RESUMEN
BACKGROUND: The complex interaction between contact lens wear and therapeutic drug use can account for physical and physiological changes in contact lens tolerance as well as changes in lens appearance. METHODS/RESULTS: Selected therapeutic drug issues are reviewed and recommendations are provided to assist clinicians in choosing management strategies for lens and therapeutic agent selection. CONCLUSIONS: The efficacy of drug absorption, whether from topical application or systemic secretion into the tear film, depends on the nature and water content of the polymer, lens thickness, drug and tear volume, and on adnexal and environmental factors. The "reservoir effect" of drug absorption in hydrogel lenses has led to its application as a method of enhanced drug delivery to the cornea and anterior segment. This same property, however, can also lead to excessive contact time between drug and cornea, leading to exacerbation of topical drug side effects and toxicity reactions with some therapeutic agents. Systemic medications used concurrently with contact lenses may have adverse effects on the blink mechanism and associated contact lens metabolism as well as on aqueous tear production, with resulting dry eye symptomatology.
Asunto(s)
Lentes de Contacto , Quimioterapia , Ojo/efectos de los fármacos , Absorción , Córnea/metabolismo , Interacciones Farmacológicas , Ojo/metabolismo , HumanosRESUMEN
Extended wear has been an attractive modality for many contact lens wearers. Despite the associated benefits of convenience and comfort, however, there have been many physiological complications reported for hydrogel extended-wear lenses, and a lesser number for rigid gas-permeable extended-wear lenses. This review describes the physiological as well as the mechanical complications of extended-wear lenses, for both soft lens and rigid lens materials, including etiology, clinical presentation, and management strategies.
Asunto(s)
Lentes de Contacto de Uso Prolongado/efectos adversos , Úlcera de la Córnea/etiología , Conjuntivitis Alérgica/etiología , Enfermedades de la Córnea/etiología , Edema Corneal/etiología , Infecciones Bacterianas del Ojo/etiología , HumanosRESUMEN
A patient presented with fever, night sweats, generalized lymphadenopathy, cold agglutinin hemolytic anemia, and thrombocytopenia. Lymph node biopsy revealed a lymphoplasmacytic infiltrate sparing the cortical sinuses but associated with arborizing blood vessels. Epstein-Barr virus (EBV) DNA was demonstrated in tissue from an involved lymph node. These data suggest an association of EBV with a lymphoproliferative process that resembles angioimmunoblastic lymphadenopathy with dysproteinemia.
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Enfermedades Autoinmunes/microbiología , Proteínas de la Cápside , ADN Viral/análisis , Herpesvirus Humano 4/inmunología , Linfadenopatía Inmunoblástica/microbiología , Ganglios Linfáticos/microbiología , Antígenos Virales , Enfermedades Autoinmunes/inmunología , Southern Blotting , Antígenos Nucleares del Virus de Epstein-Barr , Estudios de Seguimiento , Humanos , Linfadenopatía Inmunoblástica/inmunología , Ganglios Linfáticos/inmunología , Masculino , Persona de Mediana EdadRESUMEN
We describe the unique association of an aggressive prolactin secreting pituitary microadenoma invading through the sphenoid sinus with an empty sella, in which the pituitary tumor remained clinically undiagnosed. The postmortem anatomy of this empty sella syndrome is presented. It is concluded that the phrase "empty sella", although universally accepted, correlates poorly with the underlying disease, and that terms such as "intrasellar arachnoidocele" or "intrasellar subarachnoid herniation" would be more properly descriptive.
Asunto(s)
Síndrome de Silla Turca Vacía/complicaciones , Neoplasias Hipofisarias/complicaciones , Prolactinoma/complicaciones , Síndrome de Silla Turca Vacía/patología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Prolactinoma/patologíaRESUMEN
Many practitioners have long been frustrated with traditional treatments of symptomatic latent hyperopia (fogging techniques, bifocals, etc.). A technique employing short-acting cycloplegia has been developed which provides rapid relief of symptoms by promoting full correction of latent refractive error. Fifteen symptomatic subjects ages 3-40 were diagnosed as latent hyperopes with the aid of 1% cyclopentolate, and subsequently recyclopleged utilizing full correction in constant wear spectacles. Acuity was maintained via slow diminution of cycloplegia. Short-term and long-term follow-up, with continued use of spectacles or contact lenses, revealed rapid and complete resolution of symptoms and restoration of visual efficiency in each case. Cyclotherapy offers both practitioners and patients an efficient, rapid-acting, and satisfying alternative treatment for this vexing accommodative anomaly.
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Hiperopía/tratamiento farmacológico , Midriáticos/uso terapéutico , Acomodación Ocular , Adolescente , Adulto , Niño , Preescolar , Humanos , Hiperopía/diagnóstico , Hiperopía/patología , Hiperopía/fisiopatología , Midriáticos/efectos adversos , Refracción Ocular , Retina/patología , Pruebas de VisiónRESUMEN
The use of microcomputers, although increasingly common in the clinical laboratory, is not problem- or risk-free. Some of these problems and risks are discussed in this article and suggestions for minimizing them are offered. Forewarned is forearmed. The author hopes that pointing out the risks and deficiencies of microcomputers will promote their intelligent application in the clinical laboratory.
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Computadores , Departamentos de Hospitales , Microcomputadores , Servicio de Patología en Hospital , Toma de Decisiones , Humanos , Estados UnidosRESUMEN
Protein-free red blood cells were prepared by washing fresh citrate-phosphate-dextrose anticoagulated whole blood and resuspending the cells in a medium containing saline, adenine, phosphate, and glucose (APG). The protein concentration in the APG medium was reduced to 0.0024 percent of the original plasma protein. The 24-hour red blood cell posttransfusion survival after 21 days of storage was 80 percent. Extracellular potassium concentrations were less than the CPD-plasma control after 21 days of storage. Adenosine triphosphate (ATP) concentrations were lower after storage in APG, but intracellular ATP was not closely associated with posttransfusion survival. Hemolysis was slightly increased in the APG group. There appear to be no insurmountable barriers to the use of protein-free media for the storage of washed red blood cells.
Asunto(s)
Conservación de la Sangre/métodos , Proteínas Sanguíneas/análisis , Envejecimiento Eritrocítico/efectos de los fármacos , Adenina/farmacología , Adenosina Trifosfato/sangre , Anticoagulantes/farmacología , Citratos/farmacología , Glucosa/farmacología , Humanos , Fosfatos/farmacologíaRESUMEN
To determine the current risk of hepatitis B virus (HBV) infection in multiply transfused thalassemia patients, we tested sera from such patients in New York City for the hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs) using radioimmunoassay techniques. Altogether 48 per cent of the patients had either HBsAg (4.5%) or anti-HBs (43.9%) positive sera. The prevalence of these HBV markers was related to both the number of units transfused and the year blood transfusion therapy was begun, although evidence suggested that the latter factor had the greatest influence. Donor HBsAg screening began in New York in 1969, and only one patient first transfused since that time had HBV marker positive serum. Thus, multiply-transfused thalassemia patients now appear to be at little risk of HBV infection from transfusions. Sera were also tested for antibody to the hepatitis A virus (anti-HA) using immune adherence hemaglutination. Anti-HA prevalence was only 4.9 per cent, no greater than rates reported among nontransfused children, providing evidence against a significant role for blood transfusions in hepatitis A virus transmission.