Method and apparatus for correlated ophthalmic measurements

Abstract

A method and system providing multiple ophthalmic and retinal blood measurements is outlined. By extracting multiple digitized wavelength images and quantitative data within a relatively short time period the method allows for compensation of a patients eye or head movement, generation of ophthalmic clinical records, and determination of data relating to blood measurements, such as oxygen saturation and hemoglobin, in addition to ocular and other disease determinations. The method provides for multiple analysis and measurements within a single sitting of the patient, with a single simple instrument and without adaptations to the instrument during a patients eye examination. Beneficially the approach allows for low cost, compact, and even portable implementations offering such analysis and determination outside the current ophthalmic centers providing eased access and earlier diagnosis opportunities.

1 . A system comprising;
 an optical source, the optical source comprising at least a control port, the optical source for providing a source optical signal at least one of a plurality of predetermined wavelengths, the one of the plurality of predetermined wavelengths being established in dependence of a control wavelength signal provided to the control port;   a detector, the detector comprising at least an output port, the detector for receiving a detected optical signal, generating at least a digital representation of a detected optical signal, and providing the digital representation of a detected optical signal at the output port as a detected electrical signal;   an optical coupling, the optical coupling for coupling the source optical signal to a patients eyeball, receiving at least a signal returned from the eyeball of the patient, and providing the reflected optical signal to the detector, the reflected optical signal therefore forming at least a portion of the detected optical signal; and,   a controller, the controller being electrically connected to at least the control port and output port, the controller for providing at least one of a plurality of control wavelength signals, receiving the detected electrical signal, and providing a processed electrical signal, the processed electrical signal being determined at least in dependence upon the detected electrical signal, the control wavelength signal, and a predetermined factor.   
     
     
         2 . A system according to  claim 1  wherein,
 the controller provides at least two processed electrical signals during a single sitting of the patient, the two processed electrical signals being provided in response to the controller providing two different control wavelength signals of the plurality of control wavelength signals. 
 
     
     
         3 . A system according to  claim 1  wherein,
 the controller provides a plurality of processed electrical signals, each of the plurality of processed signals being at least one of dependent upon a different characteristic of the patients eyeball and obtained without a reconfiguration of the system other than providing at least a subset of the plurality of optical wavelengths. 
 
     
     
         4 . A system according to  claim 3  wherein,
 receiving a signal returned from the eyeball comprises receiving an optical signal that is generated by at least one of scatter signal, specular reflection, fluorescence, raman scattering, speckle signal, and absorption in response to the provided a source optical signal. 
 
     
     
         5 . A system according to  claim 1  wherein,
 the optical source comprises at least one of a tunable laser, an incandescent bulb, a tunable optical filter, at least one of plurality of predetermined optical filters, a spectrometer, and a multiple solid state light emitting diode. 
 
     
     
         6 . A system according to  claim 1  wherein,
 the detector comprises at least one of a photodetector and analog-to-digital converter, an array of photodiodes and at least an analog-to-digital converter, and a charge coupled device. 
 
     
     
         7 . A system according to  claim 1  wherein,
 the optical coupling comprises at least one of a lens, a mirror a beam-splitter, a wavelength filter, a rest and a restraint. 
 
     
     
         8 . A system according to  claim 7  wherein,
 at least one of the rest and restraint provide a predetermined optical configuration of at least the optical source detector, and patients eyeball. 
 
     
     
         9 . A system according to  claim 1  wherein,
 the optical coupling provides a predetermined optical configuration of at least the optical source, detector, and patients eyeball. 
 
     
     
         10 . A system according to  claim 1  further comprising;
 a memory, the memory for storing at least the processed electrical signal. 
 
     
     
         11 . A system according to  claim 10  wherein,
 the memory comprises a computer memory, a computer disk drive, a computer readable storage medium, a memory drive, a memory chip, a smart card, and a networked computer disk drive. 
 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . A method comprising;
 providing an ophthalmic instrument, the ophthalmic instrument comprising at least a multi-wavelength optical source, an optical wavelength filter, and a detector, the ophthalmic instrument for providing a digital output determined in dependence upon at least a state of the machine and the wavelength of the multi-wavelength optical source;   providing a rest, the rest for providing a predetermined relationship between a patients head engaged with at least the rest and the ophthalmic instrument; and,   determining with a single placement of the patients head with respect to the ophthalmic instrument at least one measurement of a plurality of measurements of the patient, each of the plurality of measurements determined in dependence upon at least the digital output.   
     
     
         17 . A method according to  claim 16  further comprising;
 determining at least a second measurement of the plurality of measurements of the patient, the second measurement being taken during the same sitting of the patient. 
 
     
     
         18 . A method according to  claim 16  wherein,
 determining with a single placement comprises providing no reconfiguration of the ophthalmic instrument other than a change in the at least one of the multi-wavelength optical source and the optical wavelength filter. 
 
     
     
         19 . A method according to  claim 18  wherein,
 providing no reconfiguration is other than providing an optical signal to the patients head at one optical wavelength of a plurality of optical wavelengths other than the current optical wavelength of the plurality of optical wavelengths. 
 
     
     
         20 . A method according to  claim 16  further comprising;
 determining at least a characteristic of a plurality of characteristics of the patient, in dependence upon at least one of a predetermined portion of the plurality of measurements of the patient and a state of the ophthalmic instrument, the predetermined portion of the plurality of measurements at least one of employed as is, employed with a crop applied to reduce a dimension of each measurement, and employed with an offset applied to align all measurements of the plurality of measurements to a common feature. 
 
     
     
         21 . A method according to  claim 20  wherein,
 the plurality of measurements generated in dependence upon an optical signal from the multi-wavelength optical source relate to at least one of providing the optical signal with a predetermined wavelength sequence of a plurality of wavelengths, at a first predetermined wavelength and multiple predetermined time intervals, and at a second predetermined wavelength act as a probe followed by multiple measurements at least one of predetermined time intervals and predetermined wavelengths after the probe signal has been applied. 
 
     
     
         22 . A method according to  claim 20  wherein,
 determining a characteristic of the patient further comprises at least one of applying a predetermined process to the plurality of measurements of the patient, employing at least one measurement of the patient from a previous testing of the patient and weighting the determination in respect of a characteristic of the patient. 
 
     
     
         23 . A method according to  claim 20  wherein,
 determining a characteristic of the patient at least in dependence upon the state of the ophthalmic instrument comprises determining the characteristic in dependence upon at least one of a mathematical algorithm and a computer process, the at least one of mathematical algorithm and computer process being different for each state of the ophthalmic instrument. 
 
     
     
         24 . A method according to  claim 16  farther comprising;
 storing the at least one characteristic of a plurality of characteristics of the patient. 
 
     
     
         25 . A method according to  claim 21  wherein,
 storing the at least one characteristic comprises storing at least one of the output of the detector for a predetermined subset of the plurality of wavelengths and the result of a process applied to the output of the detector. 
 
     
     
         26 . A method according to  claim 24  wherein,
 storing the characteristic comprises storing the characteristic in at least one of a computer memory, a computer disk drive, a computer readable storage medium, a memory drive, a memory chip, a smart card, and a networked computer disk drive. 
 
     
     
         27 . A method according to  claim 24  further comprising;
 providing the at least one characteristic of a plurality of characteristics of the patient to at least an operator of the ophthalmic instrument. 
 
     
     
         28 . A method according to  claim 24  wherein,
 providing to at least an operator comprises providing at least one of a visual representation, a text representation, a numerical representation, and a graphical representation of the characteristic to the operator. 
 
     
     
         29 . A method according to  claim 24  wherein,
 providing the at least one representation further comprises providing at least an indication of an anomaly within the at least one of the characteristic and the plurality of characteristics.