title: Comparison of the radioisotope cisternography findings of spontaneous intracranial hypotension and iatrogenic cerebrospinal fluid leakage focusing on chronological changes.
abstract: BACKGROUND
  Radioisotope cisternography (RICG) is useful for detecting cerebrospinal fluid (CSF) leakage in spontaneous intracranial hypotension (SIH) patients. However, RICG can cause iatrogenic CSF leakage (ICSFL) due to a lumbar puncture.
  
  
  OBJECTIVE
  To compare the RICG findings of SIH and ICSFL.
  
  
  METHODS
  The presence of direct findings suggesting CSF leakage and indirect findings including early visualization of the bladder and absence of radioactivity over the brain convexities were evaluated in seven SIH and six ICSFL patients. Radioisotope clearance was assessed semi-quantitatively.
  
  
  RESULTS
  In contrast to the variety of anatomical levels at which direct findings were detected in the SIH patients, the ICSFL patients only displayed direct findings at the lumbosacral level. None of the ICSFL patients displayed direct findings at 1 hour after the tracer injection. Although early visualization of the bladder was depicted in all patients, no activity was visualized over the brain convexities in the SIH patients. In the semi-quantitative analysis, the tracer retention index at 24 hours was lower in the SIH patients than the ICSFL patients.
  
  
  CONCLUSIONS
  The early appearance of direct findings above the lumbosacral level, the absence of radioactivity over the brain convexities and a low tracer retention index are suggestive of SIH.
authors.affiliation: Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Japan. ksak666@yahoo.co.jp
authors.forename: Keita
authors.initials: K
authors.lastname: Sakurai
authors.forename: Minoru
authors.initials: M
authors.lastname: Nishio
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yamada
authors.forename: Masashi
authors.initials: M
authors.lastname: Shimohira
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ozawa
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Matsukawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Oguri
authors.forename: Yoshino
authors.initials: Y
authors.lastname: Ueki
authors.forename: Junko
authors.initials: J
authors.lastname: Tohyama
authors.forename: Takemori
authors.initials: T
authors.lastname: Yamawaki
authors.forename: Yuta
authors.initials: Y
authors.lastname: Shibamoto
mesh_terms: D000328:Adult; D065634:Cerebrospinal Fluid Leak; D002559:Cerebrospinal Fluid Rhinorrhea / Q000000981:diagnostic imaging* / Q000209:etiology*; D003937:Diagnosis, Differential; D042241:Early Diagnosis; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D019586:Intracranial Hypertension / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009192:Myelography / Q000379:methods*; D011877:Radionuclide Imaging; D013129:Spinal Puncture / Q000009:adverse effects*