Pediatric Vascular Anomalies Program

Meet Our Team

The pediatric vascular anomalies team at Johns Hopkins All Children's includes experts from across specialties who work together to treat children and teens.

The Vascular Anomalies team at Johns Hopkins All Children’s Hospital uses a comprehensive approach that brings together specialists from multiple disciplines to address your child’s individual needs, often including:

  • Cardiology
  • Endocrinology
  • Gastroenterology
  • General Surgery
  • Genetics
  • Hematology/Oncology
  • Interventional Radiology
  • Neurosurgery
  • Ophthalmology
  • Orthopedics  
  • Otolaryngology 
  • Pathology
  • Physiatry  
  • Plastic and Reconstructive Surgery
  • Psychology
  • Pulmonology

Jennifer Mayer, M.D. Hematology / Oncology

Dr. Mayer specializes in pediatric hematology/oncology in the Johns Hopkins All Children’s Cancer & Blood Disorders Institute and is the lead hematologist of the Vascular Anomalies Program at the hospital. She served 21 years as medical director of Johns Hopkins All Children’s collaboration with Sarasota Memorial Hospital. She is author of more than 30 publications and two textbook chapters. She joined Johns Hopkins All Children's in 1996 and received the hospital's Best Consulting Physician Award in the 2017 Johns Hopkins Medicine Clinical Excellence Awards.
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S. Alex Rottgers, M.D. Plastic Surgery

Dr. Rottgers practices in the pediatric plastic and craniofacial surgery programs and is chief of the division of plastic and reconstructive surgery at Johns Hopkins All Children’s Hospital. His areas of special interest are vascular anomalies and in the treatment of cleft and craniofacial conditions including cleft lip and palate, craniosynostosis, hemifacial microsomia, microtia, and other abnormalities of the face and jaw.
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Mark Bittles, M.D. Radiology

Dr. Bittles is an interventional radiologist at Johns Hopkins All Children’s Hospital. He joined the hospital staff in 2015. Dr. Bittles earned his medical degree at University of Tennessee College of Medicine and completed his radiology residency and an interventional radiology fellowship at University of Washington Medical Center. He completed a pediatric radiology fellowship at Vanderbilt University Medical Center.
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Paul Danielson, M.D. Surgery - Pediatric

Dr. Danielson specializes in general surgery and serves as chief of the division of pediatric surgery at Johns Hopkins All Children’s Hospital. He was an early adopter of minimally invasive surgical techniques and has expertise in treating chest wall deformities. Dr. Danielson was named Johns Hopkins All Children’s Hospital physician of the year in the 2015 Johns Hopkins Medicine Clinical Excellence Awards. He joined the hospital staff in 2009. Dr. Danielson is director of innovative training and education at Johns Hopkins All Children's and an associate professor of surgery in the Johns Hopkins University School of Medicine. He retired as a colonel from the U.S. Army Reserve in 2017 after serving in both Iraq and Afghanistan.
View Paul’s Bio