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1.
Ophthalmic Plast Reconstr Surg ; 37(4): e148-e149, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34085990

RESUMEN

We present the case of a Caucasian woman with a histology-confirmed granuloma faciale of the tarsoconjunctival surface of the eyelid. A 66-year-old female patient presented with a 1-week history of painless left upper eyelid mass without history of allergy, trauma, or ocular surgery. There was an elevated well-demarcated flesh-colored lesion within the tarsus. Diagnosis was confirmed by history of wedge biopsy, which demonstrated a mixed inflammatory cell infiltrate on a background of fibrosis with subtle focal leucocytoclasis. The lesion was fully excised without evidence of recurrence at follow up. Granuloma faciale is a rare disease often misdiagnosed clinically. Our case report is the first-documented granuloma faciale on the tarsoconjunctival surface of the eyelid and could suggest alternative pathogenesis in granuloma faciale development. Awareness of granuloma faciale as a nonmalignant for differential for tarsal lesions is important for treating clinicians.


Asunto(s)
Dermatosis Facial , Neoplasias Cutáneas , Anciano , Biopsia , Párpados , Femenino , Granuloma/diagnóstico , Humanos , Recurrencia Local de Neoplasia
2.
Artículo en Inglés | MEDLINE | ID: mdl-21244983

RESUMEN

Conventional ultrasonic transducers cannot withstand high temperatures for two main reasons: the piezoelectric elements within them depolarize, and differential thermal expansion of the different materials within a transducer causes them to fail. In this paper, the design of a high-temperature ultrasonic thickness gauge that bypasses these problems is described. The system uses a waveguide to isolate the vulnerable transducer and piezoelectric elements from the high-temperature measurement zone. Use of thin and long waveguides of rectangular cross section allows large temperature gradients to be sustained over short distances without the need for additional cooling equipment. The main problems that had to be addressed were the transmission and reception of ultrasonic waves into and from the testpiece that the waveguides are coupled to, and optimization of the wave propagation along the waveguide itself. It was found that anti-plane shear loading performs best at transmitting and receiving from the surface of a component that is to be inspected. Therefore, a nondispersive guided wave mode in large-aspect-ratio rectangular strips was employed to transmit the anti-plane shear loading from the transducer to the measurement zone. Different joining methods to attach the waveguides to the component were investigated and experiments showed that clamping the waveguides to the component surface gave the best results. The thickness of different plate samples was consistently measured to within less than 0.1 mm. Performance at high temperatures was tested in a furnace at 730°C for 4 weeks without signal degradation. Thicknesses in the range of 3 to 25 mm could be monitored using Hanning windowed tonebursts with 2 MHz center frequency.

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