A method, comprising: obtaining, by a processor, an ultrasound image generated based on one or more ultrasound signals from an imaged region of a subject; determining, by the processor, a shadow profile based on the ultrasound image by performing shadow detection on harmonic frequency ultrasound data in the ultrasound image, comprising calculating shadow intensity data based on the harmonic frequency ultrasound data, wherein the shadow profile represents the location of a boundary between a shadow region and tissue in the ultrasound image; convoluting the shadow profile with a matched filter that approximates an expected shadow profile of a target anatomy resulting in a filtered shadow profile; identifying, by the processor and based on the filtered shadow profile, anatomical landmarks present in the imaged region, by detecting peaks or one or more other features on the filtered shadow profile, selecting a subset of most prominent peaks or a subset of the one or more other features and classifying the peaks or other subset as anatomical landmarks; extracting features of the anatomical landmarks by measuring depth of the anatomical landmarks corresponding to the peaks, measuring lateral position of the anatomical landmarks corresponding to the peaks and measuring angle of a spine midline; generating, by the processor and based on the filtered shadow profile, a classification of the anatomical landmark by calculating a confidence/classification metric by measuring or otherwise determining a height and/or other characteristics of the anatomical landmark and determining a metric that is indicative of a confidence level that the anatomical landmark is in the ultrasound image based on the determined height and/or other characteristics, classifying anatomy as containing the target anatomy or not and determining the accuracy of the extracted features of the anatomical landmarks based on confidence metric; and displaying, on a display of a handheld ultrasound imager, a composite image based on the ultrasound image and based on the classification of the anatomical landmark. obtaining, by a processor, an ultrasound image generated based on one or more ultrasound signals from an imaged region of a subject; determining, by the processor, a shadow profile based on the ultrasound image by performing shadow detection on harmonic frequency ultrasound data in the ultrasound image, comprising calculating shadow intensity data based on the harmonic frequency ultrasound data, wherein the shadow profile represents the location of a boundary between a shadow region and tissue in the ultrasound image; convoluting the shadow profile with a matched filter that approximates an expected shadow profile of a target anatomy resulting in a filtered shadow profile; identifying, by the processor and based on the filtered shadow profile, anatomical landmarks present in the imaged region, by detecting peaks or one or more other features on the filtered shadow profile, selecting a subset of most prominent peaks or a subset of the one or more other features and classifying the peaks or other subset as anatomical landmarks; extracting features of the anatomical landmarks by measuring depth of the anatomical landmarks corresponding to the peaks, measuring lateral position of the anatomical landmarks corresponding to the peaks and measuring angle of a spine midline; generating, by the processor and based on the filtered shadow profile, a classification of the anatomical landmark by calculating a confidence/classification metric by measuring or otherwise determining a height and/or other characteristics of the anatomical landmark and determining a metric that is indicative of a confidence level that the anatomical landmark is in the ultrasound image based on the determined height and/or other characteristics, classifying anatomy as containing the target anatomy or not and determining the accuracy of the extracted features of the anatomical landmarks based on confidence metric; and displaying, on a display of a handheld ultrasound imager, a composite image based on the ultrasound image and based on the classification of the anatomical landmark.