Biomedical subjects

K Kertész

Publications and source records attributed to K Kertész.

4 recordsLinked to original sources

PubMed2006

Corneal endothelial function after phacoemulsification using the fluid-based system compared to conventional ultrasound technique.

AIM: To quantitatively assess corneal endothelial changes after phacoemulsification with the fluid-based system compared to conventional ultrasound technique. METHODS: This prospective, randomized clinical study included patients with cataract who were randomly assigned either to have phacoemulsification with the fluid-based system (30 eyes of 30 patients--Group 1) or with traditional ultrasound (30 eyes of 30 patients--Group 2). Patients who were available at each follow-up visit (25 eyes in both groups) were enrolled in the statistical analysis. Endothelial function was evaluated by measuring central corneal thickness, central endothelial cell density (ECD), mean cell size, and coefficient of variation in cell size preoperatively, 10 days, 1 and 3 months, and 1 year after surgery. Statistical analyses were performed using two-way repeated measure ANOVA. RESULTS: An acute, reversible increase of central corneal thickness (CCT) was found 10 days after surgery, which was similar in both groups (P=0.35). ECD decreased, whereas mean cell size increased significantly immediately after surgery. However, the impairments were finished after 1 month. The alterations were similar in both groups (ECD: P=0.99; mean cell size: P=0.85). The coefficient of variation in cell size remained stable after surgery (P=0.08), and significant difference was not found between groups (P=0.99). The endothelial cell loss (ECL) was 6.5+/-8.4% in Group 1 and 6.5+/-11.7% in Group 2 (P=0.69). CONCLUSIONS: Corneal endothelial changes were similar using the fluid-based system compared to the traditional ultrasound technique. The fluid-based method proved to be as safe as conventional ultrasound in cataract surgery.

Aged↗

PubMed2006

[Initial experience with transpalpebral orbital lipectomy].

PURPOSE: The aim of this study was to evaluate the short-term effectiveness of transpalpebral orbital lipectomy. METHOD: Using a transpalpebral approach, 2.0-6.5 ml connective tissue was removed from 50 orbits of 33 patients with mild to severe Graves' orbitopathy (25 females, 8 males) over a 5-year period. Indications for surgery comprised cosmetic correction of exophthalmos (27/33 patients), corneal damage (5/33), and rapid bilateral deterioration of visual acuity in 1 patient. RESULTS: In 27 patients undergoing correction for aesthetic purposes no change in visual acuity ensued; in 4 of 5 keratopathy patients an improvement in visual acuity was detected. Diplopia ceased in 4 of 13 patients, diminished in 3 of 13 cases, and constantly increased in 2 of 13 cases. The high intraocular pressure returned to normal in 8 of 13 patients. The proptosis was reduced at 3.2+/-1.3 mm. CONCLUSION: Transpalpebral orbital lipectomy is a low-risk, highly effective technique for orbital decompression in both acute and chronic cases of Graves' orbitopathy.

Adolescent↗

PubMed2006

Wing scale microstructures and nanostructures in butterflies--natural photonic crystals.

The aim of our study was to investigate the correlation between structural colour and scale morphology in butterflies. Detailed correlations between blue colour and structure were investigated in three lycaenid subfamilies, which represent a monophylum in the butterfly family Lycaenidae (Lepidoptera): the Coppers (Lycaeninae), the Hairstreaks (Theclinae) and the Blues (Polyommatinae). Complex investigations such as spectral measurements and characterization by means of light microscopy, scanning electron microscopy and transmission electron microscopy enabled us to demonstrate that: (i) a wide array of nanostructures generate blue colours; (ii) monophyletic groups use qualitatively similar structures; and (iii) the hue of the blue colour is characteristic for the microstructure and nanostructure of the body of the scales.

Animals↗

PubMed2003

Role of photonic-crystal-type structures in the thermal regulation of a Lycaenid butterfly sister species pair.

One of the possible functions of the photonic-crystal structure found on the wing scales of some butterflies is investigated. The optical and electron microscopic investigation of two male butterflies-blue (colored) and brown (discolored)-representing a sister species pair and originating from different altitudes, revealed that the blue color can be attributed unambiguously to the fine, spongelike medium, called "pepper-pot structure," present between the ridges and the cross ribs in the scales of the colored butterfly. Only traces of this structure can be found on the scales of the discolored butterfly. Other physical measurements, mainly optical reflectivity, transmission, and thermal measurements, are correlated with structural data and simulation results. The thermal measurements reveal that under identical illumination conditions the high-altitude butterfly reaches a temperature 1.3-1.5 times the temperature reached by the low-altitude butterfly. This is attributed to the photonic-crystal-like behavior of the pepper-pot structure, which significantly reduces the penetration of light with wavelength in the blue region of the spectrum into the body of the scales. This sheds some light on the adaptation that enhances the survival chance of the butterfly in a cold environment rich in blue and UV radiation.

Journal Article↗