Perfusion and blood pool scintigraphy for diagnosing soft-tissue arteriovenous malformations

Clinical Values of Whole-Body Blood Pool Scans and SPECT for Evaluation of Congenital Vascular Malformation

Purpose

This study examines the diagnostic potential of whole-body blood pool scintigraphy (WBBPS) using technetium-99 m-labeled red blood cells to detect congenital vascular malformations (CVMs). It aims to compare its efficacy with traditional imaging techniques such as magnetic resonance imaging (MRI) and ultrasonography (USG), emphasizing its potential advantages in terms of characterization of lesions and capacity for whole-body assessment.

Methods

The efficacy of WBBPS and single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging in diagnosing CVMs, comparing them with USG and MRI results, was evaluated in this retrospective study. Of the 38 patients, 21 were evaluated using these diagnostic methods, with CVMs classified according to the International Society for the Study of Vascular Anomalies guidelines. Also, this study aimed to elucidate the characteristics between WBBPS, SPECT/CT, USG, or MRI findings and their consistency with the final diagnosis.

Results

A total of 21 participants were included in this study, with an average age of 17.7 years old, with female predominance (57.1%). The most common diagnosis was vascular malformations (VMs) (71.4%), followed by combined vascular malformations (14.3%) and lymphatic malformations (9.5%). WBBPS demonstrated positive results in 95.2% of cases. Distinct imaging patterns for each condition were observed, with WBBPS being crucial in locating lesions.

Conclusion

The study findings suggested that WBBPS with SPECT/CT could be helpful in detecting occult VM lesions and ruling out a lymphatic malformation diagnosis. Thus, it can be employed in the evaluation of CVMs.

Venous malformation and haemangioma: differential diagnosis, diagnosis, natural history and consequences

Venous malformation (VM) is the most common form of congenital vascular malformation (CVM). VM presents at birth as an inborn vascular defect and never disappears/regresses spontaneously through the rest of life; it will continue to grow slowly at a rate that is proportional to the growth rate of the body. Haemangioma is not a vascular malformation but one of the vascular tumours originating from the endothelial cells; it develops after birth mostly in the infantile/neonatal period with a distinctive growth cycle: a proliferation phase of early rapid growth followed by an involutional phase of slow regression. Although the vascular malformation and vascular tumour belong to the ‘vascular anomaly’ together, both conditions are fundamentally different not only in their anatomical, histological and pathophysiological findings but also in their clinical courses. Therefore, an appropriate differential diagnosis of the VM is mandated not only from other kinds of CVMs but also from ‘genuine’ haemangioma. Appropriate diagnosis and assessment of VMs can be made based on clinical presentation and a proper combination of basic non-invasive studies in general but the presence of a mixed lesion involving other types of CVM lesions and the type of VM lesion, extratruncular and truncular, will dictate the need for further work-up with additional non- to less-invasive study or angiography. Otherwise, angiography is usually reserved for therapeutic planning and treatment.

Treatment for extracranial arteriovenous malformations of the head and neck

CONCLUSIONS

For extracranial arteriovenous malformations of the head and neck (HNAVMs), in which the nidus was accessible via the percutaneous route, ethanol sclerotherapy was a feasible and safe first-line treatment, although successful outcomes were obtained for only about half of the subjects. For other HNAVMs, surgical excision with embolization may be the best choice of treatment.

OBJECTIVE

To suggest a treatment protocol for patients with HNAVMs by comparing the treatment outcomes and complications of ethanol sclerotherapy with those of surgical excision combined with embolization.

MATERIAL AND METHODS

Twenty patients who had been diagnosed with HNAVM and treated between 1995 and 2002 were retrospectively reviewed. Ethanol sclerotherapy, surgical excision and embolization were used as treatments, either alone or in various combinations. The treatment outcomes and complications with the different modalities were analyzed.

RESULTS

Ethanol sclerotherapy was used for 12 cases, with a success rate of 50.0% and a permanent complication rate of 8.3%. Surgical excision combined with embolization was used for 13 patients. Although all patients achieved successful resolution of their HNAVM after surgical excision, 15.4% suffered from permanent complications. In total, 16/20 patients (80.0%) eventually achieved a > or = 75% reduction in the size of their lesions.

[Diffusion, perfusion and activation functional MRI studies of brain arteriovenous malformations]

The management of Brain Arteriovenous Malformations continues to be challenged by a lack of understanding and control of pathophysiological processes implied in the clinical symptoms. New data from functional MRI with diffusion-weighted, perfusion-weighted and neuronal activation highlight abnormal brain areas near or remote to the AVM nidus. Moreover, these techniques are able to show hemodynamic and neuronal adaptative phenomena involved in brain plasticity. They reflect the instantaneous hemodynamic brain conditions that may help to correlate the clinical symptoms with the anatomical and functional substratum and to influence any invasive therapy.

MR perfusion imaging in proliferative angiopathy

Seizures, which may be the main expression of cerebral arteriovenous malformations (CAVM) can be difficult to control medically. Our goal was to use perfusion-weighted imaging (PWI) in correlation with clinical data to detect abnormal areas of the cerebrum related to a particular type of CAVM (proliferative angiopathy) and to study the pathophysiology. We use PWI, with a bolus injection of contrast medium, to investigate seven patients with proliferative angiopathy and fits producing language disturbance. Perfusion parameters were calculated using the first-pass moment theory. Five patients had perimalformative and/or contralateral abnormal areas with relative hyperperfusion (cerebral blood volume +20.7+/-16.2%, blood flow 92.5+/-68.8 ml/min/100 g). Areas of hypoperfusion and venous congestion were detected in two patients. One patient who underwent MRI after a severe focal deficit had no significant haemodynamic abnormality.

Tc-99m RBC perfusion and blood-pool scintigraphy in the evaluation of vascular leiomyoma of the hand

A 62-year-old man with a soft, non-tender, movable mass 2.5 x 2.5-cm in diameter in the volar surface of the right index finger over the proximal phalanx underwent Tc-99m RBC perfusion and blood-pool scintigraphy to evaluate the vascular nature and extent of the mass. Highly increased activity on early and delayed blood-pool images with increased perfusion was demonstrated in the mass. The lesion with high flow rates and large blood pool spaces was considered highly suggestive of one of the various types of peripheral hemangioma. Angiography revealed a vascular neoplasm with tumor vessels. Microscopic examination of the resected tumor revealed vascular leiomyoma containing numerous dilated vascular channels. These scintigraphic abnormalities were regarded as resulting from hypervascularity demonstrated angiographically and blood pooling within the dilated vascular channels demonstrated histologically. It is concluded that Tc-99m RBC perfusion and blood pool scintigraphy may be an important non-invasive approach to demonstrate vascular leiomyoma prior to surgical biopsy or resection.

Superficial arteriovenous hemangioma of the oral cavity

OBJECTIVE

Superficial arteriovenous hemangioma (AH) is a benign vascular lesion that often affects the head and neck, but only 3 histologically proven intraoral lesions have been previously reported. The aim of this study was to analyze the clinical and histologic features of 36 oral AHs from 35 patients.

STUDY DESIGN

All vascular lesions, other than pyogenic granulomas, accessioned between 1952 and 2000 were retrieved, and clinical details were gleaned from the request forms or, when available, from the case notes. Histologic sections stained with hematoxylin-eosin were reviewed, and all selected cases were stained for smooth muscle actin and elastin.

RESULTS

The age range was 12 to 90 (mean, 53 years; median, 59). Of all patients, 54% were female. All the lesions were solitary. The labial mucosa or vermilion was affected in 17 (49%) patients, the tongue in 5, the hard palate and cheek mucosa in 4 each, the gingiva or alveolar mucosa in 3, and the floor of the mouth in 1. Clinical presentation was most often a raised lesion smaller than 20 mm. Duration ranged from months to many years. Four lesions recurred. The consistent histopathologic feature was an unencapsulated mass of blood vessels located in the lamina propria, the submucosa, or both, but 3 patterns could be discerned. The most common (in 44% of cases) comprised a diffuse mixture of thick-walled and thin-walled vessels in variable proportions. The second pattern (42%) showed a lobular arrangement of smaller vessels of uniform wall thickness, sometimes associated with an arteriole. The remaining 14% showed a tortuous pattern of angular, branching, thick-walled vessels lacking inner elastic laminae; one lesion showed both this pattern and the first pattern, one showed both the lobular morphology and the third pattern. Of the patients with the lobular arrangement, 64% were female. Smooth muscle actin was a major component of the lesional vessel walls regardless of thickness, but although most contained some fibrillary elastin, none had inner elastic laminae as prominent as those seen in adjacent true arteries. All AHs contained plump endothelial cells, and mast cell numbers were increased.

CONCLUSIONS

The etiology of AH is uncertain; endocrine and inflammatory stimuli may activate an underlying vascular malformation. Some lesions, especially those in younger patients, may be true hamartomas.