Abstract: Perinatal lung maturity is evaluated by determining the fluorescence polarization of a sample of pulmonary effluent containing pulmonary surfactant labeled with a fluorescent dye. The sample is excited with polarized radiation for causing the dye to fluoresce. I.sub.81 and I.sub.195, the intensities of fluorescence polarized in directions parallel to, and perpendicular to, the direction of polarization of the excitation radiation, are measured. From these measurements, the fluorescence polarization P, where P = (I.sub..parallel. - I.sub..perp.)/(I.sub..parallel. + I.sub.195), is determined. The value of P, which is functionally related to the microviscosity of the constituents of the surfactant, has been found to decrease with perinatal lung maturity. When the sample is amniotic fluid containing fetal pulmonary effluent, the evaluation of lung maturity can be carried out antepartum. Postpartum evaluation can be carried out by sampling neonatal tracheal or pharyngeal aspirates.

Abstract: A scintillation camera has a planar scintillating crystal that produces light events whose spatial distribution corresponds to the spatial distribution of the radiation stimuli causing such events, and a plurality of photomultipliers having photocathodes for receiving light from the crystal through a planar face thereof. Computing circuitry coupled to the photomultipliers computes the projection of a light event in the crystal on a reference axis by forming an analytical function of the outputs of the photomultipliers according to the spatial location of the light event in the crystal.

Abstract: A head for a scintillation camera has a planar scintillating crystal that responds to radiation stimuli by producing light events whose spatial distribution corresponds to the spatial distribution of the radiation stimuli, and a plurality of photomultipliers each having a photocathode facing the crystal and producing an output signal when a light event occurs. The photomultipliers are organized into a first group arranged in a cluster centrally positioned relative to the crystal and having smaller photocathodes than those in the second group which is arranged in an annular array surrounding the first group. The head of the camera is connected to signal processing circuitry for computing each of two spatial coordinates of a light event by forming analytical functions of the output signals. Such circuitry has two selective modes of operation.

Abstract: A video-display processor produces an on-line display of the distribution density of radiation stimuli emitted by a radiation field utilizing a probe for detecting the stimuli and a counter for accumulating the number of stimuli detected; and motorized means to cause the probe to traverse the field and sequentially scan a preselected number of elemental areas, each having a preselected size, for causing the probe counter to accumulate the number of stimuli that occurred during the scan of each elemental area. The number of stimuli accumulated during the scan of each elemental area, upon the completion of the scan thereof is transferred into a memory whose contents modulate the picture elements of a raster generated by a CRT of a TV display thus displaying the density of each elemental area immediately after scanning thereof is complete.