title: Can pontine trigeminal T2-hyperintensity suggest herpetic etiology of trigeminal neuralgia?
abstract: BACKGROUND
  Trigeminal neuralgia (TN) is usually classified into two different categories: idiopathic and secondary. We have investigated the frequency of brainstem pontine lesions in patients with idiopathic TN without multiple sclerosis (MS) or stroke, and their association with herpes zoster (HZ) infection.
  
  
  METHODS
  Brain magnetic resonance imaging (MRI) studies of 28 patients with TN were retrospectively reviewed.
  
  
  RESULTS
  We found seven patients with clinical suspicion of HZ infection and pontine T2 hyperintense lesions, associated with nerve atrophy in one case. Fifteen patients had a neurovascular conflict (NVC) without brainstem involvement, two of them associated with trigeminal atrophy, while four patients had only volumetric reduction of the nerve. In all patients MRI findings were ipsilateral to the side of TN.
  
  
  CONCLUSIONS
  Pontine T2 hyperintensities could be considered as a MRI sign of TN in patients without NVCs. This "trigeminal pontine sign" (TPS) is frequently found in association with herpetic infections.
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: D'Amico
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Carmela
authors.initials: C
authors.lastname: Russo
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Ugga
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Mazio
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Capone
authors.affiliation: Department of Neuroradiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
authors.forename: Felice
authors.initials: F
authors.lastname: D'Arco
authors.affiliation: Department of Neuroradiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
authors.forename: Kshitij
authors.initials: K
authors.lastname: Mankad
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Caranci
authors.affiliation: Department of Neurosciences and Reproductive and Odontostomatological Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Marano
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Arturo
authors.initials: A
authors.lastname: Brunetti
keywords: Trigeminal neuralgia (TN); herpes zoster (HZ); neurovascular conflict; pontine lesion; trigeminal nerve