The physics of image formation in the neuroendoscope

Introduction: The development of the neuroendoscope has allowed neurosurgeons to visualize anatomic structures deep within the nervous system with minimal disruption of the critical overlying structures. This has enabled the development of an entire system of tools and techniques for maximum effective action at the target point through minimal corridors for the treatment of an entire spectrum of pathologies. Discussion: The design of an optical instrument with the a bility to illuminate deep, hidden anatomic structures and transmit those images accurately and brightly to the eye of the neurosurgeon poses several challenges. These challenges have been met by advances in lens design and optical systems engineering over a period of several decades leading up to emergence of the modern neuroendoscope. In this paper, the basic concepts of the physics of image formation in optical systems are reviewed with emphasis on those elements critical to the endoscope. Conclusion: A consideration of these basic concepts is critical to the understanding of the limitations and capabilities of the key instrument for neuroendoscopy.