Top PDF Sequential MR enhancement pattern in normal pituitary gland and in pituitary adenoma

Sequential MR enhancement pattern in normal pituitary gland and in pituitary adenoma

Sequential MR enhancement pattern in normal pituitary gland and in pituitary adenoma

The purpose of our work was to assess the pattern of enhancement in the normal pituitary gland and pituitary adenomas using an imageacquisition process with increased temporal resolution[r]

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CT surgical correlation in pituitary adenomas: evaluation in 113 patients

CT surgical correlation in pituitary adenomas: evaluation in 113 patients

The location of the normal pituitary gland could not be determined by attenuation characteristics ; only in the presence of infundibulum displacement contralateral to an adenoma or a dis[r]

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Rathke cleft cysts: correlation of enhanced MR and surgical findings

Rathke cleft cysts: correlation of enhanced MR and surgical findings

In pituitary adenomas, the position of the normal pituitary gland is usually superior to or surrounding the tumor, whereas the position is highly variable in Rathke cleft cysts; cyst wal[r]

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MR imaging of pituitary adenomas using a prototype resistive magnet: preliminary assessment

MR imaging of pituitary adenomas using a prototype resistive magnet: preliminary assessment

As in the case of the normal pituitary gland, on IR images, most pituitary adenomas exhibited a signal intensity less than that of the pons, markedly less than clival or dorsum sellae bo[r]

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Pituitary Adenomas: Early Postoperative MR Imaging After Transsphenoidal Resection

Pituitary Adenomas: Early Postoperative MR Imaging After Transsphenoidal Resection

periphery of the gelatin foam implant demonstrated a circular rim of contrast enhancement, which was seen in all cases except one. This patient underwent postoperative MR imaging 5 days after surgery. Steiner suggested this peripheral enhancement was very likely caused by granulation tissue, which was seen several months after surgery. Peripheral en- hancement in our study focused on early postop- erative findings. A thin enhancing rim, as seen on CT, has been referred to as a persistent tumor cap- sule (9, 12, 13). Dina et al (2) also reported this peripheral enhancing rim in three of 10 patients in the early postoperative period, and it could not be determined on a single imaging study whether this tissue represented a residual tumor, tumor capsule, or pituitary gland. Dina et al (2) suggested that on follow-up studies, this tissue assumed a more nor- mal pituitary size and shape within the confines of the sella 4 to 9 months later. In our patients with peripheral rim enhancement, there was no case that showed increased size on follow-up MR images or elevation of hormone level on follow-up laboratory studies. In addition, on follow-up MR images, pe- ripheral rim enhancement disappeared and normal gland reexpanded in the pituitary fossa. Therefore, we regarded this peripheral rim enhancement as
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Clinical Reasoning: A 41-year-old man with thunderclap headache

Clinical Reasoning: A 41-year-old man with thunderclap headache

In some studies, 60%–80% of cases of apoplexy have no clear precipitant. 4 The most common precipitating factors include major surgery, clotting disorders, estrogen therapy, dopamine agonist therapy, head trauma, pregnancy, and radiotherapy. 2 Even without a clear precipitant, pituitary apoplexy often manifests in a recognizable manner. The most frequent symptom is severe sudden headache—usually bifrontal or suboccipital 5 —and it is observed in approximately 80% of patients. 3 Visual disturbances occur in more than half of patients and ocular motor palsies affect up to 50%–60% of patients due to damage of cranial nerves III, IV, and VI. 3 Because of the superior orientation of CN III within the cavernous sinus, it is most likely to be affected in the acute phase of pituitary apoplexy and thus can mimic the pre- sentation of a posterior communicating artery aneurysm. Other symptoms include nausea, vomiting, photophobia, and altered mental status. 2 Patients can also present with menin- gismus due to blood in the suprasellar cisterns that leaks into the subarachnoid space. 5
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Silent Crooke’s cell corticotroph adenoma of the pituitary gland presenting as delayed puberty

Silent Crooke’s cell corticotroph adenoma of the pituitary gland presenting as delayed puberty

The adenoma in our patient was also associated with a cyst consistent with Rathke’s cleft cyst (RCC). The coexistence of adenoma and RCC is now known not to be as rare as thought previously (14, 15). Small, asymptomatic RCCs concomitant to adenoma are more frequent and are usually found as incidental post-mortem finding and the commonest association was with prolactinoma and the least frequent was ACTH-secreting adenomas (16). Our patient had an initial clinical course suggestive of CDGP, but was subsequently identified to have a CCA that is currently biochemically and clinically silent.
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A patient with a germline SDHB mutation presenting with an isolated pituitary macroprolactinoma

A patient with a germline SDHB mutation presenting with an isolated pituitary macroprolactinoma

Symptomatic pituitary adenomas occur with a prevalence of approximately 0.1% in the general population. It is estimated that 5% of pituitary adenomas occur in a familial setting, either in isolated or syndromic form. Recently, loss- of-function mutations in genes encoding succinate dehydrogenase subunits (SDHx) or MYC-associated factor X (MAX) have been found to predispose to pituitary adenomas in co-existence with paragangliomas or phaeochromocytomas. It is rare, however, for a familial SDHx mutation to manifest as an isolated pituitary adenoma. We present the case of a pituitary lactotroph adenoma in a patient with a heterozygous germline SDHB mutation, in the absence of concomitant neoplasms. Initially, the adenoma showed biochemical response but poor tumour shrinkage in response to cabergoline; therefore, transsphenoidal surgery was performed. Following initial clinical improvement, tumour recurrence was identified 15 months later. Interestingly, re-initiation of cabergoline proved successful and the lesion demonstrated both biochemical response and tumour shrinkage. Our patient’s SDHB mutation was identified when we realised that her father had a metastatic paraganglioma, prompting genetic testing. Re-inspection of the histopathological report of the prolactinoma confirmed cells with vacuolated cytoplasm. This histological feature is suggestive of an SDHx mutation and should prompt further screening for mutations by immunohistochemistry and/or genetic testing. Surprisingly, immunohistochemistry of this pituitary adenoma demonstrated normal SDHB expression, despite loss of SDHB expression in the patient’s father’s paraganglioma.
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MR Imaging of the Pituitary Gland and Postsphenoid Ossification in Fetal Specimens

MR Imaging of the Pituitary Gland and Postsphenoid Ossification in Fetal Specimens

pituitary gland was also demonstrated in fetal specimens younger than 21 weeks of gestation in this study. Histologic changes within the anterior pituitary lobe with increasing amounts of endoplas- mic reticulum, high-level synthesis of pituitary protein, and the higher fraction of bound water molecules due to hormonal secre- tion are thought to cause hyperintensity of the anterior lobe on T1WI. 20 Such hormonal hyperactivity was also observed in

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Lesson J- Introduction to Endocrine System.pptx

Lesson J- Introduction to Endocrine System.pptx

Secreted by Pituitary Gland • TRH (thyrotropin-releasing hormone) = stimulates release of TSH from ant. pituitary[r]

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Volumetric Measurement for Comparison of the Accuracy between Intraoperative CT and Postoperative MR Imaging in Pituitary Adenoma Surgery

Volumetric Measurement for Comparison of the Accuracy between Intraoperative CT and Postoperative MR Imaging in Pituitary Adenoma Surgery

In this study, we divided patients into 2 groups, the GTR group and the STR group, and assessed in a quantitative manner whether the use of iCT could replace iMR imaging without compromising the extent of the tumor resection of pituitary macroadenomas. To quantitatively define the resection status, the volume of residual tumor tissue was assessed and calculated in the iCT, pre-, and postoperative 1.5T MR images, respectively, by using the software OsiriX (www.osirix- viewer.com) We determined the preoperative volume as volume A, the intraoperative volume as B, and postoperative volume as C and to minimize the calculating bias, volumes A, B, and C were the averages individually computed from the axial, sagittal, and coronal images. In addition, A 1 , B 1 , and C 1 stood for the tumor volumes of patient 1; A 2 ,
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Hypersecretion of ACTH and PRL from pituitary adenoma in MEN1, adequately managed by medical therapy

Hypersecretion of ACTH and PRL from pituitary adenoma in MEN1, adequately managed by medical therapy

not shown). Contrast-enhanced magnetic resonance imaging (MRI) of the pituitary identified a pituitary tumor with invasion of both right and left cavernous sinuses, suggesting that the pituitary tumor may be single adenoma and not multiple (Fig.  2B). Taking his family history and these results into account, he was strongly suspected of having MEN1. As described below, the diagnosis of MEN1 was eventually confirmed by genetic analysis. Although we could not measure urinary cortisol excretion, elevation of plasma ACTH levels and bilateral adrenal swelling suggested an overproduction of ACTH. Therefore, we performed further examination on the ACTH–adrenal axis. After oral administration of dexamethasone at a dose of 0.5 mg, midnight serum
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The Diabetogenic Hormone of the Pituitary Gland

The Diabetogenic Hormone of the Pituitary Gland

The normal fasting level of the blood glucose of toads kept on a black background was significantly higher than that of toads on a white background.. After hypophysectomy the blood sugar[r]

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Pituitary mass in pregnancy - unlikely to be an adenoma?

Pituitary mass in pregnancy - unlikely to be an adenoma?

Despite its rarity a high index of suspicion is required. Factors which increase suspicion of LH include context (e.g. pregnancy or puerperium), atypical pattern of hormone deficiency (e.g. ACTH deficiency occurring with normal LH/FSH and GH reserve) and/ a clinical presentation inconsistent with the size of the pituitary mass on imaging. Radiological features can be difficult to interpret with absolute certainty. Experienced endocrinologists should be familiar reviewing these images and be skeptical when findings are not typical of those seen in a pituitary adenoma [19].
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MR of the pituitary gland postsurgery: serial MR studies following transsphenoidal resection

MR of the pituitary gland postsurgery: serial MR studies following transsphenoidal resection

The following were recorded : height of t he p itu itary mass, relationship to the optic chiasm , enhancement , visualization of t he pituitary gland and sta lk , and the appearance of t[r]

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Parasellar T2 Dark Sign on MR Imaging in Patients with Lymphocytic Hypophysitis

Parasellar T2 Dark Sign on MR Imaging in Patients with Lymphocytic Hypophysitis

In all patients with LYH and pituitary adenoma, the plasma con- centrations of ACTH, GH, PRL, LH, FSH, TSH, cortisol, free T4, and testosterone were measured. Provocative tests were performed as fol- lows: for TSH and PRL, after a bolus injection of 500 mg of TSH- releasing hormone; for LH and FSH, 100 mg of gonadotropin-releas- ing hormone; for GH, 100 mg of GH-releasing hormone or 0.1 U of regular insulin per kilogram of body weight; and for cortisol, 0.25 mg of ACTH or 0.1 U of regular insulin per kilogram of body weight. Multiple blood samples were collected to measure plasma hormone concentrations before and for up to 120 minutes after the injections. In patients with LYH except for cases 2, 8, and 13, plasma vasopressin concentrations were determined by radioimmunoassay, and plasma and urinary osmolarities were measured before and after 4 – 8 hours of water deprivation. In cases 9, 11, 21, and 22 of patients with pitu- itary adenoma, hormonal examination was done for the posterior lobe by using the same method.
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Normal pituitary gland: 2  Microscopic anatomy CT correlation

Normal pituitary gland: 2 Microscopic anatomy CT correlation

To determine the effects of contrast infusion during CT, density measurements of lucent and dense areas in the anterior lobes of 26 normal contrast-enhanced pituitary glands in vivo were[r]

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Assessment of Hemorrhage in Pituitary Macroadenoma by T2* Weighted Gradient Echo MR Imaging

Assessment of Hemorrhage in Pituitary Macroadenoma by T2* Weighted Gradient Echo MR Imaging

Intraparenchymal large hematomas appear as several dif- ferent patterns regardless of the age of the hematoma. The most common appearance of a “dark rim,” “low signal inten- sity rim,” or “peripheral signal intensity loss” can be explained as the “boundary effect,” based on differences in magnetic susceptibility at the border of tissues and by the deoxygenation of blood occurring in the interdigitation of blood and tissue at the periphery of the lesion. 16 The presence of perilesional he- mosiderin in chronic hematoma causes the “rim” appearance on T2*-weighted GE MR images. Our study found that a “dark rim” was the most common appearance of intratumoral hem- orrhage in pituitary macroadenoma.
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Normal pituitary gland: 1  Macroscopic anatomy CT correlation

Normal pituitary gland: 1 Macroscopic anatomy CT correlation

S.-A, Schematic coron al section through mid part of pituitary gland invo lves anteri or part of posterior lobe arrowheads , parts of par intermed ia short arrows , and posteri or part[r]

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Normal MR appearance of the pituitary gland in the first 2 years of life

Normal MR appearance of the pituitary gland in the first 2 years of life

The pituitary gland images of the 100 children were evaluated by two of the authors (L.E.L., R.B.D.). The eval- uations were carried out by the authors independently, with subsequent discussion, as necessary, to agree on the grade assigned to minimize observation variation (11). The readers graded all cases without prior knowledge of the age of the patient. Images were assessed according to the following criteria: (a) the signal intensities of the ante- rior and posterior portions of the gland as seen on the T1-weighted sagittal images were graded from 1 to 3: 1 being gray matter; 2, myelinated white matter in the pos- terior corpus callosum (in children older than 4 weeks) or higher than gray matter but lower than subcutaneous fat (in children younger than 4 weeks); and 3, subcutaneous fat; (b) the shape of the superior surface of the pituitary gland also was graded as convex, bimodal (giving the entire glad an hourglass configuration), flat, or concave; and (c) the dimensions of the pituitary gland were mea- sured directly from the images. The anterior and posterior portions of the gland were not measured separately, be- cause the small size of the gland and the relative isointen- sity of the two portions of the gland in a large number of infants precluded separate measurements of these struc- tures. The T1-weighted sagittal sequence was used to measure both the anteroposterior diameter and the height. The width was measured from either axial or coronal im- ages (Fig 3).
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