Trigeminal neuralgia: New classification and diagnostic grading for practice and research.
Trigeminal neuralgia (TN) is an exemplary condition of neuropathic facial pain. However, formally classifying TN as neuropathic pain based on the grading system of the International Association for the Study of Pain is complicated by the requirement of objective signs confirming an underlying lesion or disease of the somatosensory system. The latest version of the International Classification of Headache Disorders created similar difficulties by abandoning the term symptomatic TN for manifestations caused by major neurologic disease, such as tumors or multiple sclerosis. These diagnostic challenges hinder the triage of TN patients for therapy and clinical trials, and hamper the design of treatment guidelines. In response to these shortcomings, we have developed a classification of TN that aligns with the nosology of other neurologic disorders and neuropathic pain. We propose 3 diagnostic categories. Classical TN requires demonstration of morphologic changes in the trigeminal nerve root from vascular compression. Secondary TN is due to an identifiable underlying neurologic disease. TN of unknown etiology is labeled idiopathic. Diagnostic certainty is graded possible when pain paroxysms occur in the distribution of the trigeminal nerve branches. Triggered paroxysms permit the designation of clinically established TN and probable neuropathic pain. Imaging and neurophysiologic tests that establish the etiology of classical or secondary TN determine definite neuropathic pain.
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Giorgio
G
Cruccu
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Nanna B
NB
Finnerup
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Troels S
TS
Jensen
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Joachim
J
Scholz
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Marc
M
Sindou
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Peter
P
Svensson
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK. rolf-detlef.treede@medma.uni-heidelberg.de.
Rolf-Detlef
RD
Treede
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Joanna M
JM
Zakrzewska
From the Special Interest Group on Neuropathic Pain (NeuPSIG) of the International Association for the Study of Pain (G.C., N.B.F., T.S.J., J.S., R.-D.T., T.N.), Washington, DC; Scientific Panel Pain of the European Academy of Neurology (G.C., T.S.J., T.N.), Vienna, Austria; Department of Neurology and Psychiatry (G.C.), Sapienza University, Rome, Italy; Danish Pain Research Centre, Department of Clinical Medicine (N.B.F., T.S.J.), and Section of Orofacial Pain and Jaw Function, Department of Dentistry (P.S.), Aarhus University, Denmark; Departments of Anesthesiology and Pharmacology (J.S.), Columbia University Medical Center, New York, NY; Department of Neurosurgery (M.S.), Hôpital Neurologique "Pierre Wertheimer," University of Lyon 1, Lyon, France; Center for Biomedicine and Medical Technology Mannheim (CBTM) (R.-D.T.), Heidelberg University, Mannheim, Germany; Facial Pain Unit, University College London Hospitals NHS Foundation Trust (J.M.Z.); and Pain Relief (T.N.), Neuroscience Research Centre, The Walton Centre NHS Foundation Trust, Liverpool, UK.
Turo
T
Nurmikko
D006801:Humans; D014277:Trigeminal Neuralgia / Q000145:classification* / Q000175:diagnosis*