2006 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Nervous System And Sense Organs 320-389 > Inflammatory Diseases Of The Central Nervous System 320-327 > Sleep Disorders 327.* > 2006 ICD-9-CM Diagnosis 327.33 Circadian rhythm sleep disorder, irregular sleep-wake type View the most recent version of ICD-9-CM 327.33 327.33 is a specific code that can be used to specify a diagnosis 327.33 contains 2 index entries View the ICD-9-CM Volume 1 327.* hierarchy  Index entries containing 327.33: Disorder - see also Disease sleep 780.50 circadian rhythm 327.30 irregular sleep-wake type 327.33 Disruption sleep wake cycle (24 hour), unspecified 780.55 circadian rhythm 327.33