Original Research
MR Imaging of Head and Neck
Vascular Malformations’ Franqois Gelbert, MD Marie Claire Riche, MD Daniel Reizine, MD Jean-Pierre Guichard, MD Eva Assouline, MD Jonathan E. Hodes, MD Jean Jacques Merland, MD Between 1980 and 1990.150 patients with cervicofacial vascular malformations were studied at the authors’ institution with computed tomography. plain radiography. and angiography. Since 1969.34 of these patients have also undergone magnetic resonance (MR)imaging. Capillaq-venous hemangiomas seem to be the best indication for the adjunctive use of M R imaging. The venous pouches, characteristic of this type of lesion, cause elevated signal intensity, well seen on the T2-weighted images. Excellent fat and muscle differentiation with M R imaging allows appreciation of the depth ofextension of these lesions and their delimitation from normal tissue. Arteriovenous malformations (AVMs) are characterized by serpentine signal voids. indicative of the high flow rate of these lesions. Delimitation of the AVM nidus in the midst of the alferent and efferent dilated vessels is often difecult. Study of immature angiomas with M R imaging should be restricted t o lesions in specific locations (eg. orbital, laryngeal). Lymphatic malformations showed either tissular o r cystic signal intensity changes. M R imaging does not replace other studies but represents an important complementary study for the delineation and diagnosis of deep extensions of vascular malformations. allowing better planning of therapy. Index terms: Angloma 20 362 * Arterlovenous malformations 20 1495 Comparatlve studles Vascular studles JlldRI 1991: 1 579-584 Abbrerl8tlon8: AVM = arteriovenous malformaUon
’
Department of Neuroradlology and Therapeutlr Anglography Hopltal Larlbolsiere 2 Rue Ambrolse Pare 75010 Parls France Recelved AprU 14 199 1 revlslon requested May 28 revlslon recelved and accepted July 9 Address reprint requests to F G OSMRI 1991
HEAD AND NECK VASCULAR MALFORMATIONS are rare lesions and include various entities. Many classification schemes have been proposed in the literature (1-4). On the basis of cytologic findings, Mulliken and Glowacki (2.3)separated these malformations into two groups: (a)cellular malformations, termed “immature hemangiomas,” the most common vascular malformation in childhood (1.3);and (b)vascular malformations issuing from the vascular epithelium. The latter are defined by the type of vessel involved in the abnormal vascular process and by their flow velocity. Capillary, venous, capillary-venous,and lymphatic malformations are slow-flowmalformations within this group, whereas arteriovenous malformations (AVMs) are characterized by high flow velocity (1,3-5). In most cases, clinical examination and history are sufficient for classification of the malformation. Therapeutic planning (6-8) requires precise information about anatomic location and possible deep extension of the lesion. Computed tomography (CT)and, in certain cases, angiography have been used in the evaluation of cervicofacialvascular malformations. Magnetic resonance (MR) imaging has come into use more recently (9.10)and can be valuable in defining the nature and extent of these malformations and in planning medical, endovascular, or surgical therapy.
PATIENTS AND METHODS One hundred fifty patients with head and neck vascular malformations have been examined and treated in our department since 1980.Thirty-four patients with head and neck vascular malformations have been studied with MR imaging since 1989, including 23 with capillary-venousmalformations, seven with AVMs, two with immature hemangiomas, and two with lymphatic malformations. The “gold standard’ for the diagnosis was based on clinical examination and history. All studies were performed with a 0.5-T magnet (MRMAX; GE Medical Systems, Milwaukee) with spinecho T1- and T2-weighted sequences (TR msec/TE msec = 400/30 and 2,000/60, 120, respectively),with
579
two or four signals averaged. Other parameters included a 192 x 256 matrix. All patients also underwent contrast agent-enhanced CT with both bone and soft-tissue windows. Patients with AVMs underwent selective digital angiography.
RESULTS A W There were seven cases ofAVM (one cervicofacial, one nasal, four facial, and one mandibular). Clinically, the AVMs caused only slight swelling of the soft tissues and were associated with a cutaneous discoloration similar to a port-wine stain. Warmth and pulsatility indicated rapid vascular circulation in the AVMs. CT scans showed a mass effect, with contrast enhancement of muscles and soft tissue, and one case of hemifacial and hemicervical invasion. In two cases, bone windows demonstrated deformations of the face caused by the AVM. In one case, the AVM was completely intramandibular and had a lytic appearance, with contrast enhancement of the mandible. In all cases, arteriography showed multiple arteriovenous shunts corresponding to the angiomatous nidus, with early venous return in dilated veins. AU our cases had predominantly external carotid feeders. In all cases, MR images were characterized by serpentine signal voids corresponding to afferent arteries or arterialized veins with rapid flow, involving the soft tissues. Delineation of the nidus was often difficult. Differentiation of muscle and fatty tissue signal intensities on both T1- and T2-weighted images allowed good approximation of the extent of the AVM into different anatomic areas. In one patient, MR imaging enabled differentiation between the AVM and normal tissues of the base of the tongue (Fig 1).whereas clinically and with other imaging methods, the whole of the facial muscles and tongue were thought to be involved in the abnormal process. This was a crucial point for surgical treatment. MR imaging also enabled differentiation between muscle invasion and displacement, which could not be achieved with contrast-enhanced CT because of the similar attenuations of the tissues. Finally, in the complex cases (two cases of Wyburn-Mason syndrome, with a superficial midline nasal AVM and a frontobasal intracerebral AVM. respectively),MR imaging enabled concurrent definition of the superficial location of the AVM and associated intracerebral extensions.
Capillary-Venous Malformation There were 23 cases of capillary-venous malformation ( 16 temporomasseteric, one occipital, four cheek, and two cervical; 11 of these cases involved palpebral lesions). The patients presented clinically with softtissue swelling, accentuated in the decubitus position or with the Valsalva maneuver. As opposed to that of the AVMs, skin temperature was normal and the overlying skin generally has a slight bluish discoloration. CT scans showed a soft-tissue mass with slight, heterogeneous contrast agent uptake. Evidence of small calcifications (phleboliths)was visible. As with AVMs, the precise muscular extension of the lesion was difii580
JMRl
September/October 1991
cult to determine with CT scans. In these cases, we never encountered direct bone invasion, and diagnostic angiography was not indicated. In all 23 cases, MR imaging showed an isointense (TI-weighted images) homogeneous lesion. T2weighted images revealed a polylobular lesion, with homogeneous hyperintensity on the second-echo image. The T2-weighted images also demonstrated well the extensions in the superficial and deep muscles (Figs 2,3).Ten of the 16 temporomasseteric lesions had deep components; in five of these cases, the lesion extended into the parapharyngeal wall (Fig4). The palpebral lesions did not extend into the orbit. In one case, cervical malformations extended more deeply than suspected at clinical examination: in another case, there was an additional associated laryngeal location.
Immature Hemangioma There were two cases of palpebral immature hemangioma in 6-month-old babies. MR imaging was performed in both cases (before initiation of oral corticosteroid therapy) to look for associated intraorbital extension, which was not detected in either case. In both cases, the immature hemangioma was located in the internal edge of the upper eyelid. The eyelid was enlarged and had soft-tissue signal intensity on TIweighted images, with slightly increased signal intensity on T2-weighted images. No signal void was identified. Lymphatic Malformation There were two cases of lymphatic malformation, one cervical and one orbital. The cervical lesion consisted of abnormal lymphatic tissue. The orbital lesion had two components: an anterior lymphatic tissue component that had a lower signal intensity than the posterior cystic component located behind the globe, which had significantly increased, homogeneous signal intensity on T2-weighted images. Tissue lesions were isointense on T1-weighted images and had slightly increased, heterogeneous signal intensity on T2-weighted images. DISCUSSION Head and neck vascular malformations are congenital lesions with various clinical characteristics, evolutions, and indications and possibilities for treatment ( 1.5).The diagnosis is made on the basis of history and clinical examination; however, clinical examinations frequently underestimate deep extensions, and complementary radiographic studies are essential for development of a therapeutic strategy. The few cases reported in the literature that were studied with MR imaging concern mainly vascular malformations of the extremities (10).The results and conclusions of the authors were similar to ours: MR imaging provides excellent multiplanar images without the use of contrast material. Displacement and invasion of the deep musculofacial fat planes localize the lesion in various anatomic regions. The MR characteristics of the vascular malformation depend on its type (9). AVMs have an unpredictable, high-risk evolution. Complete eradication of the AVM is generally impossible to achieve, and treatment in most cases is aimed 0
a.
b.
d. Figure 1. A V M of the hemiface. (a) Lateral angiogram with left common carotid artery injection of contrast material shows external carotid artery ligatures, with opacification through collateral vessels of the A V M [arrow).(b)Sagittal T1 -weighted image
C.
(500/34)shows facial deformity and muscle invasion. with serpentine signal voids (arrows)and increased signal intensity. ( c ) Coronal T2-weighted image (200/ 1201 shows the facial deformities, serpentine signal voids, and invasion of the tongue (ar-
rows). (d)Axial T2-weighted image (2,000/120)demonstrates well the normal portion of the tongue base (*) and the delineated serpentine signal voids (arrows)of the malformation.
Volume 1
Number 5
JMRl
581
b.
a. Figure 2. Capillary-venous malformation. (a)Axial T1weighted image (600/34)shows a lesion with homogeneous signal intensity, deforming the temporomandibular muscles carrows). Note normal signal intensity of contralateral masseter muscles (*). (b)Coronal T2-weighted image shows elevated signal intensity and polylobular appearance of the malformation (arrows)and better demonstrates extension to the pterygomandibular fossa ( * ) than did the CT scan. ( c )hgiogram obtained after direct venous puncture of the malformation and injection of contrast material and before embolization with a sclerosing agent.
at reducing the size of the lesion and the risk of necrosis and hemorrhage. Treatment involves careful, stepby-step endovascular embolization and surgical excision. A s are other high-flow vascular malformations ( 11.12).AVMs are characterized on MR images by serpentine signal void. The demarcation between angiomatous and normal tissue is clearly seen (superior to that seen with CT),providing important information when a surgical approach is contemplated (8). In many cases, capillary-venous malformations ( 1,9,13.14)can be successfully treated with direct puncture and injection of a sclerosing agent in the venous pouches, followed if necessary by surgery. They have a characteristic MR appearance, especially on T2-weighted images, having a polylobular form. MR imaging can guide the direct puncture of the pouches. The coronal plane seems especially appropriate for defining the deep extensions into the pterygomaxillary and parapharyngeal areas. have a unique evoluImmature hemangiomas ( 1,6) tion. Present at birth, they evolve for 2-3 years, dur582
JMRl
September/October 1991
C.
ing which the lesion can grow considerably, with important deformation of superficial facial tissues. Spontaneous regression occurs at about the age of 6
Figures 3.4. (3)Temporomasseteric capillary-venous malformation. Coronal T2-weighted image (2.000/60,120)shows a polylobular mass with increased signal intensity invading the masseteric (single arrow),temporal (*I, and pterygoid (double arrows) muscles. (4)Temporomasseteric capillary-venous malformation with deep extension. (a)Axial CT scan demonstrates area of attenuation in soft tissue (* 1, deforming the base of the tongue, with encroachment on the pharyngeal airway (double arrows). There is poor differentiation between abnormal and normal tissues (**I. Phleboliths are visible (single arrow). (b)Coronal T2-weighted image (2,000/60,120)shows heterogeneous tissue signal intensity, with hyperintense areas (single arrow) and better delineation of muscle invasion (superficial temporal muscle, * ) than seen in a. Lesion extension into the base of the tongue and parapharyngeal (upper double arrows) and laryngeal (lower double arrows) spaces is readily seen. Motion artifacts are due to respiratory difficulties related to compression of the airway. 3.
4a.
years, with no sequelae in many cases. In rare cases, plastic surgery can be performed at that time If necessary. However, in some rare orbital or laryngeal lesions. the risk of compression of vital or functional structures during evolution may lead to treatment (in situ corticosteroids) before spontaneous regression occurs. Because of its excellent tissue resolution and
4b.
lack of x-ray radiation, MR imaging is ideal for exploring even the smallest lesion. are also wellvisuLymphatic malformations (1,161 alized with MR imaging, which demonstrates the cystic or tissue characteristics and, again, the deep extension of the lesion. Finally, the correlation of MR imaging aspects and clinical presentation generally Volume1
Number5
JMRl
583
allows good differentiation of these lesions from other soft-tissue tumors of the head and neck ( 15). In summary, head and neck vascular malformations are rare benign lesions. Functional and, in rare cases, vital prognoses depend on the type of malformation. Medical advice is generally sought because aesthetic problems result in nonnegligible psychologic problems. Therapeutic strategy is based on a multidisciplinary approach that includes dermatologists; vascular, plastic. and ear, nose, and throat surgeons; and interventional radiologists. Clinical examination generally permits recognition of the type of hemangioma. In all cases, MR imaging can be considered the best imaging modality for tissue characterization and recognition of lesion extension. Capillary-venous and lymphatic malformations and immature hemangiomas are the best indications for MR imaging. AVMs necessitate angiographic study: however, today angiography is part of endovascular treatment rather than of the diagnostic workup. For bone deformations, CT and plain radiography can be useful. 0 References Enjolras 0. Riche MC. Hemangiomes et malformations vasculaires superficielles. New York: McGraw-Hill. 1990. Fin HD, Glowacki J, Mulliken JB. Congenital vascular lesions: clinical applications of a new classification. J Pediatr Surg 1983; 18:89P900. Dethlefsen SM. Mulliken JB, Glowacki J . An ultrastructural study of mast cell interactions in hemangiomas. Ultrastruct Pathol 1986: 10:175-183.
584
JMRl
September/October 1991
4. Mulliken JB. Zetter BR. Fokman J. In vitro characteristics of endothelium from hemangiomas and vascular malformations. Surgery 1982; 92:348-353. 5. Burrows PE, Mulliken JB, Fellows KE. Strand RD. Childhood hemangiomas and vascular malformations: angiographic differentiation. AJR 1983; 141:483-488. 6. Enjolras 0. Riche MC. Merland JJ. Escande JP. The management of alarming immature hernangiomas. Pediatrics 1990; 85:491-498. 7. Riche MC. Hadjean E. Tran-Ba-Huy P. Merland JJ. The treatment of capillary-venous malformations using a new fibroslngagent. Plast Reconstr Surg 1983; 71:607-612. 8. Azzolini A, Bertani A, Riberti C. Superselective embolization and immediate surgical treatment: our present approach to treatment of large vascular hemangiomas of the face. Ann Plast Surg 1982; 9:42-60. 9. Mancuso AA, Hanafee WN. Computed tomography and magnetic resonance imaging of the head and neck. Baltimore: Williams & Wilklns, 1985. 10. Kaplan PA, Williams SM. Mucocutaneous and peripheral soft-tissue hemangiomas: MR imaging. Radiology 1987: 163: 163-166. 11. Kucharczyk W, Lemme-PleghosL, Uske A. lntracranialvascular malformations: MR and CT imaging. Radiology 1985; 165:383-389. 12. Bradley WG, Watrich V, Lai K, Fernandez E, Spalter C. The appearance of rapidly flowlng blood on magnetic resonance images. AJR 1984; 143: 1167-1 174. 13. ltoh K. Nishimura K, Togashi K, et al. MR imaging of cavernous hemangiomas of face and neck. J Comput Assist Tomogr 1986: 10:5832-5835. 14. Wolf GT, Daniel F, Krause C J . Intramuscular hernangiomas of the head and neck. Laryngoscope 1985; 95:2 10213. 15. Totty WG, Murphy WA, Lee JKT. Soft-Ussuetumors: MR imaging. Radiology 1986; 160:135-141.
MR Imaging of Head and Neck
Vascular Malformations’ Franqois Gelbert, MD Marie Claire Riche, MD Daniel Reizine, MD Jean-Pierre Guichard, MD Eva Assouline, MD Jonathan E. Hodes, MD Jean Jacques Merland, MD Between 1980 and 1990.150 patients with cervicofacial vascular malformations were studied at the authors’ institution with computed tomography. plain radiography. and angiography. Since 1969.34 of these patients have also undergone magnetic resonance (MR)imaging. Capillaq-venous hemangiomas seem to be the best indication for the adjunctive use of M R imaging. The venous pouches, characteristic of this type of lesion, cause elevated signal intensity, well seen on the T2-weighted images. Excellent fat and muscle differentiation with M R imaging allows appreciation of the depth ofextension of these lesions and their delimitation from normal tissue. Arteriovenous malformations (AVMs) are characterized by serpentine signal voids. indicative of the high flow rate of these lesions. Delimitation of the AVM nidus in the midst of the alferent and efferent dilated vessels is often difecult. Study of immature angiomas with M R imaging should be restricted t o lesions in specific locations (eg. orbital, laryngeal). Lymphatic malformations showed either tissular o r cystic signal intensity changes. M R imaging does not replace other studies but represents an important complementary study for the delineation and diagnosis of deep extensions of vascular malformations. allowing better planning of therapy. Index terms: Angloma 20 362 * Arterlovenous malformations 20 1495 Comparatlve studles Vascular studles JlldRI 1991: 1 579-584 Abbrerl8tlon8: AVM = arteriovenous malformaUon
’
Department of Neuroradlology and Therapeutlr Anglography Hopltal Larlbolsiere 2 Rue Ambrolse Pare 75010 Parls France Recelved AprU 14 199 1 revlslon requested May 28 revlslon recelved and accepted July 9 Address reprint requests to F G OSMRI 1991
HEAD AND NECK VASCULAR MALFORMATIONS are rare lesions and include various entities. Many classification schemes have been proposed in the literature (1-4). On the basis of cytologic findings, Mulliken and Glowacki (2.3)separated these malformations into two groups: (a)cellular malformations, termed “immature hemangiomas,” the most common vascular malformation in childhood (1.3);and (b)vascular malformations issuing from the vascular epithelium. The latter are defined by the type of vessel involved in the abnormal vascular process and by their flow velocity. Capillary, venous, capillary-venous,and lymphatic malformations are slow-flowmalformations within this group, whereas arteriovenous malformations (AVMs) are characterized by high flow velocity (1,3-5). In most cases, clinical examination and history are sufficient for classification of the malformation. Therapeutic planning (6-8) requires precise information about anatomic location and possible deep extension of the lesion. Computed tomography (CT)and, in certain cases, angiography have been used in the evaluation of cervicofacialvascular malformations. Magnetic resonance (MR) imaging has come into use more recently (9.10)and can be valuable in defining the nature and extent of these malformations and in planning medical, endovascular, or surgical therapy.
PATIENTS AND METHODS One hundred fifty patients with head and neck vascular malformations have been examined and treated in our department since 1980.Thirty-four patients with head and neck vascular malformations have been studied with MR imaging since 1989, including 23 with capillary-venousmalformations, seven with AVMs, two with immature hemangiomas, and two with lymphatic malformations. The “gold standard’ for the diagnosis was based on clinical examination and history. All studies were performed with a 0.5-T magnet (MRMAX; GE Medical Systems, Milwaukee) with spinecho T1- and T2-weighted sequences (TR msec/TE msec = 400/30 and 2,000/60, 120, respectively),with
579
two or four signals averaged. Other parameters included a 192 x 256 matrix. All patients also underwent contrast agent-enhanced CT with both bone and soft-tissue windows. Patients with AVMs underwent selective digital angiography.
RESULTS A W There were seven cases ofAVM (one cervicofacial, one nasal, four facial, and one mandibular). Clinically, the AVMs caused only slight swelling of the soft tissues and were associated with a cutaneous discoloration similar to a port-wine stain. Warmth and pulsatility indicated rapid vascular circulation in the AVMs. CT scans showed a mass effect, with contrast enhancement of muscles and soft tissue, and one case of hemifacial and hemicervical invasion. In two cases, bone windows demonstrated deformations of the face caused by the AVM. In one case, the AVM was completely intramandibular and had a lytic appearance, with contrast enhancement of the mandible. In all cases, arteriography showed multiple arteriovenous shunts corresponding to the angiomatous nidus, with early venous return in dilated veins. AU our cases had predominantly external carotid feeders. In all cases, MR images were characterized by serpentine signal voids corresponding to afferent arteries or arterialized veins with rapid flow, involving the soft tissues. Delineation of the nidus was often difficult. Differentiation of muscle and fatty tissue signal intensities on both T1- and T2-weighted images allowed good approximation of the extent of the AVM into different anatomic areas. In one patient, MR imaging enabled differentiation between the AVM and normal tissues of the base of the tongue (Fig 1).whereas clinically and with other imaging methods, the whole of the facial muscles and tongue were thought to be involved in the abnormal process. This was a crucial point for surgical treatment. MR imaging also enabled differentiation between muscle invasion and displacement, which could not be achieved with contrast-enhanced CT because of the similar attenuations of the tissues. Finally, in the complex cases (two cases of Wyburn-Mason syndrome, with a superficial midline nasal AVM and a frontobasal intracerebral AVM. respectively),MR imaging enabled concurrent definition of the superficial location of the AVM and associated intracerebral extensions.
Capillary-Venous Malformation There were 23 cases of capillary-venous malformation ( 16 temporomasseteric, one occipital, four cheek, and two cervical; 11 of these cases involved palpebral lesions). The patients presented clinically with softtissue swelling, accentuated in the decubitus position or with the Valsalva maneuver. As opposed to that of the AVMs, skin temperature was normal and the overlying skin generally has a slight bluish discoloration. CT scans showed a soft-tissue mass with slight, heterogeneous contrast agent uptake. Evidence of small calcifications (phleboliths)was visible. As with AVMs, the precise muscular extension of the lesion was difii580
JMRl
September/October 1991
cult to determine with CT scans. In these cases, we never encountered direct bone invasion, and diagnostic angiography was not indicated. In all 23 cases, MR imaging showed an isointense (TI-weighted images) homogeneous lesion. T2weighted images revealed a polylobular lesion, with homogeneous hyperintensity on the second-echo image. The T2-weighted images also demonstrated well the extensions in the superficial and deep muscles (Figs 2,3).Ten of the 16 temporomasseteric lesions had deep components; in five of these cases, the lesion extended into the parapharyngeal wall (Fig4). The palpebral lesions did not extend into the orbit. In one case, cervical malformations extended more deeply than suspected at clinical examination: in another case, there was an additional associated laryngeal location.
Immature Hemangioma There were two cases of palpebral immature hemangioma in 6-month-old babies. MR imaging was performed in both cases (before initiation of oral corticosteroid therapy) to look for associated intraorbital extension, which was not detected in either case. In both cases, the immature hemangioma was located in the internal edge of the upper eyelid. The eyelid was enlarged and had soft-tissue signal intensity on TIweighted images, with slightly increased signal intensity on T2-weighted images. No signal void was identified. Lymphatic Malformation There were two cases of lymphatic malformation, one cervical and one orbital. The cervical lesion consisted of abnormal lymphatic tissue. The orbital lesion had two components: an anterior lymphatic tissue component that had a lower signal intensity than the posterior cystic component located behind the globe, which had significantly increased, homogeneous signal intensity on T2-weighted images. Tissue lesions were isointense on T1-weighted images and had slightly increased, heterogeneous signal intensity on T2-weighted images. DISCUSSION Head and neck vascular malformations are congenital lesions with various clinical characteristics, evolutions, and indications and possibilities for treatment ( 1.5).The diagnosis is made on the basis of history and clinical examination; however, clinical examinations frequently underestimate deep extensions, and complementary radiographic studies are essential for development of a therapeutic strategy. The few cases reported in the literature that were studied with MR imaging concern mainly vascular malformations of the extremities (10).The results and conclusions of the authors were similar to ours: MR imaging provides excellent multiplanar images without the use of contrast material. Displacement and invasion of the deep musculofacial fat planes localize the lesion in various anatomic regions. The MR characteristics of the vascular malformation depend on its type (9). AVMs have an unpredictable, high-risk evolution. Complete eradication of the AVM is generally impossible to achieve, and treatment in most cases is aimed 0
a.
b.
d. Figure 1. A V M of the hemiface. (a) Lateral angiogram with left common carotid artery injection of contrast material shows external carotid artery ligatures, with opacification through collateral vessels of the A V M [arrow).(b)Sagittal T1 -weighted image
C.
(500/34)shows facial deformity and muscle invasion. with serpentine signal voids (arrows)and increased signal intensity. ( c ) Coronal T2-weighted image (200/ 1201 shows the facial deformities, serpentine signal voids, and invasion of the tongue (ar-
rows). (d)Axial T2-weighted image (2,000/120)demonstrates well the normal portion of the tongue base (*) and the delineated serpentine signal voids (arrows)of the malformation.
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Number 5
JMRl
581
b.
a. Figure 2. Capillary-venous malformation. (a)Axial T1weighted image (600/34)shows a lesion with homogeneous signal intensity, deforming the temporomandibular muscles carrows). Note normal signal intensity of contralateral masseter muscles (*). (b)Coronal T2-weighted image shows elevated signal intensity and polylobular appearance of the malformation (arrows)and better demonstrates extension to the pterygomandibular fossa ( * ) than did the CT scan. ( c )hgiogram obtained after direct venous puncture of the malformation and injection of contrast material and before embolization with a sclerosing agent.
at reducing the size of the lesion and the risk of necrosis and hemorrhage. Treatment involves careful, stepby-step endovascular embolization and surgical excision. A s are other high-flow vascular malformations ( 11.12).AVMs are characterized on MR images by serpentine signal void. The demarcation between angiomatous and normal tissue is clearly seen (superior to that seen with CT),providing important information when a surgical approach is contemplated (8). In many cases, capillary-venous malformations ( 1,9,13.14)can be successfully treated with direct puncture and injection of a sclerosing agent in the venous pouches, followed if necessary by surgery. They have a characteristic MR appearance, especially on T2-weighted images, having a polylobular form. MR imaging can guide the direct puncture of the pouches. The coronal plane seems especially appropriate for defining the deep extensions into the pterygomaxillary and parapharyngeal areas. have a unique evoluImmature hemangiomas ( 1,6) tion. Present at birth, they evolve for 2-3 years, dur582
JMRl
September/October 1991
C.
ing which the lesion can grow considerably, with important deformation of superficial facial tissues. Spontaneous regression occurs at about the age of 6
Figures 3.4. (3)Temporomasseteric capillary-venous malformation. Coronal T2-weighted image (2.000/60,120)shows a polylobular mass with increased signal intensity invading the masseteric (single arrow),temporal (*I, and pterygoid (double arrows) muscles. (4)Temporomasseteric capillary-venous malformation with deep extension. (a)Axial CT scan demonstrates area of attenuation in soft tissue (* 1, deforming the base of the tongue, with encroachment on the pharyngeal airway (double arrows). There is poor differentiation between abnormal and normal tissues (**I. Phleboliths are visible (single arrow). (b)Coronal T2-weighted image (2,000/60,120)shows heterogeneous tissue signal intensity, with hyperintense areas (single arrow) and better delineation of muscle invasion (superficial temporal muscle, * ) than seen in a. Lesion extension into the base of the tongue and parapharyngeal (upper double arrows) and laryngeal (lower double arrows) spaces is readily seen. Motion artifacts are due to respiratory difficulties related to compression of the airway. 3.
4a.
years, with no sequelae in many cases. In rare cases, plastic surgery can be performed at that time If necessary. However, in some rare orbital or laryngeal lesions. the risk of compression of vital or functional structures during evolution may lead to treatment (in situ corticosteroids) before spontaneous regression occurs. Because of its excellent tissue resolution and
4b.
lack of x-ray radiation, MR imaging is ideal for exploring even the smallest lesion. are also wellvisuLymphatic malformations (1,161 alized with MR imaging, which demonstrates the cystic or tissue characteristics and, again, the deep extension of the lesion. Finally, the correlation of MR imaging aspects and clinical presentation generally Volume1
Number5
JMRl
583
allows good differentiation of these lesions from other soft-tissue tumors of the head and neck ( 15). In summary, head and neck vascular malformations are rare benign lesions. Functional and, in rare cases, vital prognoses depend on the type of malformation. Medical advice is generally sought because aesthetic problems result in nonnegligible psychologic problems. Therapeutic strategy is based on a multidisciplinary approach that includes dermatologists; vascular, plastic. and ear, nose, and throat surgeons; and interventional radiologists. Clinical examination generally permits recognition of the type of hemangioma. In all cases, MR imaging can be considered the best imaging modality for tissue characterization and recognition of lesion extension. Capillary-venous and lymphatic malformations and immature hemangiomas are the best indications for MR imaging. AVMs necessitate angiographic study: however, today angiography is part of endovascular treatment rather than of the diagnostic workup. For bone deformations, CT and plain radiography can be useful. 0 References Enjolras 0. Riche MC. Hemangiomes et malformations vasculaires superficielles. New York: McGraw-Hill. 1990. Fin HD, Glowacki J, Mulliken JB. Congenital vascular lesions: clinical applications of a new classification. J Pediatr Surg 1983; 18:89P900. Dethlefsen SM. Mulliken JB, Glowacki J . An ultrastructural study of mast cell interactions in hemangiomas. Ultrastruct Pathol 1986: 10:175-183.
584
JMRl
September/October 1991
4. Mulliken JB. Zetter BR. Fokman J. In vitro characteristics of endothelium from hemangiomas and vascular malformations. Surgery 1982; 92:348-353. 5. Burrows PE, Mulliken JB, Fellows KE. Strand RD. Childhood hemangiomas and vascular malformations: angiographic differentiation. AJR 1983; 141:483-488. 6. Enjolras 0. Riche MC. Merland JJ. Escande JP. The management of alarming immature hernangiomas. Pediatrics 1990; 85:491-498. 7. Riche MC. Hadjean E. Tran-Ba-Huy P. Merland JJ. The treatment of capillary-venous malformations using a new fibroslngagent. Plast Reconstr Surg 1983; 71:607-612. 8. Azzolini A, Bertani A, Riberti C. Superselective embolization and immediate surgical treatment: our present approach to treatment of large vascular hemangiomas of the face. Ann Plast Surg 1982; 9:42-60. 9. Mancuso AA, Hanafee WN. Computed tomography and magnetic resonance imaging of the head and neck. Baltimore: Williams & Wilklns, 1985. 10. Kaplan PA, Williams SM. Mucocutaneous and peripheral soft-tissue hemangiomas: MR imaging. Radiology 1987: 163: 163-166. 11. Kucharczyk W, Lemme-PleghosL, Uske A. lntracranialvascular malformations: MR and CT imaging. Radiology 1985; 165:383-389. 12. Bradley WG, Watrich V, Lai K, Fernandez E, Spalter C. The appearance of rapidly flowlng blood on magnetic resonance images. AJR 1984; 143: 1167-1 174. 13. ltoh K. Nishimura K, Togashi K, et al. MR imaging of cavernous hemangiomas of face and neck. J Comput Assist Tomogr 1986: 10:5832-5835. 14. Wolf GT, Daniel F, Krause C J . Intramuscular hernangiomas of the head and neck. Laryngoscope 1985; 95:2 10213. 15. Totty WG, Murphy WA, Lee JKT. Soft-Ussuetumors: MR imaging. Radiology 1986; 160:135-141.
