{"id":1084,"date":"2020-12-07T22:10:48","date_gmt":"2020-12-07T14:10:48","guid":{"rendered":"https:\/\/www.yohz.com\/blogs\/?p=1084"},"modified":"2020-12-16T09:58:31","modified_gmt":"2020-12-16T01:58:31","slug":"searching-for-numbers-in-dicom-text-tags","status":"publish","type":"post","link":"https:\/\/www.yohz.com\/blogs\/2020\/12\/07\/searching-for-numbers-in-dicom-text-tags\/","title":{"rendered":"Searching for numbers in DICOM text tags"},"content":{"rendered":"

Some DICOM tags store a numerical value along with some textual information.\u00a0 \u00a0This makes it difficult to search for a specific value using mathematical operators.<\/p>\n

For e.g. the age tag [00101010] in my DICOM images store the patient age together with a prefix (0) and a suffix (Y) i.e.\"\"<\/p>\n

If we want to search for images where the patient age is between 50 and 60, we would need to write our search query like this:<\/p>\n

age IN (‘050Y’, ‘051Y’, ‘052Y’, ‘053Y’, ‘054Y’, ‘055Y’, ‘056Y’, ‘057Y’, ‘058Y’, ‘059Y’, ‘060Y’)<\/p>\n

which is very tedious and error-prone.\u00a0 In DICOM Search<\/a> 1.2, we added the EXTRACTNUMBER<\/strong> and EXTRACTNUMBERDEF<\/strong> functions to deal with this issue.<\/p>\n

EXTRACTNUMBER<\/strong> will extract the first sequence of digits from the tag value and return the number.\u00a0 If there is no valid digits, the value 0 is returned.\u00a0 We can then rewrite our search query this way:<\/p>\n

EXTRACTNUMBER(age) >= 50 AND EXTRACTNUMBER(age) <= 60<\/p>\n

or<\/p>\n

EXTRACTNUMBER(age) > 49 AND EXTRACTNUMBER(age) < 61<\/p>\n

or<\/p>\n

EXTRACTNUMBER(age) IN (50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60)<\/p>\n

The EXTRACTNUMBERDEF<\/strong> function accepts a 2nd parameter as the default value to use when no digits exist in the value.\u00a0 If our search query was written this way:<\/p>\n

EXTRACTNUMBERDEF(age, -1) = -1<\/p>\n

then any images where the age tag value does not contain numbers will return the value -1, and we can then easily see which of our images does not contain a valid age value.<\/p>\n

<\/fb:like><\/div>
<\/div><\/div>","protected":false},"excerpt":{"rendered":"

Some DICOM tags store a numerical value along with some textual information.\u00a0 \u00a0This makes it difficult to search for a specific value using mathematical operators. For e.g. the age tag [00101010] in my DICOM images store the patient age together with a prefix (0) and a suffix (Y) i.e. If we want to search for […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[126],"tags":[129],"_links":{"self":[{"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/posts\/1084"}],"collection":[{"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/comments?post=1084"}],"version-history":[{"count":2,"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/posts\/1084\/revisions"}],"predecessor-version":[{"id":1116,"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/posts\/1084\/revisions\/1116"}],"wp:attachment":[{"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/media?parent=1084"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/categories?post=1084"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yohz.com\/blogs\/wp-json\/wp\/v2\/tags?post=1084"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}