Individual vs simultaneous macular and optic disc measurements with spectral domain optical coherence tomography in glaucoma and healthy eyes.

We assessed the repeatability and agreement of ganglion cell complex (GCC) in the macular area and the peripapillary retinal nerve fiber layer (ppRNFL) with individual and combined macula and disc scans. The macular GCC and ppRNFL thicknesses from 34 control eyes and 43 eyes with glaucoma were measured with the Canon Optical Coherence Tomography (OCT) HS-100. Two repeated measurements were performed with both scan modes. The repeatability limit (Rlim) and agreement analysis were performed. The individual scan showed better repeatability than the combined scan in both groups. However, the differences in the Rlim for the GCC in most sectors were lower than 3 µm (axial resolution of the OCT), and this was larger than 3 µm for most of the ppRNFL sectors. The mean differences in the thickness between both scan modes for the GCC and ppRNFL measurements were less than 3 and 6 µm, respectively. The interval of the limits of agreement was about 10 µm in some sectors for the GCC, and about 40 and 60 µm in some sectors in controls and glaucoma eyes, respectively. Both scan modes showed good repeatability in both groups. The agreement results suggest that the scan modes cannot be used interchangeably.

Visual flow scene effects on the somatogravic illusion in non-pilots.

INTRODUCTION: The somatogravic illusion (SGI) is easily broken when the pilot looks out the aircraft window during daylight flight, but it has proven difficult to break or even reduce the SGI in non-pilots in simulators using synthetic visual scenes. Could visual-flow scenes that accommodate compensatory head movement reduce the SGI in naive subjects? METHODS: We investigated the effects of visual cues on the SGI induced by a human centrifuge. The subject was equipped with a head-tracked, head-mounted display (HMD) and was seated in a fixed gondola facing the center of rotation. The angular velocity of the centrifuge increased from near zero until a 0.57-G centripetal acceleration was attained, resulting in a tilt of the gravitoinertial force vector, corresponding to a pitch-up of 30 degrees. The subject indicated perceived horizontal continuously by means of a manual adjustable-plate system. We performed two experiments with within-subjects designs. In Experiment 1, the subjects (N = 13) viewed a darkened HMD and a presentation of simple visual flow beneath a horizon. In Experiment 2, the subjects (N = 12) viewed a darkened HMD, a scene including symbology superimposed on simple visual flow and horizon, and this scene without visual flow (static). RESULTS: In Experiment 1, visual flow reduced the SGI from 12.4 +/- 1.4 degrees (mean +/- SE) to 8.7 +/- 1.5 degrees. In Experiment 2, the SGI was smaller in the visual flow condition (9.3 +/- 1.8 degrees) than with the static scene (13.3 +/- 1.7 degrees) and without HMD presentation (14.5 +/- 2.3 degrees), respectively. CONCLUSION: It is possible to reduce the SGI in non-pilots by means of a synthetic horizon and simple visual flow conveyed by a head-tracked HMD. This may reflect the power of a more intuitive display for reducing the SGI.

Cyclooxygenase-2 expression in squamous cell carcinoma of the oral cavity and pharynx: association to p53 and clinical outcome.

Cyclooxygenase-2 (COX-2) expression is up-regulated in transformed cells and in malignant tissues, including tumours of the head and neck, and it has prognostic significance in many types of cancer. COX-2 expression is suppressed by the wild-type but not by the mutant tumour suppressor gene TP53. The purpose of this study was to investigate the association between the expression of COX-2 and the clinical outcome in patients with oral and pharyngeal squamous cell carcinoma (SCC), and to examine its relationship to p53. Immunohistochemistry showed an elevated COX-2 expression in 88% (n = 57; strong 38, weak 19) of the 65 tumour samples. The staining intensity was not associated with patient or tumour characteristics, nor with the immuhistochemical expression of p53. Kaplan-Meier analysis showed no significant correlation between COX-2 expression and recurrence-free or overall survival, but a strong p53 expression was associated with a poor recurrence-free (p = 0.001, log-rank) and overall survival (p = 0.003). We conclude that, unlike strong p53 expression, COX-2 expression does not have prognostic significance in advanced oral and pharyngeal SCCs.

Tenascin-C expression and its prognostic significance in oral and pharyngeal squamous cell carcinoma.

BACKGROUND: Tenascin-C (Tn-C) is an extracellular matrix protein with growth-, invasion- and angiogenesis-promoting activities. It is up-regulated in tumorigenesis and has been suggested to correlate with prognosis in various carcinomas, but its significance in squamous cell carcinoma of the head and neck remains unknown. The purpose of this study was to examine the prognostic significance of Tn-C expression in oral and pharyngeal squamous cell carcinomas. PATIENTS AND METHODS: Tn-C expression was determined by immunohistochemistry in 65 consecutive tumors from patients with primary oral and pharyngeal squamous cell carcinoma. Based on staining intensity, both the stroma and invasion border were separately classified into two groups and the results correlated with overall survival (OS) and disease-free survival (DFS). RESULTS: The tumor stroma showed strong Tn-C expression in 56 (86%) samples, and weak Tn-C expression in 9 (14%). At the invasion border, Tn-C expression was strong in 38 (58%) samples and weak in 27 (42%). Tn-C expression was not a statistically significant predictor of survival and there was no correlation between Tn-C expression and tumor or patient characteristics. CONCLUSION: Tn-C protein was overexpressed in the majority of our oral and pharyngeal squamous cell carcinoma samples. The presence of TnC did not appear to predict for OS or DFS.