2007 ICD-9-CM Procedure 90.0 Microscopic examination of specimen from nervous system and of spinal fluid 90.0 is a non-specific code that should not be used to specify a procedure 90.0 contains 5 index entries View the full Volume 3 90.* hierarchy Index entries containing 90.0: Examination (for) microscopic (specimen) (of) 91.9 brain 90.0 meninges 90.0 nerve 90.0 nervous system 90.0 spinal fluid 90.0