Agenesis of the internal carotid artery: associated malformations including a high rate of aortic and cardiac malformations

ICA agenesis with transcavernous anastomosis: a systematic review

PURPOSE

To present two cases of Internal Carotid Artery (ICA) agenesis and conduct a systematic review to assess for associations with other anomalies and intracranial aneurysms.

METHODOLOGY

We performed a retrospective review of published cases of patients with ICA agenesis with intercavernous anastomosis in MEDLINE database on August 2022 using search terms "internal carotid artery", "agenesis" and "transcavernous anastomosis". We also included two cases of ICA agenesis with type D collateral that we encountered.

RESULTS

Total of 45 studies that included 47 patients and two of our cases resulted in 49 patients. Only 70% of studies reported the location of a collateral vessel of which more than two-thirds were on the floor of sella. More than half of the vessels connected cavernous segments of ICA. A1 segment ipsilateral to the side of ICA agenesis was absent in most of the cases but was not true for all cases. Aneurysm was seen in more than one-quarter of the patients. It can also mimic microadenoma as in prior reported cases as well as in one of our cases.

CONCLUSION

ICA agenesis with type D collateral is a rare anomaly but clinically relevant due to the increased risk of an aneurysm or mimic microadenoma or false alarm for occlusion of ICA but knowledge of this rare variant can help in better management of these patients.

Agenesis of the right internal carotid artery and aqueductal stenosis in a child with hydrocephalus, the role of endoscopic third ventriculostomy: a case report

Agenesis of the internal carotid artery (aICA) is a rare congenital vascular condition that can affect one or both sides of the patient. Most patients remain asymptomatic, but ischemic/hemorrhagic stroke, intracranial aneurysm, and other neurologic findings can occur. CT scan can demonstrate the absence of the bony carotid canal and helps to differentiate a complete aICA from aplasia or hypoplasia. The association of aICA and aqueductal stenosis (AS) has never been reported in the literature. We report the case of a 9-year-old with agenesis of the right ICA associated with AS and hydrocephalus, which was treated successfully with an endoscopic third ventriculostomy (ETV). We review the literature looking for the association of the clinical findings and the evolution of the patient.

Neuroradiological findings in Alagille syndrome

Alagille syndrome (ALGS) is a multisystemic disease caused by mutations in genes of Notch pathway, which regulates embryonic cell differentiation and angiogenesis. Clinically, ALGS is characterized by cholestasis, cardiac defects, characteristic facial features, skeletal and ophthalmologic abnormalities. The aim of this review is to illustrate neuroradiological findings in ALGS, which are less well-known and prevalent, including cerebrovascular anomalies (such as aneurysms, dolichoectasia, Moyamoya syndrome and venous peculiarities), Chiari 1 malformation, craniosynostosis, intracranial hypertension, and vertebral anomalies (namely butterfly vertebra, hemivertebra, and craniocervical junction anomalies). Rarer cerebral midline malformations and temporal bone anomalies have also been described.

Congenital absence of the bilateral internal carotid artery: a review of the associated (ab)normalities from a newborn status to the eighth decade of life

PURPOSE

Due to the fact that the internal carotid artery (ICA) is responsible for nourishing two thirds of the brain volume, our aim was to inspect the morphofunctional consequences of the bilateral lack of this artery.

METHODS

In order to examine this condition, we referred to both the library archive of our Faculty of Medicine and electronic databases of anatomical and clinical reports that included the following keywords: "absence," "aplasia," or "agenesis" in combination with "internal carotid artery," "common carotid artery," or only "carotid artery."

RESULT

We found 60 recorded cases of the bilateral ICA absence in the subjects of newborn status to the eighth decade of life, which had been discovered in 20 countries. The following ten parameters were described: the embryological base, terminology, history, incidence, general data, differential diagnosis, collateral circulation, the associated vascular aplasia and/or other variants, pathophysiology, and the importance in praxis.

CONCLUSION

This review noted all the cases of the bilateral ICA aplasia published for the past 104 years. Although there were 11.6% of cases of the associated cerebral aneurysms and 1-4 cases of 16 other diseases, approximately one quarter of the cases was without any pathology.

Right Aortic Arch Associated with Left Internal Carotid Artery Agenesis

We report the rare case of a right aortic arch associated with agenesis of the left internal carotid artery. A 75-year-old woman with a medical history of tetralogy of Fallot presented with dizziness. Magnetic resonance angiography revealed agenesis of the left internal carotid artery in addition to a previously diagnosed right aortic arch. The left common carotid artery was present, but it was thin. Computed tomography showed the absence of the left carotid canal. The left anterior cerebral artery was fed via the anterior communicating artery. The left middle cerebral artery was fed via a thickened posterior communicating artery originating from the left posterior cerebral artery. Although a right aortic arch and agenesis of the internal carotid artery are both very rare, association of the two conditions may occur. Both anomalies depend on the abnormal regression of the dorsal aorta during embryonic development. In such a situation, the presence of other anomalies in the cardiac or central nervous system should be taken into consideration.

Congenital absence of internal carotid artery with intercavernous anastomosis: Case report and systematic review of the literature

The absence of an internal carotid artery is a rare congenital anomaly. In the absence of the internal carotid artery, collateral circulations develop through the circle of Willis, persistent embryonic arteries or transcranial collaterals of the external carotid artery. Six pathways of collateral circulation have been described. Intercavernous anastomosis is between cavernous segments of the bilateral internal carotid arteries and is rarely seen. Patients with an absence of the internal carotid artery can be completely asymptomatic. However, these patients can present with subarachnoid hemorrhage or stroke accompanying cerebral aneurysm or abnormal collateral. We combined our case with 33 previous publications to form a retrospective series including 35 cases of unilateral internal carotid artery agenesis with intercavernous anastomosis.

PHACE syndrome is associated with intracranial cavernous malformations

INTRODUCTION

PHACE syndrome is a neurocutaneous disorder involving large facial hemangiomas in association with posterior fossa abnormalities, cerebral arterial anomalies, cardiac defects, and eye abnormalities. A recent consensus statement has delineated criteria necessary for the diagnosis of PHACE syndrome. Extracutaneous manifestations of PHACE syndrome predominately affect the cerebrovascular system. To date, there are no reports of cerebral cavernous malformations (CCMs) in children with PHACE syndrome.

METHODS

We reviewed the charts of children admitted to the Children''s Hospital of Pittsburgh who met criteria for PHACE syndrome, and evaluated neuroimaging for cerebrovascular abnormalities, including the finding of CCMs.

RESULTS

Six children met criteria for PHACE syndrome at our institution over a 10-year period. All children were female. All children had cerebrovascular abnormalities sufficient to meet major criteria for diagnosis. Four children (66.7 %) were found incidentally to have CCMs; all lesions measured less than 5 mm at the time of diagnosis and were asymptomatic.

CONCLUSION

At present, CCMs are not listed among the diagnostic criteria for PHACE syndrome, and they have not previously been reported in association with PHACE syndrome. Hypoxic injury in utero may be the common denominator in the pathogenesis of many of the abnormalities already accepted in the criteria for PHACE syndrome and the formation of CCMs. In the setting of PHACE syndrome, we encourage clinicians to evaluate children for CCMs, which are readily apparent on the already-recommended screening MRIs.

Tetralogy of Fallot and anomalous origin of the left pulmonary artery from the ascending aorta associated with absent right internal carotid artery

Anomalous origin of the left pulmonary artery from the ascending aorta is a rare cardiac malformation more commonly described with tetralogy of Fallot (TOF). The association of absent right carotid artery with TOF and anomalous left pulmonary artery from the ascending aorta has been rarely reported in the past. This case highlights the need for careful evaluation of the aortic arch and head vessels anatomy in patients with TOF because of the potential neurologic complications after surgery.

Gangliocapsular Bleed with Ipsilateral Internal Carotid Artery Aplasia

Background

Agenesis requires an extensive work-up as a number of associated other vascular and nonvascular anomalies can be expected. In this scenario, an associated ipsilateral basal ganglia bleeding with subarachnoid haemorrhage with no aetiology is uncommon. We present such a case of moderate ipsilateral ganglio-capsular bleed of unknown cause with associate aortic arch vessel anomaly.

Case Report

A 45-year-old diabetic man of Indian origin with complaints of a sudden onset of giddiness, left-sided weakness and slurring of speech. Motor system examination revealed power of grade 2. Computed tomography scan revealed a moderate bleeding in the basal ganglia and the right temporo-parietal lobe. Angiography revealed unilateral aplasia of the internal carotid artery.

Patient improved symptomatically with a motor system power of grade 4 after hematoma evacuation and treatment with antibiotics, anti-edema measures and neuroprotective drugs.

Conclusions

Developmental anomalies of the carotid and aortic arch with intracranial bleeding is a rare occurrence and any arterial anomaly requires extensive evaluation.

Agenesis of the internal carotid artery with paraclinoid-supraclinoid anastomosis and basilar artery-posterior communicating artery anastomosis diagnosed by magnetic resonance angiography

The several types of agenesis of the internal carotid artery (ICA) are classified based on the aplastic segment of the ICA and types of collateral circulation. On magnetic resonance angiography, we incidentally found an extremely rare case in which the patient had 2 types of collateral circulation-anastomosis between the paraclinoid and supraclinoid segments of the contralateral ICA and anastomosis between the tip of the basilar artery and the posterior communicating artery. This is the first report of a case of ICA agenesis with 2 such types of collateral circulation.

Goldenhar syndrome associated with contralateral agenesis of the internal carotid artery

Congenital absence of the internal carotid artery (ICA) is an extremely rare vascular anomaly. Aplasia and displacement of the horizontal portion of the petrous carotid artery have been described in a patient with mandibulofacial dysostosis. To the best of our knowledge, the association between Goldenhar syndrome and ipsilateral ICA agenesis has emerged only in one case documented in the medical literature to date. We describe here a case that illustrates the association of Goldenhar syndrome with contralateral agenesis of the ICA incidentally detected on brain magnetic resonance imaging and subsequently confirmed on magnetic resonance angiography and high resolution computed tomography.