Prevalence of pituitary cysts in children using modern magnetic resonance imaging techniques

A novel CHD3 variant in a patient with central precocious puberty: Expanded phenotype of Snijders Blok-Campeau syndrome?

Snijders Blok-Campeau syndrome is an autosomal dominant genetic disorder first described in 2018, mostly associated with de novo variants in the CHD3 gene that affects chromatin remodeling. This syndrome is characterized by developmental delay, speech delay, and intellectual disability, but only about 60 affected individuals have been reported to date. We report a de novo likely pathogenic CHD3 variant (c.5609G > A; p. (Arg1870Gln)) in a young female presenting with features of Snijders Blok-Campeau syndrome including speech delay, autism spectrum disorder, learning difficulties, characteristic facial dysmorphisms, and a feature not previously described in this syndrome, idiopathic central precocious puberty. Her puberty was controlled with monthly injections of a GnRH analogue. Targeted exome sequencing was negative for genes known to be responsible for central precocious puberty. Our case raises the possibility that variants in CHD3 gene may also result in central precocious puberty. Strengthening this association could expand the phenotypic spectrum of the Snijders Blok-Campeau syndrome and should be included in multigene panels for precocious puberty.

Clinical, Endocrine and Neuroimaging Findings in Girls With Central Precocious Puberty

CONTEXT

The etiology of central precocious puberty (CPP) includes a spectrum of conditions. Girls younger than age 6 years with CPP should undergo cranial magnetic resonance imaging (MRI), but it remains controversial whether all girls who develop CPP between the ages of 6 and 8 years require neuroimaging examination.

OBJECTIVE

To investigate the frequency of brain MRI abnormalities in girls diagnosed with CPP and the relationship between maternal factors, their age at presentation, clinical signs and symptoms, hormonal profiles, and neuroimaging findings.

METHODS

Data were collected between January 2005 and September 2019 from 112 girls who showed clinical pubertal progression before 8 years of age who underwent brain MRI.

RESULTS

MRI was normal in 47 (42%) idiopathic (I) scans, 54 (48%) patients had hypothalamic-pituitary anomalies (HPA) and/or extra-HP anomalies (EHPA), and 11 (10%) had brain tumors or tumor-like conditions (BT/TL), including 3 with neurological signs. Associated preexisting disorders were documented in 16. Girls with BT/TL had a higher LH peak after GnRH test (P = 0.01) than I, and those older than age 6 years had a higher craniocaudal diameter of the pituitary gland (P = 0.01); their baseline FSH and LH (P = 0.004) and peak FSH (P = 0.01) and LH (P = 0.05) values were higher than I. Logistic regression showed maternal age at menarche (P = 0.02) and peak FSH (P = 0.02) as BT/TL risk factors.

CONCLUSIONS

MRI provides valuable information in girls with CPP by demonstrating that fewer than half have a normal brain MRI and that few can have significant intracranial lesions after the age of 6, despite the absence of suggestive neurological signs.

T2 hypointense signal discovered incidentally at the posterior edge of the adenohypophysis on MRI: its prevalence and morphology and their relationship to age

PURPOSE

T2 hypointense signal at the posterior edge of the adenohypophysis (T2HSPA) on magnetic resonance imaging (MRI) is incidentally encountered. We aimed to investigate the prevalence and morphology of T2HSPA and their relationship to age.

METHODS

A total of 212 cases between 3 and 88 years old were examined. Sagittal T2-weighted image (T2WI) was evaluated for the presence of T2HSPA, which classified by its morphology into two types (belt-like or nodal). The Wilcoxon rank sum test and chi-square test were used to evaluate the differences between the groups. The T2HSPA was extracted by ImageJ software and measured as a cross-sectional area (CSA) quantitatively by threshold setting. We examined the relationship between CSA of T2HSPA and age, and Spearman's correlation coefficients were used for statistical analysis.

RESULTS

Of the 212 cases, 80 (37.7%) were identified with T2HSPA. The groups with T2HSPA were significantly younger than the groups without it (p = .01). Groups with belt-like T2HSPA were significantly younger than the groups with nodal T2HSPA (p = .01). There was a weak negative correlation between CSA of T2HSPA and age (p = .02).

CONCLUSION

T2HSPAs were incidentally detected in 37.7% of all cases, tended to be more common in younger cases, and their morphology was related to age. They seem to have little clinical significance as they tend to decrease in size with age.

Is Gadolinium Contrast Necessary for Pituitary MRI in the Evaluation of Pediatric Short Stature and Growth Hormone Deficiency?

INTRODUCTION

Short stature is a common concern that necessitates pediatric endocrinology evaluation. Growth hormone deficiency (GHD) is a commonly considered etiology. Brain and pituitary magnetic resonance imaging (MRI) with gadolinium-based contrast agents (GBCAs) is the most widely used imaging in assessing patients with GHD. Given the significant strides made in MRI technology, the need for contrast material should be reassessed.

METHOD

We performed a retrospective review of healthy patients with short stature and/or GHD who underwent brain and pituitary MRI with and without contrast to assess the added value of contrast administration.

RESULTS

227/318 identified patients underwent growth hormone (GH) stimulation testing; 28 (12.3%) with normal GH response and 62 (27.3%) with severe GHD. We found a low incidence of sellar and suprasellar pathologies. When comparing noncontrast and contrast MRI, we found perfect agreement in detecting abnormal posterior pituitary bright spots (kappa:1.0) and substantial agreement in detecting pars intermedia cysts and posterior superior sellar cysts (kappa: 0.74 and 0.71, respectively). Initially, only moderate agreement was found in detecting infundibular abnormalities (kappa: 0.51), although a revised noncontrast MRI protocol with high-resolution 3D images enabled visualization of the infundibulum.

CONCLUSION

The MRI evaluation of healthy patients with short stature and/or isolated GHD may be completed without the use of GBCAs. The slight overestimation of pituitary stalk interruption by noncontrast images can be overcome by adding newer high-resolution sequences.

Growth hormone replacement therapy: is it safe to use in children with asymptomatic pituitary lesions?

OBJECTIVES

Small pituitary cysts are commonly discovered on pediatric brain magnetic resonance imagings (MRIs), particularly in patients with growth hormone deficiency (GHD). We examined the need for operative management in children with these masses as well as the effect of growth hormone replacement (GHR) on these lesions.

METHODS

This was a retrospective review of pituitary protocol MRIs conducted in children 0-19 at a single center between April 2010-November 2020. Sex, indication for initial MRI, volume, and whether surgery was performed was determined. Records were reviewed to determine whether GHD was present and treatment with GHR documented. For patients with subsequent MRIs, volume on most recent scan was calculated.

RESULTS

Of the 101 children with cysts, 25 had laboratory-confirmed GHD and 76 did not. GHD patients had a higher mean age compared to no growth hormone deficiency (NGHD) cohort (11.2 and 8.4 years, respectively; p=0.02) and a larger proportion of males (p<0.001). The mean cyst volume on initial MRI was not significantly smaller in patients with GHD (0.063 ± 0.012 cm³) vs. those without GHD (0.171 ± 0.039 cm³, p=0.11). Of the 21 GHD patients who received GHR and had follow-up MRIs, 10 had no change in pituitary cyst size, two had cysts that shrank, and seven disappeared. The remaining two cysts enlarged an average of 0.061 ± 0.033 cm³. Zero GHR recipients required surgical intervention.

CONCLUSIONS

Small sellar cysts discovered incidentally on imaging in children are unlikely to require surgical intervention. GHR does not appear to significantly enlarge these pediatric pituitary lesions and is safe for use.

Primary Tumors of the Pituitary Gland: Radiologic-Pathologic Correlation

Primary tumors of the pituitary gland are the second most common histologic category of primary central nervous system tumors across all age groups and are the most common in adolescents to young adults, despite originating from a diminutive endocrine gland that is often described as "about the size of a pea." The vast majority of these represent primary tumors of the adenohypophysis, specifically pituitary adenomas, which can be either functional or silent with regard to hormone hypersecretion. According to the fourth edition of the World Health Organization classification of endocrine tumors, published in 2017, cellular lineage and immunohistochemical stains for pituitary hormones and/or transcription factors help with making the correct pathologic diagnosis. From a radiologic standpoint, microadenomas pose challenges for accurate detection and avoiding false-negative or false-positive results, while macroadenomas pose challenges from local mass effect on surrounding structures. Pituitary carcinoma and pituitary blastoma also arise from the adenohypophysis and are characterized by metastatic disease and infantile presentation, respectively. While primary tumors of the adenohypophysis are common, a second category comprising primary tumors of the Rathke pouch (ie, craniopharyngioma) are uncommon, and a third category comprising primary tumors of the neurohypophysis (eg, pituicytoma) are rare. The authors review all three categories of pituitary tumors, with emphasis on radiologic-pathologic correlation, including the typical neuroimaging, histologic, and molecular features that may point toward a specific diagnosis. Work of the U.S. Government published under an exclusive license with the RSNA.

Prevalence and MRI findings of incidentally detected pituitary non-enhancing lesion on brain MRI in children

OBJECTIVES

To determine the prevalence and MRI findings of incidentally detected pituitary nonenhancing lesion on brain MRI in children, and to compare the detection rates of pituitary nonenhancing lesion according to magnetic field strength and acquisition technique.

METHODS

Pediatric patients (≤18 years old) who underwent brain MRI with contrast-enhancement between January 2018 and September 2019 were retrospectively included (n=365). The presence, size, and signal intensity of pituitary nonenhancing lesions were assessed by two radiologists. The prevalence of pituitary nonenhancing lesions was compared between different magnetic field strengths and MRI acquisition techniques.

RESULTS

Pituitary nonenhancing lesions were identified in 76 patients (20.8%). The anteroposterior diameter of pituitary nonenhancing lesion was the smallest diameter in most patients (93.4%; mean diameter ± SD of 2.4 ± 1.5 mm; range: 0.9-9.0 mm). Sixty-seven percent of the pituitary nonenhancing lesions were hypointense on T1-weighted imaging, 44.1% were hyperintense on T2-weighted imaging, and 12.9% showed low signal intensity on susceptibility-weighted imaging. There was no diffusion restriction in any of the nonenhancing lesions. There was no significant difference in the prevalence of pituitary nonenhancing lesions according to magnetic field strength, age, gender, slice thickness, or 2D vs. 3D contrast-enhanced T1-weighted imaging sequence.

CONCLUSIONS

Pituitary nonenhancing lesions were identified on contrast-enhanced brain MRI in 20.8% of pediatric patients, with no significant difference in the prevalence according to magnetic field strength, slice thickness, and 2D or 3D contrast-enhanced T1-weighted imaging.

Incidental Pituitary Cysts in Children: Does Growth Hormone Treatment Affect Cyst Size?

OBJECTIVE

To evaluate the response of incidentally discovered pituitary cysts to growth hormone (GH) treatment.

METHODS

A retrospective chart review was performed of children with pituitary cysts on magnetic resonance imaging (MRI) over a 5-year period. Records and images were reviewed, and the results were analyzed using descriptive statistics. Children with pituitary cysts who received GH treatment were compared with those without.

RESULTS

We identified 109 children with pituitary cysts, 24 were treated with GH therapy. The average age was 8.5 ± 5.1 years. Children whose initial MRI scan was to evaluate growth hormone deficiency were more commonly male and non-Hispanic White compared with those with scans for other indications (male, 18 of 24 vs 35 of 85, P = .003; White, 23 of 24 vs 58 of 85, P = .004). Among patients who received GH treatment, 12 had follow-up MRI. Six had no change in cyst size and 6 had a decrease in cyst size. We observed no difference in the likelihood of cyst growth between those who received GH and those who did not (0 of 12 cysts with GH vs 1 of 15 cysts without GH showed growth at follow-up). No patient had neurologic deficits attributable to the pituitary cyst at any time.

CONCLUSION

In a single-institution, retrospective study, we find no evidence of growth in pituitary cysts in response to GH therapy.

Dealing With Brain MRI Findings in Pediatric Patients With Endocrinological Conditions: Less Is More?

Neuroimaging is a key tool in the diagnostic process of various clinical conditions, especially in pediatric endocrinology. Thanks to continuous and remarkable technological developments, magnetic resonance imaging can precisely characterize numerous structural brain anomalies, including the pituitary gland and hypothalamus. Sometimes the use of radiological exams might become excessive and even disproportionate to the patients' medical needs, especially regarding the incidental findings, the so-called "incidentalomas". This unclarity is due to the absence of well-defined pediatric guidelines for managing and following these radiological findings. We review and summarize some indications on how to, and even if to, monitor these anomalies over time to avoid unnecessary, expensive, and time-consuming investigations and to encourage a more appropriate follow-up of brain MRI anomalies in the pediatric population with endocrinological conditions.