Pituitary Gland Height Research Articles

Prospective assessment of pituitary size and shape on MR imaging after suppressive hormonal therapy in central precocious puberty.

The diagnostic significance of an enlarged pituitary gland regarding both shape and size parameters on MR imaging has previously been demonstrated in children with central precocious puberty. This study was designed to assess changes in these parameters following successful suppressive therapy of central precocious puberty with the gonadotropin-releasing hormone (GnRH) analogue. Twelve girls (mean age 7.3 years) with central precocious puberty were prospectively enrolled in our study protocol. Sagittal and coronal MR images of the pituitary region were obtained in all patients before treatment and after at least 6 months of GnRH analogue therapy (mean 18.0 months). Parameters measured included pituitary gland height, length, width, sagittal cross-sectional area, and volume. All patients had excellent clinical response to treatment with arrest of secondary sexual development, normalization of serum estradiol levels, and complete obliteration of the LH response to diagnostic GnRH stimulation. No significant change occurred in any pituitary size or shape parameter following GnRH analogue therapy. Favorable clinical response to GnRH analogue therapy in central precocious puberty is not accompanied by significant a change in pituitary gland size and shape.

Evaluation of Empty Sella in Patients with Cerebral Arteriovenous Malformations

To evaluate the incidence of empty sella in patients with cerebral arteriovenous malformations we retrospectively evaluated the pituitary gland height (PGH) on midsagittal T1 -weighted images in 216 patients with cerebral AVM (37.5% female, 62.5% male, mean age 33.4). Complete empty sella was defined as PGH<2 mm and partial empty sella as PGH<3 mm. Empty sella in patients with cerebral AVMs was analysed on the basis of nidal size, nidal location and age. We compared our results with those found in a normal population. Mean PGH in our patient population was 3.96 mm (range 1–9 mm). 3.4 mm in males and 4.8 mm in females. The overall incidence of empty sella was 41.2% (89/216). Empty sella occurred in 32% (48/150) of patients less than 40 years old and 62% (41/66) of patients over 40. The distribution of mean PGH values in AVM patients grouped by age was lower than but parallel to the distribution in normal PGH values. A statistically significant increased incidence of empty sella was found with cortical AVM location (48%; 69/144, p<0.0001), and nidal size> 3 cm (60%; 75/125, p<0.0001). Our results indicate that empty sella occurs more frequently in patients with cerebral AVM especially with a cortical location or a nidus greater than 3 cm. We conjecture that this may be related to altered CSF flow dynamics in these patients. Further studies may explain the higher incidence of empty sella in patients with cerebral AVM.

Pituitary gland enlargement secondary to dural arteriovenous fistula in the cavernous sinus: appearance at MR imaging.

To evaluate pituitary gland size in cases of dural arteriovenous (AV) fistula in the cavernous sinus and to correlate the size with the degree of AV fistula. Magnetic resonance images in 21 patients with angiographically proved dural AV fistula of the cavernous sinus were retrospectively reviewed. In four patients, findings obtained before and after embolization therapy were compared. The 21 patients were divided into group 1 (severe AV fistula) and group 2 (moderate or mild AV fistula). The superior contour of the pituitary gland was convex or flat in group 1 and flat or concave in group 2. The mean height of the pituitary gland was 9.4 mm +/- 1.5 (standard deviation) in group 1 and 6.7 mm +/- 1.2 in group 2 (P = .0002). After embolization therapy, pituitary gland height decreased and signal intensity voids improved in the four patients and no AV fistula was observed in three. In cases of severe dural AV fistula in the cavernous sinus, the pituitary gland is enlarged, which should not be misdiagnosed as pathologic.

MR of the pituitary in patients with Prader-Willi syndrome: size determination and imaging findings.

Prader-Willi syndrome (PWS) is an unusual genetic disorder characterized by short stature, obesity, hypogonadism, hypotonia, cognitive impairment, and dysmorphic facies. There is an interstitial deletion of the proximal long arm of chromosome 15 in about 70 % of patients. Some of these clinical features suggest a central hypothalamic/pituitary dysfunction, and recent investigations have demonstrated a marked impairment in spontaneous growth hormone (GH) secretion. We studied 15 GH-deficient PWS patients by magnetic resonance imaging (MRI) to determine whether there was a diminution in the gross morphological size of the anterior pituitary gland, the site of GH synthesis. We also set out to catalog the pertinent imaging findings in this patient population. Our results indicate that this is the first report documenting pituitary size by MRI in PWS patients. No statistically significant difference was found in the height of the anterior pituitary gland in PWS patients compared with either normal children or children with isolated GH deficiency. An interesting imaging finding is that three of 15 patients (20 %) demonstrated complete absence of the posterior pituitary bright spot (PPBS), and a fourth patient demonstrated a small PPBS. These observations reflect an objective physiologic disturbance in the hypothalamus. The clinical and radiologic implications of these findings are discussed.

MR measurement of normal pituitary gland height on midsagittal section: age and sex differentiation

MR measurement of normal pituitary gland height on midsagittal section: age and sex differentiation

Height of normal pituitary gland as a function of age evaluated by magnetic resonance imaging in children

MR anatomy of hypothalamo-hypophyseal axis is well established. However data about pituitary gland height (PGH) in children are sparse. A retrospective study was therefore performed in 60 children (30 boys and 30 girls) aged from 8 days to 21 years. All these children had MR for various neurological diseases. Patients with hypothalamo-hypophyseal disease and intracranial hypertension were excluded. The PGH was measured on a strict midline sagittal T1 weighted scan 3 to 7 mm thick. A positive linear correlation was found in children aged from 1 year to puberty followed by a plateau. In the first year of life a negative linear correlation was found. A positive linear correlation was found between PGH and statural height as well.

In VivoAssessment of Pituitary Gland Volume with Magnetic Resonance Imaging: The Effect of Age*

We used sagittal and coronal T1 weighted magnetic resonance images, at 1.5 Tesla, to measure the height, width, length, and cross-sectional area and to generate two estimates of pituitary gland volume in 35 normal volunteers aged 26-79 yr (19 females and 16 males). Subjects over 50 yr of age had significantly smaller pituitary gland height (P = 0.03), area (P = 0.04), and volume (P = 0.04) than those under 50 yr (by two-tailed t test). Overall, age was negatively correlated with pituitary volume (V1: r = -0.51; P = 0.003; V2: r = -0.47; P = 0.008), area (r = -0.43; P = 0.009), and height (r = -0.46; P = 0.005), but not with pituitary length or width. There were no statistically significant differences in pituitary size between men and women (by two-tailed t test). These findings suggest that pituitary gland height provides a good single measure for the assessment of pituitary gland size and that age must be controlled for in studies of pituitary gland size.

Height of Normal Pituitary Gland on MR Imaging

Measurement of the pituitary height was performed on magnetic resonance (MR) images of 213 subjects with no known or suspected pituitary and/or hypothalamic disorders. Midsagittal, T1-weighted images were used for measurements and mean heights in each age and sex group were obtained. In the 10 to 69 year range, the pituitary heights were greater in females than in males. The groups of 0-9 years of both genders showed the minimum mean pituitary height. The maximum of the mean height was observed in the 10 to 19 year age groups of both genders. The height gradually decreased with increasing age after age 20 years. There were no subjects with a height of greater than or equal to 9.0 mm in females or greater than or equal to 8.0 mm in males. There was a marked discrepancy between MR and autopsy findings in the older subjects, probably related to the upward concavity that is often encountered in the aged gland. Because of this concavity, the midsagittal MR measurement will induce underestimation of the whole gland.

High resolution computed tomography of the post partum pituitary gland.

Eight volunteer post partum female patients were examined with high resolution computed tomography during the week immediately after delivery. All patients received high dose (40-70 gm) intravenous iodine contrast administration. The scans were examined for pituitary gland height, shape and homogeneity. All of the patients had enlarged glands by the traditional standards (i.e. gland height of 8 mm or greater). The diaphragma sellae in every case bulged upward with a convex domed appearance. The glands were generally inhomogeneous. One gland had a 4 mm focal well defined area of decreased attenuation. Two patients who were studied again months later had glands which had returned to "normal" size. The enlarged, upwardly convex pituitary gland appears to be typical and normal for the recently post partum period.