Assessment of Artifacts and Reproducibility across Spectral- and Time-Domain Optical Coherence Tomography Devices

Purpose To report the frequency of optical coherence tomography (OCT) scan artifacts and to compare macular thickness measurements, interscan reproducibility, and interdevice agreeability across 3 spectral-domain (SD) OCT (also known as Fourier domain; Cirrus HD-OCT, RTVue-100, and Topcon 3D-OCT 1000) devices and 1 time-domain (TD) OCT (Stratus OCT) device. Design Prospective, noncomparative, noninterventional case series. Participants Fifty-two patients seen at the New England Eye Center, Tufts Medical Center Retina Service, between February and August 2008. Methods Two scans were performed for each of the SD OCT protocols: Cirrus macular cube 512×128 (software version 3.0; Carl Zeiss Meditec, Inc., Dublin, CA), RTVue (E)MM5 and MM6 (software version 3.5; Optovue, Inc., Fremont, CA), Topcon 3D Macular and Radial (software version 2.12; Topcon, Inc., Paramus, NJ), in addition to 1 TD OCT scan via Stratus macular thickness protocol (software version 4.0; Carl Zeiss Meditec, Inc.). Scans were inspected for 6 types of OCT scan artifacts and were analyzed. Interscan reproducibility and interdevice agreeability were assessed by intraclass correlation coefficients (ICCs) and Bland-Altman plots, respectively. Main Outcome Measures Optical coherence tomography image artifacts, macular thickness, reproducibility, and agreeability. Results Time-domain OCT scans contained a significantly higher percentage of clinically significant improper central foveal thickness (IFT) after manual correction (11-μm change or more) compared with SD OCT scans. Cirrus HD-OCT had a significantly lower percentage of clinically significant IFT (11.1%) compared with the other SD OCT devices (Topcon 3D, 20.4%; Topcon Radial, 29.6%; RTVue (E)MM5, 42.6%; RTVue MM6, 24.1%; P = 0.001). All 3 SD OCT devices had central foveal subfield thicknesses that were significantly more than that of TD OCT after manual correction (P<0.0001). All 3 SD OCT devices demonstrated a high degree of reproducibility in the central foveal region (ICCs, 0.92–0.97). Bland-Altman plots showed low agreeability between TD and SD OCT scans. Conclusions Out of all OCT devices analyzed, cirrus HD-OCT scans exhibited the lowest occurrence of any artifacts (68.5%), IFT (40.7%), and clinically significant IFT (11.1%), whereas Stratus OCT scans exhibited the highest occurrence of clinically significant IFT. Further work on improving segmentation algorithm to decrease artifacts is warranted.Research to Prevent Blindness, Inc. (United States) (Challenge Grant)National Institutes of Health (U.S.) (Grant R01-EY11289-23)National Institutes of Health (U.S.) (Grant R01-EY13178-07)National Institutes of Health (U.S.) (Grant P30-EY008098)United States. Air Force Office of Scientific Research (Grant FA9550-07-1-0101)United States. Air Force Office of Scientific Research (Grant FA9550-07-1-0014

Acute vision loss in intracranial hypertension secondary to choroidal neovascularization

We observed a rare ocular complication of choroidal neovascularisation (CNV) in a patient with idiopathic intracranial hypertension (IIH). The mechanism and treatment of such cases remain controversial

Nonmydriatic ocular fundus photography among patients with focal neurologic deficits in an emergency department (ED)

While several large cohort studies have associated ocular fundus abnormalities with the long-term risk of stroke, the value of ocular fundus examination in patients presenting with focal neurologic deficits, particularly suspected transient ischemic attack (TIA) and stroke, has not been evaluated. The ABCD2 score is widely used for the risk stratification of patients with suspected TIA, but does not include fundus findings. Our objective was to determine the frequency of and the predictive factors for abnormal ocular fundus findings among ED patients who presented with focal neurologic deficits

Asymmetric Papilledema with Surprising Outcomes

The diagnosis of pseudotumor cerebri (PTC) can be straight forward when there is bilateral optic disc edema and when the symptoms, signs, and work-up match the modified Dandy-Walker criteria. However, in atypical patient presentations with asymmetric disc edema, there are diagnostic and treatment decision dilemmas

Characterization of Charcot-Marie-Tooth optic neuropathy

Varying degrees of optic neuropathy can be seen in patients with Charcot-Marie-Tooth (CMT) disease. To define and characterize the extent of optic neuropathy in patients with CMT2A and CMT1A, two patients from both sub-classifications were evaluated. All patients underwent complete neuro-ophthalmic examinations, and optical coherence (OCT) measurements of the retinal nerve fiber layer (RNFL) and ganglion cell layer complex (GCC) were obtained, along with pattern visual evoked potential (VEP) and pattern electroretinogram (ERG) recordings. RNFL thickness measurements were decreased in both patients with CMT2A, and normal in both patients with CMT1A. GCC measurements were decreased in both patients with CMT2A, mildly decreased in one patient with CMT1A and normal in the second CMT1A patient. VEP latencies were delayed in one patient with CMT2A and one patient with CMT1A. VEP latencies were immeasurable in the other CMT2A patient and not obtained in the second CMT1A patient. Pattern ERG P50-N95 amplitudes were decreased in both patients with CMT2A and normal in one patient with CMT1A. The pattern ERG was immeasurable in the second patient with CMT1A. The pattern of RNFL and GCC thinning in CMT2A with optic neuropathy, a subset of HMSN VI, closely resembles that seen in other mitochondrial optic neuropathies

An Atypical Presentation of Giant Cell Arteritis

We observed an atypical presentation of giant cell arteritis that initially made the diagnosis difficult

Nitric oxide-induced homologous recombination in Escherichia coli is promoted by DNA glycosylases

Nitric oxide (NO*) is involved in neurotransmission, inflammation, and many other biological processes. Exposure of cells to NO* leads to DNA damage, including formation of deaminated and oxidized bases. Apurinic/apyrimidinic (AP) endonuclease-deficient cells are sensitive to NO* toxicity, which indicates that base excision repair (BER) intermediates are being generated. Here, we show that AP endonuclease-deficient cells can be protected from NO* toxicity by inactivation of the uracil (Ung) or formamidopyrimidine (Fpg) DNA glycosylases but not by inactivation of a 3-methyladenine (AlkA) DNA glycosylase. These results suggest that Ung and Fpg remove nontoxic NO*-induced base damage to create BER intermediates that are toxic if they are not processed by AP endonucleases. Our next goal was to learn how Ung and Fpg affect susceptibility to homologous recombination. The RecBCD complex is critical for repair of double-strand breaks via homologous recombination. When both Ung and Fpg were inactivated in recBCD cells, survival was significantly enhanced. We infer that both Ung and Fpg create substrates for recombinational repair, which is consistent with the observation that disrupting ung and fpg suppressed NO*-induced recombination. Taken together, a picture emerges in which the action of DNA glycosylases on NO*-induced base damage results in the accumulation of BER intermediates, which in turn can induce homologous recombination. These studies shed light on the underlying mechanism of NO*-induced homologous recombination

Large Right Hypophyseal Aneurysm Causing a Junctional Scotoma

Right, multi-lobulated superior hypophyseal artery aneurysm measuring 1.6 x 1.2 x 2.2 cm with 6 mm neck causing a right junctional scotoma . Images from a brain CT with contrast, a brain CT angiography with contrast, cerebral angiogram, Humphrey visual fields and ocular fundus photographs are included.VBneurodisaneurysms, EECneurodisaneurysms, VPavpopticchiasm, EECavpopticchiasm, VBchiasmalvisualfielddefects, EECchiasmalvisualfielddefect