Venous angiomas: plain and contrast-enhanced MRI and MR angiography

Angiomi venosi o «anomalie di sviluppo venoso»

Sono stati studiati con RM 29 pazienti con anomalie di drenaggio venoso in condizio-ni basali e dopo Gadolinio-DTPA; 24 sono stati sottoposti anche ad angio-RM. Nella valutazione dei risultati è stato assegnato un punteggio: 0 quando l'anomalia non era evidenziata; 1 per la rappresentazione del solo collettore; 2 per la dimostrazione del collettore e delle vene midollari; 3 per la dimostrazione del collettore, delle vene midollari e del tipo di drenaggio. È stata inoltre considerata la presenza di eventuali angiomi cavernosi associati e l'eventuale correlazione con la sintomatologia.

Le sequenze SE Tl pesate dopo Gadolinio-DTPA in doppia dose sono risultate quelle con maggiore accuratezza diagnostica (score 77) sia rispetto alle sequenze basali (T1 score 12, T2 score 31) sia nei 24 pazienti sottoposti anche ad angio-RM (SE T1 dopo Gadolinio score 66, angio-RM score 61). L'angio-RM è risultata utile nell' evidenziare il tipo di drenaggio.

In 5 casi l'anomalia di sviluppo venoso era associata ad un angioma cavernoso, in 4 casi le due malformazioni erano in stretto rapporto; solo in due casi però l'angioma cavernoso presentava il tipico aspetto a «pop-corn». In un solo paziente l'anomalia venosa si è presentata come evento emorragico, mentre in un altro caso era in stretto rapporto con un'area di basso segnale in T1 e T2, esito di una pregressa emorragia.

Nel 34% i pazienti hanno presentato epilessia senza però una costante correlazione tra sede dell'ano-malia venosa e sede dell'anomalia elettroencefalografica.

Magnetic resonance angiography using fresh blood imaging in oral and maxillofacial regions

The present paper provides general dentists with an introduction to the clinical applications and significance of magnetic resonance angiography (MRA) in the oral and maxillofacial regions. Specifically, the method and characteristics of MRA are first explained using the relevant MR sequences. Next, clinical applications to the oral and maxillofacial regions, such as identification of hemangiomas and surrounding vessels by MRA, are discussed. Moreover, the clinical significance of MRA for other regions is presented to elucidate future clinical applications of MRA in the oral and maxillofacial regions.

Cortical vessel imaging and visualization for image guided depth electrode insertion

To avoid intracranial hemorrhage during minimally invasive depth electrode insertion without craniotomy for epilepsy surgery, precise in vivo imaging of cortical vessel and relevant rendering methods are critical, and should be used in preoperative planning. In this study, a non-invasive phase contrast MR angiography (PC-MRA) method was chosen for cortical vessel imaging. After image pre-processing (registration and segmentation), three visualization methods were implemented to optimize the vessel imaging and brain tissue rendering for surgical planning. The processed results were evaluated by comparing with intraoperative photographs. The results showed occurrences of missing vessels between imaging and photos (18.3%, 6 cases), but these could be compensated by realistic sulci visualization methods. The results showed 3D texture mapping to be the most suitable cortex visualization method for use in surgical navigation. Based on the methods and evaluations, a new surgical planning system and criteria of usage were developed with input from the surgeons' experience using the prototype system. This system could greatly help reduce the risk of the intracranial hemorrhage during electrode insertion and also avoid potential risks caused by contrast agent injections for contrast enhanced MRA or CTA.

Noninvasive identification of peripheral vessels of oral and maxillofacial regions by using electrocardiography-triggered three-dimensional fast asymmetric spin-echo sequences

OBJECTIVES

The aim of this study was to evaluate the 3-dimensional images of thinner main peripheral vessels in oral and maxillofacial regions made without contrast medium by using a new technique, fresh blood imaging (FBI). A second objective was to discern arteries from veins by using the combination of FBI with the subtraction technique.

STUDY DESIGN

Images from FBI were compared with those from 3-dimensional phase-contrast magnetic resonance angiography (MRA) of blood vessels in 20 healthy subjects. All images were scored for visualization and image quality of the main blood vessels. In addition, appropriate flow-spoiled gradient pulses were applied to differentiate arteries from veins in the peripheral vasculature using a combination of FBI sequences and subtraction between systole- and diastole-triggered images.

RESULTS

The scores of MRA using FBI for the visualization of thin blood vessels were significantly better than those using phase contrast, whereas scores for the visualization of main blood vessels were equal. Additionally, we succeeded in our initial attempt to differentiate arteries from veins with a reasonable acquisition time.

CONCLUSIONS

Our initial experience shows that FBI could be a useful method to identify 3-dimensional vasculature and to differentiate arteries from veins among thinner peripheral vessels in the oral and maxillofacial regions without using contrast medium.

Cavernous angiomas of the brain stem and spinal cord

This article reviews the pathology, clinical course and management of cavernous angiomas in the brain stem and spinal cord. Both lesions have been diagnosed with increasing frequency as a result of magnetic resonance image scanning. Brain stem lesions tend to present dramatically; their treatment remains microsurgical excision despite some studies that have looked at the use of radiosurgery. Spinal lesions are either extra-, or more commonly, intramedullary. Intramedullary cavernomas present with a wide spectrum of symptoms ranging from acute haematomyelia to presentations that mimic demylelinating conditions; extramedullary cavernous angiomas tend to produce radicular symptoms or subarachnoid haemorrhage. Both are treated by microsurgical excision.

Simultaneous occurrence of subarachnoid hemorrhage due to ruptured aneurysm and remote brainstem hematoma--case report

A 48-year-old woman presented with simultaneous aneurysmal subarachnoid hemorrhage (SAH) and remote intracerebral hemorrhage manifesting as sudden onset of severe headache, left hemiparesis, and diplopia. Emergent computed tomography revealed localized SAH in the interpeduncular cistern, and a remote brainstem hematoma in the right dorsolateral tegment. Neuroimaging found no signs of vascular anomaly in the brainstem. The aneurysm at the basilar artery and superior cerebellar artery bifurcation was successfully embolized using coils. Her postoperative neurological status was improved except for slight diplopia. The causes of this extremely rare case of simultaneous occurrence of aneurysmal SAH and remote brainstem hematoma in the dorsolateral tegment remain obscure.

Parenchymal abnormalities associated with developmental venous anomalies

INTRODUCTION

To report a retrospective series of 84 cerebral developmental venous anomalies (DVAs), focusing on associated parenchymal abnormalities within the drainage territory of the DVA.

METHODS

DVAs were identified during routine diagnostic radiological work-up based on magnetic resonance imaging (MRI) (60 cases), computed tomography (CT) (62 cases) or both (36 cases). Regional parenchymal modifications within the drainage territory of the DVA, such as cortical or subcortical atrophy, white matter density or signal alterations, dystrophic calcifications, presence of haemorrhage or a cavernous-like vascular malformation (CVM), were noted. A stenosis of the collecting vein of the DVA was also sought for.

RESULTS

Brain abnormalities within the drainage territory of a DVA were encountered in 65.4% of the cases. Locoregional brain atrophy occurred in 29.7% of the cases, followed by white matter lesions in 28.3% of MRI investigations and 19.3% of CT investigations, CVMs in 13.3% of MRI investigations and dystrophic calcification in 9.6% of CT investigations. An intracranial haemorrhage possibly related to a DVA occurred in 2.4% cases, and a stenosis on the collecting vein was documented in 13.1% of cases. Parenchymal abnormalities were identified for all DVA sizes.

CONCLUSION

Brain parenchymal abnormalities were associated with DVAs in close to two thirds of the cases evaluated. These abnormalities are thought to occur secondarily, likely during post-natal life, as a result of chronic venous hypertension. Outflow obstruction, progressive thickening of the walls of the DVA and their morphological organization into a venous convergence zone are thought to contribute to the development of venous hypertension in DVA.

Three-dimensional identification of hemangiomas and feeding arteries in the head and neck region using combined phase-contrast MR angiography and fast asymmetric spin-echo sequences

OBJECTIVE

To evaluate a proposed technique for the 3-dimensional (3D) detection of hemangiomas, including vascular malformation and their feeding arteries, in the head and neck. The new technique combines phase-contrast magnetic resonance angiography (PCMRA) without contrast medium and 3D fast asymmetric spin-echo (FASE) sequences.

METHODS

The technique was applied to 3 patients having hemangiomas in the head and neck region. In 1 patient the image obtained with the proposed technique was compared to that obtained by standard contrast angiography.

RESULTS

In all 3 patients, the 3D presence of the hemangiomas and the feeding arteries were well defined in images created by the proposed technique. Additionally, the characterization of the hemangioma's 3D structure and distribution of the feeding arteries coincided with those observed using contrast angiography in the case for which contrast angiography was also performed.

CONCLUSIONS

Preliminary experience shows that the proposed technique combining 3D-FASE and 3D-PCMRA is useful to visualize both the 3D structure of hemangiomas and to identify the 3D distribution of the feeding arteries without using contrast medium.

Neuroendoscopic Appearance of an Intraventricular Cavernous Angioma Blocking the Foramen of Monro-Case Report-

A 47-year-old woman presented with unilateral ventricular enlargement detected by magnetic resonance imaging during a medical checkup. Neuroendoscopic exploration identified a multilocular lesion in which dark red fluid formed a niveau near the right side of the foramen of Monro. The diagnosis was intraventricular cavernous angioma. Restricted flow of cerebrospinal fluid at the foramen of Monro was observed. Xanthochromia, which seemed to be due to previous bleeding, was observed at the fornix. When the neuroendoscope touched the angioma, the wall collapsed and bled. Endoscopic removal of the angioma was abandoned, and craniotomy and resection of the angioma were performed. No new neurological anomalies were observed after surgery. Preoperative diagnosis of intraventricular cavernous angioma is difficult based on neuroimaging. Neuroendoscopy is effective for diagnosis and the decision-making process regarding treatment.

Cerebral Cavernous Malformations Associated with Venous Anomalies: Surgical Considerations

OBJECTIVE:

Once thought to be rare entities, mixed cerebrovascular malformations with pathological features of more than one type of malformation within the same lesion are now being recognized with increasing frequency. Their identification generates several hypotheses about common pathogenesis or causation-evolution among different types of lesions and leads to controversial discussion on therapeutic strategies.

METHODS:

Fifteen patients drawn from a consecutive series of 58 patients harboring cavernous malformations (25.9%) were found to have an associated venous malformation (VM). Three (33.3%) of the first 9 patients, in whom the large draining vein of the VM had been left untouched at previous interventions, developed recurrent and/or de novo lesions.

RESULTS:

Histopathological analysis, interestingly, revealed that the new lesions were different in nature (three arteriovenous angiomas in two patients, a capillary telangiectasia in one patient). During extirpation of the new malformation, the draining vein of the VM in these three patients could be coagulated without any adverse events. Coagulation and dissection of the draining vein of the associated VM was performed in six more patients of our series, and this has prevented development of new lesions up to now.

CONCLUSION:

Our results are in favor of the hypothesis that the draining vein of a VM is the actual underlying abnormality of mixed vascular malformations. Causing flow disturbances and having the potential for hemorrhages, the VM seems to promote the development of new adjacent malformations. Thus, permanent cure of associated malformations might depend on the surgical treatment of the VM. We present a preliminary personal series and a thorough review of the literature.

Cerebral venous angioma of the pons complicated by nonhemorrhagic infarction

✓ The authors emphasize an unusual complication of venous angiomas in the brain: venous infarction. The patient in this case is a 32-year-old man who presented with a clinical history of headache followed by a worsening of his neurological status. Neuroimaging studies demonstrated a brain infarct in the posterior fossa, which was related to thrombosis of the draining vein of a cerebral venous angioma. A conservative treatment approach without anticoagulation therapy was followed and the patient completely recovered. Nonhemorragic venous infarction caused by thrombosis of a venous angioma is exceptional and only nine previous cases have been reported in the literature.

Surgical correction of symptomatic vertebral artery kinking

Two cases of repeated posterior fossa ischaemia are presented. Other sources of embolization, except middle part vertebral artery kinkings were excluded. Medical therapy failed in both cases. A simple surgical technique was employed--kink straightening and fixation. In both cases the surgery was simple, safe, yielding the desired effect.