Chalcogenide photonics: fabrication, devices and applications. Introduction.

Introduction to a focus issue of invited articles that review recent progress in chalcogenide photonics.

Progress in optical waveguides fabricated from chalcogenide glasses.

We review the fabrication processes and properties of waveguides that have been made from chalcogenide glasses including highly nonlinear waveguides developed for all-optical processing.

Three-dimensional endoscopic pituitary surgery.

OBJECTIVE: We describe a novel 3-dimensional (3-D) stereoendoscope and discuss our early experience using it to provide improved depth perception during transsphenoidal pituitary surgery. METHODS: Thirteen patients underwent endonasal endoscopic transsphenoidal surgery. A 6.5-, 4.9-, or 4.0-mm, 0- and 30-degree rigid 3-D stereoendoscope (Visionsense, Ltd., Petach Tikva, Israel) was used in all cases. The endoscope is based on "compound eye" technology, incorporating a microarray of lenses. Patients were followed prospectively and compared with a matched group of patients who underwent endoscopic surgery with a 2-dimensional (2-D) endoscope. Surgeon comfort and/or complaints regarding the endoscope were recorded. RESULTS: The 3-D endoscope was used as the sole method of visualization to remove 10 pituitary adenomas, 1 cystic xanthogranuloma, 1 metastasis, and 1 cavernous sinus hemangioma. Improved depth perception without eye strain or headache was noted by the surgeons. There were no intraoperative complications. All patients without cavernous sinus extension (7of 9 patients) had gross tumor removal. There were no significant differences in operative time, length of stay, or extent of resection compared with cases in which a 2-D endoscope was used. Subjective depth perception was improved compared with standard 2-D scopes. CONCLUSION: In this first reported series of purely 3-D endoscopic transsphenoidal pituitary surgery, we demonstrate subjectively improved depth perception and excellent outcomes with no increase in operative time. Three-dimensional endoscopes may become the standard tool for minimal access neurosurgery.

Label-free detection with the resonant mirror biosensor.

The resonant mirror (RM) biosensor is a leaky waveguide-based instrument that uses the evanescent field to probe changes in the refractive index at the sensing surface.The RM can therefore be used to monitor in real-time and label-free the interaction between an analyte in solution and its biospecific partner immobilized on the waveguide surface.The RM has been used in studying the interaction of a variety of moieties including proteins, carbohydrates, cells, nucleic acids and receptors, leading to applications in areas such as clinical diagnostics, homeland security, and pharmaceutical and biomolecular interactions. This chapter will review the principle of this biosensor, and the recent advances in instrumentation, different immobilization chemistries, and kinetic studies, as well as some applications.

Newly designed ergonomic surgical binocular telescope with angulated optic axis.

OBJECTIVE: Magnification by surgical loupes has the distinct merits of agility and nimbleness in observation, a wide stereo base effectuating superior depth sensation, and light augmentation by an objective lens that is larger than the pupil. However, continuous use of these loupes causes neck strain for surgeons as a result of flexion posture and fatigue. To minimize the strain and fatigue and maximize the advantages and performance of binocular telescopes, we have developed a novel optical design. METHODS: To allow observation of the operative field with the surgeon's neck and eye in a straight position, the light path of the telescopes was angulated downward with roof prisms. For maximum image quality, Keplerian real-image optics were adopted. RESULTS: The optics, finishing of the lens, and assembly were perfected through practical trials of more than 500 procedures over a period of 3 years. CONCLUSION: The new ergonomically designed optics provide excellent image quality comparable to standing microscopes in the low to medium range of magnification, while effectively reducing the neck flexion of surgeons working in the operative field below and relieving the surgeon's fatigue during hours of continuous use.

Concepts for nanoscale resolution in fluorescence microscopy.

Spatio-temporal visualization of cellular structures by fluorescence microscopy has become indispensable in biology. However, the resolution of conventional fluorescence microscopy is limited by diffraction to about 180 nm in the focal plane and to about 500 nm along the optic axis. Recently, concepts have emerged that overcome the diffraction resolution barrier fundamentally. Formed on the basis of reversible saturable optical transitions, these concepts might eventually allow us to investigate hitherto inaccessible details within live cells.

Contribuição para o tratamento da dislexia: o uso de lentes esfero-prismáticas na leitura / Contribution to the study of developmental dyslexia: the reading performance with prismatic lenses

O objetivo deste trabalho foi o de estudar a melhora no desempenho de leitura de crianças portadoras de Dislexia do Desenvolvimento utilizando lentes esfero-prismáticas. Foi realizado estudo tipo ensaio clínico. Do total de 300 pacientes com diagnóstico já estabelecido foram selecionados 52 para o grupo controle e 78 para o grupo experimental. Nos dois grupos foi testado o uso de lentes esfero-prismáticas. Os resultados mostraram que houve benefício com o uso deste auxílio óptico /The object of this work was study the increase in reading performance in children with Developmental Dyslexia using a prismatic lens. The method utilized was clinical tryal. 300 patients diagnosed with Developmental Dyslexia were examined. 78 were selected to the experimental group and 52 to the control group by the inclusion and exclusion criterias . All patients were tested with 4 nasal base prisms in one of the eyes. The refractional error was corrected when necessary. The results showed benefit with this optical device...

Spinning-disk confocal microscopy -- a cutting-edge tool for imaging of membrane traffic.

Confocal laser scanning microscopy is experiencing a revolution in speed from the world of seconds to that of milliseconds. The spinning Nipkow disk method with microlenses has made this remarkable innovation possible. In combination with the ultrahigh-sensitivity, high-speed and high-resolution camera system based on avalanche multiplication of photoconduction, we are now able to observe the extremely dynamic movement of small vesicles in living cells in real time.