@Override
    public List<Study> getStudies() {
        if(studies != null)
            return studies;
        
        File[] imageFiles = directory.listFiles();
        Arrays.sort(imageFiles);
        
        studies = new ArrayList<Study>();
        
        for(File f : imageFiles)
            if(f.isDirectory())
                studies.add(new LocalStudy(f));
        
        return studies;
    }