Abnormal venous drainage in syndromic craniosynostosis and the role of CT venography

Changes in Ventricular Volume After Posterior Vault Distraction Osteogenesis in Patients With Syndromic and Nonsyndromic Craniosynostosis

OBJECTIVE

Little is known about the response of the ventricular system to cranial vault surgery in patients with craniosynostosis. This study aims to evaluate the changes in the cerebral ventricular system in response to posterior vault distraction osteogenesis (PVDO) in patients with syndromic and nonsyndromic craniosynostosis.

METHODS

A single-institution retrospective review of all patients with craniosynostosis undergoing PVDO from 2000 to 2022 was completed. Patients were included for analysis if they had pre and postoperative cranial computed tomography scans. Ventricular volume (VV) and intracranial volume (ICV) were calculated using segmentation software.

RESULTS

Both patients with syndromic synostosis and nonsyndromic synostosis (NSS) experienced a significant increase in ICV after PVDO, but only patients with NSS experienced a significant VV change ( P = 0.004). After normalization by ICV, total, lateral, and third VV changes retained significance with percentage increases of 114%, 117%, and 89%, respectively ( P < 0.05 for all).

CONCLUSION

The differing results between cohorts reinforce the concept that the intracranial milieu is different between patients with syndromic synostosis and NSS. The results of the NSS cohort suggest that these patients may exist in a compensated state in which a reduction in cerebral blood flow and VV allows for the maintenance of parenchymal health to prevent the development of intracranial hypertension. Further studies may explore VV as a surrogate marker of ICP elevation, and the utility of cranial vault remodeling on nonsynostotic pathologies with cephalocranial disproportion.

The Outcomes of Endoscopic Suturectomy in Syndromic Craniosynostosis

OBJECTIVE

Endoscopic suturectomy is a widely practiced surgical option for infants with craniosynostosis. But the efficacy and safety of the procedure remain unclear in syndromic patients. This study aims to evaluate the efficacy and safety of endoscopic suturectomy for patients with syndromic craniosynostosis.

METHODS

From January 2013 to December 2020, 242 patients underwent endoscopic suturectomy at our institution. The surgical outcome was determined to be favorable or unfavorable based upon the necessity of an additional cranial surgery upon the last follow-up. First, we analyzed the outcomes of 26 syndromic craniosynostosis patients who have followed up for over a year. Second, we compared the outcomes between the syndromic (N=12) and nonsyndromic (N=11) patients with bilateral coronal synostosis who have followed up for over a year.

RESULTS

Twenty-three out of 26 syndromic craniosynostosis patients (88%) showed favorable outcomes without significant complications. In the analysis for bilateral coronal synostosis patients, 11 of 12 syndromic patients (92%) presented favorable outcomes, and all nonsyndromic patients showed favorable outcomes. No significant differences were observed in various anthropometric indices (cranial index, intracranial volume, anterior cranial height, anterior cranial base length, and cranial height-length index) and surgical outcomes between syndromic and nonsyndromic groups.

CONCLUSIONS

Endoscopic suturectomy has the potential to be a surgical option for syndromic craniosynostosis. Even for patients with unfavorable outcomes, endoscopic suturectomy could serve as a bridge treatment for infants to counter cranial deformation before additional extensive surgery.

What We Know About Intracranial Hypertension in Children With Syndromic Craniosynostosis

OBJECTIVE

A scoping review of literature about mechanisms leading to intracranial hypertension (ICH) in syndromic craniosynostosis (sCS) patients, followed by a narrative synopsis of whether cognitive and behavioral outcome in sCS is more related to genetic origins, rather than the result of ICH.

METHODS

The scoping review comprised of a search of keywords in EMBASE, MEDLINE, Web of science, Cochrane Central Register of Trials, and Google scholar databases. Abstracts were read and clinical articles were selected for full-text review and data were extracted using a structured template. A priori, the authors planned to analyze mechanistic questions about ICH in sCS by focusing on 2 key aspects, including (1) the criteria for determining ICH and (2) the role of component factors in the Monro-Kellie hypothesis/doctrine leading to ICH, that is, cerebral blood volume, cerebrospinal fluid (CSF), and the intracranial volume.

RESULTS

Of 1893 search results, 90 full-text articles met criteria for further analysis. (1) Invasive intracranial pressure measurements are the gold standard for determining ICH. Of noninvasive alternatives to determine ICH, ophthalmologic ones like fundoscopy and retinal thickness scans are the most researched. (2) The narrative review shows how the findings relate to ICH using the Monro-Kellie doctrine.

CONCLUSIONS

Development of ICH is influenced by different aspects of sCS: deflection of skull growth, obstructive sleep apnea, venous hypertension, obstruction of CSF flow, and possibly reduced CSF absorption. Problems in cognition and behavior are more likely because of genetic origin. Cortical thinning and problems in visual function are likely the result of ICH.

A Novel Direct Pathway of Dural Venous Outflow from the Basilar Venous Plexus via the Diploic Space of the Clivus

BACKGROUND

The internal jugular vein (IJV) is the pre-eminent outflow of the dural venous sinuses (DVS) in the supine position, while the vertebral venous plexus (VVP) dominates venous outflow in the upright position. Emissary veins can also be an accessory pathway for this venous egress. To our knowledge, alternative dural venous sinus directly drainage via the diploic space has not been previously reported in the literature.

METHODS

Ten fresh frozen adult cadavers underwent exposure of the basilar venous plexus. The entire plexus, still adhered to the underlying clivus, was removed with its underlying bone and submitted for histological examination following decalcification (Masson Trichrome, 5 μm slices).

RESULTS

All specimens were found to have direct communication between the basilar venous plexus and underlying diploic space of the clivus i.e., no intermediate clival emissary vein. These were concentrated near the midline and were more numerous over the clivus near the junction of the occipital and sphenoid bones. The endothelium of the venous sinus was continuous at the opening into the diploic space and these openings ranged in size from 500 to 750 μm (mean 650 μm).

CONCLUSIONS

An improved understanding of the cerebral venous drainage can assist clinicians and surgeons in recognizing normal, pathologic, and variant anatomy in this region. Based on our study, direct venous sinus (DVS) to diploic space drainage offers an additional pathway for venous egress from the intracranium. Therefore, removal of the dura over the clivus during various skull base procedures might be associated with increased venous bleeding from the basilar venous plexus on its deep surface where it interfaces with the clivus.

Preservation of Enlarged Mastoid Emissary Vein during Microvascular Decompression for Trigeminal Neuralgia Accompanied by Abnormal Venous Drainage: A Technical Case Report

During microvascular decompression (MVD) for trigeminal neuralgia (TGN), the mastoid emissary veins (MEV) are routinely sacrificed using the suboccipital retrosigmoid approach. The technical nuances when the MEV is an important collateral venous pathway for the obstructive internal jugular vein (IJV) have not been described thus far. Herein, we demonstrate for the first time a modified surgical technique for MVD to preserve the MEV. A 62-year-old man with a 10-year history of TGN refractory to carbamazepine was referred to our hospital for MVD. Preoperative imaging revealed that the superior cerebellar artery was the offending vessel. Computed tomography angiography also revealed that his contralateral IJV pathway was hypoplastic, and the ipsilateral pathway was severely stenosed by the external compression of the elongated styloid process and the transverse process of the first cervical vertebra. The ipsilateral MEV and the connecting occipital veins were enlarged as the sole collateral pathways of intracranial venous drainage. A modified MVD technique, including an upside-down L-shaped skin incision, layer-by-layer dissection of the occipital muscles, and denuding of the intraosseous part of the MEV, was used to cure the TGN with the preservation of the venous pathway. After surgery, the pain completely diminished without any complications. In conclusion, such technical modifications would be applicable in cases where the MEV needs to be preserved during posterior fossa surgery. Preoperative screening of the venous system is also recommended.

Craniovascular variation in four late Holocene human samples from southern South America

Craniovascular traits in the endocranium (traces of middle meningeal vessels and dural venous sinuses, emissary foramina) provide evidence of vascular anatomy in osteological samples. We investigate the craniovascular variation in four South American samples and the effect of artificial cranial modifications (ACM). CT scans of human adult crania from four archeological samples from southern South America (including skulls with ACM) are used for the analyses. The craniovascular features in the four samples are described, skulls with and without ACM are compared, and additionally, South Americans are compared to a previously analyzed sample of Europeans. Of the four South American samples, the Southern Patagonian differs the most, showing the most distinct cranial dimensions, no ACM, and larger diameters of the emissary foramina. Unlike previous studies, we did not find any major differences in craniovascular features between modified and non-modified skulls, except that the skulls with ACM present somewhat smaller foramina. South Americans significantly differed from Europeans, especially in the anteroposterior dominance of the middle meningeal artery, in the pattern of sinus confluence, in the occurrence of enlarged occipito-marginal sinuses, and in foramina frequencies and diameters. Craniovascular morphology is not affected by the cranial size, even in skulls with ACM, indicating a minor or null influence of structural topological factors. Concerning the samples from distinct geographic and climatic environments, it must be evaluated whether the craniovascular morphogenesis might be partially influenced by specific functions possibly associated with thermoregulation, intracranial pressure, and the maintenance of intracranial homeostasis.

Radiological and Morphometric Study of the Emissary Foramens and Canal in the Posterior Cranial Fossa of the Human Skull with Its Neurosurgical Significance

Objective  The posterior condylar canals (PCCs), posterior condylar veins (PCVs), occipital foramen (OF), and occipital emissary vein (OEV) are potential anatomical landmarks for surgical approaches through the lateral foramen magnum. We performed the study to make morphometric and radiological analyses of the various emissary foramens and vein in the posterior cranial fossa. Methods  Morphometric study were performed on 95 dry occipital bones and radiological analyses on computed tomography (CT) angiography images of 150 patients. The number of OFs on both sides was recorded and PCC length and mean diameters of the internal and external orifices of PCC were measured for bony specimens. Prevalence of PCV and PCV size was investigated using CT angiography. Results  Mean PCC length was higher in the left side (9.85 ± 2.5). Mean diameter of the internal orifice and the external orifice diameter were almost the same. The majority of PCCs (75-79.33%) had 2 to 5 mm diameter; only 4 to 9.2% were small in size (< 2 mm). In CT angiography, PCV was not identified in 23 (15.33%) patients. PCVs were located bilaterally in 105 (70%) and unilaterally in 22 (20.5%) patients. Only 11.3% of PCVs were large in size (> 5 mm), 80% of PCVs were medium sized (2-5 mm), and 8.6% were small sized (< 2 mm). Conclusion  Normal values of OF, PCC, PCV, and OEV could serve as a future reference for the understanding of the physiology of craniocervical venous drainage, which is necessary to avoid surgical complications and can also serve as a guide to surgical interventions for pathologies of the posterior cranial fossa, such as tumors and injuries.

Diploic vein morphology in normal and craniosynostotic adult human skulls

Diploic veins (DV) run within the cranial diploe, where they leave channels that can be studied in osteological samples. This study investigates overall DV variability in human adults and the effects of sex, age, cranial dimensions, and dysmorphogenesis associated with craniosynostosis (CS). The morphology of macroscopic diploic channels was analyzed in a set of the qualitative and quantitative variables in computed tomography-images of crania of anatomically normal and craniosynostotic adult individuals. Macroscopic diploic channels occur most frequently in the frontal and parietal bones, often with a bilaterally symmetrical pattern. DV-features (especially DV-pattern) are characterized by high individual diversity. On average, there are 5.4 ± 3.5 large macroscopic channels (with diameters >1 mm) per individual, with a mean diameter of 1.7 ± 0.4 mm. Age and sex have minor effects on DV, and cranial proportions significantly influence DV only in CS skulls. CS is associated with changes in the DV numbers, distributions, and diameters. Craniosynostotic skulls, especially brachycephalic skulls, generally present smaller DV diameters, and dolichocephalic skulls display increased number of frontal DV. CS, associated with altered cranial dimensions, suture imbalance, increased intracranial pressure, and with changes of the endocranial craniovascular system, significantly also affects the macroscopic morphology of DV in adults, in terms of both structural (topological redistribution) and functional factors. The research on craniovascular morphology and CS may be of interest in biological anthropology, paleopathology, medicine (e.g., surgical planning), but also in zoology and paleontology.

Changes in venous drainage after posterior cranial vault distraction and foramen magnum decompression in syndromic craniosynostosis

OBJECTIVE

The authors' objective was to measure the effect of posterior cranial vault distraction (PCVD) plus foramen magnum decompression (FMD) on dural sinus volume and venous flow in patients with syndromic craniosynostosis.

METHODS

The volumes of the sagittal, straight, transverse, and sigmoid sinuses of 5 consecutive patients with syndromic craniosynostosis who underwent PCVD+FMD were calculated in cubic centimeters with T2-weighted volumetric MRI sequences before surgery, immediately after surgery, and after the end of the distraction process. Tridimensional reconstructions of phase-contrast magnetic resonance angiography (PC-MRA) images were obtained with multiplanar reconstruction (MPR).

RESULTS

The average total volume of all dural sinuses increased immediately after surgery (from 10.06 cm3 to 12.64 cm3) and continued to increase throughout the 30-day distraction period (from 12.64 cm3 to 14.71 cm3) (p = 0.04), except that the right sigmoid sinus remained stable after the initial increase. The most important increases were observed for the left transverse sinus (+113.2%), right transverse sinus (+104.3%), left sigmoid sinus (+91.3%), and sagittal sinus (+41.8%). Less important modifications were evident for the right sigmoid sinus (+33.7%) and straight sinus (+23.4%). Significant improvements in venous flow were noted on the tridimensional reconstructions of the PC-MRA images. Venous obstruction grading score improved in 4 patients (average [range] 2.4 [ 2-5]) (p = 0.023) and remained stable in 1 patient. All patients had chronic tonsillar herniation (CTH) (mean [range] 16.6 [8-26] mm), and 3 had syringomyelia. CTH showed improvement on the last follow-up MRI evaluation in 4 patients (mean [range] 10.5 [0-25] mm) and worsened from 15 mm to 19 mm in 1 patient. Syringomyelia improved in 2 patients and remained unchanged in 1.

CONCLUSIONS

This study has provided the first radiological evidence of the impact of craniofacial surgery on dural sinus anatomy and venous drainage. The venous anomalies described in patients with syndromic craniosynostosis are not static, and PCVD+FMD triggers a dynamic process that can lead to significant modifications of intracranial venous drainage. The traction exerted by the distracted bone flap onto the occipitoparietal dura mater adherent to the inner calvaria may account for the enlargement of the dural sinus throughout the distraction period. The impact of these modifications on venous pressure, intracranial pressure, CTH, and hydrocephalus remains to be determined.

Craniovascular traits and braincase morphology in craniosynostotic human skulls

Middle meningeal vessels, dural venous sinuses, and emissary veins leave imprints and canals in the endocranium, and thus provide evidence of vascular patterns in osteological samples. This paper investigates whether craniovascular morphology undergoes changes in craniosynostotic human skulls, and if specific alterations may reflect structural and functional relationships in the cranium. The analyzed osteological sample consists of adult individuals with craniosynostoses generally associated with dolichocephalic or brachycephalic proportions, and a control sample of anatomically normal adult skulls. The pattern and dominance of the middle meningeal artery, the morphology of the confluence of the sinuses, and the size and number of the emissary foramina were evaluated. Craniovascular morphology was more diverse in craniosynostotic skulls than in anatomically normal skulls. The craniosynostotic skulls often displayed enlarged occipito-marginal sinuses and more numerous emissary foramina. The craniosynostotic skulls associated with more brachycephalic morphology often presented enlarged emissary foramina, while the craniosynostotic skulls associated with dolichocephalic effects frequently displayed more developed posterior branches of the middle meningeal artery. The course and morphology of the middle meningeal vessels, dural venous sinuses, and emissary veins in craniosynostotic skulls can be related to the redistribution of growth forces, higher intracranial pressure, venous hypertension, or thermal constraints. These functional and structural changes are of interest in both anthropology and medicine, involving epigenetic traits that concern the functional and ontogenetic balance between soft and hard tissues.

Venous anomalies in hypoplastic posterior fossa: unsolved questions

INTRODUCTION

Anomalous intracranial venous anatomy is described in patients with syndromic craniosynostosis and is of significant importance when it comes to surgical morbidity. However, it is still controversial its origin, type of circulation in each syndrome, how it behaves over time, when it can be interrupted and wether it needs to be studied. The purpose of this paper is to discuss these issues by reviewing the literature.

METHODS

A literature search was performed using the PubMed database with a focus on papers including detailed descriptions of the venous outflow in complex and syndromic craniosynostosis. Search details used were the following: ("veins"[MeSH Terms] OR "veins"[All Fields] OR "venous"[All Fields]) AND ("abnormalities"[Subheading] OR "abnormalities"[All Fields] OR "anomalies"[All Fields]) AND syndromic[All Fields] AND ("craniosynostoses" [MeSH Terms] OR "craniosynostoses"[All Fields] OR "craniosynostosis"[All Fields]). Studies that exposed details of venous anomalies found in syndromic or complex craniosynostosis were selected.

RESULTS

Of a total of 211 articles found, 11 were selected for this review. Of these, 5 were case reports, 5 retrospective studies, and only 1 prospective study. From the 6 series of cases presented, 5 discussed the relationship between jugular foramen stenosis (JFS) and collateral venous drainage. The authors discuss data from the literature for each leading question presented: 1-collateral circulation: is it an intrinsic trouble, a consequence of stenosis of the cranial base foramina or related to raised intracranial pressure (ICP)?; 2-what venous anomalies should we search for, and what is the best exam to study them?; 3-collateral circulation changes with time?; 4-can neurosurgeons interrupt the collateral circulation?; 5-should we study all complex types of craniosynostosis?

CONCLUSION

The importance of the study of the venous outflow in patients with complex craniosynostosis is evident in the literature. The real relationship between intracranial hypertension, hypoplastic skull base foramen, Chiari I malformation, hydrocephalus, and venous collateral circulation remains unknown. Prospective studies focusing on molecular biology analysis will possibly solve all of these leading questions.

Sinus pericranii-unusual anatomic obstacle to posterior decompression on an amniotic band sequence

Abnormal venous drainage in patients with craniofacial anomalies is relativity uncommon. Sinus pericranii is a rare vascular malformation characterized by communication between intracranial dural sinuses and extracranial venous drainage systems. The association between sinus pericranii and amniotic band syndrome has not been described. We report on a 7-month-old girl diagnosed with amniotic band sequence who underwent posterior fossa decompression due to intracranial hypertension and Chiari malformation type I. The computed tomography and magnetic resonance identified the connection between the sagittal sinus and the scalp. During the operation, the presence of sinus pericranii was a complicating factor limiting the proper exposure because of the risk of bleeding. Patients with craniofacial anomalies and sinus pericranii present an increased risk of serious surgical complications and consequences from craniofacial surgery, especially from cranioplasty and posterior decompression. Special attention must be paid to abnormal venous drainage, and vascular imaging studies are sometimes required.

Saethre-Chotzen syndrome: long-term outcome of a syndrome-specific management protocol

AIM

To assess the long-term outcomes of our management protocol for Saethre-Chotzen syndrome, which includes one-stage fronto-orbital advancement.

METHOD

All patients born with Saethre-Chotzen syndrome between January 1992 and March 2017 were included. Evaluated parameters included occipital frontal head circumference (OFC), fundoscopy, neuroimaging (ventricular size, tonsillar position, and the presence of collaterals/an abnormal transverse sinus), polysomnography, and ophthalmological outcomes. The relationship between papilledema and its associated risk factors was evaluated with Fisher's exact test.

RESULTS

Thirty-two patients (21 females, 11 males) were included. Median (SD) age at first surgery was 9.6 months (3.1mo) for patients who were primarily referred to our center (range: 3.6-13.0mo), the median (SD) age at last follow-up was 13 years (5y 7mo; range: 3-25y). Seven patients had papilledema preoperatively, which recurred in two. Two patients had papilledema solely after first surgery. Second cranial vault expansion was indicated in 20%. Thirteen patients had an OFC deflection, indicating restricted skull growth, one patient had ventriculomegaly, and none developed hydrocephalus. Eleven patients had emissary veins, while the transverse sinus was aberrant unilaterally in 13 (hypoplastic n=10 and absent n=3). Four patients had mild tonsillar descent, one of which was a Chiari type I malformation. Four patients had obstructive sleep apnoea (two mild, one moderate, and one severe). An aberrant transverse sinus was associated with papilledema (p=0.01).

INTERPRETATION

Single one-stage fronto-orbital advancement was sufficient to prevent intracranial hypertension for 80% of our patients with Saethre-Chotzen syndrome. Follow-up should focus on OFC deflection and venous anomalies.

Bilateral Severely Stenotic Jugular Foramen: Diagnosis and Management from the Otologist/Neurotologist Point of View

Bilateral jugular foramen stenosis with jugular bulb and vein aplasia is rare in nonsyndromic craniosynostosis and usually diagnosed during childhood. We present a case of bilateral jugular foramen stenosis with jugular bulb and vein aplasia, with subsequent persistence and enlargement of the fetal venous anastomosis in the middle and posterior cranial fossa, along with a review of the literature about this anatomical abnormality, highlighting the surgical challenges and management from the otologist/neurotologist point of view.

Dural sinus volume in children with syndromic craniosynostosis and intracranial hypertension

OBJECTIVE

Intracranial hypertension is a major concern in children with syndromic craniosynostosis (sCS). Cerebral venous hypertension caused by cerebral venous outflow obstruction is believed to contribute to intracranial hypertension. The authors therefore hypothesized that cerebral venous volume would be increased in those children with sCS and intracranial hypertension.

METHODS

In a case series of 105 children with sCS, of whom 32 had intracranial hypertension, cerebral MRI techniques were used to quantify the volume of the superior sagittal sinus, straight sinus (StrS), and both transverse sinuses.

RESULTS

Linear regression showed that total cerebral venous volume increased by 580.8 mm3 per cm increase in occipitofrontal head circumference (p < 0.001). No significant difference was found between the intracranial hypertension group and the nonintracranial hypertension group (p = 0.470). Multivariate ANOVA showed increased StrS volume (as a proportion of total volume) in the intracranial hypertension group (8.5% vs 5.1% in the nonintracranial hypertension group, p < 0.001). Multivariate logistic regression showed that a 100-mm3 increase in StrS volume is associated with increased odds of having intracranial hypertension by 60% (OR 1.60, 95% CI 1.24-2.08).

CONCLUSIONS

Although intracranial hypertension was not associated with total cerebral venous volume increase, it was associated with an isolated increase in StrS volume. Hence, it is unlikely that general cerebral venous outflow obstruction is the mechanism of intracranial hypertension in sCS. Rather, these findings indicate either a central cerebral vulnerability to intracranial hypertension or a mechanism involving venous blood redistribution.

Venous pathologies in paediatric neuroradiology: from foetal to adolescent life

The interpretation of cerebral venous pathologies in paediatric practice is challenging as there are several normal anatomical variants, and the pathologies are diverse, involving the venous system through direct and indirect mechanisms. This paper aims to provide a comprehensive review of these entities, as their awareness can avoid potential diagnostic pitfalls. We also propose a practical classification system of paediatric cerebral venous pathologies, which will enable more accurate reporting of the neuroimaging findings, as relevant to the underlying pathogenesis of these conditions. The proposed classification system comprises of the following main groups: arterio-venous shunting-related disorders, primary venous malformations and veno-occlusive disorders. A multimodal imaging approach has been included in the relevant subsections, with a brief overview of the modality-specific pitfalls that can also limit interpretation of the neuroimaging. The article also summarises the current literature and international practices in terms of management options and outcomes in specific disease entities.

Evaluation of the Mastoid Emissary Canals with Computerized Tomography in Patients with Chronic Otitis Media

Background  The mastoid emissary veins (MEVs) pass through the mastoid emissary canal-mastoid foramen (MEC-MF) in the mastoid region of the skull. MEVs can give rise to complications during surgical procedures. The purpose of our study was to investigate the morphological and morphometric characteristics of MECs of patients with clinical chronic otitis media (COM) using high-resolution computed tomography (HRCT). Methods  Patients diagnosed with COM and undergoing temporal HRCT were identified by retrospectively scanning our hospital's automation system. Patients undergoing temporal HRCT for reasons other than COM, infection or tinnitus were identified for the control group by scanning the PACS archive. Sixty-two mastoid regions were examined in 38 unilateral and 12 bilateral COM patients, and 100 mastoid regions in the 50 patients in the control group. The presence of an accessory MEC-MF and MEC-MF diameters was evaluated in both groups. Results  Main MEC diameters on the side of the ear with COM were 1.6 mm, and total accessory and main MEC diameters were 1.8 mm, both values being significantly higher than in the control group. Presence of accessory MEC on the side of the ear with COM was determined at 61.8%, significantly higher than in the control group. Conclusion  Preoperative awareness of cranial venous drainage abnormalities is important to reduce surgical complications. Our study shows that MECs may be wider in diameter in patients with COM. MECs in COM patients must be identified before surgery to the mastoid region.

Chiari 1 malformation and untreated sagittal synostosis: a new subset of complex Chiari?

PURPOSE

Chiari 1 malformation (CM1) is a well-known association with complex craniosynostosis (CC), while it has been rarely reported in association with monosynostosis. The aim of the present study is to investigate on the association between CM1 and untreated sagittal synostosis (USS).

METHOD

The study included 48 cases of sagittal synostosis (SS), untreated for misdiagnosis and associated with CM1. The children were firstly diagnosed for CM1 by MRI (mean age 9) than for SS (mean age 10.5) by three-dimensional computerized tomography (3D-CT), which documented the absence of the sagittal suture, in the presence of residual indentation of all the other sutures. Syndromic cases were diagnosed by clinical evaluation and molecular studies.

RESULTS

Of the 48 children harboring CM1 plus USS, 21 were asymptomatic for CM1 and are still on follow-up, while 27 children were operated for syringomyelia and scoliosis and/or occurrence of symptoms, three of them had an acute presentation (two papilledema and one sleep apneas) and 11 children had a documented increase of preoperative ICP. Craniovertebral decompression (CVD) was the first-line surgery in 24 children, 16 with duroplasty and five without and eight had also cerebellar (CBL) tonsil coagulation. A cranial vault remodelling was firstly performed in three children. Fifteen percent of children submitted to CVD needed a revision for cerebrospinal fluid (CSF) collection, while two needed both the supra- and infratentorial decompressive procedure and another two needed a treatment for the associated hydrocephalus.

CONCLUSIONS

The present study identified an USS in 27 (15.5%) of 174 CM1 children operated for a symptomatic CM1. We suggest to define this association CM1 plus USS, a new subtype of complex CM1. For the high percentage of complications and multiple procedures needed to solve the CM1, we advise to identify by 3D-CT scan these children before performing CVD. Our finding suggests also that, if left untreated, SS may lead to the delayed occurrence of a challenging subset of CM1.

Emissary veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa emissary veins: MR study

PURPOSE

The aim of this study was to find the prevalence of emissary veins and to compare the visibility of these emissary veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV).

MATERIALS AND METHODS

All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa emissary veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the emissary veins was compared with the dural venous sinus anatomic variations. p < 0.05 was considered statistically significant. An inter-observer reliability analysis was performed.

RESULTS

The prevalence of emissary veins in MRI was found in the right mastoid emissary vein (MEV) 82.7% and left MEV 81.4%. Occipital emissary vein (OEV) was present in 63 patients (28.6%) for the first radiologist (R1), and it was present in 61 patients (27.7%) for the second radiologist (R2) (K = 0.978). A statistically significant correlation was detected between the diameter of the left MEV and gender (p < 0.05) for both radiologists. There was a statistically significant difference between the left MEV and OEV and transverse sinus anatomic variations.

CONCLUSION

MR imaging is a noninvasive and irradiating imaging method for detecting posterior fossa major emissary veins, and we recommend using MR imaging for preoperative evaluation of posterior fossa major emissary veins and related dural venous sinuses.

Intracranial Venous Hypertension in Craniosynostosis: Mechanistic Underpinnings and Therapeutic Implications

Patients with complex, multisutural, and syndromic craniosynostosis (CSO) frequently exhibit intracranial hypertension. The intracranial hypertension cannot be entirely attributed to the craniocephalic disproportion with calvarial restriction because cranial vault expansion has not consistently alleviated elevated intracranial pressure. Evidence has most strongly supported a multifactorial interaction, including venous hypertension along with other pathogenic processes. Patients with CSO exhibit marked venous anomalies, including stenosis of the jugular-sigmoid complex, transverse sinuses, and extensive transosseous venous collaterals. These abnormal intracranial-extracranial occipital venous collaterals might represent anomalous development, with persistence and subsequent enlargement of channels normally present in the fetus, either as a primary defect or as nonregression in response to failure of the development of the jugular-sigmoid complexes. It has been suggested by some investigators that venous hypertension in patients with CSO could be treated directly via jugular foraminoplasty, venous stenting, or jugular venous bypass, although these options are not in common clinical practice. Obstructive sleep apnea, occurring as a consequence of midface hypoplasia, can also contribute to intracranial hypertension in patients with syndromic CSO. Thus, correction of facial deformities, as well as posterior fossa decompression, could also play important roles in the treatment of intracranial hypertension. Determining the precise mechanistic underpinnings underlying intracranial hypertension in any given patient with CSO requires individualized evaluation and management.

Staged Raising of a Coronal Flap for Fronto-Orbital Advancement and Remodeling in Saethre-Chotzen Syndrome Complicated by Sinus Pericranii

This article reports the surgical management of a 3-month-old girl with Saethre-Chotzen syndrome, who presented with bicoronal synostosis and a large midline sinus pericranii with abnormal cerebral venous drainage via scalp veins. Raised intracranial pressure was demonstrated on monitoring, indicating the need for calvarial expansion necessitating a coronal access incision. A 2-staged delayed raising of the coronal flap was performed to reduce the potential risk of cerebral venous infarction. Monitoring for clinical sequelae and a computerised tomography venogram followed each of these procedures, demonstrating successful redirection of the venous drainage of the brain posteriorly. Finally, a successful fronto-orbital advancement and remodeling procedure was performed with no complications.

Clinical Significance of Venous Anomalies in Syndromic Craniosynostosis

Background

The pattern of cranial venous drainage in syndromic craniosynostosis is unpredictable and not adequately understood. Collateral channels substitute for stenotic venous sinuses and pose potential risk for surgical intervention. The purpose of this study was to analyze the patterns of venous drainage in patients with syndromic craniosynostosis and their influence on operative planning and morbidity.

Methods

A retrospective study of patients with syndromic craniosynostosis from 2000 to 2013 was performed. Demographic data were collected including phenotype and associated pathologies. Pre- and/or postoperative venous imaging was reviewed for venous sinus stenosis, collateral emissaries, and persistent fetal sinuses. Categorization of anomalous venous drainage was performed, and the relationship with surgical morbidity was assessed.

Results

Forty-one patients were identified. Anomalies were present in 31 patients (76%) consisting of dural sinus stenosis in 28 (68%), dilated emissaries in 26 (63%), and fetal sinuses in 7 (17%). Pfeiffer syndrome was most commonly associated with anomalous drainage (100%). Venous anomalies were associated with elevated intracranial pressure (ICP), shunted hydrocephalus, Chiari malformations, and sleep apnea. In 5 cases, the surgical plan was adjusted based on anomalous anatomy. No mortalities occurred. Intraoperative complication rate was 7.3%, all with anomalous drainage. Median estimated blood loss was 1,100 cc for patients with anomalies versus 400 cc without anomalies (P = 0.181).

Conclusion

Cranial venous anomalies are commonly detected in patients with syndromic craniosynostosis and may affect surgical morbidity and outcome with a higher estimated blood loss, alteration of procedure, and postoperative morbidity. Detailed preoperative imaging of the venous drainage is therefore recommended in cases of syndromic synostosis.

Prevalence of Petrosquamosal Sinus and Its Clinical Significance: Radiologic Study and Meta-analysis

OBJECTIVE

The petrosquamosal sinus (PSS) is clinically important as it represents a potential hemorrhagic hazard during neurosurgical procedures. This double-approach radiologic study and meta-analysis aimed to assess the imaging characteristics of the PSS on computed tomography (CT) and systematically analyze its prevalence to improve imaging accuracy and assist in neurosurgical management.

METHODS

The retrospective radiologic study included CT scans of 388 patients aged 18 years or older. All patients with any visible intracranial pathologies or history of head trauma were excluded. To identify articles eligible for inclusion in our meta-analysis, an extensive search was conducted through PubMed, Embase, ScienceDirect, Web of Science, and CNKI. Data extracted included investigative method, prevalence of the PSS among subjects, ethnicity, gender, side, laterality, and mean diameter. The extracted data were pooled into a meta-analysis with a random-effects model.

RESULTS

The radiologic study showed that the PSS was visualized in 25.5% of the sides examined, that it was slightly more common among females (27.5%) than males (23.8%) and on the left (21.7%) than the right (29.4%). Its mean diameter was 1.14 ± 0.58 mm. The meta-analysis revealed that the overall prevalence of the PSS in the population is 11.1%, that it is more common in females (27.4%) than males (17.6%), and that a unilateral PSS is more common (78.2%) than a bilateral one (21.8%).

CONCLUSIONS

As a PSS is present in about one tenth of the population, it is important to consider the possibility that it is present when undertaking neurosurgical procedures and to assess preoperative CT scans to avoid complications.

Use of Multidirectional Cranial Distraction Osteogenesis for Cranial Expansion in Syndromic Craniosynostosis

Patients with syndromic craniosynostosis often require a large amount of cranial expansion to avoid intracranial hypertension, but the surgical procedure remains controversial. A patient of severe syndromic craniosynostosis with multiple bony defects and anomalous venous drainage at the occipital region was treated by multidirectional cranial distraction osteogenesis (MCDO) at the age of 8 months. Distraction started 5 days after surgery and ceased on postoperative day 16. The distraction devices were removed 27 days after completing distraction. After device removal, the increase of intracranial volume was 155 ml and the cephalic index was improved from 115.5 to 100.5. The resultant cranial shape was well maintained with minimal relapse at postoperative 9 months. In cases of syndromic craniosynostosis with multiple bony defects and/or anomalous venous drainage at the occipital region, expansion of the anterior cranium by MCDO is a viable alternative to conventional methods.

A Perioperative Risk Comparison of Posterior Vault Distraction Osteogenesis in an Older Pediatric Population

There is a growing literature on the advantages of posterior cranial vault distraction osteogenesis (PVDO) in infants, particularly those with syndromic and multisuture craniosynostosis. This study aims to compare perioperative outcomes of PVDO in older patients to those of infants. A prospective craniofacial database was queried for patients aged 5 and older undergoing PVDO; controls were diagnosis-matched infants. Demographic, perioperative, and distraction data was compared using a 2-sample t test and Fisher exact test.Twenty patients met inclusion criteria, and all had syndromic craniosynostosis. Mean age was 9.2 years for the older group, and 0.7 years for the younger. Older children had less weight-based blood loss (mean 58.6 ± 38.8 versus 14.6 ± 7.0 cc/kg, control versus older, P = 0.0092) and weight-based transfusion (mean 70.1 ± 37.2 versus 21.2 ± 9.9 cc/kg, control versus older, P = 0.0023); other perioperative variables were similar including duration of surgery, length of stay, distance distracted, time in consolidation, and length of follow-up. All patients in both groups successfully completed PVDO, and all older patients had resolution of papilledema and/or headaches. One from each group developed a wound infection that was treated with oral antibiotics.Posterior cranial vault distraction osteogenesis is a safe and efficacious for cranial vault expansion in syndromic craniosynostosis, with similar perioperative outcomes in older children as compared to infants. Posterior cranial vault distraction osteogenesis may be a reasonable alternative in older syndromic patients with acceptable frontal morphology and concerns for increased intracranial pressure.

Abnormal transcranial Doppler cerebral blood flow velocity and blood pressure profiles in children with syndromic craniosynostosis and papilledema

OBJECTIVE

Children with syndromic craniosynostosis are at risk of intracranial hypertension. This study aims to examine patient profiles of transcranial Doppler (TCD) cerebral blood flow velocity (CBFv) and systemic blood pressure (BP) in subjects with and without papilledema at the time of surgery, and subsequent effect of cranial vault expansion.

METHODS

Prospective study of patients treated at a national referral center. Patients underwent TCD of the middle cerebral artery 1 day before and 3 weeks after surgery. Measurements included mean CBFv, peak systolic velocity, and end diastolic velocity; age-corrected resistive index (RI) was calculated. Systemic BP was recorded. Papilledema was used to indicate intracranial hypertension.

RESULTS

Twelve patients (mean age 3.1 years, range 0.4-9.5) underwent TCD; 6 subjects had papilledema. Pre-operatively, patients with papilledema, in comparison to those without, had higher TCD values, RI, and BP (all p = 0.04); post-operatively, the distinction regarding BP remained (p = 0.04). There is a significant effect of time following vault surgery with a decrease in RI (p < 0.01).

CONCLUSION

Patients with syndromic craniosynostosis who have papilledema have a different TCD profile with raised BP. Vault surgery results in increased CBFv and decrease in RI, however the associated systemic BP response to intracranial hypertension remained at short-term follow-up.

Skull base morphology in fibroblast growth factor receptor type 2-related faciocraniosynostosis: a descriptive analysis

BACKGROUND

Children with faciocraniosynostosis present skull base abnormalities and may develop hydrocephalus or cerebellar tonsils ectopia (CTE). Several pathophysiological hypotheses were formulated in the past decades to explain these associations. However, no study has described in a genetically homogeneous population with confirmed fibroblast growth factor receptor type 2 (FGFR2) mutation eventual correlations between skull base abnormalities and hydrocephalus or CTE.

OBJECTIVE

To illustrate these features in children <2 years of age with a genetically confirmed FGFR2-related faciocraniosynostosis.

METHODS

We measured the foramen magnum area (FMA) and its sagittal and transversal components: the right, left, and mean area of the jugular foramen; the posterior fossa volume; and the cerebellar volume on preoperative millimetric computed tomography scan slices in 31 children with an FGFR2 mutation (14 with Crouzon syndrome, 11 with Apert syndrome, and 6 with Pfeiffer syndrome). They were compared with 17 children without synostosis. All children were <24 months of age. We correlated all these measures with the presence of hydrocephalus or CTE.

RESULTS

We observed a significantly small FMA in children with Crouzon (P = .03) and in children with Pfeiffer (P = .05) resulting from a reduced sagittal diameter (P = .02 for Crouzon and P = .002 for Pfeiffer). Hydrocephalus was associated with small FMA (P = .02). The jugular foramen area, posterior fossa volume, and cerebellar volume were not associated with hydrocephalus or CTE. Hydrocephalus and CTE were statistically associated (P = .002).

CONCLUSION

Hydrocephalus in FGFR2-related Crouzon and Pfeiffer syndromes is statistically associated with a small FMA. Hydrocephalus is statistically associated with CTE.

Spring-assisted cranial vault expansion in the setting of multisutural craniosynostosis and anomalous venous drainage: case report

Patients with multisutural craniosynostosis can develop anomalous venous connections between the intracranial sinuses and cutaneous venous system through enlarged emissary veins. Cranial vault remodeling in this subset of patients carries the risk of massive intraoperative blood loss and/or occlusion of collateral draining veins leading to intracranial venous hypertension and raised intracranial pressure, increasing the morbidity of cranial expansion. The authors report the use of spring-mediated expansion as a technique for cranial reconstruction in which the collateral intracranial venous drainage system can be preserved. A patient with bilateral lambdoid, sagittal, and unicoronal synostosis presented for cranial reconstruction. A tracheostomy and ventriculoperitoneal shunt were placed prior to intervention. At the time of reconstruction, a Luckenschadel skull abnormality and Chiari malformation Type I were present. A preoperative CT venogram demonstrated large collateral superficial occipital veins, small bilateral internal jugular veins, and hypoplastic jugular foramina. Collateral flow from the transverse and sigmoid sinuses through large occipital emissary veins was seen. Spring-mediated cranial vault expansion was performed with care to preserve the large collateral veins at the occipital midline. Four springs were placed at each lambdoid and the posterior and anterior sagittal sutures following 1-cm strip suturectomies. Removal of the springs was performed 2 months postoperatively. Cranial vault expansion was performed without disturbing the aberrant intracranial/extracranial venous collateral system. Estimated blood loss was 150 ml. A CT scan obtained 3 months postoperatively showed resolution of the Luckenschadel deformity and a 40% volumetric increase in the skull compared with the preoperative CT. Patients with anomalous venous drainage patterns and multisutural synostosis can undergo spring-mediated cranial vault expansion while preserving the major emissary veins draining the intracranial sinuses. Risks of blood loss, intracranial venous hypertension, and increased intracranial pressure may be decreased compared with traditional techniques of repair.

Diffusion Tensor Imaging and Fiber Tractography in Children with Craniosynostosis Syndromes

BACKGROUND AND PURPOSE

Patients with craniosynostosis syndromes caused by mutations in FGFR-2, FGFR-3, and TWIST1 genes are characterized by having prematurely fused skull sutures and skull base synchondroses, which result in a skull deformity and are accompanied by brain anomalies, including altered white matter microarchitecture. In this study, the reliability and reproducibility of DTI fiber tractography was investigated in these patients. The outcomes were compared with those of controls.

MATERIALS AND METHODS

DTI datasets were acquired with a 1.5T MR imaging system with 25 diffusion gradient orientations (voxel size = 1.8 × 1.8 × 3.0 mm(3), b-value = 1000 s/mm(2)). White matter tracts studied included the following: corpus callosum, cingulate gyrus, fornix, corticospinal tracts, and medial cerebellar peduncle. Tract pathways were reconstructed with ExploreDTI in 58 surgically treated patients with craniosynostosis syndromes and 7 controls (age range, 6-18 years).

RESULTS

Because of the brain deformity and abnormal ventricular shape and size, DTI fiber tractography was challenging to perform in patients with craniosynostosis syndromes. To provide reliable tracts, we adapted standard tracking protocols. Fractional anisotropy was equal to that in controls (0.44 versus 0.45 ± 0.02, P = .536), whereas mean, axial, and radial diffusivity parameters of the mean white matter were increased in patients with craniosynostosis syndromes (P < .001). No craniosynostosis syndrome-specific difference in DTI properties was seen for any of the fiber tracts studied in this work.

CONCLUSIONS

Performing DTI fiber tractography in patients with craniosynostosis syndromes was difficult due to partial volume effects caused by an anisotropic voxel size and deformed brain structures. Although these patients have a normal fiber organization, increased diffusivity parameters suggest abnormal microstructural tissue properties of the investigated white matter tracts.

Why should we report posterior fossa emissary veins?

Posterior fossa emissary veins are valveless veins that pass through cranial apertures. They participate in extracranial venous drainage of the posterior fossa dural sinuses. The mastoid emissary vein, condylar veins, occipital emissary vein, and petrosquamosal sinus are the major posterior fossa emissary veins. We believe that posterior fossa emissary veins can be detected by radiologists before surgery with a thorough understanding of their anatomy. Describing them using temporal bone computed tomography (CT), CT angiography, and cerebral magnetic resonance (MR) venography examinations results in more detailed and accurate preoperative radiological interpretation and has clinical importance. This pictorial essay reviews the anatomy of the major and clinically relevant posterior fossa emissary veins using high-resolution CT, CT angiography, and MR venography images and discusses the clinical importance of reporting these vascular variants.

Mechanics of the brain: perspectives, challenges, and opportunities

The human brain is the continuous subject of extensive investigation aimed at understanding its behavior and function. Despite a clear evidence that mechanical factors play an important role in regulating brain activity, current research efforts focus mainly on the biochemical or electrophysiological activity of the brain. Here, we show that classical mechanical concepts including deformations, stretch, strain, strain rate, pressure, and stress play a crucial role in modulating both brain form and brain function. This opinion piece synthesizes expertise in applied mathematics, solid and fluid mechanics, biomechanics, experimentation, material sciences, neuropathology, and neurosurgery to address today’s open questions at the forefront of neuromechanics. We critically review the current literature and discuss challenges related to neurodevelopment, cerebral edema, lissencephaly, polymicrogyria, hydrocephaly, craniectomy, spinal cord injury, tumor growth, traumatic brain injury, and shaken baby syndrome. The multi-disciplinary analysis of these various phenomena and pathologies presents new opportunities and suggests that mechanical modeling is a central tool to bridge the scales by synthesizing information from the molecular via the cellular and tissue all the way to the organ level.

Venous hypertension in syndromic and complex craniosynostosis: the abnormal anatomy of the jugular foramen and collaterals

Why craniosynostosis patients develop elevated intracranial pressure (ICP) is still a mystery. Our aim was to investigate jugular foramen size and its relation to venous hypertension and elevated ICP. Secondly, we evaluated whether occipital collateral veins develop as a compensatory mechanism for elevated ICP. We conducted a prospective study in 41 children with craniosynostosis who underwent a 3D-CT-angiography. We evaluated the anatomical course of the jugular vein, the diameter of the jugular foramen and the relation to the presence of papilledema. Additionally, we studied the anatomical variations of the cerebral venous drainage system. The diameter of the jugular foramen was significantly smaller in our patients. Abnormal venous collaterals were most often observed in patients with Apert, Crouzon-Pfeiffer and Saethre-Chotzen syndrome, even in children under two years of age. There was no significant difference in the number of collateral veins in patients with or without papilledema. Collaterals appear to reflect an inborn abnormality of the venous system, rather than a compensating mechanism for elevated ICP. This study confirms the presence of jugular foraminal narrowing in craniosynostosis patients and an abnormal venous system, which may predispose to elevated ICP.

LEVEL OF EVIDENCE

Diagnostic II.

Prevalence of clinically important posterior fossa emissary veins on CT angiography

Purpose:

We assessed the prevalence of the clinically important posterior fossa emissary veins detected on computed tomography (CT) angiography.

Materials and Methods:

A total of 182 consecutive patients who underwent 64-slice CT angiography were retrospectively reviewed to determine the clinically important posterior fossa emissary veins.

Results:

Of 166 patients, the mastoid emissary vein (MEV) was not identified in 37 (22.3%) patients. It was found bilaterally in 82 (49.4%) and unilaterally in 47 (28.3%) patients. Only six patients had more than one MEV that were very small (<2 mm), and only five patients had very large (>5 mm) veins. The posterior condylar vein (PCV) was not identified in 39 (23.5%) patients. It was found bilaterally in 97 (58.4%) and unilaterally in 30 (18.1%) patients. Only 15 patients had a very large (>5 mm) PCV. The petrosquamosal sinus (PSS) was identified only in one patient (0.6%) on the left side. The occipital sinus was found in two patients (1.2%).

Conclusions:

The presence of the clinically important posterior fossa emissary veins is not rare. Posterior fossa emissary veins should be identified and systematically reported, especially prior to surgeries involving the posterior fossa and mastoid region.

Anatomy and pathology of the cranial emissary veins: a review with surgical implications

Emissary veins connect the extracranial venous system with the intracranial venous sinuses. These include, but are not limited to, the posterior condyloid, mastoid, occipital, and parietal emissary veins. A review of the literature for the anatomy, embryology, pathology, and surgery of the intracranial emissary veins was performed. Detailed descriptions of these venous structures are lacking in the literature, and, to the authors', knowledge, this is the first detailed review to discuss the anatomy, pathology, anomalies, and clinical effects of the cranial emissary veins. Our hope is that such data will be useful to the neurosurgeon during surgery in the vicinity of the emissary veins.

Brain and ventricular volume in patients with syndromic and complex craniosynostosis

PURPOSE

Brain abnormalities in patients with syndromic craniosynostosis can either be a direct result of the genetic defect or develop secondary to compression due to craniosynostosis, raised ICP or hydrocephalus. Today it is unknown whether children with syndromic craniosynostosis have normal brain volumes. The purpose of this study was to evaluate brain and ventricular volume measurements in patients with syndromic and complex craniosynostosis. This knowledge will improve our understanding of brain development and the origin of raised intracranial pressure in syndromic craniosynostosis.

METHODS

Brain and ventricular volumes were calculated from MRI scans of patients with craniosynostosis, 0.3 to 18.3 years of age. Brain volume was compared to age matched controls from the literature. All patient charts were reviewed to look for possible predictors of brain and ventricular volume.

RESULTS

Total brain volume in syndromic craniosynostosis equals that of normal controls, in the age range of 1 to 12 years. Brain growth occurred particularly in the first 5 years of age, after which it stabilized. Within the studied population, ventricular volume was significantly larger in Apert syndrome compared to all other syndromes and in patients with a Chiari I malformation.

CONCLUSIONS

Patients with syndromic craniosynostosis have a normal total brain volume compared to normal controls. Increased ventricular volume is associated with Apert syndrome and Chiari I malformations, which is most commonly found in Crouzon syndrome. We advice screening of all patients with Apert and Crouzon syndrome for the development of enlarged ventricle volume and the presence of a Chiari I malformation.

The imaging of the cerebral venous sinuses

The cerebral venous sinuses in the past have been relatively neglected during radiological, neurological, and neurosurgical scientific discourse. However modern imaging and radiological approaches to treatment are demonstrating that far from being rare, the cerebral venous sinuses are involved in the pathogenesis of a protean list of ailments. During the review we hope to illustrate the imaging of diseases of the cerebral venous sinuses as demonstrated on multislice computer tomography and magnetic resonance imaging.

Craniosynostosis: a radiological and surgical perspective

Craniosynostosis is the premature fusion of the cranial sutures. It is identified early in life either due to cosmetic deformity or due to more serious functional complications. Isolated forms of craniosynostosis are much more common and less challenging in their management than their syndromic counterpart. Modern multislice computed tomography and 3D reconstructions have revolutionized surgical planning and follow-up. We review the radiological features of the craniosynostoses, complications, and associated conditions that may alter patient management. Common surgical techniques and postoperative appearances are illustrated in the article.