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83661 L/s ratio fetal lung

Pathology & Lab

Also known as: L/S ratio, lecithin/sphingomyelin ratio

Determination of lecithin-to-sphingomyelin (L/S) ratio in amniotic fluid by thin-layer chromatography for assessment of fetal lung maturity.

In Plain Language

lung maturity test; baby's breathing readiness

Clinical Context

Assessment of fetal lung maturity in high-risk obstetric conditions requiring preterm delivery. Ratio greater than 2:1 indicates low risk of respiratory distress syndrome.

RVU Information

CPT 83661 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.

Billing & Documentation

Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.

How This Code Compares

This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.

Specialties

PathologyObstetricsMaternal-Fetal Medicine

Frequently Asked Questions

What is CPT code 83661?

CPT 83661 (L/s ratio fetal lung) is a Pathology & Lab code. Determination of lecithin-to-sphingomyelin (L/S) ratio in amniotic fluid by thin-layer chromatography for assessment of fetal lung maturity.

Who uses CPT code 83661?

CPT 83661 is used by Pathology, Obstetrics, Maternal-Fetal Medicine. Assessment of fetal lung maturity in high-risk obstetric conditions requiring preterm delivery. Ratio greater than 2:1 indicates low risk of respiratory distress syndrome.

When is CPT 83661 used?

Assessment of fetal lung maturity in high-risk obstetric conditions requiring preterm delivery. Ratio greater than 2:1 indicates low risk of respiratory distress syndrome.

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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.