A laser scanning device for measuring the distance to an object in a target area by projecting laser light scanningly is provided not only with a light receiving element for receiving reflected light from the target area to detect its intensity but also with an auxiliary light receiving element for receiving reflected light from a neighboring area which will be scanned next. A measurement apparatus for determining the injected drop size or the drop concentration is arranged in or on the intake duct downstream of the location of the injection. The methods and compositions of the invention find use, for example, in treating pulmonary conditions, such as emphysema. In various embodiments, the empty spaces are filled with passive shielding, transmission source assemblies, biopsy instruments, surgical instruments, andor electromagnetic sensors. An interior chamber is in communication with the outlet port and surrounds the filter unit. In combination these traits set \u2018WALSNOFOU\u2019 apart from all other existing varieties of Gaura known to the inventor.