Chapter 22: Pediatric Imaging

Detailed Chapter Overview

Chapter 22 provides an essential and comprehensive guide to the specialized field of pediatric imaging. Radiographing children is not simply "radiographing little adults"; it is a distinct discipline that requires a unique blend of psychological understanding, clinical knowledge, and technical expertise. The central theme of this chapter is that successful pediatric imaging hinges on two key factors: gaining the trust and cooperation of the child, and meticulously applying radiation protection principles. The chapter delves deeply into age-specific communication strategies, explaining how to approach infants, toddlers, and school-aged children to reduce fear and encourage cooperation. A significant portion is dedicated to the art and science of immobilization, detailing various techniques from simple sponges and parental assistance to specialized devices like the Pigg-O-Stat. The text provides a thorough exploration of pediatric-specific pathologies, such as epiphyseal plate fractures and ingested foreign bodies. The chapter places paramount importance on radiation safety, emphasizing the increased radiosensitivity of developing tissues. It provides detailed discussions on shielding, collimation, and the use of very short exposure times to minimize both patient dose and motion artifact. For every common pediatric examination, the chapter outlines specific procedural adaptations designed to produce diagnostic images efficiently and safely, ensuring the radiographer is equipped to handle the unique challenges and rewards of working with young patients.

In-Depth Study Guide

The Pediatric Patient: Understanding and Communication

The single most important factor in successful pediatric radiography is establishing rapport and minimizing fear. The approach must be tailored to the child's developmental stage.

1. The Parent's Role

• As an Ally: Parents can be your greatest asset. Speak to them first, explain the procedure, and enlist their help. A calm parent often leads to a calm child.
• As an Immobilizer: When appropriate and with proper shielding, a parent can assist in holding a child still. This is often more comforting for the child than mechanical restraints.
• Waiting Room Protocol: If possible, one parent should remain in the waiting room with other siblings to reduce distractions in the exam room.

2. Age-Specific Communication Strategies

• Infants (Birth to 1 year): They respond to a calm, soothing voice and being held securely. They are often startled by loud noises. Having pacifiers or a bottle ready can be helpful.
• Toddlers (1 to 3 years): This is often the most challenging age group due to their strong sense of autonomy and fear of strangers. Use simple, concrete words. "Picture" is better than "x-ray." Work quickly and efficiently.
• Preschoolers (3 to 5 years): They are curious and can be cooperative if you are honest and engaging. Let them see and touch the equipment. Praise and rewards (like stickers) are very effective.
• School-Aged Children (6 to 12 years): They are capable of understanding explanations. Explain what you are doing and why. Being honest about potential discomfort helps build trust.

Radiation Protection: The Foremost Priority

Children's cells are dividing more rapidly and are more sensitive to the effects of ionizing radiation than adult cells. Therefore, the principles of ALARA (As Low As Reasonably Achievable) must be applied with extreme diligence.

• Minimize Repeats: The best way to reduce dose is to get the image right the first time. This requires careful technique and effective immobilization.
• Shielding: Gonadal shielding is mandatory for all pediatric patients unless it obscures essential anatomy. For supine exams on females, place the shield over the pelvic region. For males, use a contact shield specifically covering the scrotum.
• Collimation: Always collimate tightly to the area of interest. Never use the full field size of the image receptor.
• Exposure Factors: Use the highest mA and the **shortest exposure time** possible. Short exposure times are critical not only for reducing dose but also for minimizing motion blur, which is the primary cause of poor image quality in pediatrics.

Immobilization: The Key to Sharp Images

Motion, both voluntary and involuntary, is the greatest enemy of diagnostic quality in pediatric imaging. Effective immobilization is crucial.

• Mummifying (Swaddling): A highly effective technique for infants and small children for exams of the skull or extremities. The child is wrapped snugly in a sheet or blanket to restrain their torso and limbs.
• Tape and Sponges: Can be used gently to help hold a limb or head in position. Never apply tape directly to the skin; fold it over so the sticky side is away from the patient.
• Pigg-O-Stat: A specialized, commercially available immobilization device for performing erect PA and lateral chest and abdomen radiographs on infants and toddlers (up to about age 3). It consists of a bicycle-style seat and clear plastic body clamps. While it ensures a perfectly erect position and frees the parents' and technologist's hands, it can be frightening for the child.
• Parental Assistance: A parent, wearing a lead apron and gloves, can hold their child's hands, legs, or head. This provides both immobilization and comfort.

Common Pediatric Radiographic Procedures

Chest Radiography

• Indications: Commonly performed to evaluate for aspiration, asthma, croup, cystic fibrosis, and other respiratory conditions.
• PA and Lateral Erect: The Pigg-O-Stat is the ideal tool for infants and toddlers. For older, cooperative children, standard erect techniques are used. A 72-inch SID is preferred to reduce heart magnification.
• AP Supine: For very ill infants or those in the NICU. The arms should be pulled up and out of the lung fields.

Skeletal Radiography

• Epiphyseal Plates: Radiographers must be aware of the presence of epiphyseal (growth) plates at the ends of long bones in children. These are radiolucent lines that can be mistaken for fractures by an inexperienced observer. Comparison views of the opposite, uninjured limb are often requested to differentiate between a normal growth plate and a fracture.
• Foreign Bodies: Common in children who ingest or aspirate small objects. AP and lateral views of the neck, chest, and abdomen are often required to locate the object.
• Non-Accidental Trauma (NAT) / Child Abuse: Radiography plays a critical role in the diagnosis of NAT. A skeletal survey, consisting of a specific series of images of the entire skeleton, is performed to look for multiple fractures in various stages of healing, which is a classic indicator of abuse. The radiographer must be professional, compassionate, and maintain confidentiality.

Abdomen and Gastrointestinal Studies

• AP Supine (KUB): A common exam to evaluate for constipation, bowel obstruction (e.g., intussusception), or to locate ingested objects.
• Voiding Cystourethrogram (VCUG): A fluoroscopic study of the bladder and urethra performed to investigate vesicoureteral reflux (the backward flow of urine from the bladder into the ureters), a common cause of urinary tract infections in children.