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B Bachynski

Publications and source records attributed to B Bachynski.

8 recordsLinked to original sources
PubMed1992

A cohort study of transcutaneous oxygen tension and the incidence and severity of retinopathy of prematurity.

BACKGROUND: Retinopathy of prematurity is a disease affecting the blood vessels of the retina in premature infants that may result in scarring, retinal detachment, and loss of vision. An association between this condition and the exposure of premature infants to supplemental oxygen has been postulated, but the relation between retinopathy of prematurity and blood oxygen levels has not been defined. The purpose of this study of a cohort of preterm infants was to correlate the incidence and severity of retinopathy of prematurity with the duration of exposure to different ranges of oxygen tension as measured by transcutaneous monitoring (tcPO2). METHODS: One hundred one premature infants (birth weight, 500 to 1300 g) requiring supplemental oxygen had continuous monitoring of tcPO2. The number of hours during which the tcPO2 was 80 mm Hg or higher was tabulated for each infant during the first four weeks of life. RESULTS: There was a significant association between the amount of time that the tcPO2 was greater than or equal to 80 mm Hg and the incidence and severity of retinopathy of prematurity. The odds ratio for each 12-hour period in which the tcPO2 was greater than or equal to 80 mm Hg was 1.9 (95 percent confidence interval, 1.2 to 3.0) after adjustment for the following factors: birth weight less than or equal to 1300 g (odds ratio, 2.3 [95 percent confidence interval, 1.6 to 3.4]), five-minute Apgar score of 7 or less (odds ratio, 7.2 [95 percent confidence interval, 2.5 to 21]), and exposure to inspired oxygen at a concentration greater than or equal to 0.4 (odds ratio, 1.0 [95 percent confidence interval, 0.97 to 1.05]). The association was stronger for tcPO2 values of greater than or equal to 80 mm Hg occurring from the second through the fourth week of life; during this period, the adjusted odds ratio for a 12-hour period of such exposure was 3.1 (95 percent confidence interval, 1.6 to 6.1). CONCLUSIONS: This study supports an association between the incidence and severity of retinopathy of prematurity and the duration of exposure to arterial oxygen levels of 80 mm Hg or higher, measured transcutaneously.

Apgar Score↗
PubMed1989

Molecular genetics of human blue cone monochromacy.

Blue cone monochromacy is a rare X-linked disorder of color vision characterized by the absence of both red and green cone sensitivities. In 12 of 12 families carrying this trait, alterations are observed in the red and green visual pigment gene cluster. The alterations fall into two classes. One class arose from the wild type by a two-step pathway consisting of unequal homologous recombination and point mutation. The second class arose by nonhomologous deletion of genomic DNA adjacent to the red and green pigment gene cluster. These deletions define a 579-base pair region that is located 4 kilobases upstream of the red pigment gene and 43 kilobases upstream of the nearest green pigment gene; this 579-base pair region is essential for the activity of both pigment genes.

Adolescent↗
PubMed1986

Fatal metabolic acidosis, hyperglycemia, and coma after steroid therapy for Kearns-Sayre syndrome.

Two adolescent boys with Kearns-Sayre syndrome (progressive external ophthalmoplegia, heart block, elevated CSF protein, and ragged-red muscle fibers) developed lethargy, increasing somnolence, polydipsia, polyphagia, and polyuria after a brief course of steroid therapy. Both had hyperglycemia and acidosis. Nonketotic, lactic acidosis was present in one and ketosis in the other. Severe respiratory failure developed, and both patients died. Postmortem revealed fatty infiltration of the pancreas in addition to a diffuse spongiform encephalopathy.

Acidosis↗
PubMed1986

Telangiectatic osteosarcoma: unusual behaviour.

The telangiectatic variant of osteogenic sarcoma is rare. Its biologic behaviour, treatment and prognosis are controversial. The case of a 15-year-old girl with this tumour is described. Both the location and clinical behaviour of the tumour were unusual. The tumour, which involved the distal ulna, was initially treated by a limited resection of the distal 8 cm of ulna. Sixty-nine months later the tumour recurred locally; there was no evidence of metastases. The forearm was amputated and the patient was then treated aggressively by chemotherapy. She was well 42 months later. This case illustrates the tendency for telangiectatic osteosarcoma to recur locally if it is not radically excised.

Adolescent↗
PubMed1984

Cogan's syndrome: a treatable cause of neurosensory deafness.

Cogan's syndrome, nonsyphilitic interstitial keratitis associated with vestibuloauditory deficits, can vary in its presentation. This paper describes an unusual case in which deafness developed while the patient was receiving topical therapy with prednisolone and homatropine for mild bilateral iritis and right-sided nodular episcleritis. The 10-year-old boy's hearing improved dramatically with high-dose systemic steroid therapy. The importance of being aware that deafness may occur in children undergoing treatment for "routine" iritis is emphasized.

Child↗
PubMedDate not supplied

A new VEP system for studying binocular single vision in human infants.

Visual evoked potentials (VEPs), that provide unequivocal objective evidence of cortical binocularity have been recorded from adults and young infants using a new VEP system developed for this purpose. The system uses alternating field stereoscopy (AFS) to present separate visual stimuli to each eye. With this system, the binocular image pairs to the right and left eyes alternate at a high rate on a single video monitor. The subject wears spectacles incorporating light-scattering liquid crystal lenses which alternate electronically between opaque and clear modes in synchrony with the video monitor. To detect cortical binocularity, the system analyzes VEP activity mathematically and identifies significant responses at test frequencies reflecting binocular cortical interactions exclusively. Three types of binocular stimuli were presented: (1) dynamic random dot correlograms (correlograms); (2) dynamic random dot stereograms (stereograms); and (3) dichoptic checkerboard stimuli. The correlograms are generated when moving random dot patterns presented to each eye alternate between two phases, correlated and anticorrelated. With the stereograms, portions of random dot patterns presented to each eye are shifted horizontally relative to each other at a fixed rate, alternately producing crossed and uncrossed binocular disparities. Subjectively, these patterns appear to shift in depth. Dichoptic checkerboard stimuli are regular checkerboard patterns which reverse at different rates (frequencies) for each eye. Binocular VEPs are generated due to cortical interactions at the difference (beat) frequency. Using this VEP system, we have recorded binocular VEPs from 10 normal adults and more than 40 infant subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗