Ultrasound diagnosis of craniosynostosis

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.

Characterization of Perinatal Risk Factors and Complications Associated With Nonsyndromic Craniosynostosis

BACKGROUND

Certain intrauterine risk factors are known to increase the risk of premature cranial suture fusion and may cause complications during birth. Some of these risk factors may be modifiable. Therefore, the authors sought to characterize the institutional patterns of prenatal risk factors and perinatal complications in nonsyndromic craniosynostosis patients compared to normal births from the surrounding area to identify areas for possible intervention or prevention.

METHODS

The medical records of all infants with nonsyndromic craniosynostosis and full birth records born at Duke University Health System from 2006 to 2017 were retrospectively reviewed. Maternal comorbidities, prenatal risk factors, and perinatal complications were collected. The North Carolina State Center for Health Statistics was queried for perinatal statistics from Durham county and the Northeastern Perinatal Care Region to represent a control cohort of normal births from the same time period and region. The primary outcome investigated was the incidence of prenatal risk factors and complications at birth associated with premature fusion of cranial sutures.

RESULTS

Eighty births with nonsyndromic craniosynostosis were included in this study. The majority of these patients were males (61.7%) and born via cesarean section (55.0%). Intrauterine growth restriction occurred in 10.0% and head trauma during delivery occurred in 2.5%. Twinning (14.8% vs 3.6%, P < 0.0001), cesarean births (55.5% vs 30.0%, P < 0.0001), and breech presentation (17.3% vs 3.2%, P < 0.0001) were significantly more common in craniosynostosis patients. Prenatally, mothers of craniosynostosis infants had higher incidence of gestational diabetes (13.5% vs 5.0%, P < 0.0001) and oligohydramnios (6.1% vs 1.3%, P < 0.0001) compared to regional controls.

CONCLUSION

This study demonstrates that premature suture fusion is associated with prenatal risk factors such as gestational diabetes and oligohydramnios. Continued research into potentially modifiable prenatal risk factors and more refined prenatal diagnostic tools has the potential to reduce both the incidence of premature suture fusion and the sequelae of birth complications in this population.

Quantification of Head Shape and Cranioplasty Outcomes: Six-compartment Volume Method Applied to Sagittal Synostosis

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Background:

Premature fusion of the sagittal (midline) suture between 2 parietal bones is the most common form of craniosynostosis. Surgical correction is mandated to improve head shape and to decrease the risk of raised intracranial pressure. This study evaluated the utility of 3-dimensional (3D) imaging to quantify the volumetric changes of surgical correction. Currently there is no standardized method used to quantify the outcomes of surgery for craniosynostosis, with the cranial index (width: length ratio) being commonly used.

Methods:

A method for quantification of head shape using 3D imaging is described in which the cranium is divided up into 6 compartments and the volumes of 6 compartments are quantified and analyzed. The method is size invariant, meaning that it can be used to assess the long-term postoperative outcomes of patients through growth. The method is applied to a cohort of sagittal synostosis patients and a normal cohort, and is used to follow up a smaller group of synostotic patients 1, 2, and 3 years postoperatively.

Results:

Statistical analysis of the results shows that the 6-compartment volume quantification method is more accurate in separating normal from synostotic patient head shapes than the cranial index.

Conclusions:

Spring-mediated cranioplasty does not return head shape back to normal, but results in significant improvements in the first year following surgery compared with the preoperative sagittal synostosis head shape. 3D imaging can be a valuable tool in assessing the volumetric changes due to surgery and growth in craniosynstosis patients.

Prenatal ultrasonography of craniofacial abnormalities

Craniofacial abnormalities are common. It is important to examine the fetal face and skull Epub ahead of print during prenatal ultrasound examinations because abnormalities of these structures may indicate the presence of other, more subtle anomalies, syndromes, chromosomal abnormalities, or even rarer conditions, such as infections or metabolic disorders. The prenatal diagnosis of craniofacial abnormalities remains difficult, especially in the first trimester. A systematic approach to the fetal skull and face can increase the detection rate. When an abnormality is found, it is important to perform a detailed scan to determine its severity and search for additional abnormalities. The use of 3-/4-dimensional ultrasound may be useful in the assessment of cleft palate and craniosynostosis. Fetal magnetic resonance imaging can facilitate the evaluation of the palate, micrognathia, cranial sutures, brain, and other fetal structures. Invasive prenatal diagnostic techniques are indicated to exclude chromosomal abnormalities. Molecular analysis for some syndromes is feasible if the family history is suggestive.

Craniosynostosis - Recognition, clinical characteristics, and treatment

Craniosynostosis is a developmental craniofacial anomaly, resulting in impairment of brain development and abnormally shaped skull. The main cause of craniosynostosis is premature closure of one or more cranial sutures. It usually occurs as an isolated condition, but may also be associated with other malformations as part of complex syndromes. When left untreated, craniosynostosis can cause serious complications, such as developmental delay, facial abnormality, sensory, respiratory and neurological dysfunction, anomalies affecting the eye, and psychological disturbances. Thus, early diagnosis, expert surgical techniques, postoperative care, and adequate follow-up are of vital importance in treating craniosynostosis.

Quantitative analysis of ultrasound images for computer-aided diagnosis

We propose an adaptable framework for analyzing ultrasound (US) images quantitatively to provide computer-aided diagnosis using machine learning. Our preliminary clinical targets are hepatic steatosis, adenomyosis, and craniosynostosis. For steatosis and adenomyosis, we collected US studies from 288 and 88 patients, respectively, as well as their biopsy or magnetic resonanceconfirmed diagnosis. Radiologists identified a region of interest (ROI) on each image. We filtered the US images for various texture responses and use the pixel intensity distribution within each ROI as feature parameterizations. Our craniosynostosis dataset consisted of 22 CT-confirmed cases and 22 age-matched controls. One physician manually measured the vectors from the center of the skull to the outer cortex at every 10 deg for each image and we used the principal directions as shape features for parameterization. These parameters and the known diagnosis were used to train classifiers. Testing with cross-validation, we obtained 72.74% accuracy and 0.71 area under receiver operating characteristics curve for steatosis ([Formula: see text]), 77.27% and 0.77 for adenomyosis ([Formula: see text]), and 88.63% and 0.89 for craniosynostosis ([Formula: see text]). Our framework is able to detect a variety of diseases with high accuracy. We hope to include it as a routinely available support system in the clinic.

Recommendations on routine mid-trimester anomaly scan

The purpose of this paper is to discuss the minimal requirements of the routine mid-trimester anomaly scan in Asian countries after taking into account various factors, including local circumstances, medical practice, guidelines, and availability of experienced sonographers and high-resolution ultrasound machines, which affect the prenatal detection rate of fetal anomalies. In general, a routine mid-trimester anomaly scan includes the assessment of the number of fetuses, fetal cardiac activity, size, anatomy, liquor and placental location. The most controversial issue is which fetal structures should at least be examined. We discussed the requirements of a basic routine scan, as well as the optional views, which can be obtained if feasible to improve the detection of fetal, placental or maternal abnormalities. Routine anomaly scan remains a clinical challenge.

Anterior plagiocephaly: epidemiology, clinical findings,diagnosis, and classification. A review

INTRODUCTION

Anterior plagiocephaly due to the early unilateral fusion of the coronal suture is associated to a clinical phenotype characterized by the unilateral flattening of the frontal bone and the orbit and by the distortion and maldevelopment of adjacent cranial and facial bones. Homolateral anterior displacement of the ear and contralateral deviation of the nasal pyramid and mandible are other prominent clinical features. The differential diagnosis includes a variety of conditions characterized by facial asymmetry, namely, due to muscular alterations, anomalies of the visual function, congenital anomalies of the cervical spine and craniovertebral junction, abnormal pregnancy, and birth injuries. Anterior plagiocephaly is the direct cause of oculomotor anomalies, with a characteristic strabismus, and of progressive asymmetrical maldevelopment of the face, craniovertebral junction, and cervical spine.

METHODS

The medical literature was reviewed in regard to the epidemiology, clinical features, and radiological findings. Different categorization of the affected infants in specific subtypes according to the severity of the condition was analyzed. The aim was to contribute to a practical clinical classification to be utilized for the surgical indication and for predicting the prognosis according to the severity of the condition at presentation.

CONCLUSIONS

Anterior plagiocephaly represents the most challenging simple suture craniosynostosis. The clinical differential diagnosis with other forms of cranial asymmetry is possible on the grounds of mere clinical findings. A classification system is necessary not only for the establishment of surgical planning but also to predict the late cosmetic and functional outcomes.

Acrocephalosyndactyly, Apert type, in a newborn: Cerebral sonography

We describe the clinical and cerebral ultrasonographic features of a rare case of type 1 acrocephalosyndactyly (Apert syndrome). The patient was a newborn male whose twin had died in utero. Most cases of Apert syndrome are sporadic, although autosomal dominant inheritance has also been reported. Diagnosis is based on physical examination together with imaging data. Since Apert syndrome can give rise to numerous CNS abnormalities, affected newborns should undergo echoencephalography for more complete characterization of their malformations.

Diagnostic imaging in the management of craniosynostoses

Craniosynostoses are the most frequent craniofacial malformations. However, with a prevalence of 3-6 cases per 10,000 live births they are amongst the rarely seen diseases and their definite diagnosis thus poses a challenge to the physician. When an abnormal calvarial configuration is detected, a radiological evaluation is necessary to characterize the deformity and to guide the corrective surgical procedure. The demand for clear diagnostic criteria is justified by the severity of the disease and the possible consequences of delayed diagnosis. In addition to the clinical signs (deformation of the head), conventional skull X-rays show typical radiological alterations and are used for basic diagnostics. Diagnostic tests that may be performed to confirm the diagnosis and assess the extent of the problem, include computed tomography (CT), 3D-CT, magnetic resonance imaging (MRI) scans, and ultrasonography. In the present review we will describe the most important clinical and radiological characteristics of craniosynostosis by means of clinical, radiological and operative situs examples.

Ultrasound in the Diagnosis of Craniosynostosis

Diagnosis of craniosynostosis is based on clinical aspects but may be difficult in some cases where characteristic features are missing and radiographic imaging is necessary. In this context near-field high-frequency ultrasound has been used to evaluate the sonographic characteristics of synostotic sutures and its potential confirming the correct diagnosis. Sutures of 26 infants, aged 2-7 months, were investigated by ultrasound (Siemens Elegra, 7.5 MHz linear scanner). Sonographic features of synostotic sutures were correlated to CT imaging and compared to the sonographic and histopathological findings of normal cranial sutures. Hyperechogenic bridging of sutures with or without ridging were the characteristic aspects of synostotic sutures. All 26 patients could be reliable diagnosed showing partial (n = 21) or total fusion (n = 5) of one or more sutures consisting with craniosynostosis. Length of synostosis was identified exactly by sonography and imaging found to enable a classification of ultrastructural details of bony and soft tissue next to the synostotic suture. Ultrasound is a less expensive, nonradiating and easy-to-handle tool ensuring the diagnosis of craniosynostosis. Sonography offers the potential to be a standard investigation for infants with head deformities suspecting a suture pathology and has been therefore integrated in our craniofacial outpatient clinic as a daily routine method.

Pitfalls for the pediatrician: positional molding or craniosynostosis?

Abnormal head morphology is common among infants and often leads parents to ask their pediatricians for guidance. While the vast majority of such children development and prevent adverse neurobehavioral sequelae secondary to increased intracranial pressure or impaired cerebral growth. The coordination of a multidisciplinary team in the setting of a center experienced in the management of craniosynostosis will assure the best possible results for each patient.

Anthropometric proportion indices in the craniofacial regions of 73 patients with forms of isolated coronal synostosis

The study group consisted of 73 North American patients (29 males and 44 females), aged between 0-5 months and 20 years, 26 with right, 33 with left, and 14 with bicoronal synostosis. Basic proportion indices were established in 5 craniofacial regions (cranial, facial, orbital, nasal, oral) calculated from 2 projective measurements [cranial: eu-eu, g-op; facial: n-gn, zy-zy; orbital: en-en, ex-ex; nasal: al-al, n-sn; oral: sn-sto, ch-ch (eu, eurion; g, glabella; op, opisthocranion; n, nasion; gn, gnathion; zy, zygion; en, endocanthion; ex, exocanthion; al, alare; sn, subnasale; sto, stomion; ch, chelion)] taken from the patients by the first author before surgery. These data were then compared with the anthropometric norms established for North American whites (Farkas LG. Anthropometry of the Head and Face. 2nd ed. Raven Press; 1994). In males, the total percentage of normal, subnormal, and supernormal proportion indices was smaller than in females in all 3 groups of patients. Generally, the difference in percentage between normal proportions was the smallest (13.1%) and the supernormal one the greatest (68%). In males, the oral measurements showed the highest frequency of normal proportions (100%) in all 3 patient groups, and the cephalic index the lowest (60%-66.7%). Among the abnormal proportions, the supernormal ones were found more often, especially in the cranial region of females with bilateral coronal synostosis (66.7%). Subnormal proportion indices were rare: none were seen in the facial region of males. A subnormal cephalic index (eu-eu/g-op) was not present in either sex in right and bicoronal synostosis and was observed in only 2 males with left coronal synostosis (13.3%). The study showed that the influence of synostosis gradually decreased from the top to the bottom of the face, with the oral region showing no abnormalities.

Usefulness of Magnetic Resonance Imaging for Accurate Diagnosis of Pfeiffer Syndrome Type II in utero

OBJECTIVE

To present the usefulness of fetal magnetic resonance (MR) imaging for accurate diagnosis of Pfeiffer syndrome type II.

CASE AND METHODS

A 19-year-old woman was referred to us at 29 weeks of gestation for prenatal management of hydrocephalus. Ultrasonography of the fetus showed cloverleaf skull with dilated lateral ventricles, exophthalmos, macroglossia, and a single ventricle of the heart in addition to polyhydramnios. MR imaging was performed at 30 weeks of gestation and revealed cloverleaf skull, dilated lateral ventricles, and broad thumb. Fetal karyotyping indicated 46,XY, but DNA sequence analysis showed a single sequence variation (Nt 1198A>G) in the fibroblast growth factor receptor (FGFR) 2 gene (exon 10). On the basis of these findings, the baby was diagnosed in utero with Pfeiffer syndrome type II. Following counseling, the pregnancy was terminated because polyhydramnios made the patient's symptoms more severe. The patient delivered her baby vaginally at 34 weeks of gestation. The baby's birth weight was 2,298 g; the baby was declared dead at 25 min after birth.

CONCLUSION

The detailed findings obtained by a combination of ultrasound that included three-dimensional and MR imaging and confirmation sought via molecular testing led to an accurate diagnosis of Pfeiffer syndrome type II in utero.

Demonstration of cranial sutures and fontanelles at 15 to 16 weeks of gestation: a comparison between two-dimensional and three-dimensional ultrasonography

OBJECTIVE

The purpose of this study was to evaluate the feasibility of obtaining good quality three-dimensional ultrasound pictures of the cranial sutures and fontanelles and to compare between two-dimensional and three-dimensional ultrasound in identifying the normal appearance of cranial sutures and fontanelles by the transvaginal approach at 15 to 16 weeks of gestation.

METHODS

Fifty fetuses were prospectively evaluated by two-dimensional and three-dimensional transvaginal sonography between 15 and 16 weeks of gestation. The sagittal, coronal, lambdoidal, and metopic sutures, as well as anterior and posterior fontanelles, were inspected.

RESULTS

Three-dimensional ultrasound enabled visualization of all sutures in 37 (74%) fetuses compared to 28 (56%) fetuses examined by two-dimensional ultrasonography (p = NS). The visualization of the sagittal suture was significantly superior by three-dimensional ultrasonography compared to two-dimensional ultrasonography (50 (100%) vs 35 (70%), p < 0.001). No significant difference between the two modalities was found in visualization of the fontanelles.

CONCLUSION

Sutures and fontanelles are usually satisfactorily demonstrated by two-dimensional and three-dimensional ultrasound at 15 to 16 weeks of gestation. The sagittal suture is difficult to visualize using two-dimensional ultrasound, and three-dimensional ultrasound appears to be the best method for its demonstration.