Partial Opacification Research Articles

Effect of Therapeutic Ultrasound on Intraocular Lenses

High intensity, focused ultrasound energy is currently being evaluated as a therapy for glaucoma. The energy is delivered through conjunctiva and sclera to the pars plicata. The haptics of intraocular lenses may erode into the pars plicata, and we were therefore prompted to study the effects of ultrasound energy on intraocular lenses. The energy is highly absorbed by polymethylmethacrylate (PMMA), resulting in partial melting, vacuolization, and opacification of this material at intensities much lower than those used in the glaucoma treatment. Polypropylene absorbed much less of the energy, resulting in relatively minor morphologic changes with this material. We recommend caution in using this device in eyes with anterior chamber intraocular lenses and eyes with posterior chamber intraocular lenses having PMMA haptics.

Maxillary Sinus Radiographs in Children with Nonrespiratory Complaints

An attempt was made to determine the frequency of abnormal maxillary sinus radiographs in a group of unselected children having diagnostic skull radiographs performed for indications unrelated to respiratory infection. An occipitomental, or Water's, view was obtained in every case in order to evaluate the maxillary sinuses. Prior to performance of the radiographs, a history of recent respiratory symptoms was obtained and a physical examination of the ears, nose, and throat was performed. An abnormal maxillary sinus radiograph was defined as one that revealed an air-fluid level, partial or complete opacification, or mucous membrane thickening of 4 mm or greater. Fifty-nine (53%) of 112 presumably "normal" children had evidence of recent respiratory inflammation by history or at physical examination. In 50 subjects less than 1 year of age, abnormal maxillary sinus radiographs were common, irrespective of respiratory symptoms and signs. In contrast, eight of 14 children (57%) aged 1 to 16 years with both symptoms and signs of respiratory inflammation had abnormal maxillary radiographs, compared with only two of 31 children (7%) with neither symptoms nor signs (P less than .005). Crying alone was not associated with abnormal radiographs in the older age group. In children more than 1 year of age, abnormal maxillary sinus radiographs are infrequent and are generally related to inflammation of the upper respiratory tract.

Sonographic evaluation of the chest in infants and children.

Sonography was used to evaluate 28 patients (age range, newborn to 16 years) with mediastinal and juxtacardiac masses and disease processes, partial or complete opacification of a hemithorax, and various juxtadiaphragmatic abnormalities. Technically adequate studies were obtained in 93% of the cases. Sonography was of greatest value in determining the cause of an opaque hemithorax, characterizing fluid collections, localizing fluid collections prior to percutaneous aspiration or drainage, and demonstrating the position and integrity of the diaphragm. Sonography was least successful in depicting and characterizing mediastinal disorders. The authors' method is described and the technical limitations and pitfalls of pediatric chest sonography are discussed.