Saturday, March 13, 2021

Cephalohematoma Case File

Posted By: Medical Group - 3/13/2021 Post Author : Medical Group Post Date : Saturday, March 13, 2021 Post Time : 3/13/2021
Cephalohematoma Case File
Eugene C. Toy, MD, Lawrence M. Ross, MD, PhD, Han Zhang, MD, Cristo Papasakelariou, MD, FACOG

Case 43
A male infant who weighs 3500 g appears icteric on examination. The previous day, the infant was delivered vaginally by vacuum-assisted extraction because there were severe fetal heart rate decelerations. The infant’s scalp has a 5-cm discolored soft tissue swelling that seems to be contained by and does not cross the sagittal or lambdoidal sutures. The mother had no prenatal or medical problems. There is no family history of bleeding disorders.

 What is the most likely diagnosis?
 What is the anatomical mechanism for the condition?


ANSWER TO CASE 43:

Cephalohematoma
Summary: On the previous day, a 3500-g male infant was delivered vaginally by
vacuum-assisted extraction. The infant appears icteric, and his scalp has a 5-cm
hematoma that is contained by and does not cross the sagittal or lambdoidal sutures.

• Most likely diagnosis: Cephalohematoma

• Anatomical mechanism for the condition: Injury to the branches of arteries supplying the lateral skull

CLINICAL CORRELATION
This 1-day-old infant was delivered with the aid of vacuum extraction and now has icterus and a discolored soft tissue mass that is contained within the sutures. This almost certainly represents a cephalohematoma. The more common caput succedaneum, which is swelling of the scalp soft tissue, is a normal response of the fetal head to the birth process. In this situation, the blood will cross over suture lines. When a soft tissue mass seems contained by suture lines, subgaleal cephalohematoma is suspected. The hemoglobin deposited in the hematoma becomes bilirubin, which is the reason for the infant’s icterus. A skull radiograph or CT scan is usually obtained to assess for skull fracture. Most of these hematomas will resolve with observation.


APPROACH TO:
The Scalp and Skull

OBJECTIVES
1. Be able to define the layers of the scalp
2. Be able to describe the structure of cranial sutures

DEFINITIONS
MAJOR SUTURES OF THE SKULL: The sagittal suture runs along the midline of the skull between the two parietal bones. The lambdoidal suture runs left to right posteriorly and separates the two parietal bones from the occipital bone. The coronal suture has the same course anteriorly and separates the frontal bone from the two parietal bones.

HEMATOMA: Pool of blood that accumulates in a tissue or space, usually clotted.

BILIRUBIN: Bile salt that is formed from the breakdown of hemoglobin by the liver. It usually accumulates in the gallbladder and is excreted into the small bowel to facilitate digestion. High levels of bilirubin in the blood give the skin and sclera of the eyeballs a yellowish tint (jaundice).

ICTERIC: Yellowish appearance of jaundice, in this case due to the local breakdown of bilirubin in the blood that has accumulated in the hematoma.

CAPUT SUCCEDANEUM: Edematous swelling of the superficial scalp due to the normal trauma of the birth process that resolves within 2 to 3 days.


DISCUSSION
The scalp is the unit of tissue that covers the calvaria. The tissue is composed of five layers and can be remembered by the acronym SCALP (Figure 43-1). Most superficial is the skin, which includes the dermis and the superficial fascia. Deep to that is a layer of dense connective tissue that binds tightly to the skin. The next layer is the aponeurosis of the occipitofrontalis muscle (galea aponeurotica). These three layers adhere tightly and move together as a unit. The fourth layer consists of loose connective tissue. The fifth layer is the periosteum, which covers the bone itself. The periosteum adheres tightly to the bone, especially in the region of

layers of the scalp

Figure 43-1. The layers of the scalp: 1 = skin, 2 = connective tissue, 3 = aponeurosis, 4 = loose connective tissue, 5 = periosteum, 8 = outer table of calvaria, 9 = diploĆ«, 10 = inner table of calvaria, 11 = endocranium. (Reproduced, with permission, from the University of Texas Health Science Center, Houston Medical School.)

the cranial sutures. The flexibility of the loose connective tissue allows the more superficial layers to move over the periosteum. In infants, the periosteum is adherent to the sutures.

The blood vessels that supply the scalp arise from branches of the internal and external carotid arteries. Anteriorly, these are the supraorbital and supratrochlear arteries, which are derived from the internal carotid. More laterally and posteriorly, the scalp is supplied by branches of the external carotid arteries. These include the superficial temporal arteries, which ascend in front of the auricle; and the occipital and posterior auricular arteries, which ascend posterior to the auricle. The arteries of the scalp are highly anastomotic. Therefore, after a laceration, blood may pulse from both ends of the cut artery.

The nerves of the scalp anteriorly originate from the first and third divisions of the trigeminal nerve. Medially, the supraorbital and supratrochlear nerves supply sensory innervation. Laterally, the auriculotemporal nerve provides sensory innervation. The posterior scalp is supplied medially by the posterior primary rami of cervical spinal nerves (C2, as the greater occipital nerve, and C3). Laterally, the skin is supplied by anterior primary rami that form the cervical plexus, in particular the lesser occipital and posterior auricular nerves.

Trauma to the scalp can damage blood vessels and hence cause a hematoma. The hematoma may spread within the same layer. Blood in the superficial fascia will migrate a little more slowly because of the septa within the subcutaneous fascia. In newborn infants, hematomas in this layer commonly result from the trauma of movement through the birth canal. Likewise, scalp trauma such as that induced by a suction-assisted delivery may occasionally injure the arteries within the periosteum, leading to accumulation of blood between the periosteum and the bone. Because the periosteum in infants adheres to the sutures, spread is impeded. A subcutaneous hematoma will cross sutures, but a subperiosteal hematoma will not. In adults, the loose connective layer is called the “danger space” because infection can easily migrate to the periorbital space. This is a dangerous condition because of the potential for spread into the cranium through the cavernous sinus.


COMPREHENSION QUESTIONS

43.1 Which of the following best describes the layers of scalp?
    A. Skin, aponeurosis, dense connective tissue, periosteum
    B. Skin, loose connective tissue, aponeurosis, periosteum
    C. Skin, dense connective tissue, aponeurosis, loose connective tissue, periosteum
    D. Skin, aponeurosis, loose connective tissue, muscle, periosteum

43.2 A 65-year-old woman complains of severe pain of the right side of the head. A vascular surgeon takes a biopsy of the artery deep to the temporalis muscle. Which of the following vessels did the surgeon most likely biopsy?
    A. Middle meningeal artery
    B. External carotid artery
    C. Ophthalmic artery
    D. Deep temporal artery

43.3 A neurologist uses a pin to test the sensation to a 26-year-old man’s scalp just near the hair line anteriorly. Which of the following nerves provides the innervation to the scalp in this region?
    A. CN V
    B. CN VII
    C. CN X
    D. Spinal nerve C2


ANSWERS
43.1 C. The layers of the scalp can be remembered by the mnemonic SCALP: Skin, Connective tissue, Aponeurosis, Loose connective tissue, Periosteum.

43.2 D. The temporal artery is deep to the temporalis muscle and sometimes is associated with inflammation (temporal arteritis). Temporal arteritis or giant cell arteritis is associated with headache and multiple joint pain.

43.3 A. The anterior scalp is innervated by CN V, whereas the posterior scalp is innervated by spinal nerve C2.


ANATOMY PEARL
 The blood vessels that supply the scalp are from branches of the internal and external carotid arteries.
 The sensory innervation of the scalp is by the trigeminal nerve: anteriorly by the supraorbital and supratrochlear nerves and laterally by the auriculotemporal nerve. The posterior scalp is innervated by spinal nerves C2 and C3. Spinal nerve C1 does not have a sensory component.
 The arteries of infants who undergo trauma, such as that induced by a suction-assisted delivery, may be damaged within the periosteum and develop a subperiosteal hematoma.

References

Gilroy AM, MacPherson BR, Ross LM. Atlas of Anatomy, 2nd ed. New York, NY: Thieme Medical Publishers; 2012:488−489, 516−517, 528−529. 

Moore KL, Dalley AF, Agur AMR. Clinically Oriented Anatomy, 7th ed. Baltimore, MD: Lippincott Williams & Wilkins; 2014:843−844, 856, 860−861. 

Netter FH. Atlas of Human Anatomy, 6th ed. Philadelphia, PA: Saunders; 2014: plates 3, 14.

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