Bilateral keratectasia after photorefractive keratectomy.

PURPOSE: To report the clinical features, management, and outcome of a patient who developed bilateral ectasia after photorefractive keratectomy (PRK). METHODS: Case report of a 35-year-old man who underwent bilateral PRK. Preoperative uncorrected visual acuity was 20/200 in the right eye and 20/100 in the left eye. The patient's history was unremarkable and he denied a family history of ocular disorders. RESULTS: Two weeks after surgery, the patient presented with loss of visual acuity in both eyes. Uncorrected visual acuity was 20/80 in the right eye and 20/200 in the left eye. Objective refraction could not be obtained. Slit-lamp microscopy showed corneal thinning in both eyes. After examining the patient's family, his sister was found to have clinical and topographic keratoconus. CONCLUSIONS: Ectasia is a rare complication of PRK. We report the occurrence of bilateral ectasia after PRK in a patient with asymmetric bowtie topographies. We recommend that refractive surgery, even surface techniques such as PRK, be avoided in patients with a family history of keratoconus.

[Correlation between left ventricular ejection fraction assessed by gated SPECT and radionuclide ventriculography in patients with ischemic cardiomyopathy]. / Correlación entre la fracción de expulsión obtenida con SPECT sincronizado y ventriculografía con radionúclidos en pacientes con cardiopatía isquémica.

BACKGROUND: Recently, the use of Gated SPECT to assess ejection fraction, volumes and ventricular wall motion has been suggested. The aim of this study is to compare the ejection fraction (EF) obtained by Gated SPECT (QGS, Cedars Sinai) with the values obtained through equilibrium ventriculography in patients with ischemic heart disease. METHODS: We studied 50 consecutive patients that were diagnosed by equilibrium radioisotopic ventriculography and Gated SPECT with a dual protocol (TI-201 rest/Tc-99m SestaMIBI stress) using the QGS, Cedars Sinai software. RESULTS: We found a 92% correlation between both tests. In the subgroup analysis, the higher correlation (r = 0.89) was found in group 2, which included patients with moderate ventricular dysfunction (EF 30-50%), whereas, in patients with severe ventricular dysfunction (group 3, EF < 30%), the correlation was lower (r = 0.76) than in group 2, but higher than in patients with EF > 50% (group 1). CONCLUSIONS: There is a good correlation between EF obtained with Gated SPECT and equilibrium ventriculography, regardless of the EF value.

Technetium-99m-Sestamibi SPECT myocardial perfusion imaging in patients with complete left bundle branch block.

BACKGROUND: Diagnosis of coronary artery disease (CAD) in patients with left bundle branch block (LBBB) is considered a challenge in cardiology due to low accuracy of noninvasive methods such as basal and exercise stress test. Recently, myocardial perfusion imaging showed attainment of higher sensitivity and specificity. Scintigraphy with thallium-201 has been widely used in these patients. Few have used technetium-99m-Sestamibi and single photon emission computed tomography (SPECT). The aim of the study was to assess the diagnostic value of Tc-99m Sestamibi SPECT myocardial perfusion imaging in patients with complete LBBB. METHODS: We studied 57 consecutive patients with complete LBBB using Tc-99m-Sestamibi SPECT and treadmill or dipyridamole stress to evaluate CAD. Eighteen patients also underwent coronary angiography. Perfusion defects were classified as fixed or reversible. RESULTS: Prevalence of resting perfusion abnormalities in anterior, septal, and apical regions was 51, 56, and 19%, respectively. Sensitivity for detecting >50% left anterior descending artery (LAD) stenosis was 67 and 56% for anterior or septal defects, and 56% for specificity. Apical perfusion abnormality showed 21% sensitivity and 89% specificity. Among six patients with reversibility and who underwent coronary angiography, all had >50% LAD stenosis. CONCLUSIONS: With Tc-99m-MIBI SPECT imaging, prevalence of anteroseptal perfusion abnormalities was >50% in patients with LBBB. The test has moderate sensitivity and specificity for LAD disease. Absence of apical defect is specific for excluding LAD disease. Reversible changes in anteroseptal wall should be considered as an indicator of ischemia in this territory.

Correlación entre la fracción de expulsión obtenida con SPECT sincronizado y ventriculografía con radionúclidos en pacientes con cardiopatía isquémica / Correlatin betweeen left ventricular ejection fraction assessed by gated spect and radionuclide ventriculograhyy

Antecedentes : Recientemente se ha propuesto el empleo del SPECT sincronizado para la medición de fracción de expulsión, volúmenes y movilidad de la pared ventricular. El objetivo de este estudio es evaluar la fracción de expulsión (FE) obtenida con el programa de SPECT sincronizado (QGS, Cedars Sinai) en comparación con la ventriculografía en equilibrio en pacientes isquémicos. Método : Estudiamos 50 pacientes consecutivos con cardiopatía isquémica, a los cuales se les realizó ventriculografía radioisotópica con la técnica de equilibrio in vitro modificada y SPECT sincronizado con un protocolo dual (Talio 201reposo/Tc-99m SestaMIBI esfuerzo) utilizando el programa QGS (Cedars Sinai). Resultados : Se observó una correlación del 92% entre los dos métodos. En el análisis por subgrupos, la correlación más alta (r = 0.89) se encontró en el grupo 2, que incluye a los pacientes con disfunción ventricular moderada (FE 30-50%), mientras que en los pacientes con disfunción ventricular severa (grupo 3, FE < 30%) se encontró una correlación menor (r = 0.76) que en el grupo 2, pero mayor que en los pacientes con FE > 50% (grupo 1). Conclusiones : Existe una buena correlación entre la FE del ventrículo izquierdo obtenida con el método de SPECT sincronizado y la ventriculografía en equilibrio, independientemente de la cifra de FE.

Background : Recently, the use of Gated SPECT to assess ejection fraction, volumes and ventricular wall motion has been suggested. The aim of this study is to compare the ejection fraction (EF) obtained by Gated SPECT (QGS, Cedars Sinai) with the values obtained through equilibrium ventriculography in patients with ischemic heart disease. Methods : We studied 50 consecutive patients that were diagnosed by equilibrium radioisotopic ventriculography and Gated SPECT with a dual protocol (Tl-201rest/Tc-99m SestaMIBI stress) using the QGS, Cedars Sinai software. Results : We found a 92% correlation between both tests. In the subgroup analysis, the higher correlation (r = 0.89) was found in group 2, which included patients with moderate ventricular dysfunction (EF 30-50%), wereas, in patients with severe ventricular dysfunction (group 3, EF < 30%), the correlation was lower (r = 0.76) than in group 2, but higher than in patients with EF > 50% (group 1). Conclusions : There is a good correlation between EF obtained with Gated SPECT and equilibrium ventriculography, regardless of the EF value. (Arch Cardiol Mex 2004; 74:25-30).