Macular pigment and macular volume in eyes of patients with cystic fibrosis.

BACKGROUND: Because patients with cystic fibrosis (CF) are living longer, chronic malabsorption of carotenoids associated with CF resulting in decreased macular pigment (MP) may affect macular long-term health in later-life pathology. This study compared the macular pigment optical density (MPOD) and corresponding central macular volume (MV) of adult CF subjects and age-matched normal controls subjects to determine whether chronic malabsorption associated with CF could adversely affect macular photoreceptor anatomy. OBJECTIVE: Our aim was to compare MPOD with measurements of central MV in CF patients with age-matched controls. Design. In nine adult CF patients (ages: 29-46) without a history of carotenoid supplementation or known retinal or optic nerve disease MPOD and MV were measured by heterochromatic flicker photometry (HFP) and optical coherence tomography (OCT), respectively, and compared to results obtained from 14 age-matched controls. RESULTS: MPOD was significantly reduced at 15' and 30' eccentricities in CF subjects compared to normal subjects (mean difference -0.21 at 15', -0.25 at 30', p < 0.005). No significant difference, in MV noted at any of the eccentricities tested between CF and normal subjects (CF: normal MV ratios ranged from 0.94 to 1.1 for all eccentricities with p > 0.1 at all eccentricities). Best corrected vision acuity and fundus examination were normal in all subjects. CONCLUSIONS: Unsupplemented CF patients have markedly lower levels of macular carotenoids (e.g., lutein and zeaxanthin), but well-maintained visual function and no significant reductions in central MV primarily composed of macular photoreceptors. Future studies are needed to determine whether the lifelong decrease in protective central retinal carotenoids predisposes CF patients to later-life retinal pathology.

Wavefront sensorless modal deformable mirror correction in adaptive optics: optical coherence tomography.

We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and application of the resulting shapes to a deformable mirror, while optimizing using image sharpness as a merit function. We demonstrate that this technique can compensate for aberrations induced by trial lenses. Measurements of the point spread function before and after compensation demonstrate near diffraction limit imaging.

Fourier-domain optical coherence tomography of eyes with idiopathic epiretinal membrane: correlation between macular morphology and visual function.

PURPOSE: The purpose of this study is to evaluate the macular morphological changes associated with idiopathic epiretinal membrane (iERM) using high-resolution Fourier-domain optical coherence tomography (FD-OCT), as they correlate with visual acuity and microperimetry (MP-1). METHODS: In all, 24 eyes (19 subjects) with iERM were imaged prospectively using FD-OCT with axial resolution of 4.5 µm and transverse resolution of 10 to 15 µm. MP-1 and Stratus OCT were carried out in a subset of eyes. RESULTS: The mean log of the minimum angle of resolution best-corrected visual acuity (BCVA) was 0.18±0.16 (range: -0.08 to 0.48, Snellen equivalent 20/15(-1) to 20/60). ERM was visualized in all 24 eyes with FD-OCT and in 17 eyes (85%) of 20 eyes imaged with Stratus OCT. Although BCVA correlated with macular thickening in the central 1 mm sub-field of the Stratus ETDRS (P=0.0005) and macular volume (central 3 mm area) on FD-OCT (P<0.0001), macular thickening on thickness map and volume correlated poorly with decrease in macular sensitivity on MP-1 (P=0.16). On FD-OCT, foveal morphological changes correlated best with decrease in BCVA, the strongest being central foveal thickness (P<0.0001). Other significant changes included blurring of the foveal inner segment-outer segment (IS-OS) junction and/or Verhoeff's membrane, vitreal displacement of foveal outer nuclear layer and foveal detachment (P<0.05). Foveal IS-OS junction disruption was seen in 25% of eyes on Stratus OCT but in none of the eyes on FD-OCT. CONCLUSION: FD-OCT allowed improved visualization of ERM and associated foveal morphological changes that correlated best with BCVA. Macular thickening correlated weakly with decreased macular function as assessed by MP-1.

Outer retinal abnormalities associated with inner retinal pathology in nonglaucomatous and glaucomatous optic neuropathies.

Inner and outer retinal morphology were quantified in vivo for 6 nonglaucomatous and 10 glaucomatous optic neuropathy patients. Custom, ultrahigh-resolution imaging modalities were used to evaluate segmented retinal layer thickness in 3D volumes (Fourier-domain optical coherence tomography), cone photoreceptor density (adaptive optics fundus camera), and the length of inner and outer segments of cone photoreceptors (adaptive optics-optical coherence tomography). Quantitative comparisons were made with age-matched controls, or by comparing affected and nonaffected retinal areas defined by changes in visual fields. The integrity of outer retinal layers on optical coherence tomography B-scans and density of cone photoreceptors were correlated with visual field sensitivity at corresponding retinal locations following reductions in inner retinal thickness. The photoreceptor outer segments were shorter and exhibited greater variability in retinal areas associated with visual field losses compared with normal or less affected areas of the same patient's visual field. These results demonstrate that nonglaucomatous and glaucomatous optic neuropathies are associated with outer retinal changes following long-term inner retinal pathology.

Retinal microstructure in patients with EFEMP1 retinal dystrophy evaluated by Fourier domain OCT.

OBJECTIVES: To investigate retinal microstructure of patients affected with malattia leventinese (MLVT) and mutation in the EFEMP1 gene using high-resolution optical coherence tomography (OCT). METHODS: Patients diagnosed with MLVT received a comprehensive eye exam, full-field and multifocal electroretinogram testing and imaging with a high-resolution Fourier domain OCT (Fd-OCT, UC Davis Medical Center, Davis, USA; axial resolution: 4.5 microm, acquisition speed: 9 frames s(-1), 1000 A scans s(-1)) combined with a flexible scanning head (Bioptigen Inc. Durham, NC, USA). RESULTS: Two related patients aged 30 and 60 years, with MLVT and identified c.R345W mutation in the EFEMP1 gene, were tested. Mother and daughter showed a variable phenotype with reduced vision function in the younger patient, whereas the mother had a 'form frustre'. Fd-OCT revealed extensive or focal sub-retinal pigment epithelium (RPE) deposits, separation of RPE and Bruch's membrane, and disruption of the photoreceptor outer and inner segment layers. No outer retinal changes were visible outside areas with sub-RPE deposits. CONCLUSION: Retinal structure in EFEMP1 retinal dystrophy is reflected by morphological changes within the RPE/Bruch's membrane complex with accumulation of sub-RPE material associated with disrupted photoreceptor integrity. The pattern of microstructural retinal abnormalities is similar but with a different extent in patients with variable phenotypes.

Simultaneous imaging of human cone mosaic with adaptive optics enhanced scanning laser ophthalmoscopy and high-speed transversal scanning optical coherence tomography.

We describe a novel instrument capable of acquiring, simultaneously, adaptive optics enhanced scanning laser ophthalmoscopy and optical coherence tomography (OCT) images of the human cone mosaic in vivo. The OCT system is based on transversal scanning of the sample with a line scan rate of 14 kHz, approximately 20 times faster than a previously reported instrument. We demonstrate the capability of this instrument with the measurement of the human cone spacing in perifoveal retina.

Real-time assessment of retinal blood flow with ultrafast acquisition by color Doppler Fourier domain optical coherence tomography.

We interfaced color Doppler Fourier domain optical coherence tomography (CD-FDOCT) with a commercial OCT system to perform in vivo studies of human retinal blood flow in real time. FDOCT does not need reference arm scanning and records one full depth and Doppler profile in parallel. The system operates with an equivalent A-scan rate of 25 kHz and allows real time imaging of the color encoded Doppler information together with the tissue morphology at a rate of 2-4 tomograms (40 x 512 pixel) per second. The recording time of a single tomogram (160 x 512 data points) is only 6,4ms. Despite the high detection speed we achieve a system sensitivity of 86dB using a beam power of 500microW at the cornea. The fundus camera allows simultaneous view for selection of the region of interest. We observe bi-directional blood flow and pulsatility of blood velocity in retinal vessels with a Doppler detection bandwidth of 12.5 kHz and a longitudinal velocity sensitivity in tissue of 200microm/s.

Results of total deafness treatment in young pre- and postlingually deafened children.

Developing a cochlear implant program is one of the most difficult problems we need to solve concerning young children. Application of cochlear implants to this group of patients gives hope for better speech and language development than using conventional hearing aids. Children comprise approximately 40% of all implanted patients at the Institute of Physiology and Pathology of Hearing in Warsaw. They are provided with different types of cochlear implants, 16 of which are included in the international comparative study EARS (Evaluation of Auditory Responses to Speech). In this paper results are presented of auditory speech perception in pre-, peri-and postlingual children using the multichannel cochlear implant systems COMBI 40 and 40+. All the children were regularly evaluated following the EARS procedure with a number of perception tests. Monitoring of auditory perception development is fundamental and allows prognosis of speech and language development in children.

Numerical dispersion compensation for Partial Coherence Interferometry and Optical Coherence Tomography.

Dispersive samples introduce a wavelength dependent phase distortion to the probe beam. This leads to a noticeable loss of depth resolution in high resolution OCT using broadband light sources. The standard technique to avoid this consequence is to balance the dispersion of the sample byarrangingadispersive materialinthereference arm. However, the impact of dispersion is depth dependent. A corresponding depth dependent dispersion balancing technique is diffcult to implement. Here we present a numerical dispersion compensation technique for Partial Coherence Interferometry (PCI) and Optical Coherence Tomography (OCT) based on numerical correlation of the depth scan signal with a depth variant kernel. It can be used a posteriori and provides depth dependent dispersion compensation. Examples of dispersion compensated depth scan signals obtained from microscope cover glasses are presented.

First auditory brainstem implantation in Poland: auditory perception results over 12 months.

Auditory brainstem implants (ABIs) are a modern method of treatment of total bilateral deafness in cases of extracochlear origin. In most cases therapy is applied in patients with neurofibromatosis type 2 (NF2). This paper presents the results of surgical treatment and rehabilitation in a 28-year-old woman with bilateral, multiple tumours of the central nervous system causing total deafness. Simultaneous removal of the tumours and implantation of ABI allowed treatment of the potentially lethal pathology and hearing restoration. Improving auditory skills and excellent tests results were noted in the year following implantation.

Effects of pediatric HIV infection and prenatal drug exposure on mental and psychomotor development.

Examined the effects of HIV infection and prenatal drug exposure on infant neurodevelopmental functioning. Three groups of infants were compared: HIV-infected infants, seroreverters, and a comparison group who were prenatally exposed to drugs, but not HIV. Two thirds of the HIV-infected and seroreverter infants were prenatally drug-exposed. Infants (ages 4-30 months) were administered the Bayley Scales of Infant Development. Children who were both HIV-infected and prenatally drug exposed performed significantly lower on both the mental and psychomotor scales of the Bayley. Drug exposure and neurological dysfunction were associated with mental development, whereas neurological dysfunction, drug exposure, and HIV status were associated with psychomotor development.

Cognitive assessment of human immunodeficiency virus-exposed children.

OBJECTIVE: To determine (1) the level of impairment in cognitive and motor functioning in human immunodeficiency virus (HIV)-exposed and HIV-infected preschool and school-age children; (2) cognitive strengths and weaknesses that characterize HIV-infected children; and (3) potential contributions of serostatus, neurologic impairment, and prenatal drug-exposure to cognitive functioning. DESIGN: Cross-sectional, single-blind study. SETTING: Pediatric neurology clinic at a large metropolitan hospital in New York, NY. PARTICIPANTS: Forty-one HIV-infected and eight seroreverter school-age children. INTERVENTIONS: The McCarthy Scales of Children's Abilities were administered to all children, as was the Neurologic Examination for Children. MEASUREMENTS/MAIN RESULTS: The obtained mean of the sample on the McCarthy Scales' General Cognitive Index was in the Borderline range, with 44% of the subjects scoring in the Mentally Retarded range. The most severe cognitive deficits were found on the Quantitative, Verbal, and Memory scales (Borderline range). Children infected with HIV with neurologic impairment performed significantly worse than did seroverters and neurologically normal HIV-infected children. There were no significant differences in cognitive functioning due to gender, ethnicity, and prenatal drug exposure. CONCLUSIONS: Cognitive deficits were detected in HIV-infected and seroreverted children. The presence of neurologic dysfunction in HIV-infected children markedly intensified these deficits.