The differential diagnosis of abnormal head shapes: separating craniosynostosis from positional deformities and normal variants

Computed tomography quantitative analysis of cranial vault dysmorphology and severity of facial complex changes in posterior synostotic plagiocephaly patients

BACKGROUND

Posterior synostotic plagiocephaly (PSP) impacts craniofacial skeleton. Study quantifies facial changes in children with PSP to investigate the impact of age and PSP severity at diagnosis on the facial dysmorphology.

MATERIAL AND METHODS

High-resolution preoperative CT images of 22 infants with PSP were analyzed. They were divided according to the early or late age at time of diagnosis. Each group was further subdivided according to the severity of PSP evaluated by the cranial vault asymmetry index (CVAI): mild-moderate PSP (CVAI between 3 and 12%) and severe PSP (CVAI > 12%). Analysis of the facial complex was performed. Each group was compared with age-matched healthy subjects.

RESULTS

All children exhibited unilateral lambdoid suture synostosis. The "early" diagnosis group consisted of 7 children with mild-moderate PSP while the "late" diagnosis group of 15 children in which 6 children had mild-moderate and 9 children severe PSP. All children showed altered position of glenoid fossae and mandibular asymmetry characterized by reduced mandibular diagonal distance length on the affected side while the subgroup of children with severe PSP detected in "late" diagnosis group had also altered mandibular inclination and reduced midfacial depth on both sides.

CONCLUSIONS

PSP causes cranial base dysmorphology which drives changes in facial complex growth; the severity of facial changes mainly depends on the severity of cranial vault dysmorphology detected by CVAI. Mandible reshapes early under the stress of altered biomechanical forces of the skull base while changes in the maxilla are secondary to the asymmetric growth of the mandible and occur only in severe cases.

Another look at “tummy time” for primary plagiocephaly prevention and motor development

It is three decades since it was recommended that infants sleep on the back to reduce risk of sudden unexpected infant death (SUID). The SUID prevention program is known as "back to sleep" or "safe sleeping", and this initiative is not questioned. Sleeping on the back is associated with, but not the cause of, the development of infant positional plagiocephaly, also known as deformational or a non-synostotic misshapen head when the skull sutures are open, not fused. This paper provides a synthesis of the history and impact of positional plagiocephaly. It includes a scoping review of plagiocephaly prevention facilitating motor development and reveals few articles on primary prevention which aims to prevent it developing in the first place. It is concerning that preschool-aged children with a history of infant plagiocephaly continued to receive lower developmental scores, particularly in motor development, than unaffected controls, and this may be a marker of developmental delay. Tummy-time (prone) for play is the mainstay of plagiocephaly prevention advice to minimize development of plagiocephaly and to facilitate infant motor development, particularly head control. While tummy-time has shown benefit for infant development, there is limited evidence of its effectiveness in preventing plagiocephaly and some evidence that it promotes only prone-specific motor skills. Most of the published literature is concerned with treatment post-diagnosis, in the form of reviews, or clinical notes. There is a plethora of opinion articles reinforcing tummy-time from birth for plagiocephaly prevention. The review shows that there are gaps in advice for early infant development of head control. An accepted test of head control in infants is "pull to sit" from supine which demonstrates antigravity strength of the neck flexors and coordination of the head and neck when the infant is drawn to sit from supine. This motor skill was cited as achievable by 4 months in the earliest paper on plagiocephaly in 1996. Physical therapists and others should revisit the mechanism of early infant head control development against gravity, particularly antigravity head, neck and trunk coordinated flexion movement in supine, as there has been little attention to early facilitation of this motor skill as a plagiocephaly prevention strategy. This may be achieved by considering "face time" as well as tummy time for primary prevention of plagiocephaly.

[Difficulties in differential diagnosis of sagittal synostosis (scaphocephaly)]

Craniosynostosis is characterized by congenital absence or premature closure of skull sutures. The most common form of craniosynostosis is synostosis of sagittal suture followed by scaphocephaly. There are some head deformities similar to scaphocephaly such as positional and constitutional dolichocephaly, etc. These patients have no sagittal suture synostosis. However, there are difficulties in differential diagnosis between these deformities and scaphocephaly.

OBJECTIVE

To develop differential diagnostic criteria between dolichocephalic head deformities and true scaphocephaly following sagittal synostosis.

MATERIAL AND METHODS

The study included 33 patients with dolichocephaly (25 (75.8%) boys and 8 (24.2%) girls) between December 2013 and August 2022. The inclusion criterion was available CT or ultrasound data confirming or excluding sagittal synostosis. Age of patients was 8.62±7.71 (1.77-36) months. We analyzed anamnestic, clinical and radiological data. Radiological data was compared with diagnostic findings in 20 patients with scaphocephaly. Both groups were comparable in age, gender and cranial index.

RESULTS

We present clinical and radiological signs, as well as algorithm for differential diagnosis between scaphocephaly and dolichocephaly.

CONCLUSION

There are objective difficulties in differential diagnosis between scaphocephaly following sagittal synostosis and dolichocephalic head deformities. In most cases, we cannot establish the cause of congenital forms of dolichocephaly. The most likely causes may be pre- and postnatal compressive and positional effects. Ultrasound of skull sutures is preferable for differential diagnosis between these abnormalities. Correction of dolichocephaly can be carried out according to aesthetic indications with individual cranial orthoses.

Positional Plagiocephaly and Craniosynostosis

Along with the decrease in sudden infant death syndrome due to the successful "Back to Sleep" Campaign, there was a reciprocal increase in cases of positional plagiocephaly (PP). The prevalence of PP significantly rose from approximately 5% to upward of 46% at age 7 months. Consequently, clinicians have seen a surge in the number of patients presenting with head shape abnormalities. Not only does this increase in patient volume pose a logistical problem to clinics, but it also poses a potential risk to patients with craniosynostosis, whose head shape anomalies are similar to a "needle in a haystack" of patients with more common PP. This review explores the causes, risk factors, and treatment options of PP and craniosynostosis, along with the differential of head shape anomalies based on phenotypic presentation. In doing so, we hope to provide pediatric care clinicians with the tools necessary to effectively evaluate and manage patients with head shape abnormalities. [Pediatr Ann. 2023;52(1):e10-e17.].

Rotation Advancement Distraction Osteogenesis Technique is Attributed to Unilateral Lambdoid Synostosis and is Used to Correct Posterior Plagiocephaly

Unilateral lambdoid synostosis is the rarest form of craniosynostosis. Surgical correction is technically challenging from a morphological standpoint and is used to decompress intracranial pressure. Herein, the authors present a "rotational advancement bone flap" technique for the repair of posterior plagiocephaly. A bicoronal skin incision was performed, to expose the occipital region. The rotational advancement bone flap was designed to hinge off the nonsynostotic side, and it was set up to include an occipital protrusion on the normal side. On the premature side, an advancement bone flap was set up to include the flattened and deformed occipital bone. A titanium cranial distractor, which was attached between the bone flap and the anterior bone. An absorbable plate, which would later become a hinge due to the movement of the bone flap, was attached to the area for reinforcement. The authors technique was able to decompress intracranial pressure with satisfactory esthetic outcomes.

Fronto-Orbital Advancement for Metopic and Unilateral Coronal Craniosynostoses

Fronto-orbital advancement remains a powerful technique for the correction of anterior cranial vault differences related to metopic (trigonocephaly) or unilateral coronal (anterior plagiocephaly) craniosynostoses. Traditional fronto-orbital advancement requires access to the forehead and superior 2/3 of the orbit via a coronal incision. The frontal bone and orbital segment (bandeau) are then separated from the skull and reshaped. In patients with metopic craniosynostosis, the bandeau and frontal bone will need to be advanced and widened. In patients with unilateral coronal craniosynostosis, the bandeau will need to be "untwisted" to address the supraorbital retrusion on the affected side, the affected orbit will need to be shortened and widened, and the frontal bone flap will need to be proportionately advanced on the affected side. Overcorrection of the affected dimension should be undertaken to account for growth and relapse.

Epidemiology, Genetics, and Pathophysiology of Craniosynostosis

Craniosynostosis, the premature fusion of the infant cranial skulls, can be recognized by characteristic head shape differences that worsen with head growth. Craniosynostosis can be syndromic or nonsyndromic and can involve one suture or multiple sutures. Timely cranial vault surgery is recommended to expand and reshape the skull, with a goal of preventing increased intracranial pressure and providing sufficient space for brain growth. Several gene variants and environmental exposures are known to increase the risk of single suture craniosynostosis (SSC), including in utero constraint, exposure to specific toxins and medications, and medical conditions such as thyroid dysregulation and metabolic bone disorders.

Management of Sagittal and Lambdoid Craniosynostosis: Open Cranial Vault Expansion and Remodeling

The prevalence of sagittal and lambdoid suture craniosynostosis differs considerably, as they are notably the most and least prevalent sutures involved in isolated suture craniosynostosis, respectively. The goals of reconstructing the cranial vault in both entities is the same: to release the fused suture, expand cranial volume, restore normal head shape and morphology, and allow for normal growth of the cranial vault. With regards to sagittal suture synostosis, opinions vary on whether reconstruction should focus on either the anterior or poster cranial vault. In contrast, the poster cranial vault is always targeted in lambdoid suture craniosynostosis.

Distinguishing Between Lambdoid Craniosynostosis and Deformational Plagiocephaly: A Review of This Paradigm Shift in Clinical Decision-Making and Lesson for the Future

The cause of occipital asymmtery can be either extrinsic or intrinsic. Intrinsic causes include lambdoid craniosynsotosis. This condition is generally treated with cranial vault expansion surgery. Extrinsic causes include deformational plagiocephaly, which became commonplace after the "Back to Sleep Campaign" instituted in the 1980s by the American Academy of Pediatrics. The treatment of this condition is non surgical. Dr. Joseph Gruss was instumental in differentiating between these conditions and reducing the number of unnecessary surgeries that were previously being performed.

Perceptions and Preferences of Laypersons in the Management of Positional Plagiocephaly

BACKGROUND

Uncertain clinical evidence for treating positional plagiocephaly, especially with helmet therapy, creates difficulties in counseling parents of patients. This study investigates layperson perceptions and treatment preferences for positional plagiocephaly to provide patient-oriented evidence for management.

METHODS

Adult laypersons were recruited through crowdsourcing to view digitally-modified images of normal, mildly, moderately, or severely plagiocephalic infant heads. Participants provided demographic information and rated the infant's head shape and potential related social difficulties, likelihood of consulting a physician for treatment options, and likelihood of seeking helmeting treatment for the infant.

RESULTS

Nine hundred forty-five individuals participated in the study. Perception of head shape, prediction of future embarrassment and social difficulties, likelihood of seeking physician evaluation, likelihood of choosing helmet therapy, and willingness-to-pay for helmet therapy were pairwise-different between 4 plagiocephaly severities (corrected-P < 0.001 for all), except between normocephaly (n = 194) and mild (n = 334) plagiocephaly or between moderate (n = 203) and severe (n = 214) plagiocephaly. Younger respondents were more likely to consult a physician (uncorrected-P = 0.016) and choose helmet therapy (uncorrected-P = 0.004) for infants with normocephaly or mild plagiocephaly. Parents of children with physical disabilities were 6 times as likely as other participants to choose helmet therapy for mild plagiocephaly (corrected-P = 0.036).

CONCLUSIONS

Laypersons perceived moderate and severe plagiocephaly as equally abnormal and mild plagiocephaly as normal, consistent with their treatment preferences. Parents of physically disabled children were significantly more likely than other participants to choose helmet therapy. Our findings provide medical professionals with lay perspectives on positional plagiocephaly that may facilitate effective counseling of parents.

Treatment of Deformational Plagiocephaly With Physiotherapy

Non-synostotic plagiocephaly consists in an asymmetry of the skull due to mechanical forces applied in utero or postnatally: main differential diagnosis is with true synostotic asymmetry, which is caused by the premature closure of a suture. The correction of positional forms is mostly conservative, with 3 main strategies: counterpositioning, physiotherapy and helmet therapy. There is no synthesized evidence on which is the most effective. The Authors evaluate the modification of antropometric measurments before and after a pediatric physical therapy program in a sample of patients with non-synostotic skull asymmetry, in order to evaluate the improvements in the skull shape. The hypothesis being tested was that physical therapy alone could improve the antropometric measurments. The authors enrolled in this study 24 patients diagnosed of non-synostotic asymmetry, clinically and with ultrasound, referred to the Maxillo-facial Unit of Policlinico Umberto I, Rome, within 2013 and 2016. A standardized pediatric physical therapy intervention program was designed: it consisted in a combination of excercises and manipulative procedures to reduce positional preference, musculoskeletal disorders and cranial deformity. Infants received 16 sessions of physical therapy, of 40 minutes each, once a week, for four months. The Authors evaluate the variation of four anthropometric measurments, performed before and after the physical therapy program: Argenta scale, Oblique Diameter Difference Index (ODDI), Cranial Proportional Index (CPI) or Cephalic Ratio (CR), Cranial Vault Asymmetry Index (CVAI). Craniometric evaluations were extrapolated by standardized 2D digital photographs of frontal, sagittal and transverse planes, by the same physician to minimize bias. The management of positional cranial deformities is still controversially discussed and especially the effects of physiotherapy and osteopathy have been only marginally researched. Statistical analysis revealed the effectiveness of the protocol: all anthropometric measurements improved with a high rate, major in youngest children (P < 0.5) and in more severe first presentations (P < 0.05 or P < 0.01). The results suggest manipulative approach may improve the outcome in the long term follow up of cranial asymmetries.

Imaging in craniosynostosis: when and what?

PURPOSE

Currently, the interest on craniosynostosis in the clinical practice is raised by their increased frequency and their genetic implications other than by the still existing search of less invasive surgical techniques. These reasons, together with the problem of legal issues, make the need of a definite diagnosis for a crucial problem, even in single-suture craniosynostosis (SSC). Although the diagnosis of craniosynostosis is primarily the result of physical examination, craniometrics measuring, and observation of the skull deformity, the radiological assessment currently plays an important role in the confirmation of the diagnosis, the surgical planning, and even the postoperative follow-up. On the other hand, in infants, the use of radiation or the need of sedation/anesthesia raises the problem to reduce them to minimum to preserve such a delicate category of patient from their adverse effects.

METHODS, RESULTS AND CONCLUSIONS

This review aims at summarizing the state of the art of the role of radiology in craniosynostosis, mainly focusing on indications and techniques, to provide an update not only to pediatric neurosurgeons or maxillofacial surgeons but also to all the other specialists involved in their management, like neonatologists, pediatricians, clinical geneticists, and pediatric neurologists.

Relationship of a Metopic Ridge and Anterior Cranial Volume Measured by a Noninvasive Laser Shape Digitizer

Cranial dysmorphology observed in patients with metopic craniosynostosis varies along a spectrum of severity including varying degrees of metopic ridging, bitemporal narrowing, and trigonocephaly. Management has been based upon the subjective clinical impression of presence and severity of trigonocephaly. Severity of cranial dysmorphology does not predict the occurrence or severity of associated abnormal neurodevelopment, as children with mild-to-moderate trigonocephaly may also experience developmental delays. The authors sought to determine the relationship between mild-to-moderate trigonocephaly and anterior cranial volume using a noninvasive laser shape digitizer (STARscanner) in patients with abnormal head shape.An IRB-approved retrospective review of a prospectively maintained database and medical records was performed. Two hundred three patients less than 1 year of age with abnormal head shape were categorized as having a metopic ridge with mild-to-moderate trigonocephaly, metopic ridge without trigonocephaly, or no ridge. Measurements of cranial volume, circumference, and symmetry were calculated by the STARscanner, which quantifies three-dimensional shape of the cranial surface. Measures were analyzed using a series of analyses of variance and post-hoc Tukey honest significant difference.The authors results showed ACV was significantly reduced in patients with mild-to-moderate trigonocephaly compared with those without metopic ridge (P = 0.009), and trended toward significance compared with those with a ridge but without trigonocephaly (P = 0.072). The ratio of anterior-to-posterior cranial volume was significantly reduced in those with mild-to-moderate trigonocephaly compared with those without metopic ridge (P = 0.036).In conclusion, patients with milder anterior cranial deformities demonstrated an association between a metopic ridge with mild-to-moderate trigonocephaly and reduced anterior cranial volume.

Defining and Correcting Asymmetry in Isolated Unilateral Frontosphenoidal Synostosis: Differences in Orbital Shape, Facial Scoliosis, and Skullbase Twist Compared to Unilateral Coronal Synostosis

INTRODUCTION

Isolated frontosphenoidal synostosis (FS) is a rare cause of fronto-orbital plagiocephaly that can be challenging to distinguish from isolated unicoronal synostosis (UC). The purpose of this paper is to analyze differences in fronto-orbital dysmorphology between the 2 conditions, to describe approaches for surgical correction, and to report surgical outcomes between FS and UC patients in a casecontrol fashion.

METHODS

Patients treated for craniosynostosis over a 12-year period at our institution were retrospectively evaluated under institutional review board approval. Frontosphenoidal synostosis patients who underwent bilateral fronto-orbital correction of anterior plagiocephaly with minimum 2-year follow-up, adequate pre-, and minimum 2-year postoperative computed tomography scans were included in the case-control portion of the study. These patients were randomly age-matched to UC patients meeting the same inclusion criteria. Preoperative and postoperative orbital shape and volumetric analysis was performed using Mimics software.

RESULTS

Twelve FS patients were treated during the study period. Seven of these patients met casecontrol inclusion criteria with average follow-up of 47.5 months. The characteristic FS orbit was a relatively wide, short, and shallow trapezoid, while the characteristic UC orbit was a relatively narrow, tall, and deep parallelogram. Frontosphenoidal synostosis orbits were significantly wider, shorter, shallower, and smaller than UC orbits. Surgical correction tailored to the differential dysmorphologies resulted in statistical equalization of these differences between affected and contralateral control orbits at follow-up, with the exception of UC orbital width, which remained significantly narrower than unaffected contralateral control. One patient in each group required cranioplasty for skull defects at follow-up, while no patient underwent surgical readvancement.

CONCLUSIONS

Frontosphenoidal synostosis and UC orbital shape differ significantly, and can be normalized using fronto-orbital advancement tailored to the distinct orbital dysmorphologies of these 2 groups.

Occipital Plagiocephaly

After the “Back to Sleep” campaign, promoted in 1992 by the American Academy of Paediatrics to prevent the Sudden Infant Death Syndrome (SIDS), it was recommended to place babies in a supine sleeping position. The incidence of SIDS has fallen dramatically since 1992, whereas there has been a major increase in the incidence of occipital plagiocephaly (OP). We report the data relative to the OP cases observed in the Paediatric Department of Padua Hospital between 1998 and 2003. 122 (63%) of the 194 cases of craniosynostosis observed presented OP. The 64 children that took part to the study were contacted and underwent neurological examination with an evaluation of skull shape and previous radiograms. We proposed to parents a questionnaire to define the risk factors and estimate the skull deformity over time. 58 of the 64 children presented positional plagiocephaly (PP), six had synostotic plagiocephaly (SP). Since 1998 there has been a progressive increase in cases of PP. There is a male prevalence (65%), but no side prevalence. Firstborns accounted for 33 (51%), whereas 11 were preterm infants (17%). 82% had a gestational age between the 38th and 40th week. The mean value of the Apgar Index was 8 at the first minute and 9 at the 5th minute. At birth the clinical presentation was: occipital flattening already present at birth in 23 children, preferential head orientation in 18, congenital torticollis in 12, ear asymmetry in 12, frontal bossing in ten. We noticed a mild developmental delay in 8 children (13%). The maximum degree of cranial asymmetry was observed in two peaks in cases of PP: at the third and fourth months (34 cases) and then at the sixth and seventh months (13 cases). The SP presented a progressive exacerbation of the deformity until surgery (done at the sixth to seventh months). PP improved by hygienic postural norms in six months; only three patients required surgery for aesthetic reasons. We observed a strict correlation between side of flattening and sleep head position ( χ2 test, p-value=2,256e-09) and a higher degree of occipital flattening at birth in patients with associated congenital torticollis (Mann-Whitney test, p-value=0.002744). In conclusion, OP is a common condition but essentially benign; it does not cause medical consequences but aesthetic problems. It is necessary to recognize the mild deformity in the newborns so as to intervene early with hygienic postural norms that can correct the asymmetry. The diagnosis is largely clinical and only in case of doubt are radiological examinations required (ultrasonography for sutures, 3D CT scans).

Diagnostic Yield of Routine Skull Radiographs in Infants With Deformational Plagiocephaly

OBJECTIVE

Differentiating synostotic and nonsynostotic plagiocephaly can be challenging, and many providers routinely obtain screening skull radiographs when evaluating an infant with plagiocephaly. However, the diagnostic yield of radiographs has not been studied in this clinical setting.

DESIGN

This study was a retrospective chart review.

SETTING

The study took place in a tertiary care center.

PATIENTS

We retrospectively reviewed the records of all patients referred to Children's Medical Center (Dallas, TX) between the years 2010 to 2012 with a diagnosis of plagiocephaly. After an initial evaluation, skull radiographs were obtained to rule out craniosynostosis. We reviewed clinical and demographic data and radiographic findings to determine the diagnostic yield of routine screening radiographs in infants presenting with plagiocephaly.

RESULTS

There were 1219 patients in total, and 1213 of these patients received screening four-view conventional skull radiographs. Six had computed tomography without prior radiographs. Of the patients in the skull radiograph group, 24% (289 of 1213) had abnormal radiographic findings, and 7.6% of this group (22 of 289) had findings that were indicative of craniosynostosis. Of these 22 patients, 12 obtained follow-up studies, and only three patients (0.2% of skull group) had true craniosynostosis. In comparison, 50% (three of six) in the group of patients who underwent computed tomography without prior conventional screening radiographs had true craniosynostosis.

CONCLUSIONS

Routine screening skull radiographs have a low diagnostic yield in differentiating between synostotic and nonsynostotic plagiocephaly in patients presenting to a tertiary care deformational plagiocephaly clinic. Considering the costs and radiation exposure, the benefit of the routine use of skull radiographs in patients with deformational plagiocephaly is questionable.

Early neurodevelopment in infants with deformational plagiocephaly

The objective of this study was to characterize the early neurodevelopmental profile of Australian infants with deformational plagiocephaly (DP). Twenty-one infants with a confirmed diagnosis of DP (mean age, 7.9 months; SD, 2.0 months) were assessed on the Bayley Scales of Infant Development, Second Edition, before treatment. As a group, infants with DP showed significantly weaker motor skills compared with the normative population. Patients with DP did not significantly differ from normative population estimates with respect to cognitive abilities. Males with DP displayed significantly reduced motor abilities compared to females. These findings do not suggest that DP causes developmental problems, but DP could be a marker for risk of developmental problems. Screening for developmental concerns in infants with DP is therefore important.

Lambdoidal synostosis in dizygotic twins with a family history of an undiagnosed connective tissue disorder

INTRODUCTION

Unilateral lambdoidal craniosynostosis is a rare disorder that occurs in approximately 3 % of all craniosynostosis phenotypes and only 0.03 % of one million live births. It is even more unusual for this type of synostosis to occur in siblings with only two other cases reported in the literature.

CASE REPORT

We report a set of full-term dizygotic twins born with lambdoidal synostosis and a family history of connective tissue and cardiovascular anomalies. One of the twins also had concomitant bicoronal craniosynostosis.

CONCLUSION

True familial lambdoidal synostosis is exceedingly rare. The present cases in dizygotic twins occurred in a family with a significant history of connective tissue disease suggesting a possible association.

Prevention and management of positional skull deformities in infants

Positional skull deformities may be present at birth or may develop during the first few months of life. Since the early 1990s, US pediatricians have seen an increase in the number of children with cranial asymmetry, particularly unilateral flattening of the occiput, likely attributable to parents following the American Academy of Pediatrics "Back to Sleep" positioning recommendations aimed at decreasing the risk of sudden infant death syndrome. Positional skull deformities are generally benign, reversible head-shape anomalies that do not require surgical intervention, as opposed to craniosynostosis, which can result in neurologic damage and progressive craniofacial distortion. Although associated with some risk of positional skull deformity, healthy young infants should be placed down for sleep on their backs. The practice of putting infants to sleep on their backs has been associated with a drastic decrease in the incidence of sudden infant death syndrome. Pediatricians need to be able to properly differentiate infants with benign skull deformities from those with craniosynostosis, educate parents on methods of proactively decreasing the likelihood of the development of occipital flattening, initiate appropriate management, and make referrals when necessary. This report provides guidance for the prevention, diagnosis, and management of positional skull deformity in an otherwise normal infant without evidence of associated anomalies, syndromes, or spinal disease.

Analysis of differences in the cranial base and facial skeleton of patients with lambdoid synostosis and deformational plagiocephaly

BACKGROUND

Earlier investigations suggest that the morphologic features of patients with lambdoid synostosis include ipsilateral occipital flattening, an ipsilateral mastoid prominence, downward cant of the posterior skull base to the affected side, and contralateral hemifacial deficiency. These features are absent in patients with deformational plagiocephaly. The authors hypothesize that significant differences in craniofacial morphology exist between patients with lambdoid synostosis and those with deformational plagiocephaly.

METHODS

Craniometric measurements were performed on patients with unilateral lambdoid synostosis (n = 9) and deformational plagiocephaly (n = 12). Measurements were performed on affected and unaffected sides and included posterior fossa deflection angle, petrous ridge angle, middle cranial fossa and anterior cranial fossa area, temporomandibular joint displacement, and maxillary and mandibular dimensions. Appropriate statistical tests were performed.

RESULTS

Statistically significant differences in posterior fossa deflection angle, petrous ridge angle, and middle cranial fossa were found between groups. Lambdoid synostosis patients demonstrated a larger petrous ridge angle (p = 0.0001) and middle cranial fossa (p = 3.37 × 10(-6)) on the unaffected side. Deformational plagiocephaly patients exhibited no discrepancies between sides. The mean posterior fossa deflection angle was 10.55 degrees for the lambdoid synostosis group and 3.59 degrees for the deformational plagiocephaly group (p < 0.0001). All lambdoid synostosis patients had deviation of the posterior cranial fossa toward the affected side. Deformational plagiocephaly patients had variable deflection. All lambdoid synostosis patients demonstrated marked posterior displacement of the contralateral temporomandibular joint. Deformational plagiocephaly patients had either symmetric temporomandibular joint position (75 percent) or slight contralateral posterior displacement (25 percent). Mandibular size was not significantly different between groups.

CONCLUSION

Patients with lambdoid synostosis and deformational plagiocephaly manifest significant differences in cranial base morphology, contributing to the phenotypic differences seen in these two groups of patients.

A 150-year conundrum: cranial robusticity and its bearing on the origin of aboriginal australians

The origin of Aboriginal Australians has been a central question of palaeoanthropology since its inception during the 19th Century. Moreover, the idea that Australians could trace their ancestry to a non-modern Pleistocene population such as Homo erectus in Southeast Asia have existed for more than 100 years, being explicitly linked to cranial robusticity. It is argued here that in order to resolve this issue a new program of research should be embraced, one aiming to test the full range of alternative explanations for robust morphology. Recent developments in the morphological sciences, especially relating to the ontogeny of the cranium indicate that character atomisation, an approach underpinning phylogenetic reconstruction, is fraught with difficulties. This leads to the conclusion that phylogenetic-based explanations for robusticity should be reconsidered and a more parsimonious approach to explaining Aboriginal Australian origins taken. One that takes proper account of the complex processes involved in the growth of the human cranium rather than just assuming natural selection to explain every subtle variation seen in past populations. In doing so, the null hypothesis that robusticity might result from phenotypic plasticity alone cannot be rejected, a position at odds with both reticulate and deep-time continuity models of Australian origins.

Holoprosencephaly and craniosynostosis: A report of two siblings and review of the literature

Holoprosencephaly (HPE) and craniosynostosis are separate conditions that have occasionally been observed to occur simultaneously in the same patient. Here, we compile patients with both conditions who have been documented in the literature thus far; moreover, we report on two additional siblings who have not been previously described. We also compare the clinical features of these patients and discuss the previously hypothesized possibility of an independent association including both HPE and craniosynostosis.

Synchrotron-microcomputed tomography studies of normal and pathological cranial sutures: further insight

OBJECT

Both CT and high-frequency ultrasound have been shown to be reliable diagnostic tools used to differentiate normal cranial sutures from suture synostosis. In nonsynostotic plagiocephaly, overlapping of the bony plates and the so-called "sticky suture" is still controversial and is believed to represent a pathological fusion process. Synchrotron-microcomputed tomography (SRmCT) studies were undertaken to determine whether positional head deformities can be assumed to be true suture pathologies.

METHODS

Morphological features and growth development of 6 normal cranial sutures between the ages of 3 and 12 months were analyzed histologically. Additionally 6 pathological sutures, including sagittal synostosis and nonsynostotic plagiocephaly (NSP), were compared with the group of normal sutures by histological and SRmCT studies. Synchrotron-microcomputed tomography is a special synchrotron radiation source with a high photon flux providing a monochromatic x-ray beam with a very high spatial resolution. Morphological characteristics of the different suture types were evaluated and bone density alongside the sutures was measured to compare the osseous structure of the adjacent bony plates of normal and pathological sutures.

RESULTS

Histologically jointlike osseous edges of the normal sutures were seen in the 1st month of life and interlocking at the age of approximately 12 months. During this 1st year, bone thickness increases and suture width decreases. The SRmCT studies showed that: 1) sutures and adjacent bones in NSP are comparable to normal sutures in terms of their morphological aspects; 2) bone densities in the adjacent bony plates of NSP and normal sutures are not different; 3) thickening of the diploe with ridging of the bone in sagittal synostosis is associated with significantly higher bone density; 4) synostotic sutures are only partially fused but vary in their extent; and 5) nonfused sections in sagittal synostosis behave like normal sutures without any signs of pathological bone formation.

CONCLUSIONS

Sutures in patients with NSP were found without any morphological irregularities or different osseous structures alongside those compared with normal sutures. Thus, a true suture pathology or osseous change of the adjacent bony plates is highly unlikely in NSP. Even though the number of specimens is limited in this series, cranial suture fusion seems to start at one undetermined point and spread along the suture, whereas other parts of the same suture are not involved according to morphological aspects and bone density measurements of the adjacent bones. This theory may represent a dynamic fusion process completed over time but just starting too early.

Characteristics, head shape measurements and developmental delay in 287 consecutive infants attending a plagiocephaly clinic

AIM

To describe the characteristics, developmental status and severity of head shape deformation in infants presenting to a plagiocephaly clinic.

METHODS

Head shape was measured and neck function assessed in 287 consecutive infants presenting to a plagiocephaly outpatient clinic. Information was obtained on demographic and obstetric factors, plagiocephaly history and current positioning strategies. Development was assessed by the Ages and Stages Questionnaire (ASQ).

RESULTS

After clinical examination, craniosynostosis was suspected in seven infants (2%) and a skull computed tomography (CT) scan was performed; five showed suture abnormalities. Fifty-eight percent of cases had a history of limitation of neck function; this was more likely in plagiocephalic infants than brachycephalic infants. Males, firstborn infants, instrument-delivered infants, supine sleep position and right-sided flattening were predominant. One or more delays on the ASQ were seen in 36% of infants.

CONCLUSION

Physical examination of infants with head shape deformities is essential in order to rule out craniosynostosis. Infants with deformational plagiocephaly frequently have neck muscle dysfunction. We postulate that the higher than expected number of developmental delays may be related to the effects of supine sleep position, low or variable tone, lower activity levels, male gender and neck muscle dysfunction.

Symptomatic asymmetry in the first six months of life: differential diagnosis

Asymmetry in infancy is a clinical condition with a wide variation in appearances (shape, posture, and movement), etiology, localization, and severity. The prevalence of an asymmetric positional preference is 12% of all newborns during the first six months of life. The asymmetry is either idiopathic or symptomatic. Pediatricians and physiotherapists have to distinguish symptomatic asymmetry (SA) from idiopathic asymmetry (IA) when examining young infants with a positional preference to determine the prognosis and the intervention strategy. The majority of cases will be idiopathic, but the initial presentation of a positional preference might be a symptom of a more serious underlying disorder. The purpose of this review is to synthesize the current information on the incidence of SA, as well as the possible causes and the accompanying signs that differentiate SA from IA. This review presents an overview of the nine most prevalent disorders in infants in their first six months of life leading to SA. We have discovered that the literature does not provide a comprehensive analysis of the incidence, characteristics, signs, and symptoms of SA. Knowledge of the presented clues is important in the clinical decision making with regard to young infants with asymmetry. We recommend to design a valid and useful screening instrument.

A population-based study of craniosynostosis in metropolitan Atlanta, 1989-2003

Craniosynostosis is a birth defect characterized by premature fusion of one or more cranial sutures. We describe the birth prevalence of craniosynostosis and related risk factors among infants born to residents of metropolitan Atlanta during 1989-2003. Data from the Metropolitan Atlanta Congenital Defects Program (MACDP) were used to identify infants with craniosynostosis. Case records with a code for craniosynostosis were reviewed to substantiate the diagnosis of craniosynostosis and to classify infants as having isolated craniosynostosis (no other unrelated major defects), multiple defects (one or more additional major, unrelated defects), or a syndrome (recognized or strongly suspected single-gene condition or chromosome abnormality). Vital records data on births of Georgia residents were used to analyze craniosynostosis prevalence by year of birth, maternal race and age, parity, plurality, and infants' sex, birth weight, and gestational age. We identified 281 infants born with craniosynostosis in metropolitan Atlanta during 1989-2003: 84% with isolated craniosynostosis, 7% with multiple defects, and 9% with syndromes. The birth prevalence was 4.3 per 10,000 births, results consistent with findings from other population-based studies using similar case definitions. Apert syndrome was diagnosed in 40% of the syndromic cases, and sagittal synostosis was diagnosed in 39% of the cases of nonsyndromic craniosynostosis. Maternal age 35 years or older, multiple birth, male sex, and birth weight >4,000 g were risk factors for craniosynostosis.

The misdiagnosis of craniosynostosis as deformational plagiocephaly

Deformational plagiocephaly, unilateral coronal craniosynostosis, and lambdoid craniosynostosis all cause oblique deformities of the skull. They are separate entities with different etiologies resulting in clear differences of physical examination, radiologic findings, and clinical course. Treatment for each condition is markedly different. Surgical intervention is recommended for unilateral coronal and lambdoid craniosynostosis using different techniques. Deformational plagiocephaly, on the other hand, is often satisfactorily managed with conservative treatment. We present 4 clinical reports on patients in whom unilateral coronal craniosynostosis and lambdoid craniosynostosis were originally misdiagnosed as occipital deformational plagiocephaly and highlight individual structural distinctions.

Evaluation of the infant with an abnormal skull shape

PURPOSE OF REVIEW

Atypical skull shapes occur in as many as 20% of infants. The purpose of this review is to discuss the clinical approach to the evaluation of a child with an abnormal head shape. Readers will learn how to identify the head shapes caused by environmental deformation and craniosynostosis. We also review recent findings with regard to the genetics of single-suture craniosynostosis.

RECENT FINDINGS

Healthcare providers can use key aspects of the examination of a child with a head shape abnormality to differentiate positional deformity from craniosynostosis. Overlap between the genetic causes of isolated single-suture craniosynostosis and syndromic forms is discussed.

SUMMARY

Pediatricians can identify the causes of the majority of head shape abnormalities by combining their understanding of normal calvarial growth with a careful physical examination. Molecular genetics is playing an increasing role in the evaluation of children with single-suture fusion.

True Lambdoid Craniosynostosis: Long-Term Results of Surgical and Conservative Therapy

BACKGROUND

True lambdoid synostosis is a rare malformation. Few clinical reports have examined the efficacy of conservative or surgical management in the care of these patients.

METHODS

All patients with a diagnosis of true lambdoid synostosis treated by the senior author (S.P.B.) at The Children's Hospital of Philadelphia between 1990 and 2005 were included in the study. Both qualitative and quantitative assessments of craniofacial growth were performed following either conservative or surgical management. Qualitative assessments were made based on preoperative and postoperative photographs, computed tomographic scans, and a review of patient charts. A quantitative assessment of ear position was performed using craniometric analysis and the appropriate statistical tests.

RESULTS

The study included nine patients--six who underwent surgical intervention and three who did not undergo transcranial surgery to date. The authors' analysis of patient data revealed a predictable craniofacial dysmorphism manifest as occipital flattening, an ipsilateral occipitomastoid bulge, and a pronounced hemifacial deficiency. Generally, these malformations improved following operative management. A quantitative analysis of preoperative and postoperative ear position displayed no statistically significant vertical or anteroposterior displacement. In one untreated patient, true lambdoid synostosis resulted in persistent severe asymmetry of the cranial vault and facial skeleton.

CONCLUSIONS

True lambdoid synostosis, if left untreated, results in pronounced craniofacial asymmetry. Although a diversity of clinical presentations exists, diagnostic features include occipital flattening, an ipsilateral occipitomastoid bulge, and a contralateral hemifacial deficiency. Posterior vault switch cranioplasty is an effective treatment for true lambdoid synostosis when performed in the first year of life.

Deformational plagiocephaly associated with ocular torticollis: a clinical study and literature review

The etiology of craniofacial asymmetry secondary to positional plagiocephaly with or without concomitant congenital muscular torticollis has been well established. It has been proposed that the craniofacial asymmetry secondary to congenital superior oblique palsy involves a similar etiology. The causal relationship has been thought to be a result of the adoption of certain head and neck positioning, which predisposes the infant to develop preferential resting positions during supine sleep. We present a single subject with ocular torticollis and resulting plagiocephaly, and we distinguish the resultant craniofacial findings from those seen in patients with congenital muscular torticollis-associated deformational plagiocephaly. The distinctions that exist between the resultant asymmetries observed in ocular torticollis with superior oblique palsy and those found with congenital muscular torticollis suggest that the facial hemihypoplasia observed in conjunction with ocular torticollis may be the result of gravitational forces rather than compressive forces.

Displacement of brain regions in preterm infants with non-synostotic dolichocephaly investigated by MRI

Regional investigations of newborn MRI are important to understand the appearance and consequences of early brain injury. Previously, regionalization in neonates has been achieved with a Talairach parcellation, using internal landmarks of the brain. Non-synostotic dolichocephaly defines a bi-temporal narrowing of the preterm infant's head caused by pressure on the immature skull. The impact of dolichocephaly on brain shape and regional brain shift, which may compromise the validity of the parcellation scheme, has not yet been investigated. Twenty-four preterm and 20 fullterm infants were scanned at term equivalent. Skull shapes were investigated by cephalometric measurements and population registration. Brain tissue volumes were calculated to rule out brain injury underlying skull shape differences. The position of Talairach landmarks was evaluated. Cortical structures were segmented to determine a positional shift between both groups. The preterm group displayed dolichocephalic head shapes and had similar brain volumes compared to the mesocephalic fullterm group. In preterm infants, Talairach landmarks were consistently positioned relative to each other and to the skull base, but were displaced with regard to the calvarium. The frontal and superior region was enlarged; central and temporal gyri and sulci were shifted comparing preterm and fullterm infants. We found that, in healthy preterm infants, dolichocephaly led to a shift of cortical structures, but did not influence deep brain structures. We concluded that the validity of a Talairach parcellation scheme is compromised and may lead to a miscalculation of regional brain volumes and inconsistent parcel contents when comparing infant populations with divergent head shapes.

Regional brain development in serial magnetic resonance imaging of low-risk preterm infants

OBJECTIVE

MRI studies have shown that preterm infants with brain injury have altered brain tissue volumes. Investigation of preterm infants without brain injury offers the opportunity to define the influence of early birth on brain development and provide normative data to assess effects of adverse conditions on the preterm brain. In this study, we investigated serial MRI of low-risk preterm infants with the aim to identify regions of altered brain development.

METHODS

Twenty-three preterm infants appropriate for gestational age without magnetic resonance-visible brain injury underwent MRI twice at 32 and at 42 weeks' postmenstrual age. Fifteen term infants were scanned 2 weeks after birth. Brain tissue classification and parcellation were conducted to allow comparison of regional brain tissue volumes. Longitudinal brain growth was assessed from preterm infants' serial scans.

RESULTS

At 42 weeks' postmenstrual age, gray matter volumes were not different between preterm and term infants. Myelinated white matter was decreased, as were unmyelinated white matter volumes in the region including the central gyri. The gray matter proportion of the brain parenchyma constituted 30% and 37% at 32 and 42 weeks' postmenstrual age, respectively.

CONCLUSIONS

This MRI study of preterm infants appropriate for gestational age and without brain injury establishes the influence of early birth on brain development. No decreased cortical gray matter volumes were found, which is in contrast to findings in preterm infants with brain injury. Moderately decreased white matter volumes suggest an adverse influence of early birth on white matter development. We identified a sharp increase in cortical gray matter volume in preterm infants' serial data, which may correspond to a critical period for cortical development.

Neurodevelopmental Delays in Children with Deformational Plagiocephaly

BACKGROUND

The purpose of this study was to determine whether, in fact, infants with deformational plagiocephaly, or plagiocephaly without synostosis, demonstrated cognitive and psychomotor developmental delays when compared with a standardized population. Through this study, we chose to expand upon our earlier findings from 2001 on patients with deformational plagiocephaly.

METHODS

The study population includes a total of 110 consecutive patients, prospectively followed then retrospectively reviewed. Each infant was assessed using the Bayley Scales of Infant Development-II scoring system. The developmental analysis was categorized as either mental or psychomotor using the mental developmental index or the psychomotor developmental index, respectively. These infants were subcategorized into four groups: accelerated, normal, mild, or severely delayed. The groups were then compared with a standardized Bayley's age-matched population, using chi-square test goodness-of-fit tests.

RESULTS

Infants with deformational plagiocephaly were found to have significantly different psychomotor development indexes and mental developmental indexes when compared with the standardized population (p < 0.0001; p < 0.0001). With regards to the mental developmental index scores, none of the infants with deformational plagiocephaly were accelerated, 90 percent were normal, 7 percent were mildly delayed, and 3 percent were severely delayed. With regards to the psychomotor development index scores, none of infants were accelerated, 74 percent were normal, 19 percent were mildly delayed, and 7 percent were severely delayed.

CONCLUSIONS

This study indicates that before any intervention, infants with deformational plagiocephaly show significant delays in both mental and psychomotor development. Also of particular note is that no child with deformational plagiocephaly showed accelerated development.

Impacting infant head shapes

Infant sleep position impacts the development of head shape. Changes in infant sleep position, specifically the movement toward supine sleep, have led to a redefinition of normal head shape for infants in the United States. Historically, a dolichocephalic (elongated) head shape was the norm. Currently the norm has changed to a more brachycephalic (shorter and broader) shape. Since the American Academy of Pediatrics' Back to Sleep Campaign, the incidence of positional plagiocephaly has increased dramatically with a concurrent rise in the incidence of torticollis. Infants who require newborn intensive care, particularly premature infants, are more prone to positional plagiocephaly and dolichocephaly. Both can be prevented or minimized by proper positioning. The infant with an abnormal head shape requires careful evaluation; treatment varies according to the etiology. Craniosynostosis, a less common but pathological etiology for plagiocephaly, should be considered in the diagnostic process. Successful treatment of positional plagiocephaly and dolichocephaly includes systematic positioning changes to overcome the mechanical forces of repetitive positioning, physical and/or occupational therapy to treat underlying muscle or developmental challenges, and in some cases, molding helmet therapy.

Concordant contralateral lambdoidal synostosis in dizygotic twins

Twin studies have been widely used to investigate genetic versus environmental causality of malformations. While there are numerous reports of concordant sutural fusions in syndromic twins, there are few cases in siblings with nonsyndromic single suture synostosis. Lambdoidal synostosis has no clear genetic etiology. Discordant synostosis has been reported in one monozygotic twin; there is also an unsubstantiated report of concordance in dizygotic twins. We describe dizygotic twins concordant for contralateral lambdoidal synostosis. Mutational analysis for FGFR 1,2,3 was negative. Given the low incidence, absence of reported inheritability, and lack of documented concordance in monozygotic twins, the pathogenesis of isolated lambdoidal fusion can only be ascribed to stochastic influences.

Malformations of the axial skeleton in the museum Vrolik: II: craniosynostoses and suture-related conditions

The Museum Vrolik collection of anatomical specimens in Amsterdam, The Netherlands, comprises over 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, we rediagnosed a subset of the collection comprising dried infantile, juvenile, and adult human skulls with congenital and acquired conditions. On external examination and additional radiography, we found 58 skulls with craniosynostosis (CS) involving one or more sutures and 40 skulls with a presumed suture related condition. Most of these were part of the material collected and described by Louis Bolk (1866-1930). Analysis of his observations suggests that skull deformation because of premature suture closure depends not only on the identity of the sutures involved but also on the timing and progression of their closure and the extent of their involvement. Moreover, premature closure of the sagittal suture after 3-6 years of age appeared to be much more common than expected because it is not accompanied by skull deformation. Many of the skulls with single-suture CS were microcephalic, which may be the cause of the premature synostosis. By contrast, microcephaly may be a resulting phenomenon in multi-suture CS. We noticed that the quotient between height of the cranial vault (vertex-porion distance) and head circumference, multiplied by 100, was 26 or higher only in those CS cases with multi-suture involvement. We therefore consider this parameter, which we named "acrocephalic index", to be an indicator of multi-suture involvement in individual CS cases. In two adult skulls, the skull had a quadrangular shape, which we assumed to be correlated to the presence of an unusually interdigitated open metopic suture. We propose to name this anomaly: tetragonocephaly. Another presumed suture-related condition, bathrocephaly, was found concomitantly with basilar invagination in several cases. We hypothesize that the chronically raised intracranial pressure in these cases caused the still open lambdoidal sutures to distend and the occipital bone to protrude.

Three-dimensional analysis of morphological changes in the maxilla of patients with cleft lip and palate

OBJECTIVE

Three-dimensional (3-D) morphological changes in the maxilla of patients with cleft lip and palate (CLP) have been recorded, mainly using two-dimensional cast analyses. Although these seem to be insufficient, no standardized 3-D method has been developed until now. In this study, accuracy, precision, and validity of a newly developed 3-D digital computer-aided procedure to visualize and metrically analyze the growth of the edentulous maxilla of infants with CLP have been evaluated.

PATIENTS

The method was applied to 10 infants with complete unilateral CLP.

INTERVENTIONS

Consecutive casts of the maxilla (1 week and 3, 6, and 12 months) of each patient were optically measured with a 3-D laser scanner. Following digitizing, the casts were computer reconstructed, aligned, and superimposed using specialized computer software. The distances between the surfaces were measured. Additionally, the surfaces were segmented perpendicular to the alveolar crest, the reference points being C1, C1', C2, C2', and I. The volumes of the resulting segments were determined and compared with one another.

RESULTS

The newly developed analysis enables a visualization of the extent and direction of morphological changes in the maxilla of infants with CLP. With this method it is possible to quantify these changes of the volume of defined alveolar segments.

CONCLUSIONS

The 3-D analysis developed is an ideal tool for the examination of 3-D morphological changes in the edentulous maxilla of patients with CLP. The results will serve as the starting point for a longitudinal study on the efficacy of different methods, not only of presurgical infant orthopedics but also of surgical procedures.

Craniofacial Growth in Unoperated Craniofacial Malformations

Objective and Purpose

To review current information on craniofacial growth of unoperated patients with craniofacial malformations and stimulate the study of abnormal craniofacial growth through conventional and newer methods. This will lead to improved diagnosis and the understanding of the etiopathogenesis of craniofacial malformations. It is expected that this knowledge will also assist clinicians in planning treatment strategies to better manage these challenging conditions.

State of the art in craniofacial surgery: nonsyndromic craniosynostosis

Craniosynostosis refers to the premature fusion of one of the six major sutures of the cranial vault. Functionally, craniosynostosis may be defined as the premature conversion of the dynamic region of growth and resorption between two adjacent bones of the cranium into a static region of bony union. Molecular analysis has blurred the traditional categories of nonsyndromic and syndromic synostosis to some extent, but, in general, the distinctions between the two groups still hold true. The complexity of the congenital anomalies may be limited with the former, whereas the latter usually requires reoperations and correction of the facial skeleton. This article briefly outlines the characteristic deformities produced from nonsyndromic craniosynostosis. Various approaches to surgical correction of the deformities are described. Finally, new biomaterials that are used in the correction of nonsyndromic craniosynostosis are reviewed.