The Avesta as a foundation of neurosurgical deontology: From the rules of the Vendidad to contemporary ethical principles

Background: Medical deontology is often presented as a modern construct shaped by the Hippocratic Oath, the Nuremberg Code, and the Declaration of Helsinki. However, earlier normative systems also articulated sophisticated ethical expectations for healers. Among these, the Vendidad, a juridicoritual text of the Avesta, contains prescriptions concerning medical competence, responsibility, universality of care, and equitable remuneration. Reexamining these ancient rules through the lens of contemporary neurosurgical ethics offers an expanded historical perspective on professional deontology. Methods: Relevant passages of the Vendidad were identified and examined for normative content, then compared with contemporary neurosurgical standards, including informed consent, competence validation, and accountability frameworks. Results: The Vendidad articulates four protodeontological principles that parallel modern neurosurgical ethics: Certification of competence through demonstrated successful outcomes. Accountability for surgical failure when competence is not established. Universality of care, mandating treatment irrespective of religious affiliation. Equity in remuneration, proportionate to skill and patient status. These elements reveal a structured ethical framework predating modern codifications. Conclusion: The Vendidad provides an early articulation of principles central to contemporary neurosurgical deontology. Integrating this ancient Iranian perspective enriches the longue durée history of medical ethics and reinforces the philosophical foundations of ethical practice in twentyfirstcentury neurosurgery.