الفهرس 
ADRENAL ANATOMYOnly 14 pages are availabe for public view
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Abstract
The adrenal glands are small highly vascular, friable, paired organs lying superomedial to each upper renal pole. Each gland consists of two units, cortex and medulla different genetically, structurally and functionally. Adrenal cortex is divided hisologically into 3 zones secreting glucocorticoids, mineralocorticoids and sex hormone while adrenal medulla secrets catecholamines.
Adrenal gland disorders can be classified to cortical disorders (functional adenomas, carcinomas and hyperplasia), medullary disorders (pheochromocytoma), adrenal incidentalomas and other rare masses.
Cushing’s syndrome occur due to prolonged glucocorticoids exposure either ACTH dependent or non-ACTH dependent. This syndrome can cause many clinical morbidities and complications and may present as biochemical diagnosis without classical features (subclinical Cushing’s). Diagnosis of cushing’s syndrome is accomplished by 24 hr UFC, dexamethasone suppression test, loss of diurnal rhythm and other tests.
Primary aldosteronism occurs due to aldosterone secreting adrenal tumor and can cause hypertension and unprovoked hypokalemia. Diagnosis is accomplished by measurement of serum K+ and PA/PRA level. Localization of tumor side can be achieved by scintigraphy or adrenal venous sampling.
Pheochromocytoma is a rare, but lethal cause of adrenal masses which can cause hypertension and cardiovascular crises although it may be silent. So, early diagnosis by measurement of catecholamines and their metabolites in blood or urine is crucial followed by localization and detection of extra-adrenal tumors. After diagnosis is confirmed tumor has to be excised with good pre-operative and intra-operative monitoring and preparations and cautious dissection.
Adrenal metastases (secondaries) are more common than primary adrenal carcinomas and managed according to underlying malignancy. Carcinomas are rare and carry very poor prognosis. Excision of carcinoma showed increase in survival rates in early stages.
Adrenal incidentalomas represent a common finding recognized more often nowadays due to increased use of imaging techniques, most of incidentalomas are benign and non-functioning but minimal biochemical screening and radiological evaluation should be performed to detect malignant and functional masses.
Adrenal masses are characterized according to functional status and malignant potential. Functional and malignant tumors have to be excised while benign non-functional masses can be followed up for size change and development of hormone overproduction.
Initial evaluation of adrenal masses should be achieved by history, physical examination and biochemical evaluation by screening tests followed by confirmatory tests for definite diagnosis if positive results were obtained from screening tests.
Radiological evaluation plays critical role in the detection of adrenal abnormalities and characterizing them as benign or malignant. CT, non-enhanced and contrast-enhanced is the primary most valuable imaging technique for detection and characterization of adrenal masses based on their size, shape, attenuation values and percentage of washout of contrast. MRI with its different techniques as chemical shift, fat suppression and contrast enhancement provides a non-invasive but expensive imaging technique for equivocal CT cases and detection of tumor extension to adjacent structures and major vessels. Scintigraphy provides valuable information in selected cases which need localization of tumor side or detection of extra-adrenal tumors or metastases. PET is a new non-invasive technique with the advantage of the whole body scan which is promising and could become part of the routine evaluation of adrenal masses.
Management of adrenal masses depend on data collected on evaluation and includes conservative management and adrenalectomy.
Conservative management is recommended for non-functional benign tumors and patients with poor operative risk also medications should be given for pre-operative preparation.
Adrenalectomy is treatment of choice for patients who were proved to have surgical lesions on evaluation.
Open adrenalectomy is recommended in carcinomas and large tumors and can be performed via anterior, lateral or posterior approach.
Laparoscopic adrenalectomy is now considered the gold standard in adrenal surgery for small benign masses based in its safety, short hospital-stay time and recovery time and low complication rate. It can be prformed transperitoneally or retroperitoneally.