title: Regional cerebral metabolic rate of glucose evaluation and clinical assessment in patients with idiopathic normal-pressure hydrocephalus before and after ventricular shunt placement: a prospective analysis.
abstract: OBJECTIVE
  We prospectively evaluated the regional cerebral metabolic rate of glucose (CMRglu) before and after ventricular shunt placement in idiopathic normal-pressure hydrocephalus (iNPH) patients, to investigate whether some brain regions are more involved than others; we also correlated the individual variations of CMRglu with the clinical scale score assessment after shunting.
  
  
  METHODS
  Twenty iNPH patients (12 men; mean age 73 ± 9 years) underwent clinical scale score assessment and F-FDG PET-CT before and 1 week after shunting.
  
  
  RESULTS
  Before shunting, CMRglu values were similar in right and left brain regions, as well as after shunting. After shunting, 17 of 20 iNPH patients were clinically improved; all scale scores decreased, and CMRglu significantly increased in all regions (P < 10). In 3 of 20 iNPH patients, the symptoms persisted, the scale scores did not change, and CMRglu increased only in 3 regions: left frontal, left putamen, and right thalamus. Before shunting, no difference in global CMRglu between clinically improved (n = 17) and not improved (n = 3) iNPH patients was found. After shunting, a significant (P = 0.01) correlation between individual variations of CMRglu and clinical assessment was found.
  
  
  CONCLUSIONS
  These findings confirm that iNPH is a disease involving all cerebral regions almost in the same way, and shunt procedure has a similar effect on regional cerebral metabolism almost in the same way. Individual variations of CMRglu are more important than absolute values and correlate with clinical status after shunting. Clinical improvement depends not only on the capability to restore the cerebrospinal fluid dynamic, but also on the ability of cerebral parenchyma to recover the metabolic function.
authors: Institutes of Nuclear Medicine, Università Cattolica del Sacro Cuore, Rome, Italy. ml.calcagni@rm.unicatt.it
authors: Maria Lucia
authors: ML
authors: Calcagni
authors: Silvia
authors: S
authors: Taralli
authors: Annunziato
authors: A
authors: Mangiola
authors: Luca
authors: L
authors: Indovina
authors: Mariadea
authors: M
authors: Lavalle
authors: Pasquale
authors: P
authors: De Bonis
authors: Carmelo
authors: C
authors: Anile
authors: Alessandro
authors: A
authors: Giordano
mesh_terms: D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D002557:Cerebrospinal Fluid Shunts; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000601:surgery*; D008297:Male; D049268:Positron-Emission Tomography; D011446:Prospective Studies
chemical_list: D019788:Fluorodeoxyglucose F18; D005947:Glucose