Patent · US Expired

Method and apparatus for excision endpoint control

US5196006A · kind A · utility

81Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 10, 1991
Grant dateMar 23, 1993
Priority date
Expiry dateOct 10, 2011

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61F2009/00872
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

Methods and apparatus for determining the depth of excision generated by a material removal process, for determining the thickness of unablated material below the excision or incision, and for providing endpoint control of a material removal process utilize acoustic transducers for measuring the time delay between a first acoustic pulse resulting from material removal and a second acoustic pulse reflected from a distal surface or boundary layer of the material. The time delay between the two pulses detected by the transducer provides a measure of excision depth and of the depth of material below the excision. Endpoint control is provided by terminating material removal when a selected excision depth is detected. The invention can be used, for example, as a real-time monitor of excision depth and residual lamella thickness under the excision during laser corneal surgery.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.