Correct spelling, explanation: scanned is the past tense and past participle of the verb scan in standard English grammar. Scaned is a misspelling and not a recognized word in English. This form doesn’t exist because English spelling rules require doubling the final consonant (in this case, -n) when a single-syllable verb ends with a consonant preceded by a single vowel, as in scan. This rule applies to other similar words: plan → planned, ban → banned, etc. Scanned is the only correct form.

Definition of scanned:
Verb (past tense, past participle), look at all parts of (something) carefully in order to detect some feature
She scanned the crowded room, searching for a familiar face.
The detective scanned the crime scene, looking for any overlooked clues.

Collocations with scanned:
Some of the most commonly used collocations include:
1. Scanned the horizon: to look carefully at the distant landscape for something or someone.
The sailor scanned the horizon for signs of approaching ships.
2. Scanned a document: to examine a paper or electronic file carefully or use a scanning device to digitize it.
He scanned the document to verify the details before signing it.
3. Scanned the room: to look around a room to observe people or objects.
She quickly scanned the room to find an empty seat.
4. Scanned for errors: to review content carefully to identify mistakes.
The editor scanned the article for errors before publishing it.

Incorrect spelling, explanation: the reason you can’t spell scaned instead of scanned comes down to English spelling rules for doubling consonants when adding -ed or -ing to certain verbs. The verb scan follows the consonant-vowel-consonant (CVC) rule: if a verb has a single syllable, ends with a single consonant preceded by a single vowel (like s-c-a-n), and you add a suffix starting with a vowel (like -ed or -ing), you double the final consonant to preserve the short vowel sound.