Idiopathic granulomatous hypophysitis: are there reliable, constant radiological and clinical diagnostic criterias?

Abstract

Idiopathic granulomatous hypophysitis is a rare inflammatory disease of unknown aetiology; few cases are reported. We review the clinical presentation and radiological characteristics of these cases and our own experience with three new surgical cases, to determine diagnostic criteria. MRI of three cases revealed sellar lesions extending into the chiasmatic cistern. Their shape varied, from dumbbell to spherical and elliptical. All were isointense with the brain on T1-weighted images and gave heterogeneously high signal on T2-weighted images. Contrast enhancement was homogeneous in one case and heterogeneous in another. The pituitary stalk could not be identified. There was no dural enhancement. The sphenoid sinus mucosa was thickened in two cases and normal in one.

Idiopathic granulomatous hypophysitis presenting as non-functioning pituitary adenoma: description of six cases and review of literature

“…Enhancement with contrast in IGH is quite variable and this cannot be used as a reliable distinguishing feature with pituitary adenomas. 12 Thickening of the pituitary stalk is common, as seen in two of our patients. This could be a nonspecific reaction to pituitary pathology or extension of the lesion along with the stalk.…”

Primary granulomatous hypophysitis: a case report and literature review

“…Granulomatous hypophysitis is characterized by necrotizing granulomas that are formed by collection of histiocytes, multinucleated giant cell, and variable numbers of lymphocytes and plasma cells [4,9,18,26,27]. Xanthomatous hypophysitis, the least common form of primary hypophysitis, is characterized by the presence of lipid-rich foamy histiocytes with variable numbers of lymphocytes [4,10,26,37].…”

“…Currently, MRI plays a crucial role in the diagnosis of primary hypophysitis because it has distinct advantage over CT for imaging the pituitary and sellar regional lesions. The MRI findings of primary hypophsitis include: (1) Diffuse, ill-defined, symmetrical enlargement of pituitary tissue; (2) Pituitary stalk thickened, but not deviated or unidentifiable; (3) Sellar floor usually intact; (4) Mostly isointensity with gray matter on T1 weighted image, marked homogeneous or heterogeneous enhancement by gadolinium and a strip of enhanced tissue along the dura mater (the so-called 'dural tail'); (5) Delayed complete contrast enhancement of the whole pituitary in dynamic MRI (>90 sec) [1,4,[8][9][10][11][12][29][30][31][32]. Among these unusual MRI scan findings, three imaging signs -pituitary diffuse enlargement and marked enhancement and pituitary stalk thickening, are perhaps the strongest predictor of primary hypophysitis.…”

Primary non-necrotizing granulomatous hypophysitis mimicking pituitary adenomas

“…A triangular-shaped sellar mass, an enlarged pituitary and thickened sphenoidal mucosa are the other MRI findings that can be visualized in hypophysitis cases (9,14). Pituitary stalk thickening was the most common finding and seen in 66% of granulomatous hypophysitis cases (11,8,32). All these radiological features are non-specific, which is why hypophysitis cases are generally misinterpreted as pituitary adenoma and the diagnosis is usually made postoperatively by histological examination (8,37,41).…”