Chronic central neuropathic pain

Definition

Chronic central neuropathic pain is chronic pain caused by a lesion or disease of the central somatosensory nervous system [1]. Somatosensory pathways may be affected at any anatomical level from the dorsal horn of the spinal cord to the cerebral cortex. Common causes of chronic central neuropathic pain include ischemic or hemorrhagic stroke, trauma, and multiple sclerosis [2-4]. Multiple sclerosis and similar diseases with a disseminated pathology may involve somatosensory pathways at multiple levels in both spinal cord and brain. Persistence or recurrence over ≥ 3 months defines chronic pain (see 6 Temporal Properties). The pain may be spontaneous or evoked, as an increased response to a painful stimulus (hyperalgesia) or a painful response to a normally nonpainful stimulus (allodynia). The diagnosis of central neuropathic pain requires a history of central nervous system injury or disease and a neuroanatomically plausible distribution of the pain [5]. Negative (e.g., decreased or loss of sensation) and positive sensory symptoms or signs (e.g., allodynia or hyperalgesia) must be compatible with the central nervous system lesion or disease. Demonstration of the lesion or disease involving the central nervous system, e.g., by imaging techniques, confirms the diagnosis of definite central neuropathic pain [5]. For additional information see Chronic neuropathic pain Diagnostic Criteria: For the diagnosis of chronic central neuropathic pain, pain must persist or recur for ≥ 3 months and fulfill at least criteria A and D below. Criteria B and C increase the level of diagnostic certainty. A. The pain is characterized by both of the following: A.1 History of relevant neurological lesion or disease affecting the central somatosensory system A.2 Pain distribution neuroanatomically plausible B. Pain is associated with sensory signs in the same neuroanatomically plausible distribution C. Diagnostic test confirming a lesion or disease of the central somatosensory nervous system explaining the pain D. Not better accounted for by another diagnosis of chronic pain. Comments Negative or positive sensory signs consistent with the distribution of the pain may be sufficient to indicate the presence of a lesion or disease of the peripheral somatosensory nervous system. The clinical examination may be supplemented by laboratory tests, e.g., quantitative sensory testing. Tests that reveal the relevant lesion or disease affecting the somatosensory system may, e.g., consist of surgical or radiological confirmation of nerve compression, nerve conduction study, laser-evoked potentials, blink reflex, or skin biopsy confirmation of reduced nerve fibre terminals. Positive findings in these investigations may provide important diagnostic hints at the source of pain. However, all clinical and diagnostic aspects of the pain need to be considered before assuming causality. If clinical examination or diagnostic testing are performed, and the results are negative, neuropathic pain is unlikely (or less likely). Consider using another chronic pain diagnosis.

Inclusions

• Chronic central neuropathic pain associated with spinal cord injury
• Chronic central neuropathic pain associated with brain injury
• Chronic central post stroke pain
• Chronic central neuropathic pain associated with multiple sclerosis

Index Terms