Using novel techniques: INCORRECT. This modifier is dangling, since the sentence contains no noun that is properly modified by using novel techniques. To fix the sentence, we can introduce an agent who actually used the novel techniques (e.g., a doctor), or we can switch to a prepositional phrase, such as through the use o fnovel techniques, that does not contain an -ing verb form.
Developed at the medical school: CORRECT. This past participle modifies techniques.
Correction: The patient’s rare disease was treated through the use ofnovel techniques devel oped at the medical school.
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