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1.
Neonatology ; 98(2): 137-42, 2010.
Article in English | MEDLINE | ID: mdl-20150751

ABSTRACT

BACKGROUND AND OBJECTIVES: To retrospectively analyze changes in incidence and risk factors of retinopathy of prematurity (ROP) over two periods, 10 years apart, in the central Netherlands. METHODS: Data of 570 infants admitted between 2001 and 2005, screened for ROP according to the Dutch National guideline, were compared to those of 538 infants admitted between 1991 and 1995. RESULTS: Incidence of ROP decreased significantly over the last decade (40.9% in 1991-1995 vs. 23.3% in 2001-2005, p < 0.001), together with incidence of severe ROP (stage >or=3) (3.3 vs. 1.2%, p < 0.05). In infants with a birth weight (BW) <1,000 g incidence of ROP dropped significantly (67.0 vs. 41.8%, p < 0.001), as well as incidence of severe ROP (8.1 vs. 3.0%, p < 0.05). For infants with a BW >or=1,000 g incidence of ROP also declined significantly (27.1 vs. 13.0%, p < 0.001), that of severe ROP remained unchanged (0.8 vs. 0.3%). In both periods gestational age, duration of artificial ventilation, small for gestational age (SGA) and postnatal steroids were independent risk factors for ROP. CONCLUSIONS: In the central Netherlands, incidence of ROP and severe ROP has significantly decreased, also in infants with BW <1,000 g. Risk factors remained unchanged.


Subject(s)
Retinopathy of Prematurity/epidemiology , Gestational Age , Humans , Incidence , Infant, Newborn , Infant, Premature , Infant, Very Low Birth Weight , Mass Screening , Netherlands/epidemiology , Retinopathy of Prematurity/diagnosis , Retrospective Studies , Risk Factors
4.
IEEE Trans Biomed Eng ; 41(12): 1136-46, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7851915

ABSTRACT

This paper describes a 3-D microelectrode array for the chronic recording of single-unit activity in the central nervous system. The array is formed by a microassembly of planar silicon multishank microprobes, which are precisely positioned in a micromachined platform that resides on the surface of the cortex. Interconnects between the probes and the platform are formed using electroplated nickel lead transfers, implemented using automated computer control. All dimensions are controlled to +/- 1 micron and sank/probe separations as small as 100 microns are possible. Four-probe 16-shank prototype arrays have been tested chronically in guinea pig cortex. After three months in vivo, no significant tissue reaction has been observed surrounding these structures when they remain free to move with the brain, with normal appearing tissue between shanks spaced at 150 microns to 200 microns intervals. The array structure is compatible with the use of signal processing circuitry both on the probes and on the platform. A platform-based signal processing system has been designed to interface with several active probes, providing direct analog access to the recording sites, performing on-chip analog-to-digital conversion of neural activity, and providing simple binary-output recognition of single-unit spike events using a user-input threshold voltage.


Subject(s)
Electrodes, Implanted , Microelectrodes , Signal Processing, Computer-Assisted/instrumentation , Animals , Biocompatible Materials , Cerebral Cortex/pathology , Electric Impedance , Electroencephalography/instrumentation , Equipment Design , Guinea Pigs , Microscopy, Electron, Scanning
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