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Three years after receiving a Baerveldt tube implant for neovascular glaucoma, a 50-year-old man presented to the Wills Eye Hospital Glaucoma Service with pain and decreased vision in his left eye. On examination, a 4-0 nylon ripcord suture was seen to have migrated posteriorly through the pupil and in front of the intraocular lens. The distal end of the suture was not seen on dilated indirect ophthalmoscopic examination or by standard B-scan ultrasonography. Ultrasound biomicroscopy examination was performed, and the distal end of the suture was found to lie just anterior to the pars plana. Careful removal of the suture was performed intraoperatively through two paracentesis incisions using Kelman forceps. Posterior ripcord migration is a rare complication after glaucoma drainage implant surgery, and ultrasound biomicroscopy imaging may be helpful in determining its proper management.  相似文献   
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Background: Magnetic resonance neurography (MRN) is an imaging method by which nerves can be selectively highlighted. Using commercial software, the authors explored a variety of approaches to develop a three-dimensional volume-rendered MRN image of the entire brachial plexus and used it to evaluate the accuracy of infraclavicular block approaches.

Methods: With institutional review board approval, MRN of the brachial plexus was performed in 10 volunteer subjects. MRN imaging was performed on a GE 1.5-tesla magnetic resonance scanner (General Electric Healthcare Technologies, Waukesha, WI) using a phased array torso coil. Coronal STIR and T1 oblique sagittal sequences of the brachial plexus were obtained. Multiple software programs were explored for enhanced display and manipulation of the composite magnetic resonance images. The authors developed a frontal slab composite approach that allows single-frame reconstruction of a three-dimensional volume-rendered image of the entire brachial plexus. Automatic segmentation was supplemented by manual segmentation in nearly all cases. For each of three infraclavicular approaches (posteriorly directed needle below midclavicle, infracoracoid, or caudomedial to coracoid), the targeting error was measured as the distance from the MRN plexus midpoint to the approach-targeted site.

Results: Composite frontal slabs (coronal views), which are single-frame three-dimensional volume renderings from image-enhanced two-dimensional frontal view projections of the underlying coronal slices, were created. The targeting errors (mean +/- SD) for the approaches-midclavicle, infracoracoid, caudomedial to coracoid-were 0.43 +/- 0.67, 0.99 +/- 1.22, and 0.65 +/- 1.14 cm, respectively.  相似文献   

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The Stiles-Crawford effect of the first kind (SCE-I) was measured on both emmetropic and myopic subjects at six different retinal locations. The results revealed a number of significant discrepancies in receptor alignment between the groups of different refractive errors. In myopic subjects, the receptors in the nasal retina (i.e. between the fovea and the optic nerve head) were found to be aligned nasally towards the optic nerve head, whereas the receptors in the temporal retina were aligned towards the centre of the exit pupil. In emmetropic subjects, the receptors across the retina were finely tuned towards the centre of the exit pupil. The magnitude of the receptor displacement in myopic subjects was found to be directly associated with the length of the eyeball.  相似文献   
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This study compared the involvement of 28 mothers and their spouses in day care centers serving infants and toddlers. The sample consisted of parents who work at varying distances from the center. Parents were interviewed ten times each to determine the amount of time they spend in the center, frequency of communication with care providers, mid-day visits to the center, playing with the child, and holding the child in the center. Factor analysis reduced these variables to one parental involvement factor. Mothers were significantly more involved than fathers in the center, after statistically controlling for distance to the workplace and occupational status.  相似文献   
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