Prevalence and Reporting Rates of Incidental Dental Disease on Head CT Examinations.

RATIONALE AND OBJECTIVES: Routine head computed tomography (CT) examinations often inadvertently include dental pathology which is often overlooked. The purpose of this study is to examine the prevalence of dental disease incidentally present and detected on head CT examinations, and to determine the effect of the institution of a dental disease field or macro in a standardized head CT dictation template on the rate of reporting dental disease. MATERIALS AND METHODS: Head CT examinations were retrospectively and randomly selected from all examinations performed 6 months before, and 6 months after the institution of a dental disease field in a standardized head CT template. Dental findings were recorded from the initial finalized report. Examination images were subsequently reviewed for the presence of dental disease by two neuroradiologists who were blinded to the original reports and to each other's findings. RESULTS: One hundred examinations were reviewed in the analysis. At our institution, 33% of the randomly selected head CT examinations included the level of the teeth (100/307). Dental disease was determined to be present in 40%-41% of these cases. Only 11% of the initial reports mentioned dental disease (P < .01). Addition of a dental disease field in the dictation template resulted in no significant difference in reporting dental disease (14% vs 8%, P = .371). CONCLUSIONS: Incidental dental disease is common and frequently underreported. Inclusion of a dental disease field in a standardized template does not significantly improve the rate of reporting dental disease.

A Retrospective Analysis of the Efficacy of Pembrolizumab in Melanoma Patients With Brain Metastasis.

A total of 50% of patients with melanoma will develop brain metastasis (BM). Pembrolizumab was approved for treatment of metastatic melanoma on the basis of significant systemic antitumor activity. Because of low enrollment of patients with BM in pembrolizumab trials, efficacy against melanoma BM remains unknown. We reviewed records of 89 consecutive patients with melanoma treated with pembrolizumab at our institution between May 1, 2014 and October 31, 2015 to determine the time to progression. Thirty-six (40%) patients had BM before pembrolizumab. Twenty-six (72%) patients with BM had received prior treatment for BM. With median follow-up of 17.2 months, 54 patients (61%) developed progressive disease on pembrolizumab. Intracranial progression occurred in 19 patients (21%), 3 of whom did not have BM before treatment. Median time to progression at any site was 6 months for those without BM (n=53), 5 months for those with treated BM (n=26), and 1.2 months for patients with untreated BM (n=10). Using a Cox regression model adjusted for baseline factors, there was a statistically significant (Wald χ P=0.003) reduction in the hazard of progression for patients without BM [hazard ratio, 0.19; 90% confidence interval, 0.08-0.42) and patients with treated BM (hazard ratio, 0.27; 90% confidence interval, 0.12-0.64) compared with those with untreated BM. In conclusion, melanoma patients with pretreated BM can have durable systemic responses to pembrolizumab. Large, prospective studies are needed to evaluate the intracranial antitumor activity of pembrolizumab in melanoma patients with untreated BM.

Spinal Intradural, Extramedullary Ependymoma with Astrocytoma Component: A Case Report and Review of the Literature.

Ependymomas are common spinal lesions, with the vast majority arising in an intramedullary location. Several cases have been described in the literature of ependymomas in an intradural, extramedullary location. The authors present a case of a 56-year-old female who presented with several weeks of lower back pain and weakness. MRI revealed an intradural, extramedullary enhancing mass at L1-L2. The mass was successfully resected surgically. Pathologic evaluation revealed a low grade glioma with components of both ependymoma and pilocytic astrocytoma with MUTYH G382D mutation. Extramedullary ependymomas are very rare tumors. To the authors' knowledge, this is the first case of ependymoma/astrocytoma collision tumors described in an extramedullary location.

What is the diagnostic value of head MRI after negative head CT in ED patients presenting with symptoms atypical of stroke?

The diagnostic value of head magnetic resonance imaging after negative head computed tomography for emergency department patients with vague neurologic symptoms, such as dizziness and altered mental status, remains an ongoing discussion. The objective of this study is to detect the subgroup of patients with such presentations having minor strokes whom may benefit from primary and secondary stroke prevention. We conducted a retrospective analysis and stratified patient risk factors associated with positive findings on subsequent head MRI ordered by the emergency department physician following a normal head CT. Two hundred fifty-two patients presenting with atypical stroke symptoms to the emergency department had a negative head CT followed by head MRI within 24 h ordered by emergency department clinician (123 males and 129 females; mean age of 59.4). Twenty nine of the 252 patients (11.5 %) had findings of acute to subacute infarct on the subsequent MRI. Positive MRI findings were statistically correlated with the following variables: age (p < 0.001), history of hyperlipidemia (p = 0.019), hypertension (p < 0.001), diabetes (p = 0.004), anticoagulation use (p = 0.029), and prior transient ischemic attack or stroke (p < 0.001). The mean age of the MRI-positive group was 74.1 years, with a mean difference of 16.7 ± 2.4 years more than the MRI-negative group (95 % CI, 11.8-21.5 years) (t = 6.8, p < 0.001). Emergency physicians caring for patients with vague neurologic complaints should maintain a lower threshold for ordering a head MRI despite a negative head CT for elderly patients with a history of prior stroke or transient ischemic attack to exclude a CT occult or minor ischemic stroke.

Spectrum of Extramammary Malignant Neoplasms in the Breast With Radiologic-Pathologic Correlation.

Although primary breast cancer is the most common malignancy identified by breast imaging, extramammary malignancies may also rarely be encountered. These uncommon lesions may reflect primary neoplasms of nonmammary origin as well as secondary metastatic lesions, and include lymphoma, melanoma, neuroendocrine tumors, gastrointestinal tract malignancies, and angiosarcoma among other entities. Malignant extramammary breast lesions may be encountered during routine mammographic screening, identified during the diagnostic evaluation of a palpable breast abnormality, or may be detected incidentally during imaging of other organs of interest. As such, the radiologist should have familiarity with the appearance of these lesions. This article focuses on a review of several of the most common extramammary metastases to the breast, as well as a few lesions that may develop as either primary or secondary lesions.

NUT midline carcinoma: a case report with a novel translocation and review of the literature.

NUT midline carcinoma (NMC) is a rare, genetically defined, highly lethal undifferentiated carcinoma occurring in the midline location of the neck, head or mediastinum. We present the case of a 23 year-old otherwise healthy Chinese male immigrant who presented with complaints of sore throat and right sided neck mass. The initial treatment was for likely EBV infection with streptococcal superinfection. Although continued investigation was pursued shortly after initial presentation, the mass had enlarged and become necrotic with significant nodal involvement. The mass was diagnosed as an NMC tumor with a novel three-way translocation t(9;15;19; q34;q13;p13.1). Despite aggressive treatment, the patient's condition progressed rapidly and he died within 3 months of initial diagnosis. Standard therapeutic interventions have been ineffective in the treatment of NMC. Earlier diagnosis could allow characterization of the natural progression of this entity, and allow more time for intervention or development of novel therapies, potentially related to molecular targets. This continues to require a high index of suspicion and early imaging with cytogenetic and immunohistochemical confirmation.

Effect of antiplatelet therapy on thromboembolism after flow diversion with the pipeline embolization device.

OBJECT: Flow-diverting stents offer a novel treatment approach to intracranial aneurysms. Data regarding the incidence of acute procedure-related thromboembolic complications following deployment of the Pipeline Embolization Device (PED) remain scant. The authors sought to determine the rate of embolic events in a bid to identify potential risk factors and assess the role of platelet inhibition. METHODS: Data in all patients receiving a PED for treatment of an intracranial aneurysm were prospectively maintained in a database. Diffusion-weighted 3-T MRI was performed within 24 hours of PED deployment. The incident rate of procedural embolism was established, and univariate analysis was then performed to determine any associations of embolic events with measured variables. The degree of platelet inhibition in response to aspirin and clopidogrel was evaluated by challenging the platelet samples with arachidonic acid and adenosine diphosphate, respectively, and then performing formal light transmission platelet aggregometry. RESULTS: Twenty-three patients with 26 aneurysms were eligible for inclusion in the study. Thirty-one PEDs were deployed in 25 procedures. All ischemic lesions detected on diffusion-weighted 3-T MRI were identified as embolic based on their location and distribution, with none appearing to be due to perforator artery occlusion. Procedural embolic events were found in the target parent vessel territory in 13 (52%) of 25 procedures, with no patients harboring lesions contralateral to the deployed PED. The number of embolic events per procedure ranged from 3 to 16, with a mean of 5.4. There was no significant difference between cases with and without procedural embolism in platelet inhibition by aspirin (mean 15% vs 12% residual activation; p = 0.28), platelet inhibition by clopidogrel (mean 41% vs 41% residual activation; p = 0.98), or intraprocedural heparin-induced anticoagulation (mean activated clotting time 235 seconds vs 237 seconds; p = 0.81). By multivariate analysis, the authors identified larger aneurysm size (p = 0.03) as the single variable significantly associated with procedural embolism. There was no significant relationship between aneurysm size and the number of embolic events (p = 0.32) or the total burden of the embolism lesion area (p = 0.53). CONCLUSIONS: Acute embolism following use of the PED for treatment of intracranial aneurysms is more common than hypothesized. The only identifiable risk factor for embolism appears to be greater aneurysm size, perhaps indicating significant disturbed flow across the aneurysm neck with ingress and egress through the PED struts. The strength of antiplatelet therapy, as measured by residual platelet aggregation, did not appear to be associated with cases of procedural embolism. Further work is needed to determine the implications of these findings and whether anticoagulation regimens can be altered to lower the rate of complications following PED deployment.

Detection of meningioma metastasis to liver and lung using somatostatin receptor scintigraphy.

Extracranial meningioma metastasis is rare. We report a case of a 74-year-old Caucasian man with intracranial recurrence of atypical meningioma treated with a combination of surgical resection and gamma knife radiotherapy over a 4-year period. Somatostatin receptor scintigraphy using (111)In pentreotide for surveillance of tumor recurrence showed multiple pulmonary and hepatic metastases.

Incomplete stent apposition in Enterprise stent-mediated coiling of aneurysms: persistence over time and risk of delayed ischemic events.

OBJECT: Incomplete stent apposition of the closed cell-design Enterprise stent following stent-mediated coil embolization of intracranial aneurysms has been associated with increased risk of periprocedural thromboembolic events. In this study, the authors seek to determine the natural history of incomplete stent apposition and evaluate the clinical implications of the phenomenon. METHODS: Since January 2009, all patients receiving Enterprise stents in the treatment of intracranial aneurysms at the authors' institution have undergone serial 3-T MRI with incomplete stent apposition identified by the crescent sign on multiplanar reconstructions of MR angiograms. Magnetic resonance images and MR angiograms obtained at 3, 9, and 18 months after stent-assisted coil embolization were analyzed along with admission and follow-up clinical medical records. These records were evaluated for any radiographic and clinical, transient or permanent ischemic neurological events. RESULTS: Fifty patients receiving Enterprise stents were eligible for inclusion and analysis in the study. Incomplete stent apposition was identified in postoperative imaging studies in 22 (44%) of 50 patients, with 19 (86%) of 22 crescent signs persisting and 3 (14%) of 22 crescent signs resolving on subsequent serial imaging. Delayed ischemic events occurred in 8 (16%) of 50 cases, and all cases involved patients with incomplete stent apposition. The events were transient ischemic attacks (TIAs) in 5 cases, asymptomatic radiographic strokes in 2 cases, and symptomatic strokes and TIAs in the final case. There were no delayed ischemic events in patients who did not have incomplete stent apposition. Only 1 of the delayed ischemic events (2%) was permanent and symptomatic. The postoperative presence of a crescent sign and persistence of the crescent sign were both significantly associated with delayed ischemic events (p < 0.001 and p = 0.002, respectively). CONCLUSIONS: Incomplete stent apposition is a temporally persistent phenomenon, which resolves spontaneously in only a small minority of cases and appears to be a risk factor for delayed ischemic events. Although further follow-up is needed, these results suggest that longer duration of antiplatelet therapy and clinical follow-up may be warranted in cases of recognized incomplete stent apposition.

Pulmonary interstitial glycogenosis.

Although bronchopulmonary dysplasia (BPD) is a common cause of interstitial lung disease in chronically intubated premature neonates, other interstitial lung disease in nonintubated infants is rare. We present a case of pulmonary interstitial glycogenosis that developed in a nonintubated, 31-week gestation infant in whom infectious etiologies had been excluded. The infant was well initially and then developed respiratory distress at 18 days of life. Radiographs at first day of life were normal, but CT and radiographic findings at 18 days of life showed severe interstitial lung disease, mimicking BPD. Lung biopsy showed pulmonary interstitial glycogenosis. This entity is not well described in the pediatric radiology literature and is important to consider, as the condition is responsive to a course of corticosteroids.