title: Patient organ radiation doses during treatment for aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  The aim of this retrospective study was to estimate risk organ doses and to estimate radiation risks during the imaging work-up and treatment for aneurysmal subarachnoid hemorrhage (SAH).
  
  
  METHODS
  The imaging procedures comprised computed tomography and digital subtraction angiography studies for diagnosis or endovascular interventional procedures in 50 consecutive patients. Equivalent organ doses (H(T)) to skin, brain, eye lens, salivary glands, thyroid and oral mucosa were measured using thermoluminescence dosimeters in an anthropomorphic head phantom. Picture archiving and communication system (PACS) and radiological information system (RIS) records were analyzed and the frequency of each imaging procedure was recorded as well as the registered individual kerma-length product (P(KL)) and the kerma-area product (P(KA)). The doses were computed by multiplying the recorded P(KL) and P(KA) values by the conversion coefficients H(T)/P(KL) and H(T)/P(KA) from the head phantom.
  
  
  RESULTS
  The mean fluoroscopy time, P(KL) and P(KA) were 38 min, 7269 mGy cm and 286 Gy cm(2), respectively. The estimated mean equivalent doses were as follows: skin 2.51 Sv, brain 0.92 Sv, eye lens 0.43 Sv and salivary glands 0.23 Sv. Maximum organ doses were 2.3-3.5 times higher than the mean. Interventional procedures contributed 66 % to skin dose, 55 % to brain dose and 25 % to eye lens dose. Of the patients with an estimated skin dose exceeding 6 Sv, only 1 developed temporary epilation.
  
  
  CONCLUSIONS
  The risk for radiation-induced cancer for SAH patients is low (2-3 cases per 1,000 patients, of which 90 % are expected to be benign types) compared with the risk of tissue reactions on the head such as skin erythema and epilation (1 temporary epilation per 50 patients).
authors.affiliation: Department for Medical and Health Sciences, Medical Physics, Centre for Medical Image Science and Visualization, Linköping University, County Council of Östergötland, Sweden. michael.sandborg@lio.se
authors.forename: M
authors.initials: M
authors.lastname: Sandborg
authors.forename: J
authors.initials: J
authors.lastname: Nilsson Althén
authors.forename: H
authors.initials: H
authors.lastname: Pettersson
authors.forename: S
authors.initials: S
authors.lastname: Rossitti
mesh_terms: D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging* / Q000628:therapy*; D015901:Angiography, Digital Subtraction / Q000295:instrumentation*; D001921:Brain / Q000528:radiation effects; D002533:Cerebral Angiography / Q000295:instrumentation*; D004621:Embolization, Therapeutic; D004867:Equipment Design; D005260:Female; D006257:Head / Q000528:radiation effects*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation*; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000628:therapy*; D007908:Lens, Crystalline / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000528:radiation effects; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D012867:Skin / Q000528:radiation effects; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000628:therapy*; D013819:Thermoluminescent Dosimetry; D013961:Thyroid Gland / Q000528:radiation effects; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*; D055815:Young Adult