A HUMAN AND IN VITRO STUDY ON THE EXCHANGE OF WATER AND SOLUTES FROM SOFT CONTACT LENSES
| Autor: | F T Jensen, J Marqversen, Thorkild I. A. Sørensen |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
medicine.medical_specialty
Pertechnetate medicine.medical_treatment chemistry.chemical_element Human study In Vitro Techniques Sodium Chloride Technetium law.invention chemistry.chemical_compound Leucine law medicine Humans In vitro study Radionuclide imaging Radionuclide Imaging Saline Chromatography Chemistry Lacrimal Apparatus Water General Medicine Contact Lenses Hydrophilic Surgery Solutions Contact lens Lens (optics) Ophthalmology Radioactivity Conjunctiva |
| Zdroj: | Acta Ophthalmologica. 58:576-587 |
| ISSN: | 1755-375X |
| Popis: | Elimination of technetium (pertechnetate in normal saline solution) was studied from various types of contact lenses placed on normal human eyes by means of computer assisted gamma camera using "region of interest technique" with the designated area corresponding to the conjunctival sac. An elimination 4 times slower was found from a highly hydrophilic lens (Scanlens) than from a HEMA-lens (Softlens), 0,5% min and 2.0% min, respectively. From an ultrathin lens (U3-Softlens) was eliminated 2.4% min. Hard lenses did not absorb the isotope. In a laboratory study the lenses were pre-soaked in pertechnetate, blotted and washed at 2 min intervals in 0.5 ml saline. By this procedure 3% min of the technetium was eliminated from Scanlens, 16% min from Softlens and 28%/min from a thin, therapeutic lens (Plano-T). The ratio Softlens/Scanlens was in the human study 4.0 and in the laboratory study 4.9. Radioactivity was very rapidly eliminated from CAB-lenses. A similar study was carried out with radioactive water. More than 100% min was eliminated in the first 10 min followed by a slower elimination from 10-20 min. Then an increased elimination was seen for a few min. This increased elimination was in repeated studies constantly found after 20 min. It was not found in the studies with technetium and labelled leucine. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text