INTERESTING IMAGE
Utility of 99mTc RBC Scintigraphy in Diagnosing Parotid Venous Malformations Rosan Patel, MD,* Hannan Saad, BS,† Ashok Srinivasan, MD,* and Richard K.J. Brown, MD* Abstract: Venous malformations of the parotid glands are uncommon and can be difficult to confirm on routine anatomical imaging alone because of overlap of imaging features with other more common parotid lesions. 99mTc RBC scans combined with SPECT/CT offer a noninvasive way to diagnose parotid venous malformations without the need for biopsy. Combined with anatomical findings of phleboliths (when present), the diagnosis can be reliably determined. We present a case where MRI and biopsy were inconclusive, but the SPECT/CT was used to confirm the suspicion of a benign venous malformation. Key Words: venous malformations, sodium pertechnetate–labeled RBC, tagged RBC, hemangioma, parotid (Clin Nucl Med 2015;40: e372–e374) Received for publication November 12, 2014; revision accepted March 11, 2015. From the *Department of Radiology, University of Michigan, Ann Arbor; and †Wayne State School of Medicine, Detroit, MI. Conflicts of interest and sources of funding: none declared. Reprints: Richard K.J. Brown, MD, Department of Radiology, University of Michigan Health System, 1500 E. Medical Center Drive, UH B1G505, Ann Arbor, MI 48109–5030. E-mail: [email protected]. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0363-9762/15/4007–0372
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REFERENCES 1. Buckmiller LM, Richter GT, Suen JY. Diagnosis and management of hemangiomas and vascular malformations of the head and neck. Oral Dis. 2010;16:405–418. 2. Espinoza S, Halimi P. Interpretation pearls for MR imaging of parotid gland tumor. Eur Ann Otorhinolaryngol Head Neck Dis. 2013;130:30–35. 3. Kern S, Niemeyer C, Darge K, et al. Differentiation of vascular birthmarks by MR imaging. An investigation of hemangiomas, venous and lymphatic malformations. Acta Radiol. 2000;41:453–457. 4. Mandel L, Perrino MA: Phleboliths and the vascular maxillofacial lesion. J Oral Maxillofac Surg. 2010;68:1973–1976. 5. Fiore F, Califano L, Cortese A, et al. Hemangiomas of the maxillofacial area. Usefulness of 99Tcm-labelled red cell scintigraphy. Nucl Med Commun. 1993; 14:378–383. 6. Schillaci O, Danieli R, Manni C, et al. Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera. Eur J Nucl Med Mol Imaging. 2004;31:1011–1015. 7. Burroni L, Borsari G, Pichierri P, et al. Preoperative diagnosis of orbital cavernous hemangioma: a 99mTc-RBC SPECT study. Clin Nucl Med. 2012;37:1041–1046. 8. Zaghi S, Hendizadeh L, Hung T, et al. MRI criteria for the diagnosis of pleomorphic adenoma: a validation study. Am J Otolaryngol. 2014;35:713–718.
Clinical Nuclear Medicine • Volume 40, Number 7, July 2015 Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
Clinical Nuclear Medicine • Volume 40, Number 7, July 2015
99m
Tc RBC Scintigraphy and Venous Malformations
FIGURE 1. A 59-year-old woman presented with left parotid gland swelling 4 years earlier for which surgery was performed but revealed only benign salivary gland tissue and a reactive lymph node. She presented with ongoing parotid swelling afterward for which an MRI was performed that demonstrated a lobulated, heterogeneously enhancing mass within the left parotid gland that was T2 hyperintense (arrow). Although the differential diagnosis included pleomorphic adenoma (most likely), Warthin tumor, and other carcinomas (less likely), the absence of any specific pathology on the earlier surgery prompted the possibility of uncommon lesions such as venous or venolymphatic malformation.1–4 Because MRI was inconclusive and serial MRIs showed varying size of the lesion, 99mTc labeled red blood cell scintigraphy was performed to further characterize the lesion.
© 2015 Wolters Kluwer Health, Inc. All rights reserved. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
www.nuclearmed.com
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Patel et al
Clinical Nuclear Medicine • Volume 40, Number 7, July 2015
FIGURE 2. 99mTc sodium pertechnetate labeled red blood cells were injected followed by blood pool and flow imaging of the anterior and lateral head and a SPECT-CT at 2.5 hours after injection. Findings show increased radiotracer activity in the left parotid gland. SPECT-CT imaging shows a calcification within this region not previously seen in previous imaging. These phleboliths are commonly found in venous malformations.5 Previous studies have characterized the scintigraphic pattern of venous malformations (often termed as cavernous hemangiomas) as hypoactivity in the arterial phase with increased activity in the blood pool and most radiotracer activity in the delayed phase (2 hours post). In contrast, arteriovenous malformations tend to display most activity in the arterial phase with decreased subsequent activity.6–8 Our findings in this case demonstrate how a lesion in the parotid gland, which has previously demonstrated equivocal results by MRI and biopsy, can be evaluated with 99mTc sodium pertechnetate-labeled red blood cells when there is an index of suspicion for a vascular lesion.
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www.nuclearmed.com
© 2015 Wolters Kluwer Health, Inc. All rights reserved. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
Utility of 99mTc RBC Scintigraphy in Diagnosing Parotid Venous Malformations Rosan Patel, MD,* Hannan Saad, BS,† Ashok Srinivasan, MD,* and Richard K.J. Brown, MD* Abstract: Venous malformations of the parotid glands are uncommon and can be difficult to confirm on routine anatomical imaging alone because of overlap of imaging features with other more common parotid lesions. 99mTc RBC scans combined with SPECT/CT offer a noninvasive way to diagnose parotid venous malformations without the need for biopsy. Combined with anatomical findings of phleboliths (when present), the diagnosis can be reliably determined. We present a case where MRI and biopsy were inconclusive, but the SPECT/CT was used to confirm the suspicion of a benign venous malformation. Key Words: venous malformations, sodium pertechnetate–labeled RBC, tagged RBC, hemangioma, parotid (Clin Nucl Med 2015;40: e372–e374) Received for publication November 12, 2014; revision accepted March 11, 2015. From the *Department of Radiology, University of Michigan, Ann Arbor; and †Wayne State School of Medicine, Detroit, MI. Conflicts of interest and sources of funding: none declared. Reprints: Richard K.J. Brown, MD, Department of Radiology, University of Michigan Health System, 1500 E. Medical Center Drive, UH B1G505, Ann Arbor, MI 48109–5030. E-mail: [email protected]. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0363-9762/15/4007–0372
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www.nuclearmed.com
REFERENCES 1. Buckmiller LM, Richter GT, Suen JY. Diagnosis and management of hemangiomas and vascular malformations of the head and neck. Oral Dis. 2010;16:405–418. 2. Espinoza S, Halimi P. Interpretation pearls for MR imaging of parotid gland tumor. Eur Ann Otorhinolaryngol Head Neck Dis. 2013;130:30–35. 3. Kern S, Niemeyer C, Darge K, et al. Differentiation of vascular birthmarks by MR imaging. An investigation of hemangiomas, venous and lymphatic malformations. Acta Radiol. 2000;41:453–457. 4. Mandel L, Perrino MA: Phleboliths and the vascular maxillofacial lesion. J Oral Maxillofac Surg. 2010;68:1973–1976. 5. Fiore F, Califano L, Cortese A, et al. Hemangiomas of the maxillofacial area. Usefulness of 99Tcm-labelled red cell scintigraphy. Nucl Med Commun. 1993; 14:378–383. 6. Schillaci O, Danieli R, Manni C, et al. Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera. Eur J Nucl Med Mol Imaging. 2004;31:1011–1015. 7. Burroni L, Borsari G, Pichierri P, et al. Preoperative diagnosis of orbital cavernous hemangioma: a 99mTc-RBC SPECT study. Clin Nucl Med. 2012;37:1041–1046. 8. Zaghi S, Hendizadeh L, Hung T, et al. MRI criteria for the diagnosis of pleomorphic adenoma: a validation study. Am J Otolaryngol. 2014;35:713–718.
Clinical Nuclear Medicine • Volume 40, Number 7, July 2015 Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
Clinical Nuclear Medicine • Volume 40, Number 7, July 2015
99m
Tc RBC Scintigraphy and Venous Malformations
FIGURE 1. A 59-year-old woman presented with left parotid gland swelling 4 years earlier for which surgery was performed but revealed only benign salivary gland tissue and a reactive lymph node. She presented with ongoing parotid swelling afterward for which an MRI was performed that demonstrated a lobulated, heterogeneously enhancing mass within the left parotid gland that was T2 hyperintense (arrow). Although the differential diagnosis included pleomorphic adenoma (most likely), Warthin tumor, and other carcinomas (less likely), the absence of any specific pathology on the earlier surgery prompted the possibility of uncommon lesions such as venous or venolymphatic malformation.1–4 Because MRI was inconclusive and serial MRIs showed varying size of the lesion, 99mTc labeled red blood cell scintigraphy was performed to further characterize the lesion.
© 2015 Wolters Kluwer Health, Inc. All rights reserved. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
www.nuclearmed.com
e373
Patel et al
Clinical Nuclear Medicine • Volume 40, Number 7, July 2015
FIGURE 2. 99mTc sodium pertechnetate labeled red blood cells were injected followed by blood pool and flow imaging of the anterior and lateral head and a SPECT-CT at 2.5 hours after injection. Findings show increased radiotracer activity in the left parotid gland. SPECT-CT imaging shows a calcification within this region not previously seen in previous imaging. These phleboliths are commonly found in venous malformations.5 Previous studies have characterized the scintigraphic pattern of venous malformations (often termed as cavernous hemangiomas) as hypoactivity in the arterial phase with increased activity in the blood pool and most radiotracer activity in the delayed phase (2 hours post). In contrast, arteriovenous malformations tend to display most activity in the arterial phase with decreased subsequent activity.6–8 Our findings in this case demonstrate how a lesion in the parotid gland, which has previously demonstrated equivocal results by MRI and biopsy, can be evaluated with 99mTc sodium pertechnetate-labeled red blood cells when there is an index of suspicion for a vascular lesion.
e374
www.nuclearmed.com
© 2015 Wolters Kluwer Health, Inc. All rights reserved. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
