Fast 5DOF needle tracking in iOCT

Int J Comput Assist Radiol Surg. 2018 Jun;13(6):787-796. doi: 10.1007/s11548-018-1751-5. Epub 2018 Mar 30.


Purpose: Intraoperative optical coherence tomography (iOCT) is an increasingly available imaging technique for ophthalmic microsurgery that provides high-resolution cross-sectional information of the surgical scene. We propose to build on its desirable qualities and present a method for tracking the orientation and location of a surgical needle. Thereby, we enable the direct analysis of instrument-tissue interaction directly in OCT space without complex multimodal calibration that would be required with traditional instrument tracking methods.

Method: The intersection of the needle with the iOCT scan is detected by a peculiar multistep ellipse fitting that takes advantage of the directionality of the modality. The geometric modeling allows us to use the ellipse parameters and provide them into a latency-aware estimator to infer the 5DOF pose during needle movement.

Results: Experiments on phantom data and ex vivo porcine eyes indicate that the algorithm retains angular precision especially during lateral needle movement and provides a more robust and consistent estimation than baseline methods.

Conclusion: Using solely cross-sectional iOCT information, we are able to successfully and robustly estimate a 5DOF pose of the instrument in less than 5.4 ms on a CPU.

Keywords: Geometric modeling; Instrument tracking; Ophthalmic tool tracking; Optical coherence tomography; iOCT.

MeSH terms

  • Algorithms*
  • Animals
  • Cross-Sectional Studies
  • Disease Models, Animal
  • Equipment Design
  • Eye Diseases / diagnostic imaging
  • Eye Diseases / surgery*
  • Microsurgery / instrumentation*
  • Needles*
  • Ophthalmologic Surgical Procedures / instrumentation*
  • Surgery, Computer-Assisted / methods*
  • Swine
  • Tomography, Optical Coherence / methods*