title: Viewpoint: the type A- and the type B-variants of Decompression Sickness.
abstract: BACKGROUND
  Symptoms of neurological decompression incidents (DCS/AGE) can be severe or mild. It is unknown if these differences of symptom presentation represent different clinical entities or if they represent just the spectrum of DCS/AGE.
  
  
  METHODS
  267 cases with DCS/AGE were compared retrospectively and classified into two subgroups, the Type A-DCS/AGE for cases with a severe and often stroke-like symptomatology and the Type B-DCS/AGE for those with milder and sometimes even doubtful neurological symptoms. The main outcome measures were the number of hyperbaric treatments (HTs) needed and the clinical outcome.
  
  
  RESULTS
  42 patients with DCS/AGE were classified as Type A- and 225 patients met the criteria for a Type B-DCS/AGE. Patients with Type A-lesions were more severely affected, needed more hyperbaric treatments and had a less favorable outcome than patients with the Type B-variant.
  
  
  CONCLUSIONS
  The Type A- and the Type B-DCS/AGE are likely to be different entities with better clinical outcome in the Type B-variant and possibly significant differences in the underlying pathophysiologies of both variants. Future studies with a particular focus on the up to now inadequately investigated Type B-DCS/AGE are necessary to elucidate such differences in the pathophysiology.
authors.affiliation: German Naval Medical Institute, Kiel-Kronshagen, Germany.
authors.forename: A E
authors.initials: AE
authors.lastname: Koch
authors.forename: H
authors.initials: H
authors.lastname: Wegner-Bröse
authors.forename: V
authors.initials: V
authors.lastname: Warninghoff
authors.forename: G
authors.initials: G
authors.lastname: Deuschl
mesh_terms: D000328:Adult; D003665:Decompression Sickness / Q000145:classification* / Q000175:diagnosis / Q000628:therapy; D003937:Diagnosis, Differential; D004242:Diving / Q000009:adverse effects*; D004618:Embolism, Air / Q000145:classification* / Q000175:diagnosis / Q000628:therapy; D005260:Female; D006610:High Pressure Neurological Syndrome / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000706:statistics & numerical data; D008297:Male; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D016896:Treatment Outcome