A multi-institutional meningioma MRI dataset for automated multi-sequence image segmentation.

Meningiomas are the most common primary intracranial tumors and can be associated with significant morbidity and mortality. Radiologists, neurosurgeons, neuro-oncologists, and radiation oncologists rely on brain MRI for diagnosis, treatment planning, and longitudinal treatment monitoring. However, automated, objective, and quantitative tools for non-invasive assessment of meningiomas on multi-sequence MR images are not available. Here we present the BraTS Pre-operative Meningioma Dataset, as the largest multi-institutional expert annotated multilabel meningioma multi-sequence MR image dataset to date. This dataset includes 1,141 multi-sequence MR images from six sites, each with four structural MRI sequences (T2-, T2/FLAIR-, pre-contrast T1-, and post-contrast T1-weighted) accompanied by expert manually refined segmentations of three distinct meningioma sub-compartments: enhancing tumor, non-enhancing tumor, and surrounding non-enhancing T2/FLAIR hyperintensity. Basic demographic data are provided including age at time of initial imaging, sex, and CNS WHO grade. The goal of releasing this dataset is to facilitate the development of automated computational methods for meningioma segmentation and expedite their incorporation into clinical practice, ultimately targeting improvement in the care of meningioma patients.

Spontaneous Hemorrhage Followed by Paraparesis in a Patient with a Spinal Meningioma.

BACKGROUND: Although rare, spinal meningiomas may cause motor and sensory deficits or difficulty with bladder or bowel function due to spinal cord compression. Although hemorrhage of intracranial meningiomas is well documented, there are very few cases of hemorrhage or hematoma associated with spinal meningiomas in the literature. Spinal meningiomas have been reported to be associated with subdural, epidural, intratumoral, and subarachnoid hemorrhage, and usually in the setting of an inciting event such as lumbar puncture or anticoagulation therapy. CASE DESCRIPTION: A 68-year-old women presented to the emergency room with acute onset of paraparesis in the lower extremities. Magnetic resonance imaging findings were inconclusive for cause but showed spinal cord compression. Intraoperative findings demonstrated an intratumoral hemorrhage and pathology was consistent with meningioma. CONCLUSIONS: To the best of our knowledge, this is the first report in English literature of a patient who first develops symptoms from a spinal meningioma with spontaneous intratumoral hemorrhage presenting with acute paraparesis. Magnetic resonance imaging findings in retrospect match surgical intraoperative findings. Prompt surgical intervention can result in complete resolution of neurologic deficits.

Early detection of recurrent disease by FDG-PET/CT leads to management changes in patients with squamous cell cancer of the head and neck.

OBJECTIVE: The objective of this study was to compare the efficacy of surveillance high-resolution computed tomography (HRCT) and physical examination/endoscopy (PE/E) with the efficacy of fluorodeoxyglucose (FDG)-positron emission tomography (PET)/HRCT for the detection of relapse in head and neck squamous cell carcinoma (HNSCC) after primary treatment. METHODS: This is a retrospective analysis of contemporaneously performed FDG-PET/HRCT, neck HRCT, and PE/E in 99 curatively treated patients with HNSCC during post-therapy surveillance to compare performance test characteristics in the detection of early recurrence or second primary cancer. RESULTS: Relapse occurred in 19 of 99 patients (20%) during a median follow-up of 21 months (range: 9-52 months). Median time to first PET/HRCT was 3.5 months. The median time to radiological recurrence was 6 months (range: 2.3-32 months). FDG-PET/HRCT detected more disease recurrences or second primary cancers and did so earlier than HRCT or PE/E. The sensitivity, specificity, and positive and negative predictive values for detecting locoregional and distant recurrence or second primary cancer were 100%, 87.3%, 56.5%, and 100%, respectively, for PET/HRCT versus 61.5%, 94.9%, 66.7%, and 93.8%, respectively, for HRCT versus 23.1%, 98.7%, 75%, and 88.6%, respectively, for PE/E. In 19 patients with true positive PET/HRCT findings, a significant change in the management of disease occurred, prompting either salvage or systemic therapy. Of the 14 curatively treated patients, 11 were alive with without disease at a median follow-up of 31.5 months. CONCLUSION: FDG-PET/HRCT has a high sensitivity in the early detection of relapse or second primary cancer in patients with HNSCC, with significant management implications. Given improvements in therapy and changes in HNSCC biology, appropriate modifications in current post-therapy surveillance may be required to determine effective salvage or definitive therapies.

Radiation exposure from medical imaging in patients with chronic and recurrent conditions.

PURPOSE: Advances in medical imaging have been associated with increased utilization and increased radiation exposure, especially for patients with chronic and recurrent conditions. The authors estimated the cumulative radiation doses from medical imaging for specific cohorts with chronic and recurrent conditions. METHODS: All patients diagnosed with hydrocephalus (n = 1,711), pulmonary thromboembolic disease (n = 3,220), renal colic (n = 5,855), and cardiac disease (n = 11,072) from January 1, 2000, to December 31, 2005, were retrospectively identified. Each imaging examination that used ionizing radiation from 2000 to 2008 was incorporated into an estimate of total effective dose and organ-specific doses. Patients with high levels of radiation exposure after 3 years (total effective dose > 50 mSv; dose to the ocular lens > 150 mSv) were identified. RESULTS: The mean estimated effective doses for the surviving diagnostic cohorts after 3 years were 12.3 mSv for patients with hydrocephalus, 21.7 mSv for those with pulmonary thromboembolic disease, 18.7 mSv for those with renal colic, and 14.0 mSv for those with cardiac disease. Among patients with hydrocephalus, 26.3% (339 of 1,291) had radiation doses > 150 mSv to the ocular lens within 3 years. In all cohorts, the proportion of patients with total effective doses > 50 mSv within 3 years was significantly higher for those diagnosed in 2004 and 2005 than for those diagnosed in 2000 and 2001. CONCLUSION: Patients with hydrocephalus, pulmonary thromboembolic disease, renal colic, and cardiac disease received radiation exposures that may put them at increased risk for cancer. Moreover, the proportion who received estimated total effective doses > 50 mSv within 3 years was significantly higher for those diagnosed most recently. It is the responsibility of institutions and physicians to critically evaluate their infrastructures, diagnostic strategies, and imaging techniques for each individual patient, with an eye toward minimizing cumulative medical radiation exposure.

Success of a safe and simple algorithm to reduce use of CT pulmonary angiography in the emergency department.

OBJECTIVE: The purpose of our study was to determine whether the radiation exposure to patients with suspected pulmonary embolism (PE) could be decreased by safely increasing the use of ventilation-perfusion (V/Q) scanning and decreasing the use of CT pulmonary angiography (CTPA) through an educational intervention. MATERIALS AND METHODS: Collaborative educational seminars were held among the radiology, nuclear medicine, and emergency medicine departments in December 2006 and January 2007 regarding the radiation dose and accuracies of V/Q scanning and CTPA for diagnosing PE. To reduce radiation exposure, an imaging algorithm was introduced in which emergency department patients with a clinical suspicion of PE underwent chest radiography. If the chest radiograph was normal, V/Q scanning was recommended, otherwise CTPA was recommended. We retrospectively tallied the number and results of CTPA and V/Q scanning and calculated mean radiation effective dose before and after the intervention. False-negative findings were defined as subsequent thromboembolism within 90 days. RESULTS: The number of CTPA examinations performed decreased from 1,234 in 2006 to 920 in 2007, and the number of V/Q scans increased from 745 in 2006 to 1,216 in 2007. The mean effective dose was reduced by 20%, from 8.0 mSv in 2006 to 6.4 mSv in 2007 (p < 0.0001). The patients who underwent CTPA and V/Q scanning in 2006 were of similar age. In 2007, the patients who underwent V/Q scanning were significantly younger. There was no significant difference in the false-negative rate (range, 0.8-1.2%) between CTPA and V/Q scanning in 2006 and 2007. CONCLUSION: The practice patterns of physicians changed in response to an educational intervention, resulting in a reduction in radiation exposure to emergency department patients with suspected PE without compromising patient safety.

Percutaneous gastrostomy of the excluded gastric segment after Roux-en-Y gastric bypass surgery.

A new technique for percutaneous gastrostomy of a decompressed excluded gastric segment after Roux-en-Y gastric bypass (RYGBP) surgery is described and the results in a single institution are reviewed. Computed tomography guidance was used to place a 21- or 22-gauge needle into the lumen of the stomach and distend it to allow placement of a feeding catheter. Ten women underwent the procedure, and despite only three patients having clear access windows, gastrostomy placement was ultimately successful in all 10 patients. Percutaneous gastrostomy of the decompressed excluded gastric segment after RYGBP surgery can be challenging, but a high rate of success can be achieved.

Structural basis for dimerization of the Grb10 Src homology 2 domain. Implications for ligand specificity.

Grb7, Grb10, and Grb14 are members of a distinct family of adapter proteins that interact with various receptor tyrosine kinases upon receptor activation. Proteins in this family contain several modular signaling domains including a pleckstrin homology (PH) domain, a BPS (between PH and SH2) domain, and a C-terminal Src homology 2 (SH2) domain. Although SH2 domains are typically monomeric, we show that the Grb10 SH2 domain and also full-length Grb10 gamma are dimeric in solution under physiologic conditions. The crystal structure of the Grb10 SH2 domain at 1.65-A resolution reveals a non-covalent dimer whose interface comprises residues within and flanking the C-terminal alpha helix, which are conserved in the Grb7/Grb10/Grb14 family but not in other SH2 domains. Val-522 in the BG loop (BG3) and Asp-500 in the EF loop (EF1) are positioned to interfere with the binding of the P+3 residue of a phosphopeptide ligand. These structural features of the Grb10 SH2 domain will favor binding of dimeric, turn-containing phosphotyrosine sequences, such as the phosphorylated activation loops in the two beta subunits of the insulin and insulin-like growth factor-1 receptors. Moreover, the structure suggests the mechanism by which the Grb7 SH2 domain binds selectively to pTyr-1139 (pYVNQ) in Her2, which along with Grb7 is co-amplified in human breast cancers.