Key Takeaways Chemotherapy administration must be sequenced before therapeutic infusions and hydration on every multi-service claim. Start and stop times are required for time-based infusion codes — missing documentation forfeits add-on code reimbursement. The JW and JZ modifiers are mandatory on Medicare claims for single-dose vial drugs; missing either causes claims to be returned unprocessable. […]
Carola Cornejo
Assistant Vice President of Client Services and Operations
Carola Cornejo is Assistant Vice President of Client Services and Operations at PGM Billing, where she has spent more than 15 years specializing in physician billing and revenue cycle management. She is one of PGM’s leading experts in appeals filing and denial resolution, with hands-on experience across patient and insurance collections, claims follow-up, fee schedule analysis, and provider credentialing.
Carola’s work spans PGM’s core physician specialties — including cardiology, orthopedics, neurology, gastroenterology, behavioral health, nephrology, and oncology — making her a trusted resource for practices navigating complex billing and coding challenges. She holds a degree in Computerized Accounting from Dover Business College.
Posts by Carola Cornejo
Orthopedic Billing Denials: Why Claims Fail by Procedure Type
Key Takeaways Joint replacement denials are most often documentation failures, not coding errors — prior authorization and conservative treatment records have to be in the chart before the claim goes out. Fracture care claims fail at the ICD-10 level more than any other orthopedic category; episode-of-care suffix errors and missing laterality are consistent, avoidable denial […]
Medicare Billing for Chiropractors: Coverage Rules, Exclusions, and the Mistakes That Lead to Denials
Key Takeaways Medicare covers exactly one chiropractic service: manual spinal manipulation to correct a subluxation. Every other service a chiropractor commonly provides — x-rays, E/M visits, massage, e-stim, ultrasound, extraspinal manipulation — is statutorily excluded. The AT modifier is required on every Medicare claim for spinal manipulation. Without it, the MAC denies the claim automatically, […]
Why Nephrology Billing Is Harder to Manage In-House Than Most Practices Expect
Key Takeaways Nephrology practices carry some of the most documentation-intensive billing requirements in outpatient medicine, driven by CKD staging specificity, high-comorbidity E/M coding, and long-term patient management patterns. ICD-10 staging codes for chronic kidney disease directly affect medical necessity determinations — incomplete or unspecified staging is one of the most consistent sources of preventable denials […]