Ten-year Results after Conventional Corneal Cross-linking in Korean Patients with Progressive Keratoconus

Purpose@#To evaluate the long-term effects of conventional corneal cross-linking in patients with progressive keratoconus. @*Methods@#A total of 18 eyes of 9 patients diagnosed with keratoconus were analyzed retrospectively. One eye was diagnosed with progressive keratoconus and conventional corneal crosslinking was performed. The other eye was classified as non-progressive and remained untreated. All patients were assessed with best corrected visual acuity (BCVA), maximum keratometry (Kmax), mean keratometry (Kmean), corneal astigmatism, and corneal thickness. Clinical data were collected before the procedure and at 1, 3, 6 months and 1 to 10 years after the procedure. @*Results@#The BCVA significantly improved from 0.63 ± 0.18 logarithm of the minimum angle of resolution (logMAR) to 0.46 ± 0.25 logMAR at 10 years after conventional corneal crosslinking (p = 0.027). The Kmax and Kmean decreased from 65.90 ± 9.43 D and 52.82 ± 5.16 D to 62.83 ± 8.16 D and 51.52 ± 5.18 D, respectively (p = 0.021, p = 0.028, respectively). Corneal astigmatism decreased from 6.97 ± 2.21 D to 5.53 ± 1.64 D (p = 0.008). The thinnest corneal thickness decreased from 435.11 ± 53.37 μm to 369.22 ± 64.00 μm 1 month after the procedure (p = 0.008), and gradually improved over time. At 10 years, the thinnest corneal thickness increased to 410.11 ± 61.32 μm (p = 0.097). In the untreated eyes, the mean keratometry significantly increased after 4 years of follow-up, but other factors did not change significantly. Although corneal opacity persisted for up to 10 years in 3 eyes of the treatment group, there was no significant difference of BCVA compared to the treated eyes without corneal opacity (p = 0.714). @*Conclusions@#In patients with progressive keratoconus, conventional corneal crosslinking is a safe and effective procedure that suppresses long-term progression.

Bilateral Calcific Band Keratopathy Treated with Dipotassium Edetic Acid

Purpose@#To report a case of bilateral calcific band keratopathy treated with dipotassium edetic acid (EDTA) in a blood collection tube, an approach that has not been used previously in the Republic of Korea.Case summary: A 77-year-old male patient, with a history of diabetes and hypertension, presented with decreased vision in both eyes that had begun 1 year prior. Five years prior, the patient had undergone cataract surgery in the right eye and had received a diagnosis of prostate cancer for which he was currently under observation without surgical treatment. At the initial eye examination, his best-corrected visual acuity was 0.15 in the right eye and 0.1 in the left eye. Calcium deposition was observed in the center of the cornea by slit-lamp examination, resulting in a diagnosis of band keratopathy. We proceeded to dissolve the dipotassium EDTA coated on a blood collection tube with distilled water. Using the dissolved dipotassium EDTA, we peeled off the corneal epithelium under local anesthesia to remove the calcium deposition. One week after surgery, the visual acuity of both eyes improved to 0.6, and no recurrence or complications occurred for 7 months. @*Conclusions@#As a new treatment for band keratopathy, we discovered that dipotassium EDTA is more convenient to obtain than the conventional disodium EDTA. We expect that dipotassium EDTA will be widely used in the treatment of band keratopathy.

Analyses of Corneal Morphology of Patients with Obstructive Sleep Apnea

Purpose@#To analyze the relationship between corneal morphological factors and polysomnographic factors in patients with obstructive sleep apnea (OSA). @*Methods@#In all, 22 eyes of 22 patients with OSA were analyzed retrospectively under specular microscopy. The central corneal thickness (CCT), endothelial cell density (ECD), hexagonal cell percentage, and cell variation coefficient were measured using specular microscopy, and polysomnographic factors including the apnea-hypopnea index (AHI), respiratory disturbance index (RDI), oxygen desaturation index, and lowest O2 saturation were compared and analyzed between the OSA group and a control group consisting of 32 subjects. Additionally, we examined the statistical correlation between retinal nerve fiber layer (RNFL) thickness and the polysomnographic factors for the 12 OSA patients in which the RNFL thickness was measured. @*Results@#The mean CCT and mean ECD were significantly lower in the OSA group than in controls (p = 0.033, p = 0.021, respectively). As the severity of OSA worsened, a significant negative correlation developed, such that the CCT decreased as the AHI and RDI increased (r = -0.519, p = 0.013 and r = -0.542, p = 0.009, respectively); in addition, the ECD decreased as the RDI increased (r = -0.454, p = 0.034). As OSA progressed, the nasal RNFL thickness decreased with the lowest O2 saturation (r = 0.703, p = 0.011). @*Conclusions@#CCT and ECD were significantly lower in OSA patients than in controls and there was a significant correlation between corneal morphological factors and polysomnographic factors. Due to the possibility of hypoxia and various ophthalmic clinical diseases associated with OSA, close observation of ophthalmic abnormalities in OSA patients is required.

Bilateral Calcific Band Keratopathy Treated with Dipotassium Edetic Acid

Purpose@#To report a case of bilateral calcific band keratopathy treated with dipotassium edetic acid (EDTA) in a blood collection tube, an approach that has not been used previously in the Republic of Korea.Case summary: A 77-year-old male patient, with a history of diabetes and hypertension, presented with decreased vision in both eyes that had begun 1 year prior. Five years prior, the patient had undergone cataract surgery in the right eye and had received a diagnosis of prostate cancer for which he was currently under observation without surgical treatment. At the initial eye examination, his best-corrected visual acuity was 0.15 in the right eye and 0.1 in the left eye. Calcium deposition was observed in the center of the cornea by slit-lamp examination, resulting in a diagnosis of band keratopathy. We proceeded to dissolve the dipotassium EDTA coated on a blood collection tube with distilled water. Using the dissolved dipotassium EDTA, we peeled off the corneal epithelium under local anesthesia to remove the calcium deposition. One week after surgery, the visual acuity of both eyes improved to 0.6, and no recurrence or complications occurred for 7 months. @*Conclusions@#As a new treatment for band keratopathy, we discovered that dipotassium EDTA is more convenient to obtain than the conventional disodium EDTA. We expect that dipotassium EDTA will be widely used in the treatment of band keratopathy.

Analyses of Corneal Morphology of Patients with Obstructive Sleep Apnea

Purpose@#To analyze the relationship between corneal morphological factors and polysomnographic factors in patients with obstructive sleep apnea (OSA). @*Methods@#In all, 22 eyes of 22 patients with OSA were analyzed retrospectively under specular microscopy. The central corneal thickness (CCT), endothelial cell density (ECD), hexagonal cell percentage, and cell variation coefficient were measured using specular microscopy, and polysomnographic factors including the apnea-hypopnea index (AHI), respiratory disturbance index (RDI), oxygen desaturation index, and lowest O2 saturation were compared and analyzed between the OSA group and a control group consisting of 32 subjects. Additionally, we examined the statistical correlation between retinal nerve fiber layer (RNFL) thickness and the polysomnographic factors for the 12 OSA patients in which the RNFL thickness was measured. @*Results@#The mean CCT and mean ECD were significantly lower in the OSA group than in controls (p = 0.033, p = 0.021, respectively). As the severity of OSA worsened, a significant negative correlation developed, such that the CCT decreased as the AHI and RDI increased (r = -0.519, p = 0.013 and r = -0.542, p = 0.009, respectively); in addition, the ECD decreased as the RDI increased (r = -0.454, p = 0.034). As OSA progressed, the nasal RNFL thickness decreased with the lowest O2 saturation (r = 0.703, p = 0.011). @*Conclusions@#CCT and ECD were significantly lower in OSA patients than in controls and there was a significant correlation between corneal morphological factors and polysomnographic factors. Due to the possibility of hypoxia and various ophthalmic clinical diseases associated with OSA, close observation of ophthalmic abnormalities in OSA patients is required.

Two Cases of Oculopharyngeal Muscular Dystrophy in Brothers with Ptosis and Eye Movement Disorder

Purpose@#To report two cases of early onset oculopharyngeal muscular dystrophy, which were suspected to be chronic progressive external ophthalmoplegia.Case summary: Case 1, a 15-year-old male and Case 2, a 13-year-old male brother, visited the clinic with persistent diplopia 6 years prior. The older brother’s best-corrected visual acuity was 0.6 in both eyes and showed an exodeviation of 25 prism diopters. Bilateral ptosis was observed with ocular muscle movement limitations in all directions, and bilateral macular edema was found on fundus examinations. The younger brother had a best-corrected visual acuity of 1.0 in both eyes and showed exodeviation of 45 prism diopters. Bilateral ptosis and ocular muscle movement limitations were also observed. Both patients were suspected to have chronic progressive external ophthalmoplegia and were referred to a neurologist for a neurological examination and muscle biopsy. The muscle biopsies showed that both patients were diagnosed with oculopharyngeal muscular dystrophy. @*Conclusions@#It is important, initially, to report a case of early onset oculopharyngeal muscular dystrophy that has eyelid and eye movement symptoms, but no other typical symptoms.

Acute Myopic Shift and Change in Anterior Chamber Depth after Intake of Zonisamide

Purpose@#To report a case of acute myopic change and anterior chamber depth decrease induced by zonisamide, which is an antiepileptic drug.Case summary: A 40-year-old male with no ophthalmologic history, who was admitted to the neurology department through the emergency center for evaluation and treatment of frontal lobe epilepsy, was referred to the ophthalmology department due to a visual disturbance that occurred while the patient was being treated with 100 mg of zonisamide during hospitalization. Corrected visual acuities with the patient’s own glasses were 0.3 in both eyes, with intraocular pressure of 16 and 17 mmHg in the right and left eye, respectively. Automated refraction revealed a bilateral myopic change of -1.25 diopters (D) in the right eye and -1.00 D in the left eye, and the anterior chambers in both eyes were shallow under slit-lamp examination. As we assumed these symptoms were related to the intake of zonisamide, we immediately instructed the patient to discontinue the drug. At 3 days after discontinuing the drug, his myopia improved, and corrected visual acuities with the previous glasses increased to 1.0 in both eyes. @*Conclusions@#Zonisamide is a sulfonamide anticonvulsant that may cause acute myopic shift and a reduction in the anterior chamber depth. Therefore, physicians must consider the possibility of these complications occurring, when diagnosing a sudden blurring of vision in patients who are taking sulfonamide medications.

Acute Myopic Shift and Change in Anterior Chamber Depth after Intake of Zonisamide

Purpose@#To report a case of acute myopic change and anterior chamber depth decrease induced by zonisamide, which is an antiepileptic drug.Case summary: A 40-year-old male with no ophthalmologic history, who was admitted to the neurology department through the emergency center for evaluation and treatment of frontal lobe epilepsy, was referred to the ophthalmology department due to a visual disturbance that occurred while the patient was being treated with 100 mg of zonisamide during hospitalization. Corrected visual acuities with the patient’s own glasses were 0.3 in both eyes, with intraocular pressure of 16 and 17 mmHg in the right and left eye, respectively. Automated refraction revealed a bilateral myopic change of -1.25 diopters (D) in the right eye and -1.00 D in the left eye, and the anterior chambers in both eyes were shallow under slit-lamp examination. As we assumed these symptoms were related to the intake of zonisamide, we immediately instructed the patient to discontinue the drug. At 3 days after discontinuing the drug, his myopia improved, and corrected visual acuities with the previous glasses increased to 1.0 in both eyes. @*Conclusions@#Zonisamide is a sulfonamide anticonvulsant that may cause acute myopic shift and a reduction in the anterior chamber depth. Therefore, physicians must consider the possibility of these complications occurring, when diagnosing a sudden blurring of vision in patients who are taking sulfonamide medications.

A Case of Steatocystoma Simplex and Sebaceous Gland Hyperplasia of the Bilateral Lacrimal Caruncle

PURPOSE: A case of bilateral lacrimal caruncle steatocystoma simplex and sebaceous gland hyperplasia, which rarely occurs in the periocular area, is reported. CASE SUMMARY: A 42-year-old female presented with a bilateral caruncular mass, which had been growing for a few months. A physical examination revealed soft, non-tender, rounded masses and no other ophthalmic findings. Under local anesthesia, the masses were completely excised. In the histopathological examination, a cystic mass containing a sebaceous gland in the stratified squamous epithelium cyst wall was found. A hyperplastic sebaceous gland and a dilated sebaceous gland duct were also found. Steatocystoma simplex and sebaceous gland hyperplasia, respectively, were diagnosed. There was no recurrence or complication after excision. CONCLUSIONS: Steatocystoma simplex and sebaceous gland hyperplasia are benign tumors that rarely occur in the lacrimal caruncle. They can be diagnosed and treated by complete excision. Steatocystoma simplex and sebaceous gland hyperplasia should therefore be considered as differential diagnoses of a lacrimal caruncle mass.

Comparison between Optic Disc Torsion of Fellow Eyes in Unilateral Normal-tension Glaucoma and Normal Eyes

PURPOSE: To determine the association between optic disc tilt and torsion of glaucomatous and fellow eyes of unilateral normal-tension glaucoma (NTG) patients and normal. METHODS: We measured optic disc tilt and torsion of 23 unilateral NTG patients and 23 normal controls by analyzing fundus photography and compared 3 groups. We also measured retinal nerve fiber layer (RNFL) thickness through optical coherence tomography in 23 unilateral NTG patients and compared the findings with those of normal eyes. RESULTS: The mean values of optic disc tilt ratio and torsion degree in glaucomatous eyes were 1.17 ± 0.19° and 15.57 ± 8.16°, respectively, while those in fellow eyes were 1.10 ± 0.10° and 8.26 ± 5.20°. There was no significant difference in tilt ratio (p = 0.109), but there was a significant difference in torsion degree (p = 0.001). The mean values of optic disc tilt ratio and optic disc torsion in the controls were 1.11 ± 0.07° and 3.25 ± 2.69°, respectively. Also, there was no significant difference in optic disc tilt ratio (p = 0.601), but a significant difference in optic disc torsion between fellow eyes and controls (p < 0.001). The RNFL thickness of the same torsion direction in unilateral NTG eyes was measured to be 49.35 ± 17.18 µm smaller than the normal value (mean RNFL thickness: 71.91 ± 16.92 µm). Reduced RNFL thickness of the same torsion direction between glaucomatous eyes and fellow eyes was significantly different (p < 0.001). In addition, it was confirmed that RNFL thickness was significantly decreased according to the degree of disc torsion (p = 0.024). CONCLUSIONS: The optic disc torsion showed a significant difference between glaucomatous and fellow eyes in unilateral NTG patients and normal controls. Also, the RNFL thickness significantly decreased according to the degree of the optic disc torsion. Therefore, fellow eyes of unilateral NTG patients need to be carefully monitored for the progression of glaucoma.

A Case of Conjunctival Lithiasis with Clinical Manifestations of Superior Limbic Keratoconjunctivitis

PURPOSE: To report a case of conjunctival lithiasis with clinical manifestations of superior limbic keratoconjunctivitis. CASE SUMMARY: A 40-year-old male complained of pain, foreign body sensation and injection in the left eye lasting 1 month. The slit-lamp examination revealed injection of the superior bulbar conjunctiva, linear corneal band opacity, fine punctate staining and epithelial defect in the superior cornea area. After eversion of the left upper eyelid, there were many various-sized conjunctional concretions and inflammation in the superior tarsal conjunctiva. Therefore, we considered conjunctival lithiasis-induced clinical manifestations of superior limbic keratoconjunctivitis and then removed the conjunctival concretions using a 30-gauge needle. After the procedures, artificial tears, antibiotic eye drops, steroid eye drops and a therapeutic contact lens were applied. After 1 week, all symptoms and signs improved and there was no recurrence for 4 months. CONCLUSIONS: Mechanical stimulation by severe conjunctival lithiasis can induce clinical manifestations of superior limbic keratoconjunctivitis. Therefore, in patients with clinical manifestations of superior limbic keratoconjunctivitis, conjunctival lithiasis should be considered by observing the superior tarsal conjunctiva more closely.

A Case of Posterior Reversible Encephalopathy Syndrome with Bilateral Visual Impairment

PURPOSE: To report a case of recovery of bilateral cortical blindness in a patient with posterior reversible encephalopathy syndrome. CASE SUMMARY: A 46-year-old female visited the ophthalmology department due to abrupt visual acuity decrease. Ten days earlier, she had received conservative management due to anemia caused by menorrhagia and uterine prolapse. She underwent a gynecological operation to remove a uterine myoma two days previously, and was given a blood transfusion postoperatively because of excessive bleeding. After the transfusion, she complained of acute blurred vision. Her best corrected visual acuity (BCVA) was hand motion 10 cm in both eyes. There were no abnormal specific findings except retinal dot hemorrhage at the temporal side in the left eye on fundus examination. Her pupillary light reflex was normal and optical coherence tomography examination was unremarkable in both eyes. However, flash visual evoked potential findings showed reduced P100 amplitude in both eyes and she was diagnosed with posterior reversible encephalopathy syndrome based on brain magnetic resonance imaging. After close observation without any treatment, the symptoms gradually improved. Finally, her BCVA recovered to 1.0 and P1 and P100 amplitudes were restored to normal range in both eyes at 16 weeks from the first diagnosis. CONCLUSIONS: A patient complained of bilateral visual loss without other neurological symptoms after chronic blood loss and blood transfusion. She recovered visual acuity completely with prompt diagnosis of posterior reversible encephalopathy syndrome and close observation only.

The Long-term Clinical Outcome after Corneal Collagen Cross-linking in Korean Patients with Progressive Keratoconus

PURPOSE: To evaluate the long-term clinical effectiveness and safety of corneal collagen cross-linking (CXL) in progressive keratoconus compared with untreated contralateral eyes. METHODS: In this retrospective study, nine eyes of nine patients with progressive keratoconus who received CXL (treatment group) and nine untreated contralateral eyes with keratoconus (control group) were included. All patients were followed for at least 5 years and assessed with best-corrected visual acuity, maximum keratometry, mean keratometry, corneal astigmatism, and corneal thickness. Clinical data were collected preoperatively and at 1, 3, 6, 12, 24, 36, 48, and 60 months, postoperatively. RESULTS: Mean best-corrected visual acuity improved significantly from 0.58 ± 0.37 logarithm of minimum angle of resolution preoperatively to 0.39 ± 0.29 logarithm of minimum angle of resolution at 5 years after corneal CXL (p = 0.012). There was significant flattening of the maximum keratometry and mean keratometry from preoperative values of 63.39 ± 10.89 and 50.87 ± 6.27 diopter (D) to postoperative values of 60.89 ± 11.29 and 49.54 ± 7.23 D, respectively (p = 0.038, 0.021). Corneal astigmatism decreased significantly from 7.20 ± 1.83 D preoperatively to 5.41 ± 1.79 D postoperatively (p = 0.021). The thinnest corneal thickness decreased from 434.00 ± 54.13 to 365.78 ± 71.58 µm during 1 month after treatment, then increased to 402.67 ± 52.55 µm at 5 years, which showed a statistically significant decrease compared to the baseline (p = 0.020). In the untreated contralateral eyes, mean keratometry increased significantly at 2 years compared with the baseline (p = 0.043). CONCLUSIONS: CXL seems to be an effective and safe treatment for halting the progression of keratoconus over a long-term follow-up period of up to 5 years in progressive keratoconus.

Clinical Usefulness of UBM in the Sitting Position in Anterior Chamber Depth and Angle Measurements

PURPOSE: We compared the measurements of anterior chamber depth (ACD) and anterior chamber angle (ACA) using ultrasound biomicroscopy (UBM) in the sitting position compared with IOL Master(R), Pentacam(R), and Spectralis optical coherence tomography (OCT) to evaluate the clinical usefulness of UBM in the sitting position. METHODS: We evaluated 92 eyes in 47 healthy adults. ACD was measured by IOL Master(R), Pentacam(R), and UBM. ACA was measured using Pentacam(R), UBM, and Spectralis OCT. UBM was performed in the sitting position using bag/balloon technology. Measured values were compared statistically. RESULTS: ACD measured by IOL Master(R), Pentacam(R), and UBM was 3.57 +/- 0.32 microm, 3.64 +/- 0.33 microm and 3.51 +/- 0.32 microm, respectively. UBM measurements of ACD were significantly shallower than with the other methods (p 0.8, p 0.05). There was strong correlation between UBM and Spectralis OCT (r = 0.957) but moderate correlation between Pentacam(R) and UBM and Pentacam(R) and Spectralis OCT (r = 0.557, 0.571, respectively, p < 0.05). Specifically, ACA of the superior quadrant showed a low correlation between Pentacam(R) and UBM and Pentacam(R) and Spectralis OCT (r = 0.257, 0.295, respectively). CONCLUSIONS: ACD measured by UBM in the sitting position was shallower compared to the other methods; however, ACD measured by IOL Master(R), Pentacam(R), and UBM showed significant correlations among the methods. The mean ACA measured by Pentacam(R), UBM, and Spectralis OCT showed no significant differences. Due to the high correlation of ACA measurements between UBM and Spectralis OCT in the present study, UBM is expected to be a good tool for measuring anterior segment parameters.

Three Cases of Pupil Abnormality in Herpes Zoster Ophthalmicus

PURPOSE: We report the occurrence of pupil abnormality in 3 patients with herpes zoster ophthalmicus. CASE SUMMARY: Three patients diagnosed with herpes zoster ophthalmicus developed pupil abnormality. (Case 1) A 37-year-old male diagnosed 1 month prior with anterior uveitis secondary to herpes zoster ophthalmicus presented with peripheral corneal erosions, inflammatory cells in the anterior chamber, diffuse iris atrophy, almost fully-dilated pupils, and loss of pupil light reflex in the right eye. (Case 2) A 72-year-old male presented with vesicles on the right side of the face, and dendritic corneal ulcer, and inflammatory cells in the anterior chamber on initial examinations. After 5 days without treatment by his choice, decreased vision, decreased pupil light reflex, and ovoid-shaped pupils developed. (Case 3) A 63-year-old female presented with left ocular pain, vesicles around the left eye, dendritic corneal ulcer, inflammatory cells in the anterior chamber, and isocoric pupils with normal pupil light reflexes. However, in her left eye, the pupillary ruff was partially lost and the pupil was larger than the right pupil after the start of a 3-week treatment regimen. The pupil in Case 2 returned to normal after 1 month, but in cases 1 and 3, no improvements of pupil abnormalities were observed during the follow-up period. CONCLUSIONS: Herein we presented 3 patients that were diagnosed with herpes zoster ophthalmicus and subsequently developed pupil abnormalities. In the cases of pupil abnormalities, checking for a history of herpes zoster ophthalmicus is necessary to make a differential diagnosis.

Corneal Crosslinking in Far-Advanced Keratoconus

PURPOSE: To report 2 cases of far-advanced keratoconus with a high value of maximum keratometry and very thin corneas treated with corneal crosslinking (CXL). CASE SUMMARY: The thinnest corneal thickness of an 18-year-old woman with maximum keratometry of 106.5 D (case 1) was 335 microm. The thinnest corneal thickness of a 43-year-old man with maximum keratometry of 120.3 D (case 2) was 345 microm. The two cases underwent a customized topography and pachymetry-guided epithelial debridement technique to preserve the epithelium where the cornea was within 2 mm around the cone and subsequent CXL. Postoperative maximum keratometry was 97.2 D 24 months after CXL in case 1 and 109.3 D 18 months after CXL in case 2. Postoperatively, the thinnest corneal thickness was 343 microm in case 1 and 162 microm in case 2. The corneal thickness in case 1 was stabilized during the follow-up examination. The pupil center and apex of the corneal thickness in case 2 with the higher maximum keratometry was stabilized, but the thinnest corneal thickness was decreased immediately after CXL and did not recover before CXL. CONCLUSIONS: CXL was performed in 2 cases of far-advanced keratoconus. Results showed reduced maximum keratometry but, variable values in corneal thickness during the follow-up examination in the 2 cases. Longer follow-up is necessary, and CXL should be performed cautiously, especially for patients with far-advanced keratoconus.