Yes, Trigeminal Neuralgia is Characteristically Unilateral
Trigeminal neuralgia is almost always a one-sided (unilateral) condition, presenting with paroxysmal attacks of sharp, shooting, electric shock-like pain in the distribution of one or more branches of the trigeminal nerve on one side of the face. 1, 2, 3
Clinical Presentation Confirms Unilateral Nature
- The pain is unilateral, following the distribution of one or more branches of the trigeminal nerve, most commonly affecting the second (maxillary) and third (mandibular) divisions 3, 4
- Attacks last seconds to minutes with a refractory period between episodes, during which the same side cannot be retriggered 1, 2
- Imaging studies consistently demonstrate findings on the symptomatic side only, with trigeminal nerve size measurements reported as smaller on the affected side compared to the contralateral side 5
Diagnostic Imaging Supports Lateralization
- MRI with high-resolution thin-cut sequences shows neurovascular compression at the trigeminal root entry zone on the symptomatic side 3
- Advanced MRI techniques including DTI demonstrate microstructural tissue changes in the symptomatic nerve compared to the asymptomatic contralateral nerve 5
- The congruence between imaging findings and intraoperative findings for neurovascular contact ranges from 83% to 100%, consistently showing unilateral pathology 5
Important Clinical Caveat
If a patient presents with bilateral facial pain, strongly reconsider the diagnosis. Bilateral presentation should prompt evaluation for:
- Secondary causes such as multiple sclerosis, which can cause trigeminal neuralgia but may affect both sides 3, 4
- Alternative diagnoses including trigeminal autonomic cephalgias, which can be mistaken for trigeminal neuralgia 1
- Other structural lesions such as tumors that may affect bilateral trigeminal pathways 4
The guideline literature consistently refers to "isolated unilateral trigeminal neuralgia" as the standard presentation, reinforcing that bilateral symptoms are atypical and warrant expanded differential diagnosis 5.