Kook Lee

Optic Disc Torsion Direction Predicts the Location of Glaucomatous Damage in Normal-Tension Glaucoma Patients with Myopia

OBJECTIVE To characterize optic disc tilt and torsion in normal-tension glaucoma (NTG) patients with myopia and to evaluate the relationship between optic disc tilt and torsion with the location of visual field (VF) defect. DESIGN Retrospective, case-control design. PARTICIPANTS Two hundred twenty-five NTG patients. METHODS Patients were divided into a myopic NTG group (spherical equivalent more than -2.00 diopters [D] or axial length more than 24.0 mm; n = 166) and nonmyopic NTG group (spherical equivalent less than -0.50 D or axial length less than 24.0 mm; n = 59). Disc tilt, which was identified by the tilt ratio, disc torsion, and area of peripapillary atrophy (PPA), was measured from disc photographs. Patients were divided further into superior and inferior defect groups according to the location of the VF defect in the pattern deviation map. Logistic regression analysis was used to determine the relationship between ocular factors, including tilt ratio, torsion degree, and the VF defect location. MAIN OUTCOME MEASURES Tilt ratio, torsion degree, PPA area, and location of VF defect. RESULTS Among 225 NTG eyes, 166 (73.8%) were myopic eyes. The myopic NTG group was significantly younger (42.85 years) than the nonmyopic NTG group (60.73 years). Disc tilt (45.8%) and torsion (75.9%) were significantly more prevalent in the myopic NTG group than in the nonmyopic NTG group. Although just short of statistical significance (P = 0.057), PPA area was larger in the myopic NTG group. The VF defect location was significantly different between the 2 groups, with superior defects more prevalent in the myopic NTG group (69.9%; P<0.001). Torsion degree was significantly different in the superior defect group (18.45°) compared with the inferior defect group (-3.81°; P = 0.001). Torsion degree was the only factor related to VF defect location in both univariate (P = 0.001) and multivariate (P = 0.014) logistic regression analyses. CONCLUSIONS Korean NTG patients had a high prevalence of myopia and young age. Optic disc tilt and torsion were highly prevalent in Korean NTG patients with myopia. The direction of the optic disc torsion may predict the location of damage.

Torsion of the optic nerve head is a prominent feature of normal-tension glaucoma.

PURPOSE To compare optic nerve head (ONH) morphology between eyes with normal-tension glaucoma (NTG) and primary open-angle glaucoma (POAG). METHODS Seventy-eight NTG patients and 78 POAG patients matched according to age and axial length were analyzed. Optic nerve head tilt and torsion were identified from cross-sectional images of optical coherence tomography. The degree of horizontal, vertical, and maximum ONH tilt and torsion was compared between NTG and POAG eyes, and additional comparisons were based on the presence of myopia and the location of the visual field defect. Logistic regression analysis was used to determine the factors related to the degree of ONH torsion. RESULTS Vertical (P = 0.610) and horizontal tilt degree (P = 0.746) did not differ between NTG and POAG eyes. However, torsion degree (P = 0.022) differed significantly between NTG and POAG eyes. Direction of vertical tilt (P = 0.040) and torsion (P < 0.001) showed more prevalent superior tilt and torsion in NTG eyes (21.8% and 33.3%, respectively) compared to POAG eyes (10.3% and 10.3%, respectively). Myopic NTG eyes showed greater torsion degree (P = 0.014) than nonmyopic NTG eyes, which was not observed in the comparison between myopic and nonmyopic POAG eyes. Only NTG eyes showed a significant difference in the degree of maximum tilt (P < 0.001) and torsion (P < 0.001) and the direction of vertical tilt (P < 0.001) and torsion (P = 0.010) by the location of visual field defect. Longer axial length, maximum tilt degree, and diagnosis of NTG were the factors related to the degree of ONH torsion. CONCLUSIONS Normal-tension glaucoma eyes had a greater ONH torsion compared to POAG eyes with matched axial length. The direction of the ONH tilt and torsion was related to the location of the visual field defect only in NTG eyes.

Lacrimal gland duct stones: misdiagnosed as chalazion in 3 cases

OBJECTIVE To report 3 cases of lacrimal gland duct stones misdiagnosed as chalazion. DESIGN Retrospective case series. PARTICIPANTS Three patients with lacrimal gland duct stones misdiagnosed as chalazion at a local clinic between 2010 and 2012. METHODS A thorough review of clinical, imaging, and histopathologic manifestations. RESULTS Clinical manifestations of lacrimal gland duct stones included conjunctival injection, lid swelling, tenderness, and ocular discharge, which are similar to chalazion symptoms. Computed tomography revealed a relatively well-defined, high-density mass near the lacrimal gland. Histopathologic examination of excised material revealed calcified amorphous stones. CONCLUSIONS Intractable chalazion-like lesions at the lateral canthal area near the lacrimal gland should be carefully examined; imaging studies are required to confirm the presence of lacrimal gland duct stones, which require surgical removal.

Acute Retrobulbar Optic Neuropathy as the Sole Manifestation of Subarachnoid Haemorrhage from a Ruptured Anterior Communicating Artery Aneurysm

Abstract Anterior communicating artery aneurysm is the most common form of intracranial aneurysm and subarachnoid haemorrhage (SAH) is the common presenting feature of anterior communicating artery aneurysms. In general, patients with SAH from anterior communicating artery aneurysm present with neurological deficit. We report an interesting case of a 60-year-old man who presented with acute monocular vision loss accompanied by periorbital pain without any neurological deficit, finally diagnosed with SAH from ruptured anterior communicating artery aneurysm. Five months after immediate craniotomy with aneurysm neck clipping, his visual acuity was improved to 20/63 with a pale optic disc appearance. Acute retrobulbar optic neuropathy may be the sole manifestation of SAH from ruptured anterior communicating artery aneurysm. Unilateral decrease of visual acuity with periorbital pain, in the absence of other neurological change, may be the initial and isolated sign.