Spontaneous intracranial hypotension: Exploring the viability of non-contrast FLAIR as a substitute for contrast-enhanced T1WI in assessing pachymeningeal thickening.

PURPOSE: To avoid contrast administration in spontaneous intracranial hypotension (SIH), some studies suggest accepting diffuse pachymeningeal hyperintensity (DPMH) on non-contrast fluid-attenuated inversion recovery (FLAIR) as an equivalent sign to diffuse pachymeningeal enhancement (DPME) on contrast-enhanced T1WI (T1ce), despite lacking thorough performance metrics. This study aimed to comprehensively explore its feasibility. METHODS: In this single-center retrospective study, between April 2021 and November 2023, brain MRI examinations of 43 patients clinically diagnosed with SIH were assessed using 1.5 and 3.0 Tesla MRI scanners. Two radiologists independently assessed the presence or absence of DPMH on FLAIR and DPME on T1ce, with T1ce serving as a gold-standard for pachymeningeal thickening. The contribution of the subdural fluid collections to DPMH was investigated with quantitative measurements. Using Cohen's kappa statistics, interobserver agreement was assessed. RESULTS: In 39 out of 43 patients (90.7%), pachymeningeal thickening was observed on T1ce. FLAIR sequence produced an accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 72.1%, 71.8%, 75.0%, 96.6%, and 21.4% respectively, for determining pachymeningeal thickening. FLAIR identified pachymeningeal thickening in 28 cases; however, among these, 21 cases (75%) revealed that the pachymeningeal hyperintense signal was influenced by subdural fluid collections. False-negative rate for FLAIR was 28.2% (11/39). CONCLUSION: The lack of complete correlation between FLAIR and T1ce in identifying pachymeningeal thickening highlights the need for caution in removing contrast agent administration from the MRI protocol of SIH patients, as it reveals a major criterion (i.e., pachymeningeal enhancement) of Bern score.

Clinical and Immunologic Features of a Patient With Homozygous FNIP1 Variant.

Agammaglobulinemia represents the most profound primary antibody deficiency, stemming from early cessation of B-cell development. Deficiency in folliculin-interacting protein 1 (FNIP1) is a novel inborn error of immunity characterized by a severe defect in B-cell development, agammaglobulinemia, variable neutropenia, and hypertrophic cardiomyopathy. FNIP1 plays a critical role in B-cell development and metabolic homeostasis, establishing a metabolic checkpoint that ensures pre-B cells possess sufficient metabolic capacity to undergo division while concurrently limiting lymphogenesis due to abnormal growth. Disruption of FNIP1 functionality affects the fundamental metabolic regulators adenosine monophosphate-activated protein kinase and mTOR, culminating in a severe B-cell deficiency alongside hypogammaglobulinemia, hypertrophic cardiomyopathy, preexcitation syndrome, and intermittent neutropenia. This case report presents an 11-month-old male patient with FNIP1 deficiency who, in addition to classical features, exhibited posterior cerebellar hypoplasia.

Utility of diffusion tensor imaging and generalized q-sampling imaging for predicting short-term clinical effect of deep brain stimulation in Parkinson's disease.

PURPOSE: To assess whether diffusion tensor imaging (DTI) and generalized q-sampling imaging (GQI) metrics could preoperatively predict the clinical outcome of deep brain stimulation (DBS) in patients with Parkinson's disease (PD). METHODS: In this single-center retrospective study, from September 2021 to March 2023, preoperative DTI and GQI examinations of 44 patients who underwent DBS surgery, were analyzed. To evaluate motor functions, the Unified Parkinson's Disease Rating Scale (UPDRS) during on- and off-medication and Parkinson's Disease Questionnaire-39 (PDQ-39) scales were used before and three months after DBS surgery. The study population was divided into two groups according to the improvement rate of scales: ≥ 50% and < 50%. Five target regions, reported to be affected in PD, were investigated. The parameters having statistically significant difference were subjected to a receiver operating characteristic (ROC) analysis. RESULTS: Quantitative anisotropy (qa) values from globus pallidus externus, globus pallidus internus (qa_Gpi), and substantia nigra exhibited significant distributional difference between groups in terms of the improvement rate of UPDRS-3 scale during on-medication (p = 0.003, p = 0.0003, and p = 0.0008, respectively). In ROC analysis, the best parameter in predicting DBS response included qa_Gpi with a cut-off value of 0.01370 achieved an area under the ROC curve, accuracy, sensitivity, and specificity of 0.810, 73%, 62.5%, and 85%, respectively. Optimal cut-off values of ≥ 0.01864 and ≤ 0.01162 yielded a sensitivity and specificity of 100%, respectively. CONCLUSION: The imaging parameters acquired from GQI, particularly qa_Gpi, may have the ability to non-invasively predict the clinical outcome of DBS surgery.

Clinicopathological Correlates of PIT1 and SF1-Multilineage Pituitary Neuroendocrine Tumors and the Diagnostic Utility of NKX2.2 Immunohistochemistry in Pituitary Pathology.

CONTEXT.­: PIT1 and SF1-multilineage pituitary neuroendocrine tumors (PitNETs) have been defined since the classification of adenohypophysial tumors based on the PIT1, SF1, and TPIT transcription factors. OBJECTIVE.­: To describe the clinicopathologic features of PIT1 and SF1-multilineage PitNETs and to contribute to the pituitary pathology practice by questioning the expression of NKX2.2 in PitNETs. DESIGN.­: We reviewed 345 PitNETs and described the clinicopathologic features of 8 PIT1 and SF1-multilineage tumors. NKX2.2 positivity and staining pattern were compared to those of 45 PitNETs from the control group. RESULTS.­: PIT1 and SF1-multilineage PitNET patients had a mean age of 41.13 (range, 14-58 years) and a mean diameter of 14.0 mm (range, 8-20 mm). The most common clinical presentation was acromegaly (6 of 8), and postoperative remission was achieved in all patients. On histomorphologic examination, a pseudopapillary pattern was seen in 5 of the tumors, either focally or diffusely. In addition to PIT1 and SF1, there was a diffuse staining with growth hormone and a predominantly perinuclear staining with cytokeratin 18. With NKX2.2, all multilineage tumors were positive, of which 5 were diffuse and 3 were focal. In the control group, 8 tumors (8 of 45) were positive, of which only 1 was diffuse and 7 were focal. CONCLUSIONS.­: In conclusion, NKX2.2 is a transcription factor that can be used as an additional tool in pituitary pathology, and PIT1 and SF1-multilineage PitNETs are specific tumors that usually present with acromegaly, show signs of a nonaggressive clinical course, have a pseudopapillary histomorphology, and express NKX2.2.

Distinguishing Pituitary Metastasis and Pituitary Neuroendocrine Tumors through Conventional MR Imaging and Clinical Features.

BACKGROUND AND PURPOSE: Given their overlapping features, pituitary metastases frequently imitate pituitary neuroendocrine tumors in neuroimaging studies. This study aimed to distinguish pituitary metastases from pituitary neuroendocrine tumors on the basis of conventional MR imaging and clinical features as a practical approach. MATERIALS AND METHODS: In this 2-center retrospective study, backward from January 2024, preoperative pituitary MR imaging examinations of 22 pituitary metastases and 74 pituitary neuroendocrine tumors were analyzed. Exclusion criteria were as follows: absence of a definitive histopathologic diagnosis, history of pituitary surgery or radiation therapy before MR imaging, and pituitary neuroendocrine tumors treated with medical therapy. Two radiologists systematically evaluated 13 conventional MR imaging features that have been reported more commonly as indicative of pituitary metastases and pituitary neuroendocrine tumors in the literature. Age, sex, history of cancer, and maximum tumor size constituted the clinical/epidemiologic features. The primary cancer origin for this study was also noted. Univariable and multivariable logistic regression was used for the selection of variables, determining independent predictors, and modeling. Interobserver agreement was evaluated for all imaging parameters using the Cohen κ statistic or intraclass correlation coefficient. RESULTS: A total of 22 patients with pituitary metastases (8 women; mean age, 49.5 [SD, 13] years) and 74 patients with pituitary neuroendocrine tumors (36 women; mean age, 50.1 [SD, 11] years) were enrolled. There was no statistically significant distributional difference in age, sex, or maximum tumor size between the 2 groups. Lung cancer (9/22; 41%) was the most commonly reported primary tumor, followed by breast (3/22; 13.6%) and unknown cancer (3/22; 13.6%). Logistic regression revealed 3 independent predictors: rapid growth on control MR imaging, masslike or nodular expansion of the pituitary stalk, and a history of cancer. The model based on these 3 features achieved an area under the curve, accuracy, sensitivity, specificity, and Brier score of 0.987 (95% CI, 0.964-1), 97.9% (95% CI, 92.7%-99.8%), 95.5% (95% CI, 77.2%-99.9%), 98.6% (95% CI, 92.7%-100%), and 0.025, respectively. CONCLUSIONS: Two conventional features based on pituitary MR imaging with the clinical variable of history of cancer had satisfying predictive performance, making them potential discriminators between pituitary metastases and pituitary neuroendocrine tumors. In cases in which differentiation between pituitary metastases and pituitary neuroendocrine tumors poses a challenge, the results of this study may help with the diagnosis.

Diagnostic Performance of Contrast-enhanced Mammography: Comparison With MRI and Mammography.

OBJECTIVE: To compare the diagnostic performance of contrast-enhanced mammography (CEM) with MRI and mammography (MG) based on histopathological results. METHODS: In this IRB-approved study, written informed consent was obtained from all patients. Images from 40 patients (62 lesions) with suspicious findings on US between March 2018 and August 2018 were evaluated. Sensitivity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of CEM, MRI, and MG were evaluated and compared within a 95% confidence interval. Maximum dimensions of lesions were measured and correlations of results were evaluated with Spearman's Rho test. RESULTS: In the histopathological analysis, 66% (41/62) of lesions were malignant and 34% (21/62) of lesions were benign. Contrast-enhanced mammography, MRI, and MG had sensitivities of 100% (41/41), 100% (41/41), and 80% (33/41), respectively. The sensitivity of CEM and MRI was significantly better than that of MG (P = 0.03). The NPVs of CEM (100%, 7/7) and MRI (100%, 14/14) were statistically higher than the NPV of MG (60%, 12/20) (P = 0.03). The false-positive rates for CEM, MRI, and MG were 33% (7/21), 66% (14/21), and 42% (9/21), respectively. Contrast-enhanced mammography had a significantly lower false-positive rate than MRI (P < 0.001). Mammography had the highest false-negative rate, missing 19% (8/41) of malignant lesions. CONCLUSION: Contrast-enhanced mammography has similar performance characteristics to MRI and improved performance characteristics relative to MG. In particular, CEM and MRI have similar sensitivity and NPVs and both are superior in each of these metrics to MG.