MRI of pituitary adenoma with extensive amyloid formation

We report a patient with a pituitary adenoma with extensive amyloid formation. T2-weighted MRI was most characteristic for amyloid deposition. Received: 30 July 1998 Accepted: 20 October 1998     

Escalated median dose for pituitary macroadenomas using intensity-modulated radiation therapy.

Three-dimensional conformal radiotherapy (3D CRT) has become an established treatment for pituitary macroadenomas. This study is an investigation into the possible dosimetric advantages of intensity-modulated radiotherapy for such critically located tumors. Three consecutive patients with pituitary macroadenoma previously treated with 3D CRT were replanned with inverse-planned IMRT using Helax-TMS (V.6.0, Helax AB, Uppsala, Sweden. Fusion of computed tomography (CT) with postoperative magnetic resonance imaging (MRI) was performed within the planning system to define the gross tumor volume (GTV), planning target volume (PTV), and normal structures including the optic chiasm. Dose-volume histograms (DVHs) for the 3D CRT plans were then compared with those of the corresponding prospective IMRT plans. Both techniques maintained critical structure doses below tolerance levels while maintaining a minimum dose of 45 Gy to 100% of the PTV. While IMRT plans deliver consistently more heterogeneous dose distributions to the PTV, the median PTV dose is elevated in the IMRT plans compared with the 3D CRT plans. For critically located tumors like these pituitary macroadenomas, IMRT allows escalation of the median dose to the tumor without an accompanying loss in critical structure sparing or creating unacceptable cold spots within the PTV.     

Recurrent pituitary adenomas after surgical resection: the role of radiation therapy

Postoperative radiation therapy for pituitary adenomas is usually reserved for extensive lesions or those that are incompletely resected. Nineteen patients who received external beam radiation as a salvage procedure after recurrence following surgery alone for pituitary adenomas were studied. At recurrence, nine patients underwent reexcision. All 19 patients underwent external beam irradiation for salvage. Within a median follow-up time of 11.8 years from the time of surgical failure, two patients have died of progressive adenoma, two are alive with disease progression, eight are alive without disease progression, and seven have died of intercurrent disease. The 5-, 10-, 15-, and 20-year overall actuarial (and progression-free) survival rates were 79% (90%), 62% (90%), 44% (80%), and 44% (53%), respectively. Dose of radiation, suprasellar extension at the time of surgical failure, and histologic findings had no bearing on prognosis. One patient developed a radiation-induced brain necrosis that was successfully resected. Radiation therapy can be an effective salvage modality for recurrent pituitary adenomas after surgical failure.     

Metastases from a pituitary adenoma: MRI

Few cases of pituitary adenoma with metastases have been reported. We report a case with histologically benign intracranial and cauda equina metastases. We compare it to the others in the literature. Received: 30 March 1998 Accepted: 22 January 1999     

Concomitant pituitary adenoma and Rathke's cleft cyst

We reviewed the clinical, radiological and surgical findings in patients with both pituitary adenoma and Rathke's cleft cyst. We retrospectively selected patients with both lesions from the 374 patients in whom a sellar/juxtasellar lesion was detected on MRI at 1.5 tesla. All patients received intravenous contrast medium. Concomitant pituitary adenoma and Rathke's cleft cyst were found in eight patients (2.1 %). The frequency of the combination was 3.5 % of pituitary adenomas and 11 % of Rathke's cleft cysts. Symptoms were always due to the adenoma, secreting adrenocorticotrophin in two patients and growth hormone in six. The adenoma was larger in five patients, and the cyst in three. The cysts gave variable signal. The adenoma was adjacent to the cyst in seven patients, and enclosed it in the other patient. As a result of experience with MRI, concomitant pituitary adenoma and Rathke's cleft cyst are now known not to be as rare as thought previously. When a nonenhancing cyst-like structure is demonstrated in a patient with pituitary adenoma, the possibility of a coexisting Rathke's cleft cyst should be considered. Received: 23 March 2000/Accepted: 12 July 2000     

侵袭性垂体腺瘤1例

患者女,46岁。因反复鼻塞1年,加重伴嗅觉减退、耳闷3月。患者于1年前无明显诱因下出现鼻塞,呈双侧,冷热刺激后加重,偶流清水涕,量不多,无涕中带血,近3月加重,并伴嗅觉减退,夜间打鼾,偶伴右耳闷,非持续性,无头晕     

MRI of a pituitary cryptococcoma simulating an adenoma

We describe a rare pituitary cryptococcoma in an immunocompetent patient, with radiological features similar to those of a pituitary macroadenoma. Although unusual, it should be added to the list of differential diagnosis of pituitary masses. Contrast enhancement of adjacent meninges differentiated the lesion from an adenoma.     

Trends in the radiological study of pituitary adenoma

Summary The time and place for the use of plain films of the skull, arteriography and venography, CT with and without contrast enhancement, and metrizamide cisternography as a replacement for air encephalography, fot the diagnosis of the various kinds of pituitary adenomas is discussed in conjunction with a report of the experience with eight pituitary adenomas.Presented at the 9th Congress of the European Society of Neuroradiology, Brussels, Belgium, 12 September 1980     

Hemorrhage in pituitary adenoma: correlation of MR imaging with operative findings

The aim of this study was to correlate MR imaging and operative findings of hemorrhage in pituitary macroadenomas. We retrospectively reviewed MR images of 113 surgically proven pituitary adenomas. All patients were examined on a 1.5-T MR system. The intensity of intratumoral cystic cavities was correlated with operative findings. In 15 patients with pituitary apoplexy, we determined relationship between interval of MR examination after apoplectic event and MR signal intensity. In 8 patients with repeated preoperative MR examination, we evaluated sequential changes of intratumoral hemorrhage. There were 54 cavities at surgery: 52 were hemorrhagic and 2 were nonhemorrhagic. Twenty-nine of 52 hemorrhagic cysts demonstrated high/low signal (H/L) fluid–fluid levels on T2-weighted image (T2WI). In 19 of them, two components could be separately seen at operation: the supernatant high-intensity area represented xanthochromic fluid, and the dependent low-intensity area represented liquefied hematoma. The H/L fluid–fluid level was observed predominantly in hematomas on MR images obtained after longer intervals. In patients with repeated MR examination, follow-up MR imaging revealed additional hemorrhage or new formation of fluid–fluid levels. It was surprising that 12 of 14 cysts preoperatively judged as nonhemorrhagic in fact contained hemorrhagic components. The preoperative MR images are well correlated to the operative findings in hemorrhagic pituitary macroadenomas. It proved that 52 of 54 cystic cavities had hemorrhagic component. Received 1 July 1997; Revision received 12 November 1997; Accepted 9 December 1997     

Treatment of recurrent chordomas by percutaneous ethanol injection therapy and radiation therapy

We report a case of recurrent sacral chordomas that have been successfully controlled by the combination therapy of percutaneous ethanol injection therapy (PEIT) and radiation therapy in a 71-year-old man. PEIT may be one of the adjuvant therapies for recurrent chordomas.     

Acute hyperthermia following stereotactic radiosurgery for pituitary adenoma

A 71-year-old male presented with a large pituitary adenoma with superior extension into the optic chiasm and suprasellar cistern. He was treated with stereotactic radiosurgery to a dose of 16 Gy. Approximately 1 h after radiosurgery he developed fever; his temperature peaked at 105.1 degrees F and normalized about 20 h later. This case demonstrates that acute hyperthermia is a potential complication following high dose stereotactic radiosurgery for large pituitary tumours.     

Magnetic resonance imaging of the normal pituitary gland and pituitary adenoma: preliminary experience with a resistive magnet

Magnetic resonance (MR) imaging was performed in fifty normal pituitary glands, ten pituitary microadenomas, and twelve adenomas with extrasellar extension using a 0.15 Tesla resistive magnet. The average height of normal glands was 5.6 +/- 1.2 mm, whereas that of microadenomas was 6.8 +/- 1.0 mm. The superior surface and internal texture of these conditions were well delineated. Adenomas that showed extrasellar extension together with surrounding structures were well demonstrated on sagittal and coronal scans. It can be expected that with further technical developments MR imaging will play an important role in the clinical management of pituitary adenomas.     

Treatment of Cushing's disease with adrenal blocking drugs and megavoltage therapy to the pituitary.

Eighteen patients with Cushing's disease were seen over a 40-month period and considered for treatment by pituitary irradiation and adrenal blocking drugs. Fourteen patients entered the study and each received megavoltage therapy to give a mean dose of 4600 rad to the pituitary over 31 days. Each patient was treated for one (two patients) or two (12 patients) years with one or both of the adrenocortical enzyme inhibitors, metyrapone or aminoglutethmide to suppress cortisol secretion. Doses were adjusted to maintain urinary free cortisol secretion below 300 nmol/24 h. One patient failed to complete the trial. Normal urinary free cortisol excretion and plasma cortisol concentration were maintained after treatment in eight of the remaining 13 patients after therapy. Only one patient required cortisol replacement and normal menstrual function was restored in five of the six women. The remaining five patients relapsed and four were subsequently treated by total adrenalectomy. It was noted that the patients who responded to treatment were substantially younger than the therapeutic failures. It is suggested that this treatment is most useful in the management of younger patients.     

MR findings of subarachnoid dissemination of a pituitary adenoma

Although pituitary adenoma is a benign tumour, subarachnoid dissemination occurs rarely. We describe a case of pituitary adenoma with subarachnoid dissemination. After the third operation for pituitary adenoma, an extraaxial mass was demonstrated on MR images. On T1 and T2 weighted images, the signal intensities of the extraaxial mass were similar to those of the primary pituitary adenoma. On dynamic contrast T1 weighted images, the time-intensity curve of the extraaxial mass, which showed early and persistent signal intensity, was also similar to that of the primary pituitary adenoma. These MR findings are considered to reflect the similar vascularity and stroma of the extraaxial mass and the primary pituitary adenoma.     

伽马刀结合手术切除治疗垂体腺瘤的疗效分析

目的单纯伽马刀治疗及与显微神经外科手术结合治疗垂体腺瘤的疗效分析。方法回顾性分析经伽马刀或显微神经外科手术结合伽马刀治疗的137例垂体腺瘤患者资料,其中单纯伽马刀治疗95例,手术结合伽马刀治疗42例,随访6～64个月,对治疗后的临床症状、内分泌结果及MRI表现进行统计分析。结果137例患者中,临床症状缓解者124例（90．5％）,其中手术后行伽马刀治疗患者37例,只行伽马刀治疗患者87例。治疗后功能性垂体腺瘤内分泌激素水平恢复正常或降低者96例（93．2％）。MRI复查瘤体缩小者118例（86．1％）。结论对于垂体腺瘤来说,伽马刀是一种积极有效的治疗手段;单纯伽马刀或与显微神经外科手术结合治疗是治愈绝大多数垂体腺瘤患者的最佳方案。