Effect of decentration and tilt on the in vitro optical quality of monofocal and trifocal intraocular lenses.

PURPOSE: To evaluate and compare the effect of decentration and tilt on the optical quality of monofocal and trifocal intraocular lenses (IOL). METHODS: Optical quality of a monofocal IOL (AcrySof IQ SN60WF; Alcon Laboratories, Inc., USA) and a trifocal IOL (AcrySof IQ PanOptix; Alcon Laboratories, Inc., USA) was assessed using an in vitro optical bench (OptiSpheric IOL R&D; Trioptics GmbH, Germany). At apertures of 3.0 mm and 4.5 mm, modulation transfer function (MTF) at spatial frequency of 50 lp/mm, MTF curve and the United States Air Force (USAF) resolution test chart of the two IOLs were measured and compared at their focus with different degrees of decentration and tilt. Optical quality at infinity, 60 cm and 40 cm and the through-focus MTF curves were compared when the two IOLs were centered at apertures of 3.0 mm and 4.5 mm. Spectral transmittance of the two IOLs was measured by the UV-visible spectrophotometer (UV 3300 PC; MAPADA, China). RESULTS: The SN60WF and the PanOptix filtered blue light from 400 to 500 nm. Both IOLs at the far focus and the PanOptix at the intermediate focus showed a decrease in optical quality with increasing decentration and tilt. The PanOptix demonstrated enhanced optical quality compared to the previous gradient at the near focus at a decentration range of 0.3-0.7 mm with a 3.0 mm aperture, and 0.5 mm with a 4.5 mm aperture, whereas other conditions exhibited diminished optical quality with increasing decentration and tilt at the focus of both IOLs. When the two IOLs were centered, the SN60WF had better optical quality at infinity, while the PanOptix had better optical quality at 60 cm and 40 cm defocus. The optical quality of the SN60WF exceeded that of the PanOptix at far focus, with a 3 mm aperture decentration up to 0.7 mm and a 4.5 mm aperture decentration up to 0.3 mm; this observation held true for all tilts, irrespective of aperture size. As both decentration and tilt increased, the optical quality of the SN60WF deteriorated more rapidly than that of the PanOptix at the far focal point. CONCLUSIONS: The SN60WF showed a decrease in optical quality with increasing decentration and tilt. Optical quality of the PanOptix at the near focus increased in some decentration conditions and decreased in some conditions, while it showed a decrease at the other focuses with increasing decentration. While tilt only had a negative effect on optical quality. When both IOLs were centered, the PanOptix provided a wider range of vision, while the SN60WF provided better far distance vision. At the far focus, the SN60WF has better resistance to tilt than the PanOptix, but the optical quality degrades more quickly when decentered and tilted.

Pulmonary cryptococcosis: comparison of CT findings in immunocompetent and immunocompromised patients.

BACKGROUND: Computed tomography (CT) findings in patients with pulmonary cryptococcosis have been reported, however, many reports were limited by the small number of patients, and not taken into account the distinction between immunocompetent and immunocompromised patients. PURPOSE: To retrospectively evaluate thoracic CT findings in patients with pulmonary cryptococcosis whose immune status ranged from normal to severely compromised, and determine characteristic imaging features of pulmonary cryptococcosis between patients with different immune status. MATERIAL AND METHODS: CT scan findings of 29 immunocompetent and 43 immunocompromised patients with clinically proven pulmonary cryptococcosis were reviewed retrospectively. Different patterns of CT scan abnormalities between immunocompromised and immunocompetent patients, AIDS and non-AIDS immunocompromised patients were compared by Fisher's exact test. RESULTS: Pulmonary nodules/masses, either solitary or multiple, were the most common CT finding, present in 65 (90.3%) of the 72 patients; associated findings included CT halo sign (n = 24), cavitation (n = 23), and air bronchogram (n = 17). Areas of consolidation (n = 14), areas of GGO (n = 13), linear opacities (n = 11), lymphadenopathy (n = 5), and pleural effusion (n = 8) were uncommon. The parenchymal abnormalities were peripherally located in 47 (65.2%) of the cases. Cavitations within nodules/masses were more frequently present in immunocompromised patients than in immunocompetent patients (P = 0.009), and in AIDS patients than in non-AIDS immunocompromised patients (P = 0.002). Air bronchograms within nodules/masses were more frequent present in immunocompetent patients than in immunocompromised patients (P = 0.005). Nodules/masses with halo sign were less frequent in AIDS patients than those in non-AIDS immunocompromised patients (P = 0.027). CONCLUSION: Pulmonary cryptococcosis should be considered in the differential diagnosis of solitary or multiple pulmonary nodules. Cavitations within nodules/masses were more commonly seen in immunocompromised patients, especially AIDS patients, while air bronchograms were more commonly seen in immunocompetent patients.

A giant cardiac lipoma associated with ventricular inversion and ventricular aneurysm: ultrasonography and CT imaging findings.

Cardiac lipomas are rare, mostly asymptomatic, and usually found incidentally during noncardiac examinations; however, they also can be symptomatic, depending on their size and location. Here, we report a case of surgically proved pericardial lipoma that was big and for which cardiac structures were substantially altered. The combination of CT imaging and ultrasonography enabled a precise diagnosis in terms of localization, tissue characterization, and complications of the tumor. The origin of the tumor, however, remains undetermined despite a series of postoperative CT scan and ultrasound examinations.

An animal experiment about early pulmonary candidiasis in immunosuppressive rabbits: thin-section CT images dynamically observed and proved by histopathological results.

BACKGROUND: Early detection and treatment of pulmonary fungal infection in immunocompromised patients has a profound impact on mortality. However, information available about the thin-section computed tomography (CT) findings of Candida pneumonia has largely been limited to isolated cases seen in reviews of various infections and to other acute lung diseases seen in immunocompromised patients. PURPOSE: To dynamically observe and evaluate CT findings in immunosuppressed animals with histopathologically confirmed pulmonary candidiasis at the acute stage. MATERIAL AND METHODS: Twenty-four New Zealand rabbits were randomly divided into an experimental group (n = 21) and a control group (n = 3). Pulmonary candidiasis was established by C. albicans inoculation via a transtracheal route in immunosuppressed rabbits in the experimental group, and an equivalent amount of normal saline was injected via the same way in the control group. Chest CT scan was performed before and on alternative days after inoculation/injection. Microbiological and pathological results were obtained by autopsy. RESULTS: In the experiment group, pulmonary candidiasis was successfully established in 13 rabbits as confirmed by microbiology and pathology. Areas of air-space consolidation were present in 10 (10/13) rabbits, with lobular distribution in six and lobar or segmental distribution in four, pathologically presenting as bronchopneumonia or hemorrhagic lung infarcts. Areas of ground-glass opacity (GGO) were identified in five (5/13) rabbits, three of which were associated with other abnormalities, presenting as bronchopneumonia or interstitial pneumonitis. Multiple nodules were seen in three (3/13) rabbits. They were clustered around bronchovascular bundles in two rabbits, and subpleural in the remaining one, pathologically presenting as hemorrhagic granulomas. Other less common CT findings included thickening of bronchovascular bundles (n = 3), linear opacity (n = 1), and pneumothorax (n = 1). No abnormality was detected by CT scan and pathological examination in the three rabbits of the control group. CONCLUSION: Peripheral multiple areas of lobular consolidation and/or GGO representing bronchopneumonia were the most common thin-section CT findings of pulmonary candidiasis at the early stage.