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T Ohlsson

Publications and source records attributed to T Ohlsson.

3 recordsLinked to original sources

A PET system based on 2-18FDG production with a low energy electrostatic proton accelerator and a dual headed PET scanner.

We have developed a comparatively inexpensive PET system, based on a rotating scanner with two scintillation camera heads, and a nearby low energy electrostatic proton accelerator for production of short-lived radionuclides. Using a 6 MeV proton beam of 5 microA, and by optimization of the target geometry for the 18O(p,n)18F reaction, 750 MBq of 2-18FDG can be obtained. The PET scanner shows a spatial resolution of 6 mm (FWHM) and a sensitivity of 80 s-1kBq-1ml-1 (3 kcps/microCi/ml). Various corrections are included in the imaging process, to compensate for spatial and temporal response variations in the detector system. Both filtered backprojection and iterative reconstruction methods are employed. Clinical studies have been performed with acquisition times of 30-40 min. The system will be used for clinical experimental research with short- as well as long-lived positron emitters. Also the possibility of true 3D reconstruction is under evaluation.

Astrocytoma

Techniques in microlaryngoscopic photography.

A microlaryngoscopic photographic technique is described similar to that technique advocated by Kleinsasser. This technique is an uncomplicated routine method, which can be adopted by anyone using the Zeiss surgical microscope. With a relaxed, intubated patient, alignment of the optical axis of the microscope with the central axis of the laryngoscope, and with careful focusing, using the over-changed (9.5 A, 7.6 V) 6 V 50 W bulb, shutter at 22, magnification of 16 or 25, and with 1/4 second exposure time, and the Kodak Ektachrome HS film (125 ASA), the result should be satisfactory.

Humans