The invention provides for a medical instrument for examining the cervix comprising an optical examination system, a processor for controlling the medical instrument, and a memory containing machine executable instructions. Execution of the instructions causes the processor to: acquire a cervical image using the optical examination system; calculate a set of interest point locations using a digital filter; calculate a filtered set of interest point locations using the set of interest point locations and a morphological filter; calculate a reduced set of interest points locations using the filtered set of interest point locations and a neighborhood based filter; calculate a classified set of interest point locations reduced set of interest points and a trained classification module; calculate a set of punctation locations using the classified set of interest point locations and a second neighborhood based filter; and calculate punctation mark regions using the punctation point locations.