Vascular lesions of the pediatric orbit: A radiological walkthrough

Vascular anomalies of the pediatric orbit represent a heterogeneous group that include both vascular tumors and vascular malformations. The disorder may initially be silent and then associated with symptoms and/or function damage, depending on the type of vascular anomaly and its extension. Vascular tumors include benign, locally aggressive (or borderline) and malignant forms while vascular malformations are divided into "simple", "combined" and syndromic, or "low flow" or "high flow". Both entities can arise in isolation or as part of syndromes. In this review, we describe the imaging findings of the vascular lesions of the orbit in the pediatric population, which are key to obtain a correct diagnosis and to guide the appropriate treatment in the light of the new genetic and molecular discoveries, and the role of the radiologist in their multidisciplinary management. We will also touch upon the main syndromes associated with orbital vascular abnormalities.

Multiple and mirror intracranial aneurysms: study of prevalence and associated risk factors

OBJECTIVE

Multiple intracranial aneurysms (MIA) account for 30% of all intracranial aneurysms, while mirror aneurysms, a subgroup of MIA, are present in 5% of all patients with cerebral aneurysms. We investigated the risk factors associated with the presence of multiple and mirror intracranial aneurysms.

METHODS

1404 patients, 314 males (22.4%) and 1090 female (77.6%) were enrolled for this study. Diagnosis was performed with a digital subtraction angiography (DSA). Multiplicity was defined as the presence of two or more aneurysms and mirror aneurysms as one pair of aneurysms involving bilateral corresponding arteries. Patients were followed-up from September 2009 till August 2018. Individuals' characteristics such as sex, age, smoking, hypertension and use of contraceptives were evaluated.

RESULTS

Five hundred and twelve patients (36.4%) were diagnosed with MIA, approximately 4%/year. We observed 203 pairs of mirror aneurysms, accounting for 406 aneurysms (13% of the population). There was an increased frequency of females with multiple (p < 0.001, OR = 1.883, 95% CI = 1.386-2.560) and mirror aneurysms (p < 0.001, OR = 2.828, 95% CI = 1.725-4.636). Smoking was associated with multiplicity (p< 0.001, OR = 1.458, 95% CI = 1.160-1.833), as well as advanced age (p < 0.001, OR = 1.938, 95% CI = 1.438-2.611), but there was no significant relation with presence of mirror aneurysms. We observed higher frequency of baby aneurysms (<3mm) in the group of patients with MIA, while giant aneurysms (>25 mm) were most found in patients with only one aneurysm (p < 0.001). No differences between patients who used contraceptives against patients who did not use were found (p = 0.600).

CONCLUSIONS

Gender and smoking, known risk factors to the development of a single intracranial aneurysm, are proportionally increased in patients with MIA. Hypertension and oral contraceptives were not associated with multiplicity.

A Rare Case Report of Multiple Intracranial Aneurysms with Factor VII Deficiency

Pathogenesis of intracranial aneurysms is multi-factorial. Origin of aneurysm may be acquired or genetic, and there may be more than one aneurysm simultaneously, or there may be the formation of a new aneurysm after treatment of previous one. Collagen vascular disorders, neurofibromatosis, polycystic kidney disease, and so many other disorders are associated with multiple intracranial aneurysms. As Factor VII deficiency is also genetic in origin, there might be a correlation between deficiency of the same with multiple intracranial aneurysms. Only one such case is reported in the literature and we are reporting such a rare case having a similar association.

Flow diverter for endovascular treatment of intracranial mirror segment internal carotid artery aneurysms

BACKGROUND

To evaluate the feasibility and efficacy of the pipeline embolization device in the treatment of unruptured intracranial mirror segment aneurysms.

METHODS

Out of a total of 338 subjects, 14 were identified harboring a total of 32 internal carotid artery mirror segment aneurysms that were treated with the pipeline embolization device and were consecutively enrolled into our study. We collected data on patient demographics, modified Rankin scale (mRS) at admission, aneurysm characteristics, clinical outcome at discharge, 3-9 and at 12-18 months as well as angiography results at follow-up.

RESULTS

Patients' mean age was 52.9 years; baseline mRS was 0 in all subjects. Pipeline embolization device placement was successful in all cases. Post-treatment mRS remained 0 in 13/14 patients. One patient experienced a small intraparenchymal hemorrhage and subarachnoid hemorrhage, associated with a frontoparietal infarction resulting in right upper extremity weakness and aphasia (post-treatment mRS 3). His mRS evaluation remained stable at the 3-9-month follow-up. Three to 9-month follow-up angiography (13/14 subjects) showed complete aneurysm occlusion in 24/30 aneurysms (80%), near complete and partial occlusion in three of 30 (10%) aneurysms each. At the 9-month follow-up, one patient experienced a complete occlusion of the anterior temporal artery branch but did not present with any clinical deficits. No mRS changes were encountered over a median 6-month follow-up period. Mid-term follow-up angiography (12-18 months) available in eight of 14 subjects showed complete aneurysm occlusion in all patients. Mild intimal hyperplasia was observed in one patient.

CONCLUSIONS

Flow diversion technology can be used for the treatment of unruptured mirror segment aneurysms in selected patients.

Cerebrofacial arteriovenous metameric syndrome (CAMS): a spectrum disorder of craniofacial vascular malformations

Cerebrofacial arteriovenous metameric syndrome (CAMS) is a recent classification of vascular malformations that encompasses a spectrum of phenotypic expression involving arteriovenous malformations (AVMs) of the cerebral, orbital, and facial region. Recognizing the embryologic basis of CAMS is important for diagnosing other AVMs along the same metameric level. Visual loss is the most common presentation prompting ophthalmologic evaluation followed by neuroimaging. We present two pediatric patients with ipsilateral optic nerve and chiasmal AVMs without cutaneous manifestations, characteristic of CAMS 2. The diagnosis of cerebral AVMs was made by magnetic resonance imaging of the brain and confirmed with cerebral angiography. High-resolution flat-panel computed tomography was performed in one patient and was useful to demonstrate the intraneural invasion of the optic nerve by the AVM.

Clinical characteristics and preferential location of intracranial mirror aneurysms: a comparison with non-mirror multiple and single aneurysms

INTRODUCTION

The purpose of our study was to compare the clinical characteristics and preferential localization of aneurysms in three patient groups: single aneurysm, non-mirror multiple aneurysms, and mirror aneurysms.

METHODS

We retrospectively reviewed the clinical and radiological data of 2223 consecutive patients harboring 3068 aneurysms registered at the Toronto Western Hospital between May 1994 and November 2010. The patients were divided into single, non-mirror multiple, or mirror aneurysm groups. Expected incidences of mirror aneurysms at each location were calculated on the basis of the single aneurysm incidences at each location.

RESULTS

Patients with mirror aneurysms (n = 197) did not differ from patients with non-mirror multiple aneurysms (n = 392) in having female predominance (81.7 vs. 76.3 %) or a family history of intracranial aneurysm (20.5 vs. 17.6 %). When compared with expected incidences at each location, mirror aneurysms were more frequently found at the cavernous internal carotid artery (30 vs. 11.5 %) (p < 0.0001). Mirror aneurysms involving the posterior circulation were less frequent (6.7 %) than aneurysms in the single (19.6 %) or non-mirror multiple aneurysm groups (18.9 %) (p < 0.05).

CONCLUSION

Patients with mirror aneurysms had similar clinical characteristics to non-mirror multiple aneurysm patients. Mirror aneurysms showed a predilection for the cavernous carotid artery, whereas they were comparatively rare in the posterior circulation.

Echocardiographic evidence of innate aortopathy in the human intracranial aneurysm

BACKGROUND

Intracranial aneurysm (IA) is significantly more prevalent in patients with coarctation of the aorta or bicuspid aortic valve than in the general population, suggesting a common pathophysiology connecting IA and aortopathy. Here, we analyzed echocardiographic aortic root dimension (ARD) in patients with IA to confirm this possibility.

METHODS

From January 2008 to December 2010, 260 consecutive patients with IA who were admitted to our institution for coil embolization or for acute stroke management and who also underwent echocardiography were enrolled. We hypothesized that patients with large, ruptured, or multiple IAs are more likely to harbor co-prevalent aortopathy as measured by ARD compared to patients with small, isolated, unruptured IAs. Eccentric group was defined as patients aged <55 years with at least one ruptured aneurysm, an aneurysm ≥7 mm in size, or multiple aneurysms; the remainder was classified into a non-eccentric group. Clinical, angiographic, and echocardiographic findings of the two groups were compared.

RESULTS

ARD was significantly larger in the eccentric group than in the non-eccentric group (P = 0.049), and the difference was confirmed by multivariable analysis (P = 0.02). Subgroup analysis of patients aged <55 years showed similar result for ARD (P = 0.03), whereas hypertension was more associated with the non-eccentric group (P = 0.01). In addition, height was inversely related to aneurysm size after adjustment for age, sex, weight, ARD, smoking status, and number of aneurysms (P = 0.004).

CONCLUSIONS

A certain group of IA patients share a common intrinsic wall defect with aortopathy. Shared neural crest cell origin may give rise to this phenomenon.

Suggested connections between risk factors of intracranial aneurysms: a review

The purpose of this article is to review studies of aneurysm risk factors and the suggested hypotheses that connect the different risk factors and the underlying mechanisms governing the aneurysm natural history. The result of this work suggests that at the center of aneurysm evolution there is a cycle of wall degeneration and weakening in response to changing hemodynamic loading and biomechanic stress. This progressive wall degradation drives the geometrical evolution of the aneurysm until it stabilizes or ruptures. Risk factors such as location, genetics, smoking, co-morbidities, and hypertension seem to affect different components of this cycle. However, details of these interactions or their relative importance are still not clearly understood.

Diagnostic characteristics and management of intracranial aneurysms in children

Childhood aneurysms have special characteristics different from adults' aneurysms. Their features were found to significantly differ from aneurysms in adults especially in their gender prevalence, location, morphology and underlying etiology. Treatment options include both surgical and endovascular methods. Whenever possible, endovascular treatment for pediatric aneurysms is the recommended approach, since it offers both reconstructive and deconstructive techniques, durable results and better clinical outcome.

Association of cervical internal carotid artery aneurysm with ipsilateral vertebrobasilar aneurysm in two children: a segmental entity?

INTRODUCTION

A combination of cervical and intradural aneurysm in children in the absence of systemic disorders has previously not been reported.

CASE REPORT

We report two boys with an identical combination of fusiform cervical internal carotid aneurysm and ipsilaterally located vertebrobasilar aneurysm. They had no history of trauma, they did not display any personal or familial signs of systemic disease, and the testing for collagen disease was negative. The location and appearance of the aneurysms and the identical anatomical disposition in the patients indicated a non-randomly distributed segmental vulnerability.

CONCLUSION

The cases demonstrate primary morphological signs of a developmental error being expressed in two seemingly separate segments but linked by the hypoglossal artery. It suggests a segmental error related to this embryonic vessel. They also show that few phenotypes are specific for a genotypic disorder and highlight the importance of analysing different etiologies for aneurysm formation and anatomical disposition when taking treatment strategy decisions.

Multiple mirror-like intracranial aneurysms. Report of a case and review of the literature

While multiple intracranial arterial aneurysms occur in 26.4% of patients with aneurysms, in our practice bilateral mirror-like aneurysms are encountered in 9.4% of patients. Multiple mirror aneurysms in the same patient are exceedingly rare. We report a case of mirror-like middle cerebral artery aneurysms associated with mirror-like posterior inferior cerebellar arteries aneurysms and discuss their significance. Although an exceptional finding, multiple mirror-like aneurysms may shed light on the vulnerability of different arterial segments to specific diseases.

Spontaneous mirror dissections of cervicocephalic arteries. Pathomechanical considerations

SUMMARY

While so-called twin or mirror aneurysms constitute an established subgroup of multiple aneurysms, simultaneous spontaneous mirror dissections of cervicocephalic artery have not yet been reported as a particular entity. Among the patients treated at our institution since 1989, we identified 74 patients with spontaneous, nontraumatic dissections. Six of these cases presented with simultaneous bilateral dissections and four of the six patients had mirror dissections. Acute or chronic headache was present in all four cases. Additional clinical presentations consisted of impaired consciousness, cranial nerve palsy, and tinnitus. Angiography revealed irregular stenosis, dilatation or aneurysms located in the cervical ICA (internal carotid artery), VA (vertebral artery), or MCA (middle cerebral artery) without evident location bias. Although mirror dissections seems to be an exceptional finding, they may shed light on the vulnerability of different arterial segments to specific diseases. Similar to arterial aneurysm formation, pathogenesis of mirror dissection may involve an underlying "shared defect" in the endothelial cells, since these cells demonstrate a bilateral distribution during embryological development. This particular distribution therefore also provides a chronicle trail of the first trigger striking during embryonic development and demonstrates the segmental vulnerability to highly specific triggers.

"Mirror" aneurysms involving the bilateral distal posterior cerebral artery. A case report of endovascular treatment and literature review

SUMMARY

We report the case of patient with bilateral and symmetrical aneurysms, mirror image, of the distal posterior cerebral artery (PCA) who presented with subarachnoid haemorrhage. The aneurysms were treated by endovascular approach using Guglielmi detachable coils (GDCs). A review of the pathophysiology, clinical manifestations and management of mirror aneurysms is presented and discussed.

A comparison of risk factors in the etiology of mirror and nonmirror multiple intracranial aneurysms

BACKGROUND

Pure mirror intracranial aneurysms represent a subgroup of multiple aneurysm patients where a congenital predisposition may play a major etiologic role. The aim of this study was to compare the pattern of prevalence of known risk factors for aneurysm disease between pure mirror and pure nonmirror multiple aneurysm populations.

METHODS

Clinical records of all patients with multiple intracranial aneurysms admitted to our institution between January 1985 and September 2001 were reviewed. Age, localization of aneurysms, gender, and history of cigarette smoking or hypertension were noted and compared using Fisher's exact test and logistic regression analysis.

RESULTS

There were 33 patients presented with pure mirror aneurysms (MirAn) and 49 with nonmirror multiple aneurysms (nMirAn). Average age of rupture occurred in the 5th decade in both groups. Female:male ratio was 3.1:1 in MirAn; 2.1:1 in nMirAn. In MirAn patients younger than 40 years it was 1:1. Smoking was the most prevalent risk factor in nMirAn (59.2%). In MirAn this was true only for patients in the 5th or 6th decades (65%), and hypertension was the most prevalent risk factor over that age (62.5%). A total of 80% of mirror aneurysm patients under 40 years had no known extrinsic risk factor, compared with 20% in nMirAn (p < 0.05).

CONCLUSIONS

Differences in the relative prevalence of risk factors between both groups supports the hypothesis of a different etiologic process occurring in mirror aneurysm disease. Early rupture in patients with no extrinsic risk factors lends support to the role of a congenital predisposition over degenerative causes in these patients.

5-year Angiographic and Clinical Follow-up of Coil-embolised Intradural Saccular Aneurysms. A Single Center Experience

SUMMARY

The purpose of the paper is the follow-up of embolised intradural saccular Arterial Aneurysms (AA), excluding giant, dissecting, inflammatory, fusiform or AA associated to BVAM. Since its introduction in 1991, the Guglielmi Detachable Coil has offered protection against aneurysmal rebleeding in the critical few days and months after SAH regardless of the grade. A number of questions remain: is complete angiographic obliteration necessary at first embolisation? What duration of clinical / angiographic follow-up (FU) is required to ensure the risk of haemorrhage has been eliminated? What is the long-term protection against rebleeding? One hundred and two patients with 160 intradural saccular AA embolised before april 1997 were selected for this study. They had at least 5-yrs clinical FU, of which 22 patients had a mid- term (3 years) and 45 patients had a 5-year or more angiographic FU (mean 67,7 months per patient). Twenty-eight embolised AAs with 100% occlusion at 1 year, remained unchanged on the 5-year angiograms. A further 14 patients with complete occlusion at 1 year showed persisting complete occlusion on angiogram at 3-years FU, which in our series means that complete occlusion after the first year post-embolisation implies that the aneurysm will remain completely occluded. All secondary spontaneous thromboses (27.6% of cases), occurred during the first year pos- embolisation. In six patients with subtotal or partial occlusion no change was seen for three consecutive years of FU; none showed later change at 5-year angiography. Below 80% occlusion our series does not provide enough information but we consider the situation instable. No mortality related to the procedure was observed in the unruptured AA group.No bleeding or re-bleeding has occurred since the beginning of our experience (1993) in saccular AA treated by GDC-Coil. Coil-embolisation of properly selected patients is effective in protecting against bleeding or re-bleeding at short and long-term with stable morphological results provided a strict follow-up control is established at short term.

Aneurysm and Subarachnoid Haemorrhage

Although CT angiography is more and more widely used as diagnostic tool in SAH, DSA remains a useful technique. Indeed DSA is mandatory in patients with SAH and negative angio-CT, and in all other doubtful cases. Angiography is also necessary in order to perform an endovascular treatment. Sometimes, after a SAH a first angiogram may be normal due to spasm, haematoma or in case of a real perimesencephalic haemorrhage. The need for a second angiogram is discussed. Finally some aspects concerning the aneurysmal growth and rupture are also discussed.

A case of multiple intracranial aneurysms with unruptured associated aneurysms and newly developed ruptured aneurysm

SUMMARY

We report a case of mirror aneurysms at the middle cerebral artery bifurcation with rupture on the left side. After six years, the patient had subarachnoid haemorrhage from a de novo aneurysm which developed separate from but adjacent to the already present aneurysm on the right side. The mechanism of development of multiple aneurysms, especially of the mirror-image type cannot be explained based only on haemodynamic factors and congenital segmental arterial vulnerability which is generalised than focal is highly likely. The sequence of development of aneurysms in this patient along with existing knowledge regarding rupture of aneurysms in conditions like polycystic kidney disease raise questions about the current trend of treating all patients with coincidental, unruptured aneurysms as they may never bleed from such aneurysms but could still be at risk of SAH from newly developing aneurysms.

Trifocal monomyelomeric spinal cord arteriovenous fistulae in a seven-year-old boy

SUMMARY

We describe a rare case of multiple arteriovenous fistulae of the spinal cord (SCAVF) in the same myelomer in a five-year-old boy. This case report consists of a trifocal SCAVF at the Th12 myelomeric level without communication between the three different fistulae. Two AVF were located posteriorly, bilateraly, in the spinal cord, fed by left and right posterior radiculopial arteries and one anteriorly in the anterior spinal axis. The venous drainage was independent for each lesion. The patient presents associated lesions characterized by cutaneous stain and inferior limb asymmetry. A metameric distribution is the explanation for the multiplicity of these lesions in a syndromic association related to Cobb syndrome. The patient was treated by transarterial embolization using glue with occlusion of the three different fistulae. The patient achieved a good improvement in neurological status.

Multifocal cerebral fusiform aneurysms in children with immune deficiencies report of four cases

SUMMARY

We describe three children infected by the human immunodeficiency virus (HIV 1), and one child suffering from familial mucocutaneous candidiasis, who all had multiple, fusiform subarachnoid intracranial aneurysms. Because infectious causative agents were never detected at the level of the lesions, a classical "mycotic" origin of these aneurysms seemed unlikely. Despite the fact that these aneurysms have the same angiographic appearance, they have different etiologies (immune and infectious). These data open the discussion on the reciprocal role of an infectious or immune initial trigger acting on a vascular (endothelial) target. The specificities of the target in terms of location and response enhance specific topographic characteristics (phenotypes) of the cerebral vasculature.

Risk factors for the formation of multiple intracranial aneurysms

Object. Several factors are known to increase the risk of subarachnoid hemorrhage (SAH) and spontaneous intracerebral hematoma. However, information on the roles of these same factors in the formation of multiple aneurysms is less well defined. The purpose of this study was to examine factors associated with an increased risk of multiple aneurysm formation.

Methods. A retrospective review of the medical records of all patients with a diagnosis of SAH and intracranial aneurysms who were admitted to a single institution between 1985 and 1997 was undertaken. The authors examined associations between risk factors (patient age and sex, menopausal state of female patients, hypertension, cigarette smoking, alcohol consumption, history of cardiovascular disease or diabetes mellitus, and family history of cerebrovascular disease) and the presence of multiple aneurysms by using the Fisher exact test and logistic regression analysis. Of 400 patients admitted with a diagnosis of cerebral aneurysms, 392 were included in the study (287 women and 105 men). Two hundred eighty-four patients harbored a single aneurysm and 108 harbored multiple aneurysms (2 aneurysms in 68 patients, three aneurysms in 22 patients, four aneurysms in 13 patients, and five aneurysms in five patients).

Conclusions. Statistical analysis revealed that, as opposed to the occurrence of a single aneurysm, there was a significant association between the presence of multiple aneurysms and hypertension (p < 0.001), cigarette smoking (p < 0.001), family history of cerebrovascular disease (p < 0.001), female sex (p < 0.001), and postmenopausal state in female patients (p < 0.001).

Endovascular Management of Intradural Berry Aneurysms. Review of 203 Consecutive Patients Managed between 1993 and 1998 Morphological and Clinical Results at Mid-Term Follow-up

SUMMARY

Endovascular management of intracranial arterial aneurysms (AA) is well described and performed by many teams. The aim of this work is to review a series of consecutive cases treated in our institution and to compare to the data available in the literature. 225 AA were seen in Bicêtre between 1993 and 1998 in 203 patients. 201 of them (in 180 patients) were treated by our group. The endovascular treatment, its indications, results and complications have been reviewed and studied. The clinical follow-up of the patients has been evaluated. A female dominance was noted (64.5%) with a mean age of patients of 44.3 years. 65.6% of patients were treated in the acute phase after intracranial haemorrhage, 72% of them being Hunt and Hess grade 1 or 2. Most of these AA (73.6%) were located in the anterior circulation. In 86.1% of cases the AA was smaller than 10 mm. 85.6% of the AA needed only one session of endovascular therapy. No mortality occurred in the group of unruptured AA. Overall management mortality was 11% in ruptured AA (3.5% in HH1-2, 30.3% in HH3-5).Technical or transient complications occured in 11.6% of cases, but permanent morbidity was seen in 3.1% of cases. Control angiograms were performed 3 months and one year after therapy. In doubtful cases a control at 6 months was also performed. 100% occlusion rate was noted in 60.8% of cases; 22.8% of AA were occluded between 90-99%, and 13.3% between 80-90%. Only 3.1% of AA had an occlusion rate of less than 80%. One patient with a ruptured basilar tip AA which was partially coiled regrew and rebled three months after. The patient declined the recommended complementary surgery. Clinical follow up of patients with ruptured AA treated by embolisation shows satisfactory results with 8.5% of GOS 1-2, 3.4% of GOS 3-4, and 11% of GOS 5 (mortality). Overpacking of the AA may not be necessary to protect patients from (re)bleeds over time. The related technical risks and increased costs of dense overpacking do not seem justified. Secondary thrombosis of the ruptured AA after coiling is more often seen than coil compaction. Analysis of the AA architecture and recognition of false aneurysms are mandatory in order to obtain good clinico-morphological logical results.