The specific causes of blepharospasm and apraxia of lid opening are unknown, but these two conditions coexist in some patients and can be difficult to treat. It is important to make a correct diagnosis, and a combined surgical and botulinum toxin treatment can be very effective.
Fifty clinically indicated vacuum extractions were studied to evaluate a possible relationship between neurobehavioral abnormality, retinal hemorrhages and the tractive force used for delivery. A Vacuum Extractor Recorder (Type SF 30, Knick), was used to measure the forces necessary for delivery of the head. Infants delivered by the use of extensive tractive force showed no greater incidence of neuropathology than those delivered with less tractive force. The retinal hemorrhages were equally distributed among the infants, irrespective of the tractive force applied or the neurobehavioral assessment. The implication is that retinal hemorrhages cannot be used to evaluate the extent of cerebral influence after birth and that the main cause of neurobehavioral abnormality is the condition leading to the use of the vacuum extractor (VE).
Fetal head compression pressure (FHCP) and its clinical importance has been investigated in a group of 46 spontaneous births. Measurement of FHCP was facilitated using a compression transducer positioned between the fetal head and the wall of the birth canal. This method not only constitutes a means of quantitating the forces acting directly on the fetal head, but also provides information about the intracranial pressure generated during delivery. The latter extrapolation is based on the principle of applanation. The technique provides an objective and reliable estimate of intracranial strain and therefore a means of comparing the forces generated under different delivery modes. The condition of the same neonates at birth was assessed using umbilical artery pH, Apgar score, neurobehavioral testing and fundoscopic examination. The mean amplitude of FHCP in the different deliveries ranged from 38 to 390 mmHg (5-52 kPa) with an overall mean of 157.9 mmHg (21.1 kPa). The study indicated that the appearance of retinal hemorrhages in the newborn cannot be explained by exposure of the fetal head to abnormally high compression during birth. Other explanations must be sought for infants with a neurobehavioral deficit, reduced Apgar score, or umbilical artery acidosis at birth. It is concluded that a relatively short period of high FHCP has no obvious consequences for fetal well-being, at least within the limits described in the present report.
The epithelium was removed from human corneas, and samples of conjunctival tissue were cultured as explants on the denuded corneal surface for 1 and 2 weeks. Cells migrating from the conjunctival explants onto the corneal surface produced a multilayer where cells on the surface generally showed a flattened appearance. The apical membrane of these cells demonstrated villi as well as microplicae. Surface projections were also detected on cells in the deeper layers of the epithelium. Neighbouring cells were connected by junctional complexes. After 2 weeks, however, a lack of intercellular junctions in some areas resulted in the formation of intraepithelial cystoid spaces. Basal cells were connected to the underlying basement membrane by hemidesmosomes. Although transdifferentiation of the cells into a corneal epithelium was not observed within the 2 weeks, the present system provides a tool for studies on factors affecting reepithelialization of corneal epithelial defects by conjunctival cells.
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