Volumetric OCT image data processing

A non-transitory, computer-readable storage medium storing computer program instructions which, when executed by a processor, cause the processor to execute a method of processing C-scan data, which comprises a sequence of B-scans of an imaging target, which has been acquired by an optical coherence tomography, OCT, imaging system, to generate correction data for compensating for axial displacements between B-scans in the sequence of B-scans caused by a relative motion of the OCT imaging system and the imaging target that varies a distance therebetween during acquisition of the B-scans by the OCT imaging system, the method comprising generating the correction data by:

• determining, for each pair of adjacent B-scans of a plurality of pairs of adjacent B-scans in the sequence, a respective indicator of an axial shift between respective representations of a common ocular feature in the adjacent B-scans, wherein a variation of the determined indicators with locations of the corresponding pairs of adjacent B-scans in the sequence is defined by a set of frequency components of the variation;
• and
• determining, from the variation of the determined indicators with locations of the corresponding pairs of adjacent B-scans in the sequence, a first frequency component of the set of frequency components, the first frequency component being indicative of the relative motion of the OCT imaging system and the imaging target during acquisition of the B-scans by the OCT imaging system.

A data processing apparatus configured to process C-scan data, which comprises a sequence of B-scans of an imaging target, which has been acquired by an optical coherence tomography, OCT, imaging system, to generate correction data for compensating for axial displacements between B-scans in the sequence of B-scans caused by a relative motion of the OCT imaging system and the imaging target that varies a distance therebetween during acquisition of the B-scans by the OCT imaging system, the data processing apparatus comprising:

• an axial shift determination module arranged to determine, for each pair of adjacent B-scans of a plurality of pairs of adjacent B-scans in the sequence, a respective indicator of an axial shift between respective representations of a common ocular feature in the adjacent B-scans, wherein a variation of the determined indicators with locations of the corresponding pairs of adjacent B-scans in the sequence is defined by a set of frequency components of the variation;
• and
• a frequency component determination module arranged to determine, from the variation of the determined indicators with locations of the corresponding pairs of adjacent B-scans in the sequence, a first frequency component of the set of frequency components, the first frequency component being indicative of the relative motion of the OCT imaging system and the imaging target during acquisition of the B-scans by the OCT imaging system.

A data processing apparatus configured to process C-scan data, which comprises a sequence of B-scans of an imaging target, which has been acquired by an optical coherence tomography, OCT, imaging system, to generate correction data for compensating for axial displacements between B-scans in the sequence of B-scans caused by a relative motion of the OCT imaging system and the imaging target that varies a distance therebetween during acquisition of the B-scans by the OCT imaging system, the data processing apparatus comprising:

• a storage device storing a computer program comprising instructions;
• and
• a computer processor arranged to execute the instructions to:
• determine, for each pair of adjacent B-scans of a plurality of pairs of adjacent B-scans in the sequence, a respective indicator of an axial shift between respective representations of a common ocular feature in the adjacent B-scans, wherein a variation of the determined indicators with locations of the corresponding pairs of adjacent B-scans in the sequence is defined by a set of frequency components of the variation, and
• determine, from the variation of the determined indicators with locations of the corresponding pairs of adjacent B-scans in the sequence, a first frequency component of the set of frequency components, the first frequency component being indicative of the relative motion of the OCT imaging system and the imaging target during acquisition of the B-scans by the OCT imaging system.