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1.
Ophthalmol Retina ; 2(6): 613-622, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-31047615

RESUMEN

OBJECTIVE: Optical coherence tomography angiography (OCTA) is a new, noninvasive imaging modality used to assess the vasculature in chorioretinal disease. The purpose of this study was to describe OCTA findings in several chorioretinal tumors, specifically melanocytic tumors. We correlate these findings with clinical risk factors (RFs) for growth. STUDY DESIGN: This was a cross-sectional, comparative, observational study. SUBJECTS: We compiled a total of 79 cases consisting of the following: 55 choroidal nevi, 11 choroidal melanomas, 5 choroidal hemangiomas, 3 astrocytic hamartomas, 2 choroidal lymphomas, 1 choroidal metastases, 1 combined hamartoma of the retina and retinal pigment epithelium (RPE), and 1 choroidal osteoma. METHODS: We performed OCTA of the 79 lesions to create images that were then analyzed by 3 different physicians. In addition to OCTA, we also used multi-imaging studies, including OCT, retinal color and autofluorescence fundus imaging, Doppler echography, and indocyanine/fluorescein angiography. The melanocytic lesions were divided into 6 different groups according on the number of clinical RFs present. We compared each group with the OCTA findings, seeking any correlation between OCTA findings and the number of RFs present. OUTCOME MEASURES: All layers of the OCTA were evaluated and described. In melanocytic lesions, 6 specific variables within the choriocapillaris layer were evaluated. We also studied the quality of the images, the presence of avascular areas within the lesion, heterogeneity of the choroidal plexus over the lesion, the presence of a neovascular membrane associated with the lesion, the definition of the lesion's borders, and the presence of a hyperreflective ring surrounding the lesion. RESULTS: Satisfactory imaging was obtained in 82.7% of the cases. Concordance κ indexes between the observers were satisfactory (0.768-0.958). For melanocytic lesions, the images of choroidal nevi were described mainly as heterogenic (61.4%) and hyperreflective (81.8%). Choroidal melanoma was mainly described as isoreflective or hyporeflective (62.5%) and associated with a hyperreflective ring (62.5%). The presence of a hyporeflective plexus within the tumor (P = 0.002) and the presence of a hyperreflective ring surrounding the lesion (P = 0.001) were associated with lesions with more RFs. General descriptive OCTA findings are made for nonmelanocytic tumors. CONCLUSION: OCTA is a very promising new technology that can be used in the study of posterior segment ocular tumors. When studying melanocytic tumors, the presence of a hyporeflective plexus or hyperreflective ring (in the choriocapillaris layer) surrounding the tumor is associated with a higher risk of malignancy. Larger studies are needed to corroborate these findings. However, we hope that these data can encourage more regular screening for those detected to be at high risk and, hence, reduce the risk of malignancies detected at a late stage.

2.
J Sports Med Phys Fitness ; 58(6): 761-767, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29877679

RESUMEN

BACKGROUND: The purpose of the present research was to analyze the modifications on aerobic swimming performance indicators after performing traditional and reverse training periodizations (TTP and RTP, respectively). METHODS: Seventeen trained swimmers were divided into two groups: one group (N.=7) performed 10 weeks of TTP (based on high volumes and an increased intensity during the program) and the second one (N.=10) was involved in a similar period of RTP (based on low volumes and high intensity during the entire program). Velocity (v), heart rate (HR) and rate of perceived exertion (RPE) at the intensity of 4 mmol/L of blood lactate concentration, v, HR, RPE, stroke rate, stroke length and stroke index at the minimal intensity that elicits maximal oxygen uptake (vVO2max) and maximal oxygen uptake (VO2max) were analyzed pre- and post-training intervention. RESULTS: Stroke index significantly increased (2.9±0.3 vs. 3.1±0.2; P<0.05) and stroke rate and RPE at vVO2max significantly decreased after performing TTP. In the RTP group, VO2max significantly increased (50.9±6.6 vs. 54.1±4.7 mL/min/kg). CONCLUSIONS: In conclusion, RTP performed for 10 weeks was more effective than TTP to increase the VO2max in trained swimmers, but TTP yields a higher swimming efficiency, probably due to the higher volume of technical training performed during the training program.


Asunto(s)
Rendimiento Atlético/fisiología , Prueba de Esfuerzo , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Acondicionamiento Físico Humano/fisiología , Natación/fisiología , Adolescente , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno , Resistencia Física , Esfuerzo Físico
3.
J Ophthalmol ; 2017: 1573154, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29201456

RESUMEN

OBJECTIVE: To describe OCTA findings in choroidal melanocytic tumors, especially the microcirculation patterns, and to try to correlate with the histopathological studies. METHODS: Cross-sectional, comparative, observational study. 70 cases, including 55 choroidal nevi and 15 choroidal melanomas. Three different observers evaluated specific variables in the choriocapillaris layer on AOCT images and searched for images which described histopathologic vascular patterns, and also, a general description of the images was made. Complementary multi-imaging studies included EDI SD-OCT, color and autofluorescence fundus imaging, Doppler ultrasound, and indocyanine/fluorescein angiography. MAIN RESULTS: Good quality studies were acquired in 80% of the cases, with kappa indexes 0.768-0.958. Nevus OCTA images were described mainly as hyperreflective (72.7%), whereas choroidal melanoma as iso/hyporeflective (62.5%). Avascular areas were found in 50.96% and in 33.3% of choroidal nevus and choroidal melanomas, respectively. A neovascular membrane was found only in cases of choroidal nevus (16.3%). Only in cases of choroidal melanomas, we found vascular loops (6.6%) or vascular networks (6.6%). CONCLUSION: OCTA is a promising new technology that can be used to study in vivo the differential characteristics of microcirculations between posterior segment melanocytic lesions. Today, larger studies are needed to corroborate these findings and to correlate it with malignancy.

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