Our Team

Offering Experience in Clinical and Business Aspects of Medical and Radiation Oncology

RC Billing executives deliver knowledge from multiple sides of the medical and radiation oncology industry, with experience in both the clinical and business aspects of medical billing services. Their unique expertise at the corporate business level, along with backgrounds in cancer center development and management, is invaluable. Combine their practical, real-world experience in medical and radiation oncology billing and cancer center billing services with action-driven personalities, and it's clear that RC Billing executives are well-suited to turning profits for the progressive practice.


  • Ron DiGiaimo, MBA, FACHE
  • Chief Executive Officer

Before founding Revenue Cycle Inc. in 2002, Ron DiGiaimo worked as an executive with the three largest publicly traded oncology firms in the United States and currently lectures nationally on oncology-related topics. Recognizing a need for a "best of the best" practice reimbursement firm, he put together a team with an average of more than 24 years of diverse healthcare administration management experience. The Revenue Cycle Inc. team represents knowledge of consulting, auditing, training, billing and coding, reimbursement, electronic medical record conversion, program planning, corporate vendor relations, cancer center development and total operations for both freestanding oncology practices and hospital-based radiation and medical oncology clinics.

DiGiaimo himself brings impressive skills to the firm, including more than 27 years experience in clinical, mid-level and executive level management, an in-depth patient treatment experience as a past radiation therapist and radiographer, and a solid financial management background. He is also a proven strategist in practice building, medical coding and documentation for both Part A and Part B reimbursement and has broad experience with marketing, operations, development, and public relations.

Active with ACRO, ASTRO, SROA, ACCC, ACE, AAMD, ASCO, ACHE and several other such groups, DiGiaimo works tirelessly to forward the cause of oncology care. He currently assists with the publication of the American College of Radiation Oncology Practice Management Guide, which serves to educate all National Medical Directors from Medicare to commercial insurers as well as the oncology community. The guide contains information helpful to medical coding, reimbursement, practice valuation, marketing, new technology and many other items of interest.

DiGiaimo earned an MBA from Oklahoma Christian University and a Bachelors degree in Health Administration from Weber State University. He is also a past Radiation Therapist, trained at Allen Shivers Radiation Therapy School in Austin, Texas and has an Associates Degree of Radiography from MCC in Waco, Texas.

Perhaps most importantly, DiGiaimo prides himself on incorporating strong ethics and integrity into the management of Revenue Cycle Inc. and its affiliated companies. He recognizes the physicians and hospital administrators are the “drivers” of the business models and strives to help them reach their desired goals.

  • Mitzi Wilson
  • President

As President for RC Billing, Mitzi Wilson joins us with more than 25 years billing experience in Medical and Radiation Oncology. Mitzi is an oncology specialist in process improvement, coding, policy and procedure development and the entire revenue cycle. She brings efficiency and effectiveness to our operations in order to achieve maximum opportunity for our clients in a professional and results oriented manner while ensuring quality financial care for their patients.

Prior to joining the RC Billing team, Mitzi served as a National Reimbursement Manager for the largest publicly traded oncology firm in the United States providing Medical Oncology, Radiation Oncology, PET/CT, Diagnostic Radiology, Stem Cell Transplant and Oncology Research programs where she was responsible for more than $1 billion dollars in revenue annually. She has also served as an Executive Director of Reimbursement for a leading national third-party physician billing company where she was responsible for the operations of 7 multi-state billing entities providing billing services and technology platforms for over 3,500 multi-specialty physicians.

Mitzi also has vast expertise in the build out, development and operations of central billing offices in addition to physician practices. During her career, she has served as Chief Compliance Officer and been responsible for HIPAA and Compliance Training.

Executive Leaders

  • Patricia "Patti" O’Neill
  • Associate Director of Operations

Patti joins our team with 27 years’ experience in medical billing, accounting and management. As the Associate Director of Operations, Patti is responsible for oversight of the daily operations of Charge Entry and Cash Application. She works directly with clients to resolve billing issues promptly and with the utmost professionalism. Her experience in medical billing and accounting give Patti the advantage of understanding the financial aspect of billing in a timely manner.

Before joining our team, Patti served as the Controller and Director of Billing Operations for an OutReach Laboratory company on the West Coast. Patti obtained a bachelor’s degree in business management with an emphasis in accounting from The University of La Verne (Cum Laude). She has also completed several independent courses in medical billing, collections and management skills.

  • Karen Ryker, BA, CHC
  • Chief Compliance Officer and Client Resource Manager

Karen Ryker finds it advantageous to have worked from the ground up in radiation oncology because it gives her an edge in knowing, "Why are we here?" Her answer would be, "When you work face-to-face with the patient you realize every number represents an individual fighting for their life. It is our duty as healthcare professionals to make every effort to ensure the patient does not worry about the financial aspect of their treatment but are well informed in the process."

She finds radiation oncology coding challenging in the ever changing world of technology. Her past Regional Financial Manager role with a major radiation therapy company included training radiation oncology coders not only in coding and compliance but verification, pre-authorization, pre-determination and financial counseling. This makes for an educated liaison between RC Billing, physicians and their staff.

Obtaining a Bachelor of Arts in Healthcare Administration from Midway College combined with her 15 years of administrative experience in healthcare, Karen has an eye for processes in the clinical environment that can often deter patient growth, lack of reimbursement from insurance providers and possible missed revenue.

As Client Resource Manager, Karen looks forward to working each day with physicians, their staff and the RC Billing team to ensure the highest level of professionalism.

  • Donna Fleck
  • Credentialing/Contracting Manager

As the Credentialing/Contracting Department Manager, Donna Fleck oversees and provides direction for all RCB clients' payer credentialing and contracting/rate negotiation processes, including hospital privilege credentialing. The department utilizes credentialing software that provides reporting for expiring credentialing documents in addition to re-credentialing deadlines and payer fee schedule changes and updates. This department prides itself on being totally paperless, which ensures prompt response to payer requests for needed information. The department consists of multiple Credentialing/Contracting Reps and also Accounting Analytic Team. Donna ensures that all client payer contracts are executed at the highest possible reimbursement for client financial success.

Donna has been in the medical billing field for over 25 years. Her billing and credentialing/contracting background in Medical Oncology started 12 years ago and then progressed to Radiation Oncology. Donna has been both an Administrator over large practices, clinics and hospital business offices and Director of nationwide cancer center billing companies. Donna has been with RCB since 2004.

  • Connie Perry
  • Accounts Receivable Manager

Connie joins our team with 22 years billing experience in Medical, Gynecologic & Radiation Oncology. She is actively involved with the A/R team to maximize collections and provide daily guidance to ensure that A/R is worked timely and effectively enhancing the DSO.

Prior to joining RC Billing, Connie worked in all aspects of billing for a group of 20 physicians specializing in Medical Oncology, Gynecologic Oncology, Radiation Oncology, PET/CT, Stem Cell Transplant and Oncology Research protocols. During her tenure, she developed and implemented revenue cycle policies and procedures to streamline the operational processes starting at patient arrival through completion of treatment.

Connie has extensive experience in chart auditing, E&M auditing, coding and charge capture. She has experience credentialing new physicians, as well as existing physician re-credentialing, reviewing payer contracts and negotiations. Connie's philosophy is that her team is instrumental in navigating the complex insurance requirements to ensure that her clients and their patients can focus on treatment and the battle at hand.

  • Shannon Jordan
  • Accounts Receivable Manager

Shannon joins our team with 22 years of experience in healthcare accounts receivable resolution and management with a history of consistently meeting and exceeding revenue goals.

As Accounts Receivable Manager, Shannon is responsible for leading daily processes to ensure maximum reimbursement and timely resolution to outstanding AR, while enhancing the DSO. She works directly with payers to resolve issues identified during claim resolution in an effort to eliminate potential future issues. In addition, she is actively involved in the monitoring of new clients claim submission during the critical go-live processes to guarantee successful startup with accuracy, completeness and no payer issues.

Shannon has extensive experience in staff management and client relations. Shannon manages her team emphasizing exceptional financial care for the patients.

  • Barbara Paules
  • Accounts Receivable Manager

A consummate problem-solver and innovator, Barbara oversees the daily operation of the accounts receivable and patient services department. With 21 years of experience in accounts receivable resolution, she is a valuable resource for all Revenue Cycle Billing staff and clients seeking answers and solutions, tackling concerns effectively and promptly.

As A/R Manager, Barbara sees that daily, weekly and monthly A/R functions are performed accurately, including claim submissions, EDI reports and claim status. She ensures that patient collections policy and procedure is followed for all assigned clients, and she regularly interfaces with clients about their financials. Responsible for training all new hires on workflow process and systems, she is dedicated to making sure the highest standards of protocol are maintained.

Prior to joining Revenue Cycle Billing, Barbara worked for a large hospital-based organization supervising the contract compliance and appeals department.  She was instrumental in creating the appeals department workflow process that increased the overturn rate for denials, and received the Bill Aston award in finance for her accomplishments.

  • Rhonda McCalister
  • Credentialing/Contracting Team Lead

As the Team Lead, Rhonda plays a vital role in the overall daily functions of the medical oncology and radiation oncology credentialing/contracting department. She assists the department manager in daily oversight of all Revenue Cycle Billing clients' payer credentialing and contracting functions, including rate negotiation and hospital privilege reappointment. Department staff count on her as a resource for multi-state payer contracting to achieve the highest possible reimbursement for clients and to help them respond quickly to all client, payer and/or hospital requests. Rhonda also plays a key role in her colleagues’ ongoing credentialing and contracting training and education.

Prior to joining Revenue Cycle Billing in 2013, Rhonda worked in the diagnostic radiology industry, advancing from part-time receptionist to Director of Operations. She has delivered presentations at community functions, private physicians’ facilities and social services offices, and has worked in marketing in both hospital and physician environments. With a 30-year career in the medical field, she takes pride in her track record of cultivating relationships with clients, payers, vendors and colleagues to produce the highest level of customer service and revenue success.

  • Trina L. Dillard, RT(R)(T), CMD
  • Client Resource Manager

An energetic, efficient caregiver, Trina prides herself on bringing optimism to any environment. Her expertise ranges from radiation billing codes and guidelines for simulation, dosimetry and treatments to familiarity with the latest technology and equipment—knowledge she shares with physicians and their staff as Client Resource Manager.

Software, systems and equipment in Trina's portfolio include Varian Linacs, Exac trac, kv/conebeam, Radiocam, BAT, GE LightSpeed and Optima 580RT CT; Varian and Nucletron HDR; Eclipse, Brachyvision, and Oncentra treatment planning; Mosaiq; RadCalc; Mysis; and iKnowMed.

Trina began her career more than 25 years ago. She has held positions as an x-ray technologist, radiation therapist, and medical dosimetrist. She has served on the advisory and leadership council for US Oncology, and most recently held positions with Texas Oncology as Chief Radiation Therapist/Dosimetrist at a cancer center in Austin and San Marcos. She was also a clinical educator in radiation therapy for Texas State University for 15 years. In addition to working as a Client Resource Manager, she is the Virtual Simulation Education program manager for Texas State University. As a Program Development Faculty member, she is currently working on a project to develop teaching tools to implement a virtual linac “flight simulator” into the radiation therapy program’s curriculum.

Trina's professional memberships and certifications include the American Registry of Radiologic Technologists, the American Society of Radiologic Technologists, the Medical Dosimetrist Certification Board, and the Texas Department of Health. She studied radiation therapy at Washburn University and radiography at Labette Community College.

Team Members

  • Joel Barragan
  • Marketing & Communications Coordinator

An accomplished creative director and graphic designer, Joel manages marketing strategy and execution for Revenue Cycle Inc., The Oncology Group, Revenue Cycle Billing, and Infinity Oncology. He assists with the design and production of the companies’ websites as well as brochures, e-blasts and all other collateral. At the top of his priorities, however, is client service. Joel works closely with clients as well as attendees of Revenue Cycle Inc.’s year-round seminars, webinars and special events and ensures that the companies’ online Client Resource Center is up to date and working at peak performance.

Joel's design portfolio features an impressive range of work, from logos and identities to websites, wayfinding systems, books, and environmental projects. Prior to joining the Revenue Cycle Inc. team, Joel served as creative director of a consumer product company. Responsible for the overall look and feel of the brand, he directed everything from branding, graphic design and photography to advertising and marketing collateral. Under his watch, the company’s visibility increased sixfold.

Joel graduated from San Diego State University with a bachelor of arts degree in applied arts and sciences and an associate of arts degree in graphic design from San Diego City College.

  • Catherine Aline DiGiaimo
  • Director of Accounting

Catherine has a talent for building organizations, having created the financial division of both Revenue Cycle Inc. and RC Billing from scratch. Catherine is an active managing director and co-founder of Revenue Cycle Inc. and RC Billing, and created the human resource divisions for Revenue Cycle Inc., RC Billing, The Oncology Group and Infinity Oncology.

With a clinical background in patient treatments, simulations, and day-to-day operations of cancer centers, she has held operational positions in management and has served as a staff therapist.

Catherine attended The University of Texas School of Business. She also attended the University of Cincinnati Raymond Walters College Radiation Therapy Program. Catherine has been a registered radiation therapist since 1995. She is a member of the American Society of Radiologic Technologists and the American Registry of Radiologic Technologists.

  • Ron Goebel
  • IT Supervisor

As the IT supervisor for Revenue Cycle Inc., RC Billing, The Oncology Group and Infinity Oncology, Ron keeps the technological aspects of the offices running like clockwork. In addition to managing the efficient function of computers, servers and network infrastructure, Ron keeps the staff current with the most up-to-date software. His skills include graphic design, image manipulation and video editing. Ron also writes financial reports for RC Billing clients.

Ron is certified in CCNA Security, but with 15 years of experience working on computers has found himself to be his own best teacher.

The right side of Ron’s brain is as powerful as his left, evident from his creative pursuits. He is a photographer, artist, musician and loves films and games of all kinds.

  • Mary Racino
  • Director of Corporate Operations

Mary serves as Director of Marketing for Revenue Cycle Inc., The Oncology Group, Revenue Cycle Billing, and Infinity Oncology. In this role Mary is responsible for developing and executing marketing strategy, messaging and branding in addition to event marketing. She built and leads the marketing team, overseeing all aspects of marketing including online marketing, collateral, social media, events and the department budget.

Gaining maximum exposure of all four companies to best reach and serve oncology physicians, clinical staff, facilities, and other oncology-related entities is the goal that guides Mary and her team’s efforts. Always creating ways to ensure that her companies stand out among competitors, Mary builds programs using media that range from print to digital to event marketing.

Mary graduated from Concordia University in Austin, Texas with a bachelor of arts in elementary education and a minor in English.


Call 512.583.2000 or email info@rcbilling.com
to speak with an RC Billing expert.

“RC Billing clients appreciate that we can knowledgeably address their billing and compliance issues, offer strategic consultation when needed, give advice on important equipment purchases and factually discuss projected ROI values. Our clients’ business concerns are our concerns and delivering solutions is our number one priority.” Ron DiGiaimo, MBA, FACHE
President and CEO, RC Billing