationship between HbA1c values and retinal sensitivity at central 10° using the MP-1 microperimeter.
METHODS: A prospective study was carried out on 32 healthy subjects (control group) and 60 diabetic patients. The diabetic patients were divided into 2 groups. Group 1 comprised of 30 patients without diabetic retinopathy (DR) and group 2 had 30 patients with mild non-proliferative DR. A full-threshold microperimetry of the central 10° of retina (the macula) was performed on all subjects, utilizing 32 points with the MP-1. The relationship between light sensitivity and HbA1c value was calculated using linear regression analysis.
RESULTS: Total mean sensitivity at 10° for group 1 without DR, group 2 with mild NPDR and control group were 18.67±0.83, 17.98±1.42 and 19.45±0.34 (dB), respectively. There was a significant difference in total mean retinal sensitivity at 10° between the 3 groups (F(2,89)=18.14, p=0.001). A simple linear regression was calculated to predict HbA1c based on retinal sensitivity. A significant regression equation was found (F(1,90)=107.61, p=0.0001, with an R2 of 0.545). The linear regression analysis revealed that there was a 0.64dB decline in mean retinal sensitivity within the central 10° diameter with an increase of 1mmHg of HbA1c.
CONCLUSION: Retinal sensitivity at the central 10° of the macula is affected by changes in HbA1c values.

Matched MeSH terms: Visual Field Tests
Fulltext Factors Affecting Visual Field Outcome Post-Surgery in Sellar Region Tumors: Retrospective Study

Sriram PR, Sellamuthu P, Ghani ARI

Malays J Med Sci, 2017 Dec;24(6):58-67.
PMID: 29379387 DOI: 10.21315/mjms2017.24.6.7

Background: Despite the broad category of differentials for sellar region, most of them present with similar clinical signs and symptoms. Headache and visual disturbance are among the frequently seen as presenting symptom. Visual field (VF) assessment is one of the crucial component of neuroophtalmologic assessment and mean deviation (MD) value from automated perimetry allows quantification of the visual field defect. We formulated a study to look into the factors that affect the visual field outcome after surgery.
Methods: All patients with sellar region tumor who has underwent surgery in Queen Elizabeth Hospital from July 2010 to July 2016 were retrospectively analysed through hospital notes. VF assessment via Humphrey visual assessment for these patient pre and post-surgery were reviewed for MD value.
Results: Eighty four patients were recruited and out of them, 151 eyes were taken into analysis after excluding eyes with missing data. Mean age of patients were 45.4 years with 70.2% of them were male. Visual disturbance is the commonest presenting symptom with mean duration of symptom prior to surgery is 9.7 months. Majority of them were pituitary adenomas (75%) followed by sellar meningioma (19%), craniopharyngioma (4.8%), and rathke cleft cyst (1.2%). 70.9% of patients showed improvement in VF based on MD outcome. Mean MD for pre surgery and post-surgery were -14.0 dB and -12.4 dB, respectively. Univariate analysis reveals younger age, female sex, shorter duration of symptom, pituitary adenoma, transsphenoidal approach, and transcranial approach favours improvement in VF. Multivariate analysis shows only shorter symptom duration, transphenoidal approach, and transcranial approach are significant for favourable VF outcome when other factors adjusted.
Conclusion: Symptom duration and surgical approach were independent factors that affects the visual field after surgery in patients with sellar region tumors.

Matched MeSH terms: Visual Field Tests
Fulltext A Study on the Central Corneal Thickness of Primary Angle Closure and Primary Angle Closure Glaucoma and Its Effect on Visual Field Progression

Tan HK, Ahmad Tajuddin LS, Lee MY, Ismail S, Wan-Hitam WH

Asia Pac J Ophthalmol (Phila), 2015;4(3):161-5.
PMID: 26065503 DOI: 10.1097/APO.0000000000000058

PURPOSE: To determine the mean central corneal thickness (CCT) and the relationship between the CCT and visual field progression in primary angle closure (PAC) and primary angle closure glaucoma (PACG).
DESIGN: A combined cross-sectional and prospective study on PAC and PACG.
METHODS: A total of 35 eyes were included in the study for each group of normal control, PAC, and PACG patients from eye clinics in Kota Bharu, state of Kelantan, Malaysia, from January 2007 to November 2009. The PAC and PACG patients were divided into thin and thick CCT groups. They were followed up for 12 to 18 months for visual field progression assessment with their mean Advanced Glaucoma Intervention Study (AGIS) score.
RESULTS: The CCT was 516.8 ± 26.0 µm for PAC and 509.7 ± 27.4 µm for PACG. Both were significantly thinner compared with the control group with CCT of 540 ± 27.8 µm (P < 0.001). There was a statistically significant increase in the mean AGIS score after 12.9 ± 1.7 months of follow-up in the thin CCT group for PACG (P = 0.002). However, no significant increase in the mean AGIS score was found for the thick CCT group in PACG and for both thin and thick CCT in PAC.
CONCLUSIONS: The PAC and PACG had statistically significant thinner CCT compared with the controls. Thin CCT was associated with visual field progression based on the mean AGIS score in PACG.

Matched MeSH terms: Visual Field Tests
Fulltext Stress and repetitive visual field assessment in glaucoma patients

Tan, Kok-Leong, Fhun, Lai-Chan, Ahmad Tajudin Liza Sharmini, Maizan Yaakub, Chong, Mei-Fong

Journal of Biomedical and Clinical Sciences, 2017;2(2):35-41.
MyJurnal

Glaucoma is a chronic disease that could affect the quality of life and is a potential stressor for patients. Visual field assessment is important in monitoring disease progression among glaucoma patients. Stress could influence the performance of patients in visual field test that may affect the reliability of the test. Our objective in this study was to determine the association between stress score using Depression, Anxiety and Stress Scale (DASS) questionnaire and reliability indices of Humphrey visual field analysis (HFA). A total of 155 primary and secondary glaucoma patients were recruited in the study. Face to face interview using stress component of DASS questionnaire was conducted after automated HFA test. Reliability indices; i.e. fixation loss, false positive, and false negative error, were used to determine the accuracy of HFA result. Only 12 patients (7.7%) were found to have elevated stress score. No significant correlation was found between DASS stress score and the reliability indices of HFA. There was 0.2 folds (95% confidence interval (CI) [-2.35, -0.06], p = 0.039) reduction of fixation loss for every number of HFA done. For every one year increase in age, there was 0.2 folds (95% CI [-0.38, -0.07], p = 0.006) reduction in false positive error in HFA.
Minimal stress may not affect the reliability of HFA assessment. Minimising stress among glaucoma patients is important not only for assessment of visual field but also for improvement of quality of life.

Matched MeSH terms: Visual Field Tests