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Simultaneous occurrence of an intracranial meningioma and a growth hormone (GH)-producing pituitary adenoma is exceedingly rare, as is coexistence of an empty sella and acromegaly. We report all these rare entities in the same patient. We evaluated the role of inferior petrosal sinus sampling for lateralisation of an adenoma in this patient.

By means of high-resolution CT, pituitary stalks and glands were demonstrated in 189 normal subjects and in six patients with microadenomas. In the horizontal view and in reconstructed coronal and sagittal projections, the normal stalks and glands showed homogeneous enhancement with the contrast medium. On metrizamide CT, the stalks and glands were demonstrated in high-density areas as a "defect". The detection-rate of the stalks and glands was more than 93.6% in all dimensions on enhanced CT and 100% on metrizamide CT. On reconstructed sagittal projections, there was a tendency for the glands to decrease in size with advancing age. Under the age of 29, especially in females, most of the glands were demonstrated as an oval area that filled the sella turcica. After the age of 50, the gland frequently was flattened with enlargement of the CSF space within the sella turcica, giving an appearance reminiscent of the "empty sella". Of six patients with microadenomas, five presented the appearance of oval gland, and one showed visualization of CSF space in the anterosuperior portion of the sella turcica. On reconstructed coronal projections, the angle of inclination of stalks was 1.5 +/- 1.2 degrees in normal subjects and 9.3 +/- 2.4 degrees in patients with microadenomas.

Suspected lesions in and around the sella were examined by CT in 129 cases. The diagnostic accuracy and various technical aspects of the method are described. The mean attenuation and enhancement after administration of contrast material are evaluated in craniopharyngiomas, chromophobe adenomas, meningiomas, aneurysms, dermoid cysts, an arachnoid cyst and a glioma. the choice of collimator and its use in relation to sellar dimensions, particularly the sellar depths, are emphasized.

The etiology to the empty sella syndrome (ESS) is not known. Increased intracranial pressure (ICP) has been suggested to be one of the possible causes. In the present study the CSF circulation was analyzed in 48 subjects with ESS with gamma cisternography, pneumoencephalography (PEG) and computed tomography (CT). In 80% of the subjects the CSF circulation was retarded with convexity block which was combined with widened CSF transport pathways and basal cisterns. These findings were corelated with the clinical signs and symptoms, most of which seemed to be related to the impaired CSF circulation (i. e. impaired memory, balance disturbances, cerebellar ataxia, papilledema, hypertension and pituitary disorders). Headache, psychiatric symptoms, visual field defects and obesity, however, were not related to the impaired CSF circulation. It is concluded that impaired CSF dynamics leading to intermittent increase of ICP has a major impact on the development of the ESS and that most of the patients' complaints are related to this disturbance. Thus it is important to obtain information of the CSF dynamics concurrent with the diagnosis of ESS. For this purpose PEG or CT may be used as the first examination. Moreover, the patient should be examined at least every second year for symptoms and signs of progressive impairments of the CSF circulation.

The occurrence of empty sella was studied on 450 pneumoencephalograms. It was not sex dependent, and seemed to be an acquired condition increasing in frequency with age. Empty sella was found in 10% of subjects with otherwise normal encephalograms. The frequency was higher in persons with communicating hydrocephalus (32%), hormoneproducing pituitary tumors (33%) and increased intracranial pressure due to cerebral tumors (18%). In all these subjects empty sella was often accompanied by demineralization and erosion of the sella turcica. Independent of the lumbar pressure, empty sella was most often found in patients with communicating hydrocephalus with only moderately high ventricle index and comparatively increased volume of the third ventricle. Empty sella was also frequent among patients with temporal tumors (32%) causing deformation and displacement of the third ventricle but in whom signs of increased intracranial pressure were lacking. The disturbed anatomy of the third ventricle possibly explains the higher frequency of empty sella in association with these tumors compared to other supratentorial tumors. altogether, these findings indicate that disturbance of the cerebrospinal fluid (CSF) circulation, especially in the third ventricle, with or without established increase of the intracranial pressure, plays an important role in the etiology of empty sella. This is further substantiated by the demonstration that the type of intrasellar herniation could be related to the position of the third ventricle. Neither the type of herniation nor the form of the sella could be related to the presence or absence of a co-existing intracranial tumor or to the location of the tumor.

A retrospective review of twenty-five normal MRI brain studies performed with the spin-echo technique focused special attention on the ventricular and extraventricular cerebrospinal fluid (CSF) and revealed unique signal intensity characteristics in the two locations. In addition, MRI studies of ten patients with abnormal extraaxial fluid collections either missed with CT or indistinguishable from CSF on CT images were also analyzed. MRI is more sensitive when compared to CT in evaluating the composition of CSF. Unique signal intensity characterizes the two major CSF compartments and presumably reflects their known but subtle difference in protein concentration (10-15 mg%). Normal variant or abnormal developmental fluid collections can be better characterized with MRI than with CT. These preliminary observations are offered in view of their implications for patient management and suggest further investigation.

The Artronix 1,100 head scanner is a promising unit which allows reconstitution of the images in coronal and sagittal planes from the axial slice. The clinical usefulness of coronal and sagittal images thus obtained is illustrated and discussed.

In the last 3 years 86 patients were referred for suspected primary intrasellar pathology. Two of them had coexisting pituitary adenoma and partial empty sella. This situation has been diagnosed pre-operatively thanks to CT Iopamidol cisternography. The pre-operative diagnosis of this common anatomic condition allows safer operations, preventing intra-operative CSF fistulas.