A Survey on Contact Lens Care in Young Adolescent Student

PURPOSE: The present study was conducted to gather valid data for promoting public eye health among adolescent contact lens wearers by investigating the current practices of contact lenses wearers. METHODS: A questionnaire regarding use and care of contact lenses was distributed to middle and high school students. A total of 920 students (472 males, 448 females) were enrolled and the purpose of the study was explained to the students. RESULTS: Among all student, 49% had myopia (male 44%, female 54%) and 12% hyperopia (male 12%, female 13%). In addition, 70% of the subjects chose to wear glasses for vision correction, 27% (male 4%, female 50%) reported they have worn contact lenses and 64% of those were soft contact lenses. The age for starting contact lenses was between 14-16 years of age (63%). Most students (95%) purchased their contact lenses from an optical store. Many (89%) cleaned the contact lenses with cleaning solution on a daily basis, however, only 25% of the students received instructions on how to clean the lens properly. Common complaints associated with use in descending order were hyperemia (31%), foreign body sensation (19%), tearing (16%), pruritis (13%), and keratitis (9%). The subjects reported that the main cause of complications was due to the users' lens handling (93%). CONCLUSIONS: The present study findings showed many adolescents have misleading knowledge regarding use of contact lenses. There is a need for better education of young contact lens users regarding the contact lens care.

Change in tooth length and angulation on panoramic radiographs taken at different labiolingual and buccolingual inclinations / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to examine how the mesio-distal angulation and the length of each tooth changes on panoramic radiograph at different bucco-lingual inclinations. METHODS: After constructing an acrylic model based on the mean arch of 30 adults with normal occlusion, the wire was placed in the center of the teeth on the acrylic model. First, the wire was implanted in normal angulation and inclination and a panoramic radiograph taken. After changing the inclination from I-15 degrees to I+15 degrees by 5 degrees a panoramic radiograph was taken again and the mesio-distal angle and wire length on the panoramic radiograph were assessed. RESULTS: When the wire was implanted at the normal angulation and inclination, the length measured in the panoramic radiograph was magnified 111 ~ 117% from the original length in the anterior region and 121 ~ 125% in the posterior region. Only the central and lateral incisors showed significant length differences when the inclination was changed from I-15 degrees to I+15 degrees at fixed angulation. When the inclination was changed from I-15 degrees to I+15 degrees, the angulation of most teeth on panoramic radiograph appeared to be more disto-angulated than in reality, and the lateral incisor and canine showed the largest difference. Only I-15 degrees, I+15 degrees groups of premolars and I+15 degrees group of molars showed more mesio-angulation than in reality. As the labio(bucco)lingual inclination of all teeth were decreased, tooth angulation in the panoramic radiograph appeared to be more disto-angulated. CONCLUSION: The labio-liugual inclination of teeth should be considered because it affects panoramic image of teeth, such as length of incisors and angulation of other teeth.

A Case of Surgical Repair For Convergent Strabismus Fixus with Bilateral Abducens Nerve Palsy

PURPOSE: We report a case in which a convergent strabismus fixus due to head trauma-induced bilateral abducens nerve palsy was successfully corrected. METHODS: A 45-year-old male patient who had bilateral,convergent strabismus fixus and limited eye movement because of bilateral abducens nerve palsy. A year previously, the patient had experienced a skull fracture and right facial nerve palsy caused by a traffic accident. At that time, the forced duction test revealed severe restriction of both eyes. The forced duction test still showed resistance after the right medial rectus muscle was disinserted. We made a conjunctival incision on the lateral canthal area and resected the right lateral rectus muscle. Then we performed lateral canthotomy, and fixed the lateral rectus muscle to the periosteum of the lateral orbital rim. When the left medial rectus muscle was disinserted, there was no resistance on the forced duction test. We then addressed the medial rectus muscle recession, superior and inferior rectus muscle transposition to the lateral rectus. RESULTS: Two years after the procedure, bilateral convergent strabismus fixus did not recur, even though right eyeball movement was impossible. Patient appeared an orthophoria at the primary position, and the cosmetic rersult was satisfactory.

Epidemiologic Studies of Keratoplasty in Korea

PURPOSE: To report an epidemiologic study of keratoplasty in which we analyze basic data of corneal transplants and corneal donations in Korea. METHODS: From June 2004 through October 2004, questionnaires were distributed to 25 hospitals. The questionnaires were about the characteristics of patients registered in eye banks for keratoplasty from May 2001 to April 2003, and about the results of keratoplasties performed from May 2002 to April 2003. RESULTS: The leading corneal diseases in patients registered for keratoplasty were infectious keratitis (22.0%), trauma (21.0%), and pseudophakic and aphakic bullous keratopathy (13.8%), in that order. The leading indications in corneal recipients were: trauma (15.5%), pseudophakic and aphakic bullous keratopathy (13.7%), and infectious keratitis (10.7%), in that order. In 233 cases of keratoplasties, penetrating keratoplasty was performed in 229 cases (98.3%) and lamellar keratoplasty was performed in 4 cases (1.7%). The most common combined surgery was cataract extraction. Common causes of graft failure were rejection of donor cornea and infection. Imported donor corneas were used in sixty-one cases (26.2%) among the 233 total keratoplasties. CONCLUSIONS: We constructed an epidemiologic data base of patients registered for keratoplasty, corneal donation, and the results of keratoplasties throughout Korea.

Epidemiologic Studies of Keratoplasty in Korea

PURPOSE: To report an epidemiologic study of keratoplasty in which we analyze basic data of corneal transplants and corneal donations in Korea. METHODS: From June 2004 through October 2004, questionnaires were distributed to 25 hospitals. The questionnaires were about the characteristics of patients registered in eye banks for keratoplasty from May 2001 to April 2003, and about the results of keratoplasties performed from May 2002 to April 2003. RESULTS: The leading corneal diseases in patients registered for keratoplasty were infectious keratitis (22.0%), trauma (21.0%), and pseudophakic and aphakic bullous keratopathy (13.8%), in that order. The leading indications in corneal recipients were: trauma (15.5%), pseudophakic and aphakic bullous keratopathy (13.7%), and infectious keratitis (10.7%), in that order. In 233 cases of keratoplasties, penetrating keratoplasty was performed in 229 cases (98.3%) and lamellar keratoplasty was performed in 4 cases (1.7%). The most common combined surgery was cataract extraction. Common causes of graft failure were rejection of donor cornea and infection. Imported donor corneas were used in sixty-one cases (26.2%) among the 233 total keratoplasties. CONCLUSIONS: We constructed an epidemiologic data base of patients registered for keratoplasty, corneal donation, and the results of keratoplasties throughout Korea.

Silicone Intubation and Postoperative Mitomycin Application for Partial Nasolacrimal Duct Obstruction in Adults

PURPOSE: This study nasolacrimal duct (NLD) stenosis in adult, evaluated the clinical results of treatment with topical 0.04% mitomycin C (MMC) eyedrops after silicone tube intubation. METHODS: Prospectively, we analysed the clinical results from 29 eyes of 25 adult patients with epiphora due to NLD stenosis who underwent this procedure. RESULTS: The mean follow-up periods was 9.3 months. Twenty-two eyes (76%) showed no epiphora and complete passing into the cavity by lacrimal irrigation. Four eyes (13.7%) showed intermittent epiphora but improvement relative to preoperative state. Three eyes (10.3%) showed persistent epiphora and no improvement. In total, 26 eyes (89%) showed improvement of symptoms. Complications were silicone tube prolapse in 5 eyes (17.2%) and dacryocystitis in 2 (6.9%) CONCLUSIONS: Silicone tube intubation with topical MMC eyedrops for treatment of patients with tearing due to NLD stenosis is effective, safe and easy. This technique can be tried before DCR if the surgeon has a thorough of nasal cavity anatomy and probing.

A Study on the Location of Corneal Thinnest Point and Corneal Thickness in Midperiphery

PURPOSE: To evaluate the association with corneal thickness and corneal thinnest point using Orbscan topography. METHODS: One hundred and four eyes of the 52 normal subjects who were investigated using an Orbscan topography, were devided into following two groups ; one was inferonasal group which has the thinnest point in inferonasal quadrant(23 eyes, 22.1%), and the other was inferotemporal group which has the thinnest point in inferotemporal quadrant. (79 eyes, 76%) Among them, age-matched 30 eyes were randomly selected. The corneal thickness of two groups were measured at eight meridian of each point distant 1.0, 1.5, 2.0, 2.5, 3.0mm from corneal center. The thickest point and the thinnest point of cornea in two groups were compared and analysed. RESULTS: The thickest point of cornea in two groups was located in the superior portion. The thinnest quadrant was located in the inferonasal portion for inferonasal group and in the inferotemporal portion for inferotemporal group. CONCLUSIONS: The quadrant where the thinnest quadrant existed had the thinnest corneal thickness in comparing with any other quadrant.

A Study on Central Corneal Pachymetry Maps with Orbscan Corneal Pachymetry System in Myopic Eyes

PURPOSE: To evaluate central corneal thickness and pachymetry maps in myopic eyes. METHODS: 104 eyes of 52 myopic patients were investigated using the Orbscan (Orbtek, Inc., USA). The pachymetry maps were designated as round, oval, decentred round, and decentred oval. Corneal thickness was evaluated at the central, eight-paracentral, and the thinnest sites on each of the corneas. We studied difference of corneal thickness under sex and myopic degree. And got the symmetry of the cornea under location of the thinnest sites. RESULTS: Superior cornea had the greatest average thickness (605.5+/-35.3 mu m). Average central corneal thickness (+/-SD) was 552.2 (+/-34.9) mu m. All corneas had the thinnest sites on 0.86 mm from the visual axis and most of all inferotemporal area (76.0%). There was no significant difference of corneal thickness in sex and myopic degree. Average thickness of the thinnest sites was 544.2 (+/-35.6) mu m and significantly thinner than center. 61.5% of the persons had symmetrically located thinnest corneal sites and most of all (57.7%) had temporal side symmetry. In the pachymetry maps, oval pattern was 47.1% of 104 eyes, andround, decentred oval, decentred round were observed in 43.3%, 5.8%, and 3.8% of eyes, respectively. CONCLUSIONS: Of all myopic eyes evaluated in this study, the thinnest sites were on average 0.86 mm from the visual axis. And oval type was the most common pachymetry map pattern.

The Effect of Upper and Lower Lid Blepharoplasty for Patients with Corneal Problems due to Medial Upper and Lower Eyelash

PURPOSE: Epicanthal folds and epiblepharon which often develop in oriental children are congenital anomalies of eyelids. These may need surgical correction because corneal irritation may develop by medial upper and lower eyelash besides cosmetic problems. V-Y plasty and Mustarde's method are standards for correction of epicanthal folds, but not usually performed because of cosmetic scar formation. METHODS: This study included 26 patients, 52 eyes (19 females, 38 eyes; 7 males, 14 eyes) with corneal irritation due to medial upper and lower eyelash. We performed upper and lower lid blepharoplasty simultaneously and analyzed their results and complications through medical records. RESULTS: Epiblepharon associated with epicanthus tarsalis was found in 22 patients, 22 eyes, epicanthus palpebralis in 4 patients, 8 eyes. At the time of surgery mean age was 7 years old (3.7~10.3 years old). During the follow-up more than 6 months, double fold asymmetry was found in 1 patient, double fold loosening in 1 patient, 2 eyes, lower eyelid undercorrection in 2 patients, 3 eyes. CONCLUSIONS: These findings suggest that simultaneous upper and lower lid blepharoplasty for patients with corneal problems due to medial upper and lower eyelash is more unsatisfactory in the cosmetic result than standard method, but has advantage of less scarring, and thought to be a good method to relieve corneal irritation.

Classification of Anterior and Posterior Elevation and Axial Curvature Maps of Cornea using the Orbscan in Myopic Eyes

PURPOSE: To evaluate anterior and posterior elevation maps and axial curvature maps in myopic eyes. METHODS: One hundred and four eyes of 52 myopic patients were investigated using the Orbscan (Orbtek, Inc., USA). The anterior and posterior maps were defined as PAR CTS. And the axial curvature maps were designated as Bogan's classification. We got the distribution and astigmatism power of every map patterns, and the similarity of both eyes under map patterns. RESULTS: Island (37.5%) was the most common anterior elevation pattern, and regular ridge (36.5%) pattern was the most common in posterior corneal surface. There was more significant astigmatism in regular ridge and irregular ridge patterns than incomplete ridge in anterior corneal surface. And astigmatism was more significant on regular ridge than incomplete ridge in posterior corneal surfaces. There was no significant difference between topography of anterior and posterior corneal surface. In axial curvature maps, symmetric bow tie was 35.6% of 104 eyes, and irregular, oval, asymmetric bow tie, round were observed in 27.9%, 18.3%, 13.5%, 4.8%, respectively. Mean astigmatism was significantly high on symmetric bow tie than round. Similarity of both eyes was 50% in anterior elevation maps, 26.3% in posterior corneal surface, and 59.6% in axial curvature maps. CONCLUSIONS: Anterior and posterior elevation and axial power corneal topography maps using the Orbscan were useful for evaluation of normal cornea and preoperative and postoperative corneal status at refractive surgery. But, there were many irregular types and low similarity of both eyes relatively.

Epidemiology of Infectious Keratitis(II): A Multi-center Study

To identify risk factors and causative organisms, and to evaluate clinical manifestations, methods and results of treatment in infectious keratitis, an epidemiological study was performed prospectively under the identical protocol from April 1995 to March 2000.Logistic regression analysis was used to evaluate possible risk factors. The 1474 cases of infectious keratitis reported from 22 hospitals were studied. Five hundred forty-four organisms(442 bacteria, 82 fungi, 20 A c a n t h a m o e b a)were detected in 1320 eyes with infectious keratitis excluding 154 herpetic keratitis. The Pseudomonas aeruginosa was the most common organism in bacterial keratitis, and Fusariumspp. was the major isolate in fungal keratitis. Contact lens wear and occupation(industry, forester, miner, fisherman)were the risk factors for bacterial keratitis. Risk factors in fungal keratitis were fifth decade of age, farmer, and systemic diseases(diabetes mellitus etc.). Risk factors in herpetic keratitis were male and occupation(office worker, service, student, housewife). Risk factors in Acanthamoeba keratitis was contact lens wear.

Corneal Thickness Variation and Consistency According to Daytime

To analyze the normal adult corneal thickness, we used the Orbscan(Orbtek, Inc.)to measure 50 volunteer subjects. The reproducibility of the pachymetry, the daytime variation of corneal thickness and the consistency of thickness across days were analyzed. All 50 subjects were measured, taken each at 8:00, 9:30, 11:00, 13:00, 14:30, and 16:00. The corneal thickness was taken at the center and 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm and 3.5 mm away from the center. Also measurements were made 3 consecutive days at the center, 2.0 mm and 3.5 mm away from the center. Repeatability of corneal thickness was highly reliable(Guttman split-half point:0.9972 and 0.9961, respectively). The average distance difference was 10 micrometer at the center and 23 micrometer at 3.5 mm away from the center. The corneal thickness did show a diurnal pattern during the day but was stable when measured across days. No significant difference when measuring on the same hour on another day was shown the corneal thickness to be consistent.

Comparison of Corneal Thickness Measurements with the Orbscan and Ultrasonic Pachymetry

To verify the accuracy and reproducibility of corneal thickness measurements obtained with Orbscan (Orbtek, Inc., Salt Lake City, USA), the measurements were compared with those taken with an ultrasound pachymeter (Omega Compuscan, Storz). Central corneal thickness was measured by each method in 100 eyes of 50healthy subjects. The averages by the two methods were compared. One examiner took the measurements twice by each method in 20 eyes of 10 subjects, and intraexaminer reproducibility was evaluated. Two examiners measured the thickness in 20 eyes of 10 subjects and interexaminer reproducibility was assessed. The average corneal thickness was 550.27+/-3.56 micrometer in the Orbscan measurements and 526.62+/-3.70 micrometer in the ultrasound pachymetry: There was a statistically significant difference between the two methods. Significant difference was noticed but this showed a constant corresponding correlation with the Orbscan showing a 4.4%lower average. The intraexaminer and interexaminer reproducibility showed high reliability(Guttman split-half point<0.99). The Orbscan pachymetry is a highly reliable method and may be widely used in clinical practice.

A Study on Microcirculation Time Including Retinal Periphery in Diabetic Retinopathy using the Fluorescein Angiography

On video fluorescein angiogram, it is known that arm-to-retinal circulation(ART)influences retinal macrocirculation and arterio-venous passage time(AVP)influences microcirculation.In diabetic retinopathy(DR), midperiphery involved earlier than posterior pole.However, there has been no study on the circulation of the entire retinal circulation including the peripheral retina. The authors conducted a prospective study by performing fluorescein angiography on 19 controls and 19 DR patients in order to measure the ART, AVP and venous filling time(VFT). The VFT correspond to the circulation of the peripheral retina. In the DR group, the retina circulation time was compared with the existence of proliferative diabetic retinopathy(PDR), distribution of nonperfusion area and beading vessels. There was no significant difference between diabetic group and the control group in the ART.AVP was 1.8+/-0.7sec in the control group and 2.5+/0.7sec(p=0.04)in the DR group and venous filling time was 6.4+/-2.4sec and 8.9+/-1.5sec(p=0.006)respectively. Patients with PDR showed prolongation only in VFT compared to patients with non-proliferative diabetic retinopathy(NPDR). In addition, patients presenting with nonperfusion areas and beading of vessels showed longer prolongation of VFT than of AVP. In conclusion, the VFT is delayed in DR compared to control group and in PDR compared to NPDR. The VFT can be utilized as an indicator of DR to measure the retinal circulation including the peripheral retina.

Silicone Tube Frontalis Sling For the Correction of Blepharoptosis

No Abstract Available.

Epidemiology of Fungal Keratitis in Korea: A Multi-center Study

Fungal keratitis, one of devastating microbial keratitis, is difficult to diagnose and treat successfully. The authors performed prospectively an epidemiological study in Korea to identify the risk factors and to evaluate clinical manifestations, methods and results of treatment in fungal keratitis under the identical protocol from April 1995 to September 1999. Logistic regression analysis was used to evaluate possible risk factors. Sixty eight cases of fungal keratitis, which were identified by culture with corneal scraping or corneal biopsy and reported in 22 hospitals, were studied. The major causative organisms were Fusarium spp.(20 cases), Aspergillus spp.(17 cases), and Candida spp.(11 cases). The principal risk factors of fungal keratitis identified in this study were farmer, use of long-standing topical corticosteroids, and diabetes mellitus. Old age and corneal trauma with vegetable matters were the associated factors in fungal keratitis. Further evaluation of the risk factors and the establishment of the prevention in fungal keratitis are required.

Reproducibility of Perifoveal Fluorescent Dots Velocity Measurements on Fluorescein Angiography with a Scanning Laser Ophthalmoscope

To evaluate the reproducibility in measuring the velocities of perifoveal hyperfluorescent dots, we analyzed fluorescein angiographs of 24 eyes[24 patients]which had central serous retinopathy. Fluorescein angiography was performed with a scanning laser ophthalmoscope[SLO, Rodenstock, Mnchen, Germany]Distances between 5 moving hyperfluorescent dots in a perifoveal capillary were measured at each consecutive frame[interval 1/30 sec]. And then velocities of 5 fluorescent dots were measured with image analysis program by converting the distances to real retinal size using the Littmann's curve in 20 eyes. In the other 4 eyes, the velocities between 5 fluorescent dots of each 2 to 4 capillaries were measured. Perifoveal capillary mean blood flow velocity and standard deviation were 2.08 +/-0.36 mm/sec, and mean coefficient of variation of the velocities measured in a vessel of one patient was 12.58%. However, reliability of the velocities of 2 to 4 capillaries on the 4 eyes was relatively low. In conclusion, the measurement of velocities between perifoveal fluorescent dots with scanning laser ophthalmoscope may be a reproducible method for a perifoveal capillary. However, reliability of measuring velocities was not sufficient enough to use the velocity of one perifoveal capillary as macular blood flow.

Hydrox yapatite Implantation with Scleral Patch Graft in Eviseration

When inserting an orbital implant, evisceration allows suitable movement of the eyeball making it a better method cosmetically than enucleation; performing hydroxyapatite implantation after evisceration preserving the cornea sometimes causes the complication of cornea melting. To reduce complications after evisceration and hydroxyapatite implantation,scleral patch graft with corneal excision was performed in 15 eyes of 15 patients. In all 15 eyes, 20 mm-sized hydroxyapatite implants were inserted. Fourteen eyesshowed no complications, but in one eye scleral suture was exposed and 2months later the implant was exposed around that area. Also, there developed conjunctival wound dehiscence and exposure of the central portion of the scleral graft in two eyes. But the exposed sclera was fibrovascularized by the surrounding conjunctival tissue and did not lead to exposure of the implant. This study suggests that when performing evisceration and hydroxyapatite implantation, scleral pach graft with cornea excision is helpful in reducing the incidence of exposure of hydroxyapatite implant.

The Role of Scalp Flap Retraction during Cerebral Aneurysm Surgery as a Potential Cause of Visual Deficits

OBJECTIVE: We recently reported six patients with unilateral visual loss that developed immediately after cerebral aneurysm surgery. This was found to be due to retinal ischemia. PATIENTS AND METHODS: To investigate whether or not this rare occurrence results from focal compression on the ipsilateral globe due to a scalp flap retraction, the authors checked changes of orbital pressure indirectly before and after the flap retraction in seven consecutive aneurysm patients and repeated the measurement in six other patients protected with an eye shield. In addition we have used an eye protector during aneurysm surgery over a next three-year period to determine whether or not an eye shield can prevent this problem. RESULTS: The authors confirmed elevation of indirect intraorbital pressure whenever the flap was retracted, but there was no pressure elevation in the study using an eye shield. In parallel we have not experienced any visual complications since this maneuver. CONCLUSIONS: We think that inadvertent pressure placed on the eyeball with a retracted scalp flap might provoke intraocular and/or retinal ischemia resulting in visual failure after intracranial aneurysm surgery in patients with any conditions that induce marginally ischemic retina.

The Effect of the Changes in Central Corneal Thickness and Curvature on Measurement of Intraocular Pressure after LASIK

The measurement of intraocular pressure (IOP) is influenced by the parameters of corneal thickness, corneal curvature, and corneal astigmatism. LASIK changes these parameters and may influence measurements of IOP. IOPs of 62 eyes were analysed before LASIK and 6 months after LASIK and the correlation coefficient between IOP and corneal thickness & corneal curvature was determined. Preoperative and postoperative IOP after 6months follow-up was 13.03 +/- 3.26 mmHg, 9.26 +/-1.69 mmHg respectively. Postoperative IOP was significantly decreased as compared to preoperative one. There was a tendency that showed the low IOP was related to the decrease of corneal thickness & corneal curvature. Each correlation coefficient was r=0.563, r=0.646 respectively but the coefficient`s influence was not determinable. The decrease of corneal thickness and curvature showed a constant relation to the lowered IOP, therefore it should be taken in account in the patient evaluation.