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Anatomical and functional imaging in endocrine hypertension.

Chaudhary V, Bano S - Indian J Endocrinol Metab (2012)

Bottom Line: In endocrine hypertension, hormonal excess results in clinically significant hypertension.The functional imaging (such as radionuclide imaging) complements anatomy-based imaging (such as ultrasound, computed tomography, and magnetic resonance imaging) to facilitate diagnostic localization of a lesion causing endocrine hypertension.The aim of this review article is to familiarize general radiologists, endocrinologists, and clinicians with various anatomical and functional imaging techniques used in patients with endocrine hypertension.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiodiagnosis, Employees' State Insurance Corporation (ESIC) Model Hospital, Gurgaon, Haryana, India.

ABSTRACT
In endocrine hypertension, hormonal excess results in clinically significant hypertension. The functional imaging (such as radionuclide imaging) complements anatomy-based imaging (such as ultrasound, computed tomography, and magnetic resonance imaging) to facilitate diagnostic localization of a lesion causing endocrine hypertension. The aim of this review article is to familiarize general radiologists, endocrinologists, and clinicians with various anatomical and functional imaging techniques used in patients with endocrine hypertension.

No MeSH data available.


Related in: MedlinePlus

Pheochromocytoma. MRI abdomen in a 40-year-old male demonstrates a large right adrenal mass (arrow) appearing hypointense on axial T1-weighted image (a) and hyperintense on axial fat- suppressed T2-weighted image. (b) Postcontrast axial T1-weighted image (c) demonstrates marked but heterogeneous enhancement of the lesion. Clinically silent pheochromocytomas tend to be larger. The diagnosis of pheochromocytoma was confirmed on histopathological examination.
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Figure 3: Pheochromocytoma. MRI abdomen in a 40-year-old male demonstrates a large right adrenal mass (arrow) appearing hypointense on axial T1-weighted image (a) and hyperintense on axial fat- suppressed T2-weighted image. (b) Postcontrast axial T1-weighted image (c) demonstrates marked but heterogeneous enhancement of the lesion. Clinically silent pheochromocytomas tend to be larger. The diagnosis of pheochromocytoma was confirmed on histopathological examination.

Mentions: Phaeochromocytoma (PH) is an important but rare cause of endocrine hypertension, occurring in about 0.1–0.9% of hypertensive individuals. PHs are rare neuroendocrine tumors of chromaffin tissue, most commonly found in adrenal medulla. These tumors produce excessive amounts of catecholamines (noradrenaline, adrenaline), responsible for paroxysmal hypertension. Approximately, 90% of PHs occurs within the adrenal glands, while 10% are located outside the adrenal glands (extra-adrenal) at various locations in the body. Extra-adrenal PHs are also known as paragangliomas. About 10% of the tumors are malignant, and substantial proportions (up to 25%) of apparent sporadic pheochromocytomas occur as part of familial syndromes, including MEN2 and VHL.[30] A combination of anatomical and functional imaging studies yield a sensitivity of nearly 100% for diagnosing these catecholamine-producing neoplasms. CT and MRI are generally indicated as primary imaging modalities for localization of these tumors. Sensitivities vary between 75% and 100% depending on location at adrenal or extra-adrenal sites and whether the tumor is primary, recurrent, or metastatic. Both imaging methods have poor specificity. However, MRI is more sensitive than CT in detecting extra-adrenal pheochromocytomas (paragangliomas), and is considered as the anatomic imaging of choice because of its excellent anatomic detail, potential for better tissue characterization and multiplanar image capability.[31] PHs are usually 2–5 cm in diameter, solid, hypervascular masses, frequently with central necrosis, hemorrhage, and calcification. On MRI, most PHs are hypointense on T1-weighted images and markedly hyperintense on T2-weighted and fat suppressed T2-weighted images; however, low signal PHs (>30%) may be encountered at T2-weighted imaging. PHs commonly show avid but inhomogeneous enhancement after intravenous administration of contrast material [Figure 3]. Rarely, PHs may contain sufficient fat or may demonstrate rapid contrast washout and be mistaken for an adenoma at CT or MRI. Ten percent of PHs are found to be malignant; but unfortunately, the anatomic imaging features cannot sufficiently discriminate between benign and malignant PHs. Metastatic spread is the only reliable criterion for diagnosis of malignant PHs. Skeleton, lymph nodes, lung, and peritoneum are the most common sites for metastases. Iodine-131 or 123I metaiodobenzylguanidine (MIBG) scintigraphy has 100% specificity but limited sensitivity (87%) and spatial resolution in detecting PHs. Single-photon emission scanning with [123I] metaiodobenzylguanidine improves both sensitivity and spatial resolution.[32] Radionuclide scanning is often useful when clinically suspected PHs (i.e., extra-adrenal lesions) cannot be localized by imaging techniques and particularly for metastatic PHs. Somatostatin receptor scintigraphy with octreotide, an analogue of somatostatin, can also localize PHs, but in less than 30% cases. In present scenario, 18F-fluoro-2-deoxy-D-glucose (18F-FDG) or 18F-fluorodihydroxyphenylalanine (18F-DOPA)-PET is the most commonly used functional imaging technique in clinical practice to detect and localize PHs. PHs usually show increased uptake on 18F-FDG or 18F-fluorodihydroxyphenylalanine PET scans.[33–35] The sensitivity of 18FDG-PET scanning is about 70% and that of 18F-fluorodihydroxyphenylalanine about 100% for detecting solitary pheochromocytoma.[3334] The newly introduced 68Ga-DOTA radiopharmaceuticals for PET/CT imaging are particularly useful to detect more malignant lesions.[36]


Anatomical and functional imaging in endocrine hypertension.

Chaudhary V, Bano S - Indian J Endocrinol Metab (2012)

Pheochromocytoma. MRI abdomen in a 40-year-old male demonstrates a large right adrenal mass (arrow) appearing hypointense on axial T1-weighted image (a) and hyperintense on axial fat- suppressed T2-weighted image. (b) Postcontrast axial T1-weighted image (c) demonstrates marked but heterogeneous enhancement of the lesion. Clinically silent pheochromocytomas tend to be larger. The diagnosis of pheochromocytoma was confirmed on histopathological examination.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3475894&req=5

Figure 3: Pheochromocytoma. MRI abdomen in a 40-year-old male demonstrates a large right adrenal mass (arrow) appearing hypointense on axial T1-weighted image (a) and hyperintense on axial fat- suppressed T2-weighted image. (b) Postcontrast axial T1-weighted image (c) demonstrates marked but heterogeneous enhancement of the lesion. Clinically silent pheochromocytomas tend to be larger. The diagnosis of pheochromocytoma was confirmed on histopathological examination.
Mentions: Phaeochromocytoma (PH) is an important but rare cause of endocrine hypertension, occurring in about 0.1–0.9% of hypertensive individuals. PHs are rare neuroendocrine tumors of chromaffin tissue, most commonly found in adrenal medulla. These tumors produce excessive amounts of catecholamines (noradrenaline, adrenaline), responsible for paroxysmal hypertension. Approximately, 90% of PHs occurs within the adrenal glands, while 10% are located outside the adrenal glands (extra-adrenal) at various locations in the body. Extra-adrenal PHs are also known as paragangliomas. About 10% of the tumors are malignant, and substantial proportions (up to 25%) of apparent sporadic pheochromocytomas occur as part of familial syndromes, including MEN2 and VHL.[30] A combination of anatomical and functional imaging studies yield a sensitivity of nearly 100% for diagnosing these catecholamine-producing neoplasms. CT and MRI are generally indicated as primary imaging modalities for localization of these tumors. Sensitivities vary between 75% and 100% depending on location at adrenal or extra-adrenal sites and whether the tumor is primary, recurrent, or metastatic. Both imaging methods have poor specificity. However, MRI is more sensitive than CT in detecting extra-adrenal pheochromocytomas (paragangliomas), and is considered as the anatomic imaging of choice because of its excellent anatomic detail, potential for better tissue characterization and multiplanar image capability.[31] PHs are usually 2–5 cm in diameter, solid, hypervascular masses, frequently with central necrosis, hemorrhage, and calcification. On MRI, most PHs are hypointense on T1-weighted images and markedly hyperintense on T2-weighted and fat suppressed T2-weighted images; however, low signal PHs (>30%) may be encountered at T2-weighted imaging. PHs commonly show avid but inhomogeneous enhancement after intravenous administration of contrast material [Figure 3]. Rarely, PHs may contain sufficient fat or may demonstrate rapid contrast washout and be mistaken for an adenoma at CT or MRI. Ten percent of PHs are found to be malignant; but unfortunately, the anatomic imaging features cannot sufficiently discriminate between benign and malignant PHs. Metastatic spread is the only reliable criterion for diagnosis of malignant PHs. Skeleton, lymph nodes, lung, and peritoneum are the most common sites for metastases. Iodine-131 or 123I metaiodobenzylguanidine (MIBG) scintigraphy has 100% specificity but limited sensitivity (87%) and spatial resolution in detecting PHs. Single-photon emission scanning with [123I] metaiodobenzylguanidine improves both sensitivity and spatial resolution.[32] Radionuclide scanning is often useful when clinically suspected PHs (i.e., extra-adrenal lesions) cannot be localized by imaging techniques and particularly for metastatic PHs. Somatostatin receptor scintigraphy with octreotide, an analogue of somatostatin, can also localize PHs, but in less than 30% cases. In present scenario, 18F-fluoro-2-deoxy-D-glucose (18F-FDG) or 18F-fluorodihydroxyphenylalanine (18F-DOPA)-PET is the most commonly used functional imaging technique in clinical practice to detect and localize PHs. PHs usually show increased uptake on 18F-FDG or 18F-fluorodihydroxyphenylalanine PET scans.[33–35] The sensitivity of 18FDG-PET scanning is about 70% and that of 18F-fluorodihydroxyphenylalanine about 100% for detecting solitary pheochromocytoma.[3334] The newly introduced 68Ga-DOTA radiopharmaceuticals for PET/CT imaging are particularly useful to detect more malignant lesions.[36]

Bottom Line: In endocrine hypertension, hormonal excess results in clinically significant hypertension.The functional imaging (such as radionuclide imaging) complements anatomy-based imaging (such as ultrasound, computed tomography, and magnetic resonance imaging) to facilitate diagnostic localization of a lesion causing endocrine hypertension.The aim of this review article is to familiarize general radiologists, endocrinologists, and clinicians with various anatomical and functional imaging techniques used in patients with endocrine hypertension.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiodiagnosis, Employees' State Insurance Corporation (ESIC) Model Hospital, Gurgaon, Haryana, India.

ABSTRACT
In endocrine hypertension, hormonal excess results in clinically significant hypertension. The functional imaging (such as radionuclide imaging) complements anatomy-based imaging (such as ultrasound, computed tomography, and magnetic resonance imaging) to facilitate diagnostic localization of a lesion causing endocrine hypertension. The aim of this review article is to familiarize general radiologists, endocrinologists, and clinicians with various anatomical and functional imaging techniques used in patients with endocrine hypertension.

No MeSH data available.


Related in: MedlinePlus