Extreme fenestration of the basilar artery associated with cleft palate, nasopharyngeal mature teratoma, and hypophyseal duplication

Embryology of the vertebral artery and variants of the adult

The vertebral arteries represent in the adult the main blood supply of the posterior cranial fossa, even if they appear relatively late during the embryological life. We reviewed all the most important steps of the vertebral artery's embryological development and the most common variants that can occur in the adult. The aim of this review is to summarize the main events of the development of this artery and to give an embryological explication for the most common variants of this artery.

Anatomical variations of human vertebral and basilar arteries: A current review of the literature

The vertebral artery originates from the subclavian artery and is divided into four segments (V1-V4). In its intracranial segment (V4), the two vertebral arteries join to form the basilar artery, an unpaired medium-sized artery. However, apart from this typical description, several anatomical variations may occur in the human body. Although in some cases such variations may be asymptomatic, they may be also associated with several pathological conditions, neurological complications, surgical complications, and increased risk of developing vascular diseases. Therefore, it is crucial to obtain sufficient information on the anatomy and variants of both arteries to prevent such complications and ensure the safe completion of surgical and radiological treatments. For this reason, we reviewed studies published up to January 2022 concerning the reported variations of the vertebral artery and basilar artery regarding their origin, course, length, and diameter. We believe that the thorough presentation of these variations would help surgeons worldwide during their daily clinical and surgical practice.

Duplication of the Pituitary Gland: CT, MRI and DTI Findings and Updated Review of the Literature

Duplication of the pituitary gland (DPG) is an extremely rare malformation. DPG is associated with a wide variety of midline and central nervous system malformations (DPG-plus syndrome). We present the computed tomography (CT), magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) findings of a rare case of DPG with associated tuberomammillary fusion resulting in a hypothalamic mass-like configuration, oropharyngeal teratoma, cleft palate, hypertelorism, duplicated/broad sella, duplication/low bifurcation of the basilar artery, and craniovertebral midline anomalies. Qualitative interpretation of DTI yielded normal white matter organization of the brain. The duplication of the prechordal plate and the rostral end of the notochordal plate/notochord is thought to be the main factor leading to a duplication of the pituitary primordium and resulting in the formation of two morphologically normal glands. The time of induction of the teratogenic influence, the extent of the prechordal plate and notochordal plate/notochord abnormalities, and the faulty interactions are believed to be the reason for the wide spectrum of associated midline abnormalities.

An Approach to Nasopharyngeal Mass in Newborns: Case Series and Systematic Literature Review

OBJECTIVE

Congenital nasopharyngeal masses (CNMs) are rare. Presenting symptoms vary, and the differential diagnoses cover a wide spectrum of possibilities. As it is uncommon, most examples discussed in literature are described as case reports or series. Guidelines on CNM patient management do not exist. In this study, we present two (2) cases of neonates with CNMs that were encountered at our tertiary center. Additionally, to best elaborate a comprehensive, case-based approach to CNM management, we offer an up-to-date, diagnosis-to-treatment review of current literature.

METHODS

Case series and systematic literature review.

RESULTS

Twenty-eight (28) studies are included since January 2000 to October 2021, with a total of 41 cases. Most common diagnosis was teratoma (78%). Female-to-male ratio was 2.5:1. Twenty percent of cases presented prenatally with polyhydramnios or elevated alpha-fetoprotein. Postnatally, the presenting symptoms most frequently encountered were respiratory distress (78%), oral mass (52%), and feeding difficulties (29%). Seventy-five percent of affected newborns showed symptoms within the first 24 hours of life. Forty percent of cases had comorbidities, especially in the head and neck region.

CONCLUSIONS

Congenital nasopharyngeal masses can be detected antenatally, or symptomatically immediately after birth. Airway protection is a cornerstone in the management. Selecting the right imaging modality and convening a multidisciplinary team meeting are important toward the planning of next steps/therapeutic approach. Typically, a transnasal or transoral surgical approach will be deemed sufficient to address the problem, with a good overall prognosis.

CT and MRI of congenital nasal lesions in syndromic conditions

Congenital malformations of the nose can be associated with a variety of syndromes, including solitary median maxillary central incisor syndrome, CHARGE syndrome, Bosma syndrome, median cleft face syndrome, PHACES association, Bartsocas-Papas syndrome, Binder syndrome, duplication of the pituitary gland-plus syndrome and syndromic craniosynsotosis (e.g., Apert and Crouzon syndromes) among other craniofacial syndromes. Imaging with CT and MRI plays an important role in characterizing the nasal anomalies as well as the associated brain and cerebrovascular lesions, which can be explained by the intimate developmental relationship between the face and intracranial structures, as well as certain gene mutations. These conditions have characteristic imaging findings, which are reviewed in this article.

Oropharyngeal teratoma, oral duplication, cervical diplomyelia and anencephaly in a 22-week fetus: A review of the craniofacial teratoma syndrome

BACKGROUND

Oropharyngeal teratoma may occur by itself or together with other craniofacial malformations, most commonly cleft palate. Oropharyngeal teratoma may be also seen in association with frontonasal dysplasia and/or various degrees of craniofacial duplication. The nosology of these sporadic disorders is poorly defined.

CASE AND REVIEW

We report on a 22-week fetus with a protruding nasopharyngeal teratoma, partial oral duplication, anencephaly, multiple costo-vertebral segmentation defects, and cervical diplomyelia. A review of the literature identified 48 patients published from 1931 to 2013 with co-existing clefting and duplication anomalies of the cephalic pole. Thoracic and abdominal midline anomalies were reported 13 times.

CONCLUSION

The term "craniofacial teratoma syndrome" is introduced to define this phenotype as a recognizable developmental field defect of the cephalic pole. Developmental pathogenesis is discussed with a focus on pleiotropy and stereotaxis. The observation of midline findings suggestive of holoprosencephaly in a few previously reported cases suggests a role for the sonic hedgehog signaling pathway in this malformation pattern.

Cerebral arterial fenestrations

Arterial fenestrations are an anatomic variant with indeterminate significance. Given the controversy surrounding fenestrations we sought their prevalence within our practice along with their association with other cerebrovascular anomalies. We retrospectively reviewed 10,927 patients undergoing digital subtraction angiography between 1992 and 2011. Dictated reports were searched for the terms "fenestration" or "fenestrated" with images reviewed for relevance, yielding 228 unique cases. A Medline database search from February 1964 to January 2013 generated 304 citations, 127 cases of which were selected for analysis. Cerebral arterial fenestrations were identified in 228 patients (2.1%). At least one aneurysm was noted in 60.5% of patients, with an aneurysm arising from the fenestration in 19.6% of patients. Aneurysmal subarachnoid hemorrhage or non-aneurysmal subarachnoid hemorrhage were present in 60.1% and 15.8%, respectively. For the subset of patients with an aneurysm arising directly from a fenestration relative to those patients with an aneurysm not immediately associated with a fenestration, the prevalence of aneurysmal subarachnoid hemorrhage was 66.7% vs. 58.6% (p = 0.58). Fenestrations were more often within the posterior circulation (73.2%) than the anterior circulation (24.6%), though there was no difference in the prevalence of aneurysms within these groups (61.1% vs. 60.7%, p = 1.0). Cerebral arterial fenestrations are an anatomic variant more often manifesting at the anterior communicating arterial complex and basilar artery and with no definite pathological relationship with aneurysms.

Fenestrations of the basilar artery demonstrated on magnetic resonance angiograms: an analysis of 212 cases

Fenestration of the basilar artery (BA) is a rare variant of the intracranial artery, well demonstrated in autopsy and angiographic studies. Some angiographic series show a high incidence of associated aneurysms at the basilar fenestration site. The purpose of this study is to report the incidence of BA fenestration, its configurations, associated aneurysms, and arterial anomalies in a large series of intracranial MR angiograms (MRAs). A total of 16,416 MRAs were retrospectively reviewed to identify the location, size and associated intracranial arterial anomalies of BA fenestrations. All images were obtained with the time-of-flight (TOF) technique. Of the 16,416 MRAs, 215 fenestrations were found in 212 cases (1.29%). Most fenestrations were located in the proximal BA. The average length of the fenestration was 4.6 mm; the largest was 15.6 mm. No aneurysm was found at the site of the fenestration. Thirteen aneurysms were found in nine cases at locations other than the BA: seven in the middle cerebral artery (MCA), one in the anterior cerebral artery (ACA), one in the anterior communicating artery (Acom), one in the vertebral artery (VA), one at the carotid siphon, and two at the internal carotid-posterior communicating artery (IC-PC). Arterial anomalies in other locations were found in 26 cases. BA fenestrations were found in 1.29% of the 16,416 cases studied. There were no aneurysms at the BA fenestration site. Aneurysms at the BA fenestration site may be an exceedingly rare phenomenon.

Basilar artery fenestration detected with CT angiography

OBJECTIVES

To analyse the characteristics of basilar artery (BA) fenestrations and their coexistence with aneurysms and other anomalies in a massive cases by computed tomographic angiography (CTA).

METHODS

A total of 5,657 sequential cerebral CTA images performed from January 2006 to February 2012 were reviewed. CTA images were obtained from the raw datasets by using volume rendering and maximal intensity projection reconstruction.

RESULTS

One hundred and thirty-two (2.33 %) BA fenestrations were detected with CTA, and most common at the proximal segment (n = 124). BA fenestration-associated aneurysms were found in 34 cases and 7 located at the posterior circulation, and the frequency of posterior circulation aneurysms was significantly different in patients with and without BA fenestrations (P = 0.025). Other associated anomalies included arteriovenous malformation (n = 7) and moyamoya disease (n = 6). BA fenestrations were classified into Type I (74 cases), Type II (15 cases), Type III (41 cases) and Type IV (2 cases). A significant difference was observed between Types II + III associated with convex-lens-like and slit-like fenestrations (P = 0.008).

CONCLUSIONS

BA fenestrations were found in 2.33 % with CTA. They were significantly more often associated with posterior circulation aneurysms than those without BA fenestration. The anterior inferior cerebral artery (AICA) tends to originate more often from convex-lens-like fenestration than slit-like.

KEY POINTS

• Basilar artery fenestrations were found in 2.33 % of patients undergoing CT angiography. • Fenestrations were seen more often in the lower third with slit-like configurations. • No obvious relationship exists between basilar artery fenestration and aneurysm formation. • Basilar artery fenestrations perhaps predispose a patient to posterior circulation aneurysm formation. • The AICA tends to originate more often from convex-lens-like than slit-like fenestrations.

Duplication of the pituitary gland associated with multiple blastogenesis defects: Duplication of the pituitary gland (DPG)-plus syndrome. Case report and review of literature

Background:

Duplication of the pituitary gland (DPG) is a rare craniofacial developmental anomaly occurring during blastogenesis with postulated etiology such as incomplete twinning, teratogens, median cleft face syndrome or splitting of the notochord. The complex craniocaudal spectrum of blastogenesis defects associated with DPG is examined with an illustrative case.

Case Description:

We report for the first time in the medical literature some unique associations with DPG, such as a clival encephalocele, third cerebral peduncle, duplicate odontoid process and a double tongue with independent volitional control. This patient also has the previously reported common associations such as duplicated sella, cleft palate, hypertelorism, callosal agenesis, hypothalamic enlargement, nasopharyngeal teratoma, fenestrated basilar artery and supernumerary teeth. This study also reviews 37 cases of DPG identified through MEDLINE literature search from 1880 to 2011. It provides a detailed analysis of the current case through physical examination and imaging.

Conclusion:

The authors propose that the developmental deformities associated with duplication of pituitary gland (DPG) occur as part of a developmental continuum, not as chance associations. Considering the fact that DPG is uniquely and certainly present throughout the spectrum of these blastogenesis defects, we suggest the term DPG-plus syndrome.

Pituitary duplication with nasopharyngeal teratoma and cleft palate

Pituitary gland duplication is a rare malformation of unknown cause that is often associated with a nasopharyngeal teratoma, among other secondary malformations. This clinical report describes a case of pituitary gland duplication with a nasopharyngeal teratoma, cleft palate, and hypothalamic hamartoma, as well as the surgical management of this patient. This case also raises the question of whether the nasopharyngeal teratoma is the cause of the pituitary duplication above and the cleft palate below or whether it is a result of the primary duplication of the notochordal process. Various theories are presented in an attempt to answer this question, but the exact cause of these malformations remains equivocal. Future research in this topic may elucidate the answer to this question.

Fenestrations of the intracranial vertebrobasilar system diagnosed by MR angiography

INTRODUCTION

Fenestrations of cerebral arteries are most common in the vertebrobasilar (VB) system, and magnetic resonance (MR) angiographic studies of these variations are sparse.

METHODS

We retrospectively reviewed MR angiographic images of 3,327 patients; images were obtained using two 1.5-T imagers and picked up fenestrations of the intracranial vertebral artery (VA), VB junction, and basilar artery (BA) for evaluation.

RESULTS

In 92 patients, we found 93 fenestrations (2.80%), which included 18 of the intracranial VA (0.54% prevalence), 6 of the VB junction (0.18%), and 69 of the BA (2.07%). Most VA fenestrations were large, and the posterior inferior cerebellar artery arose from the fenestrated segment in 10 patients (56%). Fenestrations of the VB junction were small and triangular. Sixty-five (94%) of the 69 BA fenestrations were located at the proximal segment and had small slit-like configurations. The anterior inferior cerebellar artery arose from the fenestrated segment in 27 patients (37%). We found 18 cerebral aneurysms in 16 (17%) of the 92 patients with fenestration but detected only one aneurysm at the fenestration.

CONCLUSION

The overall prevalence of fenestrations of the intracranial VB system was 2.77%. We found associated cerebral aneurysms relatively frequently but rarely at the fenestration.

Normal and abnormal embryology and development of the intracranial vascular system

The brain vascular system develops in such a way that it continuously adapts the supply of oxygen and other nutrients to the needs of the parenchyma. To accompany the developing brain vesicles, it evolves in several steps: superficial meningeal network first; intraventricular choroid plexuses which determine the arterial pattern; penetrating capillaries from the surface to the ventricular germinal matrix forming simple transcerebral arteriovenous loops; cortical capillaries last, mainly in the last trimester. The venous return becomes connected to both the surface and to the choroidal veins, so forming distinct meningeal and subependymal venous drainage systems, while the arteries are on the surface only. While the arterial system was determined early (week 8), the venous system is continuously remodeled by the morphological changes of the base of the skull and the expansion of the brain vesicles. Until late in gestation, the vascular system is made of simple endothelial channels in which the arterial or venous fate is determined primarily by the direction of flow.

Congenital pathology of the pituitary gland and parasellar region

The adenohypophysis and neurohypophysis originate from the combination of 2 events occurring during the fourth week of life, the development of Rathke pouch and of a neuroectodermal evagination of tissue from the floor of the diencephalon. Congenital pathology of the pituitary gland and parasellar regions derives from abnormalities of these coordinated events. In this article, we review the pathogenesis, clinical presentation, and imaging features of common and rare congenital disorders of the region of the sella turcica.

Pituitary duplication and nasopharyngeal teratoma in a newborn: CT, MRI, US and correlative histopathological findings

The computed tomography and MRI imaging findings in a case of pituitary duplication and epipharyngeal teratoma are described in a newborn baby girl with respiratory difficulties. Associated skull base and central nervous system malformations are presented. Teratoma diagnosis was confirmed by histology. The embryological pathogenesis is discussed.

Craniofacial defects of blastogenesis: duplication of pituitary with cleft palate and orophgaryngeal tumors

Duplications of organs and/or tissues are rare in morphogenesis and have frequently been attributed to incomplete twinning. To further elucidate the phenotypes associated with organ duplications, we present three infants with duplication of the pituitary gland (DPG). A review of previously reported cases with DPG showed that the commonest additional findings were hypothalamic enlargement, a broad or duplicated sella, cleft palate, hypertelorism, oropharyngeal tumors, agenesis or hypoplasia of the corpus callosum, and abnormalities of vertebrae. DPG and additional malformations constitute a distinct and recognizable pattern of anomalies, which may constitute a polytopic field defect due to splitting of the notochord. However, the precise inductive mechanism resulting in DPG remains unknown.

Duplication of the hypophysis associated with precocious puberty: presentation of two cases and review of pituitary embryogenesis

Pituitary duplication is a rare malformation commonly associated with other major neural/craniofacial anomalies, easily shown by magnetic resonance imaging. The authors describe two girls with duplication of the pituitary gland and thickening of the hypothalamus, facial dysmorphism and precocious pubertal development. The pathogenesis of pituitary duplication and its relationship with precocious pubertal development are discussed.