Isolated synostotic plagiocephaly (ISP) presents as an oblique head as a consequence of an anomalous unilateral fusion of the coronal or the lambdoid suture [1]. In both cases, a palpable ridge will develop over the site of premature suture fusion [2]. Unilateral coronal synostosis is associated with anterior ISP while posterior ISP is caused by an early fusion of the lambdoid suture [3]. ISP affects approximately 1/100000 infants [4].

The genetic role in ISP is still in the focus of medical research. Rare mutations in the FGFRs, TWIST1, LRIT3, ALX4, IGFR1, EFNA4, RUNX2, and FREM1 genes may play a role for isolated ISP [3] [5] [6].

Anterior ISP-associated deformities include a flattening of the frontal bone and of the ipsilateral orbital rim in combination with a contralateral frontal bossing. In 50-60% of cases, strabismus is found as a consequence of anatomical changes in the orbital roof. Anterior ISP can also lead to a deviation of the skull base, a positional change of orbits, eyebrow and ear asymmetries, as well as mandibular deviations with malocclusion [3] [7] [8].

Posterior ISP leads to a trapezoid head shape with occiput flattening and malpositioned ears. Moreover, early lambdoid suture synostosis is linked to debilitating changes in the posterior fossa. Most notable findings in this context include an Arnold-Chiari malformation type 1 and a fusion of the jugular foramen. Thus, posterior ISP predisposes the patient for intracranial hypertension [9] [10].

ISP diagnosis relies on clinical findings and a thorough analysis excluding other potential causes of plagiocephaly. Plagiocephaly is clinically diagnosed by the typical formation of a parallelogram defined by ear and maxilla positions [1].

Positional plagiocephaly (PP) often occurs concomitantly with torticollis and produces stronger facial asymmetries [1] [11] [12]; ISP is most easily identified by the posterior malpositioning of the ear on the affected side. On the other hand, PP produces anteriorly malpositioned ears [2]. Syndromic plagiocephaly is usually accompanied by developmental retardation [13].

The use of computed tomography (CT) imaging is only indicated in case of an ISP suspicion, particularly if infant repositioning does not improve cranial asymmetry over weeks. CT findings can also be used in preparation for a surgical intervention aimed to avert an increased risk of intracranial hypertension (ICH) or to correct the plagiocephaly-caused malocclusion. If ICH has already developed, appropriate immediate countermeasures are indicated [1] [14].

Treatment for plagiocephaly often involves conservative measures. Repositioning techniques, such as alternating the infant's head position during sleep and encouraging tummy time while the infant is awake, can help. In more severe cases, a custom-fitted helmet may be recommended to gently shape the skull over time. These helmets are typically worn for several months and are most effective when started between 4 and 12 months of age.

The prognosis for infants with plagiocephaly is generally excellent. With appropriate management, most children experience significant improvement in head shape. The condition does not affect brain development, and long-term complications are rare. Even without treatment, many cases improve as the child grows and becomes more mobile.

Plagiocephaly is often caused by external pressures on the infant's skull. This can occur due to prolonged time spent lying on the back, which is common in infants who sleep in the same position. Other contributing factors include torticollis (a condition where neck muscles are tight, causing the head to tilt) and premature birth, as premature infants have softer skulls and may spend more time in one position.

Plagiocephaly has become more common since the "Back to Sleep" campaign, which encourages parents to place infants on their backs to sleep to reduce the risk of sudden infant death syndrome (SIDS). It is estimated that up to 20-30% of infants may develop some degree of plagiocephaly. The condition is more prevalent in males and in first-born children.

The pathophysiology of plagiocephaly involves the deformation of the skull due to external forces. An infant's skull is composed of several bones that are not yet fused, allowing for growth and development. When consistent pressure is applied to one area, it can lead to flattening. Unlike craniosynostosis, the sutures (joints between skull bones) remain open in plagiocephaly, allowing for normal brain growth.

Preventing plagiocephaly involves minimizing prolonged pressure on any one part of the infant's head. Parents can encourage varied head positions during sleep and provide supervised tummy time when the infant is awake. Using a supportive pillow or mattress designed to reduce pressure on the skull can also be helpful. Regularly changing the infant's position in the crib and during feeding can further reduce the risk.

Plagiocephaly is a common condition in infants characterized by an asymmetrical head shape. It is primarily a cosmetic issue and does not affect brain development. Diagnosis is based on physical examination, and treatment often involves repositioning techniques or helmet therapy. The prognosis is excellent, with most cases improving over time. Preventive measures can help reduce the risk of developing plagiocephaly.

For parents and caregivers, it's important to know that plagiocephaly is a common and manageable condition. If you notice a flat spot on your infant's head, consult with a healthcare provider for an evaluation. Simple measures like changing your baby's head position and encouraging tummy time can make a significant difference. In some cases, a helmet may be recommended to help shape the skull. Remember, plagiocephaly does not affect your child's brain development, and with appropriate care, most children experience improvement.

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