Author response: RCVS2 score and diagnostic approach for reversible cerebral vasoconstriction syndrome.

Abstract

We thank Drs. Yuan and Hu for their comments. We already acknowledged the sample size limitation, the need for external validation, the need to assess RCVS2 score performance in distinguishing RCVS from arteriopathies other than primary angiitis of the CNS, and that advanced vessel wall imaging or biomarker studies are unlikely to improve on the near-perfect performance of RCVS2 scores >5 or <2 (but may have some utility in patients with intermediate scores 3 or 4).1 With regard to a possible high false-positive rate for thunderclap headache and vasoconstrictive triggers, we believe that this is unlikely. Thunderclap headache is a unique and unforgettable symptom, so documentation is usually accurate. Patients tend to underreport vasoconstrictive triggers such as illicit drugs and over-the-counter medications, so a high false-negative rate is more likely.