[Alban Köhler (1874-1947): Inventor of grid therapy]

Grid (or sieve) therapy ("Gitter-" oder "Siebtherapie"), spatially fractionated kilo- and megavolt X-ray therapy, was invented in 1909 by Alban Köhler, a radiologist in Wiesbaden, Germany. He tested it on several patients before 1913 using approximately 60-70kV Hittorf-Crookes tubes. Köhler pushed the X-ray tube's lead-shielded housing against a stiff grid of 1 mm-square iron wires woven 3.0-3.5mm on center, taped tightly to the skin over a thin chamois. Numerous islets unshielded by iron in the pressure-blanched skin were irradiated with up to about 6 erythema doses (ED). The skin was then thoroughly cleansed, disinfected, and bandaged; delayed punctate necrosis healed in several weeks. Although grid therapy was disparaged or ignored until the 1930s, it has been used successfully since then to shrink bulky malignancies. Also, advanced cancers in rats and mice have been mitigated or ablated using Köhler's concept since the early 1990s by unidirectional or stereotactic exposure to an array of nearly parallel microplanar (25-75μm-wide) beams of very intense, moderately hard (median energy approximately 100 keV) synchrotron-generated X rays spaced 0.1-0.4mm on center. Such beams maintain sharp edges at high doses well beneath the skin yet confer little toxicity. They could palliate some otherwise intractable malignancies, perhaps in young children too, with tolerable sequelae. There are plans for such studies in larger animals.

Problems in functioning from the patient perspective using the International Classification of Functioning, Disability and Health (ICF) as a reference

We conducted a qualitative, multicenter study using a focus group design to explore the lived experiences of persons with any kind of primary sleep disorder with regard to functioning and contextual factors using six open-ended questions related to the International Classification of Functioning, Disability and Health (ICF) components. We classified the results using the ICF as a frame of reference. We identified the meaningful concepts within the transcribed data and then linked them to ICF categories according to established linking rules. The six focus groups with 27 participants yielded a total of 6986 relevant concepts, which were linked to a total of 168 different second-level ICF categories. From the patient perspective, the ICF components: (1) Body Functions; (2) Activities & Participation; and (3) Environmental Factors were equally represented; while (4) Body Structures appeared poignantly less frequently. Out of the total number of concepts, 1843 concepts (26%) were assigned to the ICF component Personal Factors, which is not yet classified but could indicate important aspects of resource management and strategy development of those who have a sleep disorder. Therefore, treatment of patients with sleep disorders must not be limited to anatomical and (patho-)physiological changes, but should also consider a more comprehensive view that includes patient's demands, strategies and resources in daily life and the contextual circumstances surrounding the individual.