Correct Answer: A. La d Cephalhematoma
Cephalhematoma is a subperiosteal collection of blood that occurs between the periosteum and the outer table of the skull bone, typically from birth trauma during delivery. The key discriminating feature is that it is always limited by the periosteal attachments to a single bone, never crossing the midline or suture lines. On X-ray, you may see a lenticular or lens-shaped density with well-demarcated borders corresponding to one cranial bone (commonly parietal). The clinical presentation—a firm, non-pitting swelling present since birth in a 2-month-old—is classic. Unlike caput succedaneum (which resolves within days) and subgaleal hematoma (which is life-threatening and crosses suture lines), cephalhematoma is self-limited, reabsorbs over weeks to months, and rarely requires intervention unless infected. The periosteal boundary prevents spread, making it the safest of the three hemorrhagic birth injuries. In Indian obstetric practice, cephalhematoma is the most common benign birth-related head swelling and typically requires only observation and reassurance to parents.
Why the other options are wrong
B. Subgaleal hematoma — This is wrong because subgaleal hematoma is a life-threatening emergency that bleeds into the potential space between the galea aponeurotica and periosteum, crossing multiple suture lines and the midline. It presents acutely with rapid head enlargement, signs of hypovolemia, and high mortality if untreated. A 2-month-old with a stable, chronic parietal swelling cannot have subgaleal hematoma—the timeline and clinical stability rule it out immediately. NBE may pair this with 'birth trauma' to trap students who don't distinguish severity. C. Caput succedaneum — This is wrong because caput succedaneum is a diffuse, pitting edema of the scalp caused by prolonged labor and negative pressure from the vacuum/forceps. It is not a true hematoma and resolves spontaneously within 24–72 hours of birth. A 2-month-old presenting with a persistent, firm parietal swelling cannot have caput succedaneum—the duration and character (firm vs. pitting) are incompatible. This is a classic NBE trap pairing all three birth-related scalp conditions. D. Encephalocele — This is wrong because encephalocele is a congenital defect (not a birth injury) in which brain tissue herniates through a skull defect, usually at the midline (occipital or frontal). It is present at birth but is a structural malformation, not a hemorrhagic collection. X-ray would show a bone defect, not a lenticular hematoma. The clinical context (birth trauma, parietal location, imaging appearance) excludes this developmental anomaly entirely.
High-Yield Facts
- Cephalhematoma is bounded by periosteal attachments to a single bone and never crosses suture lines—this is the key distinguishing feature on imaging.
- Resolves spontaneously over 2–8 weeks without intervention; calcification may occur but reabsorption is complete in most cases.
- Subgaleal hematoma is the life-threatening variant—crosses sutures, causes rapid head enlargement, hypovolemia, and requires urgent transfusion and neurosurgical evaluation.
- Caput succedaneum resolves within 72 hours and is pitting edema, not blood; cephalhematoma is firm and persists for weeks.
- Parietal bone is the most common site for cephalhematoma, followed by occipital; midline location suggests encephalocele, not cephalhematoma.
Mnemonics
CSE: Cephalhematoma, Subgaleal, Edema (Caput) Cephalhematoma = Bounded by bone, Subgaleal = Spreads across sutures (life-threatening), Edema (Caput) = Resolves in days. Use this to rank severity and timeline. Birth Scalp Injury Timeline Caput = Hours to 72 hours (pitting, diffuse). Cephalhematoma = Weeks to months (firm, single bone). Subgaleal = Hours to days (acute, life-threatening, crosses sutures).
NBE Trap
NBE commonly pairs all three birth-related scalp conditions in a single question to trap students who conflate them. The key discriminator is location (bounded vs. crossing sutures) and timeline (hours vs. weeks)—students who only remember "birth trauma" without these details will guess wrong.
Clinical Pearl
In Indian delivery settings, cephalhematoma is reassuring to parents because it is benign and self-resolving, unlike the alarming appearance of subgaleal hematoma. A simple rule: if the infant is clinically well at 2 months with a firm, localized parietal bump, it is cephalhematoma—observe and reassure. If the head swells acutely in the first 48 hours with signs of shock, suspect subgaleal hematoma and refer urgently.
_Reference: OP Ghai (Pediatrics) Ch. 3 (Neonatal Birth Injuries); Bailey & Love (Surgery) Ch. 40 (Head & Neck Trauma)_