A case of arteriovenous malformations of tongue, sublingual & submandibular spaces causing severe macroglossia

A 54 years old female patient presented with severe macroglossia and difficulty in speaking and swallowing since 3 months. The patient had a large tongue since childhood but was asymptomatic. She complains of increase in size of tongue since last year.

No history of oral hemorrhages. Not a known case of any malignancies.

Frontal and lateral radiographs of the face show grossly enlarged tongue with multiple radiodense foci.

Ultrasound evaluation of the tongue showed an ill-defined hyperechoic lesion involving the tongue with multiple anechoic spaces which showed colour uptake and both arterial and venous waveforms were noted. Few of the spaces showed no color uptake and phleboliths were noted within

Contrast-enhanced CT scan showed multiple ill-defined lesions were noted in the tongue, submandibular space and sublingual space. Contrast-filled vascular spaces were noted within, with bilateral lingual arteries as the feeding arteries and bilateral internal jugular vein as the draining veins. Remodeling of mandible and splaying of teeth was noted. There was non-visualization of lower central and left lateral incisors. Few of the venous channels were completely thrombosed.

Background

Vascular malformations are common lesions in the head and neck region. When localized in the tongue, they can cause clinical problems such as spontaneous hemorrhage from the mouth[1]. Arteriovenous malformation of the tongue is a rare craniofacial vascular anomaly. Although uncommon, progressive asymmetric growth of the tongue (macroglossia) can be observed [2]. AVMs are composed of a central nidus with anomalous arteriovenous shunts and a network of surrounding collateral vessels [3]. The shunting between the high-pressure arterial and low-pressure venous system accounts for the clinical presentation, anatomical changes, and progression of the lesions [4]

Clinical Perspective

AVMs are often present at birth but manifest in childhood or adolescence. As AVM has a slow onset and progression, it is seldom associated with cardiomegaly and high-output cardiac failure [5]. AVMs occur equally in both sexes, the size of lesion may increase as a result of infection, trauma, ligation, or due to hormonal influences as during pregnancy and puberty. Imaging is needed to depict the extent and lack of invasion of these lesions and for differentiating between high- and low-flow lesions [6]

Imaging Perspective

Plain radiography and CT scans have limited role as diagnostic tools in high-flow vascular malformations; the diagnosis is usually made with Doppler ultrasonography. MRI helps differentiate between high- and low-flow lesions [6]. Angiography is useful in poorly defined cases and for embolization before surgery. It demonstrates the flow characteristics, feeding vessels, and dangerous anastomoses. Characteristic angiography findings are marked hypertrophy and tortuosity in the feeding vessels.

Outcome

Treatment is usually indicated for an asymptomatic AVM. After diagnosis, patients should be followed up at 6-month intervals. Intervention should not be done until there are signs and symptoms or concern for endangering vital structures [3]. Ligation or proximal embolization of feeding vessels should not be done. This will cause rapid recruitment of flow from adjacent arteries and denies access to embolization. Selective arterial or retrograde venous embolization may be used for treatment of AVM which is not suitable for surgery.

Take Home Message / Teaching Points

In patients with macroglossia, although arteriovenous malformations of tongue are rare, they should be kept as a differential diagnosis, as the condition can lead to potential complications such as hemorrhage.