• Journal of Korean Ophthalmic Optics Society
• /
• v.16 no.2
• /
• pp.167-170
• /
• 2011

Purpose: This study was tried whether expectation of astigmatism from spherical equivalent visual acuity was possible. Methods: For 54 men and women (108 eyes) corrected to emmetropia, average age of 23.3, changes of visual acuity (5m) were measured with an increasing the powers at every ${\pm}$0.25D when the (-) axis of cross cylinder is $180^{\circ}$, $90^{\circ}$, and $45^{\circ}$, respectively. Results: As the power of cross cylinder was increased, visual acuity was decreased. When the powers of cross cylinder were ${\pm}$2.50D ($180^{\circ}$ and $90^{\circ}$) and ${\pm}$2.25D ($45^{\circ}$), visual acuity was 0.05 which is the minimum measurement possible. Conclusions: The diagram on astigmatism dealing with each spherical equivalent visual acuity was able to tabulate.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.10 no.1
• /
• pp.340-348
• /
• 1997

The glaucoma, cataract and causing-blindness-diseases have high clinical importance by their severity of the symptoms and possibility of causing visual loss. Glaucoma is caused by an increase in the intraocular pressure, if severe enough, can cause field loss and eventually complete blindness. In cataract, the general clarity of vision is impaired due to a loss of transparency of the chrystalline lens of the eye. The causing-blindness-diseases can be divided to PokMaeng which cause sudden blindness and ChungMaeng, in which visual acuity is losed gradually. In glaucoma, cataract and causing-blindness-diseases, the visual acuity is affected and the patient may complain blurriness, fatigue of eye, visual field loss deficiency or scintillant feeling, vitreous floaters. In this study, 32 patients who have cataract, glaucoma or other causing-blindness-diseases was treated with oriental medicine or acupuncture from July, l996 to May. 1997, and was followed up by their symptoms and visual acuity. 1. In glaucoma patients, intraocular pressure decreased significantry and the symptoms improved positively. 2. In cataract patients, there was no improvement of visual acuity but $40\%$ of patients found their symptoms improved. 3. In causing-blindness-diseases, $57\%$ of patients reported improvement of their symptoms such as blurriness or fatigue of eye. 4. Through oriental medical treatment, the symptoms of glaucoma, cataract and causing-blindness-diseases can be treated effectively. Therefore oriental management seems to be possible to cure glaucoma, cataract and causing-blindness-diseases.

• Journal of the Korean Society of Safety
• /
• v.35 no.3
• /
• pp.105-115
• /
• 2020

This study compares the difference of fit factors (FF) and visual acuity according to masks and eyeglasses preferences for 54 participants. We the precautions and behaviors of discomfort when wearing masks of eyewear wearers. Contact lens discomfort and priority action of complaints was investigated Glasses fitting factors is Optical Center Height(OH), Vertex Distance(VD) and Pantoscopic Angle(PA). We measured those factors and expressed by the ratio of standard point and change point. Quantitative fit factor was measured by Portacount Pro+ 8038. Also, we selected to 6 exercises among 8 exercises OSHA QNFT (Quantitative Fit testing) protocol to measure the fit factors. The pass/ fail criterion of FF was set at 100. Visual acuity(VA) test chart is developed by Chunsuk Han was used, Descriptive statistics was performed. Descriptive statistics(SAS ver 9.2), it is used geometric means, Wilcoxon analysis(P=0.05) When wearing the mask preferentially, fit factor(FF) was high according to the step of glasses fitting parameter. on the other hand, when the glasses first choice, the visual acuity(VA) was high. there was no significant difference. In the case of fit factor (FF), mask first choice/ glasses first choice is OH (p=0.671/ p=0.332), VD (p=0.602/ p=0.571) and PA (p=0.549/ p=0.607). Visual acuity (VA), mask first choice/ glasses first choice is OH (p=0.753/ p=0.386), VD (p=0.815/ p=0.557) and PA (p=0.856/ p=0.562). The workers of workplace and office chose glasses but occupational health workers and students chose mask. In case of discomforts, it was suggested to remove the mask and tolerate discomforts. The main discomforts and usual action of lens were dryness, hyperemia, foreign body sensation, ophthalmodynia, decreased vision and glasses wearing. Therefore, it is necessary to develop a mask wearing method education program considering glasses fitting and develop a hybrid model that minimizes inconvenience when wearing glasses and a mask at the same time.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.1
• /
• pp.17-22
• /
• 2014

Purpose: We aimed to evaluate reliability of eye exam for visual acuity as a function of distance. Methods: There were 39 patients (78 eyes) who had visual acuity 1.0 or more at 5 meters. We measured refractive power of patients at each distances, 5 meters, 4 meters and 3 meters. Automatic chart (LCD-700, Hyeseong Optic. Co., Korea) used for visual acuity, skiascope (Beta 200, Heine, Germany) and auto refractometer (RK-5, Canon, Japan) used as for objective refraction. Accommodation was examined by minus lens addition methods, and Accommodative lag was examined by grid chart for reading distance. Results: Being compared to 3 meter test, Amount of corrected spherical refractive power decreased by $0.10{\pm}0.38$ D, astigmatism decreased by $0.05{\pm}0.10$ D, and axis of astigmatism rotated toward to temporal by $2.64{\pm}18.75$ degrees for right eyes, by $11.43{\pm}48.55$ degrees for left eyes in case of 5 meter test. Changes of corrected refraction and astigmatism were slightly correlated (r=-0.31, r=-0.29). Conclusions: Because corrected refraction power and amount of astigmatism decreased and axis of astigmatism tends to turn the temporal direction according to exam distance, examination distance of visual acuity should improved as to 5 meters.

• Journal of Korean Neurosurgical Society
• /
• v.49 no.6
• /
• pp.339-344
• /
• 2011

Objective : Pituitary apoplexy is one of the most serious life-threatening complications of pituitary adenoma. The purpose of this study is to investigate the visual outcome after early transsphenoidal surgery for the patients with pituitary apoplexy. Methods : We retrospectively reviewed the 31 patients with pituitary apoplexy who were admitted due to acute visual acuity or field impairment and treated by transsphenoidal surgery. Five patients were excluded because of the decreased conscious level. The visual acuity of each individual eye was evaluated by Snellen's chart Visual fields were also checked using automated perimetry. To compare the visual outcome according to the surgical timing, we divided the patients into 2 groups. The first group, 21 of the patients have been undertaken transsphenoidal approach (TSA) within at least 48 hours after admission. The second group included 8 patients who have been undertaken TSA beyond 48 hours. All patients were monitored at least 12 months after surgery. Results : Patients were 21 males and 8 females (M : F=2.6 : 1) with the mean age of 42.4 years. Among the enrolled 29 patients, 26 patients presented with decreased visual acuity and 23 patients revealed the defective visual field respectively. Postoperatively, improvement in the visual acuity was seen in 15 patients (83.3%) who underwent surgery within the first 48 hours of presentation, as compared to those in whom surgery was delayed beyond 48 hours (n=5; 62.5%) (p=0.014). Improvement in the visual field deficits was observed in 15 (88.2%) of patients who had been operated on within the first 48 hours of presentation, as compared to those in whom surgery was delayed beyond 48 hours (n=3; 50.0%) (p=0.037). Conclusion : This study suggests that rapid transsphenoidal surgery is effective to recover the visual impairment in patients with pituitary apoplexy. If there are associated abnormalities of visual acuity or visual fields in patients with hemorrhagic pituitary apoplexy, early neurosurgical intervention within 48 hours should be also required to recover visual impairment.

• Journal of the Korean Society of Safety
• /
• v.33 no.1
• /
• pp.47-53
• /
• 2018

This study compares the interrelation of fit factor(FF) and visual acuity test by the order of wearing preference between Particulate filtering face piece respirators(PFFR) and glasses for 54 participants. Glasses fitting factors is Optical Center Height(OH), Vertex Distance(VD) and Pantoscopic Angle(PA) or Visual acuity. We measured those factors and expressed by the ratio of standard point and change point. Quantitative fit factor was measured by Portacount Pro+ 8038 and compared the result of preference of wearing order between respirators and glasses. Also, we selected to 6 exercises among 8 exercises OSHA QNFT (Quantitative Fit testing) protocol to measure the fit factors. The pass/ fail criterion of FF was set at 100. Visual acuity test chart is developed by Chunsuk Han was used, Descriptive statistics was performed. Descriptive statistics(SAS ver 9.2), it is used geometric means, Wilcoxon analysis, peason correlation(P=0.05) Fit factor was increased when the respirator was worn before wearing the glasses(p=0.000) and decreased for visual acuity(p=0.000) The negative correlation was showed between OH and Overall fit factor(r=-0.409, p=0.002). Among 54 participants, 11 participants(20.3%) were worn respirator before wearing glasses and 1 participant(1.9%) was worn glasses before wearing respirator. The overall fit test showed the higher level was investigated for the group of participants wearing respirator before wearing glasses in 6 exercises. Also, overall fit factor were increased when participants wore glasses prior to respirator(16.6) to respirator prior to glasses(36.6). Visual acuity were increased when participants wore respirator prior to glasses(93.8) to glasses prior to respirator(106.0). Finally, comparison result of overall fit factor and visual acuity were glasses first choice from mask first choice. The results showed that higher overall fit factor was investigate when the participants wore the respirator prior to glassess at all. The results implied that it is important to maintain the overall fit factor and visual acuity according to the consideration of OH for glasses fitting when worker wore respirator and glasses at the same time.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.2
• /
• pp.261-270
• /
• 2014

Purpose: To study the effect of an artificially induced dioptric blur on acuity and contrast sensitivity using the $Optec^{(R)}$ 6500. Methods: Healthy 31 subjects aged $22.90{\pm}1.92$ (male 16, female 15) who were recruited from university students with 6/6 (20/20) or better corrected visual acuity and normal binocularity. They were measured objective and subjective refraction for full correction and dioptric blur using 0.00 ~ +3.00 D (+0.50 D steps) trial lenses and trial frame. They were measured binocularly visual acuity and contrast sensitivity with the $Optec^{(R)}$ 6500 (Stereo Optical Co., Inc., Chicago, Illinois, USA) under day conditions (photopic condition, $85cd/m^2$). Results: The higher dioptric blur, the less distance visual acuity and decrease rate of visual acuity. The higher dioptric blur, the less contrast sensitivity at all frequencies, and the peak of contrast sensitivity was shifted from middle frequency (6 cpd) to low frequency (1.5 cpd). When the visual acuity was best visual acuity to 0.77, there was the peak point at 6 cpd which was normal contrast sensitivity peak point. Conclusions: If the low refractive error is uncorrected or the refractive error is inappropriate, the contrast sensitivity is decreased and the peak point of contrast sensitivity frequency is shifted abnormally though small uncorrected refractive error. So it will be considered that regular eye test and decision of refractive error correction is important.

• Journal of Korean Neurosurgical Society
• /
• v.42 no.3
• /
• pp.216-219
• /
• 2007

Lymphocytic hypophysitis is a clinically rare disease, and it has been known to be an autoimmune disease which mainly affects pregnant women at the end of gestation or right after delivery. The authors experienced a case of lymphocytic hypophysitis in a 29-year-old pregnant woman with rapid progressing visual disturbance. Sella MRI showed a mass-like lesion of hypophysis and hypertrophy of pituitary stalk with evidences of hypopituitarism. Cesarean section was done and then TSA was performed. The pathologic diagnosis was lymphocytic hypophysitis. After TSA, visual acuity was improved and visual field defect was recovered. She was given thyroid hormone replacement therapy because of transient partial hypopituitarism for 6 months after surgery. One must consider the probability of lymphocytic hypophysitis, if there are alteration of visual acuity and visual field defect which aggravate rapidly during pregnancy due to mass effect, decreased serum hormonal levels shown in hypopituitarism and sella MRI findings of hypertrophy of pituitary stalk and enlargement of pituitary gland.

• Journal of The Korean Ophthalmological Society
• /
• v.54 no.9
• /
• pp.1445-1451
• /
• 2013

Purpose: To report long-term changes in the average retinal nerve fiber layer (RNFL) thickness in 2 patients who had intravitreal bevacizumab (IVB) injection for diabetic papillopathy. Case summary: A 36-year-old patient with diabetes complained of decreased visual acuity (20/200) in the right eye. The fundus examination showed optic disc swelling in both eyes. The average RNFL thickness based on optical coherence tomography (OCT) increased to $278{\mu}m$ and Goldmann perimetry showed nasal visual field defect in the right eye. The IVB was injected into the right eye. Three weeks after the IVB injection, RNFL thickness decreased to $135{\mu}m$ and visual acuity improved to 20/25 in the right eye. However, RNFL thickness increased from 126 to $207{\mu}m$ and visual acuity decreased to 20/32 in the left eye. Thus, IVB was injected into the left eye. In week 3, RNFL thickness decreased to $147{\mu}m$ and visual acuity improved to 20/20 in the left eye. At 12 months after IVB injection, RNFL thickness was $87{\mu}m$ in the right eye and $109{\mu}m$ in the left eye. A 57-year-old patient with diabetes complained of decreased visual acuity (20/200) and showed optic disc swelling in the right eye. The average RNFL thickness increased to $252{\mu}m$ and Goldmann perimetry showed an enlarged blind spot in the right eye. IVB was injected into the right eye. After 3 weeks, RNFL thickness decreased to $136{\mu}m$ and visual acuity improved to 20/70 in the right eye. Six months after IVB injection, RNFL thickness was $83{\mu}m$ in the right eye. Conclusions: Visual acuity progressively improved within 3 weeks and RNFL thickness measured by spectral domain OCT showed progressive thickness reduction in 2 cases of diabetic papillopathy patients who had IVB injections.

• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.3
• /
• pp.355-362
• /
• 2015

Purpose: To investigate the effects of the transmittance of diffusive blurson visual acuity and contrast sensitivity. Methods: Visual acuity and contrast sensitivity were measured by using Optec$^{(R)}$ 6500 in Healthy 30 subjects aged $22.83{\pm}0.50$ (male 13, female 17) who were recruited from university students. Cataract simulator was used as a tool for diffusive blur. Visual acuity and contrast sensitivity were measured with varying the transmittance of diffusive blur in order to simulate progression of cataract and concentration in fog. Results: Visual acuity was reduced proportionally with decreasing the transmittance of the diffusive blur as follows: $VA(T)=1.84{\times}10^{-2}T-0.645$. Contrast sensitivity was decreased in all spatial frequencies. Contrast sensitivity in a high spatial frequency band was a greater effect and was off the normal range of contrast sensitivity. The peak of contrast sensitivity was moved in the direction to low frequency. From an intersection point of contrast sensitivity function, we could calculated the transmittance of the diffusive blur being off the normal range and the shift to peak spatial frequency. The peak of contrast sensitivity function was observed to move from 6 to 3 cpd at transmittance of about 78.70%, the contrast sensitivities for all frequencies at transmittance of about 69.71% were deviated from the normal range. Conclusions: The transmittance of diffusive blur causes a reduction in visual acuity and contrast sensitivity, a deviation of normal range of contrast sensitivity, and a shift of peak contrast sensitivity. Therefore the more attention is required when suffering from cataracts or driving in fog.