What is the evaluation and treatment approach for a hard lump on the skull of a child?

Evaluation and Treatment of Hard Lumps on a Child's Skull

For a child presenting with a hard lump on the skull, computed tomography (CT) is the recommended first-line imaging modality when clinical assessment suggests potential intracranial injury or skull fracture. 1, 2

Initial Assessment

Clinical Evaluation

• Assess for:
  • History of trauma or injury
  • Duration and progression of the lump
  • Associated symptoms (headache, vomiting, altered mental status)
  • Consistency, mobility, and tenderness of the lump
  • Neurological symptoms
  • Signs of increased intracranial pressure

Risk Stratification

• High-risk features requiring immediate evaluation:
  • Glasgow Coma Scale (GCS) score less than 15
  • Altered mental status
  • Signs of basilar skull fracture
  • Severe headache
  • Persistent vomiting
  • Loss of consciousness > 5 seconds
  • Not acting normally per parent
  • Age < 2 years (higher risk group) 2

Diagnostic Approach

Imaging Selection

1. CT scan without contrast:

   • First-line imaging for suspected skull fracture or intracranial injury
   • Provides rapid assessment with excellent sensitivity for fractures and hemorrhage
   • Should use dedicated pediatric protocols with parameters tailored to patient size 1
   • Multiplanar and 3D reconstructions increase sensitivity for fractures 1

2. MRI:

   • Not recommended for routine acute evaluation 1
   • Consider for follow-up or when CT findings are equivocal
   • Better for identifying small bleeds, particularly in posterior fossa or brainstem
   • May require sedation in young children due to longer acquisition time 1

3. Skull radiographs:

   • Should NOT be used for diagnosis of pediatric skull lesions or screening for intracranial injury 1
   • Limited sensitivity (only 63%) for diagnosing skull fractures 1
   • Cannot detect intracranial injuries 1

Common Etiologies of Hard Skull Lumps in Children

Based on pathological findings, the most common causes include:

• Epidermoid/dermoid cysts (most common benign skull lesions) 3
• Langerhans cell histiocytosis 3
• Intraosseous hemangioma 3
• Osteoblastoma 3
• Myofibroma/fibroma 3
• Skull fractures with callus formation
• Malignant lesions (rare, ~8% of cases) 4

Treatment Approach

For Traumatic Etiology:

• For minor head trauma with no concerning features:

  • Observation and symptomatic management
  • Parent education on warning signs
  • Follow-up as needed

• For confirmed skull fracture:

  • Neurosurgical consultation
  • Admission for observation if:
    • Age < 1 year
    • Depressed or comminuted fracture
    • Associated intracranial injury
    • Concern for non-accidental trauma

For Non-traumatic Skull Lesions:

• Benign-appearing lesions:

  • Consider surgical excision for diagnosis and treatment 5
  • Complete surgical resection is curative in most cases (43/48 patients) 5

• Suspicious for malignancy:

  • Multidisciplinary approach involving neurosurgery, oncology, and radiation oncology
  • Surgical resection when feasible 4
  • Adjuvant therapy based on histopathology

Follow-up and Monitoring

• For traumatic injuries:

  • Parental monitoring for 48-72 hours
  • Return for worsening symptoms
  • Follow-up imaging as clinically indicated

• For benign lesions:

  • Follow-up after surgical excision
  • Low recurrence rate following complete resection 3

Important Considerations

• Intracranial extension of skull lesions is rare in children 3
• Recurrence is uncommon following complete surgical resection 3
• Consider non-accidental trauma when mechanism of injury is unclear or inconsistent with injury pattern 2
• Malignant skull lesions are rare in children (only 5/65 in one series) 5

Pitfalls to Avoid

• Relying on skull radiographs for diagnosis (insufficient sensitivity)
• Delaying imaging in high-risk patients
• Failing to consider non-accidental trauma in infants and young children
• Missing signs of intracranial involvement in skull lesions

Remember that while most pediatric skull lesions are benign, proper imaging and evaluation are essential for accurate diagnosis and appropriate management.