4D CT Parathyroid for the General Radiologist: A Pictorial Essay of Illustrative Cases.

Primary hyperparathyroidism is a morbid disease that affects multiple organ systems and causes a multitude of debilitating symptoms if not properly diagnosed and treated. Minimally invasive parathyroidectomy is now the standard of care for the treatment of primary hyperparathyroidism. In the hands of experienced high-volume surgeons, the success rate of this treatment is approximately 95%. Preoperative planning with 4-dimensional computed tomography (4DCT) is becoming increasingly common as a first line imaging modality. It is important for general radiologists to become familiar with this type of study in order to better assist their surgical colleagues. This image-rich review will discuss hyperparathyroidism, benefits, and weaknesses of different imaging modalities, 4DCT imaging protocol, relevant anatomy, expected appearance, and location of parathyroid adenomas, ectopic and atypical appearances, multigland disease and important mimics.

Isolated Saccular Hydrops on High-resolution MRI Is Associated With Full Spectrum Menière's Disease.

OBJECTIVE: To describe the clinical presentation of patients with isolated saccular endolymphathic hydrops (EH) detected. STUDY DESIGN: Clinical case series. SETTING: University-based tertiary referral center. PATIENTS: All subjects presenting with vertigo or hearing loss who had isolated saccular EH detected. INTERVENTION: High-resolution delayed-contrast magnetic resonance imaging (MRI) conducted between November 2015 and November 2016. MAIN OUTCOME MEASURES: Audiovestibular testing results and analysis of clinical histories. RESULTS: Isolated saccular EH was detected in 18 subjects. Sixteen met criteria for definite Menière's disease (MD, n = 12) or delayed endolymphatic hydrops (DEH, n = 4). One had a history of sudden sensorineural hearing loss (SSNHL) and 3 years after MRI developed recurrent vertigo characteristic of DEH. One patient had a history of atypical DEH (Tumarkin falls without vertigo following SSNHL). Four patients had Tumarkin falls. Most (83%) demonstrated mild-to-severe low-frequency fluctuating loss, and six (33.3%) had a history of ipsilateral sudden profound SNHL. Nine of the 17 (53%) patients tested had an ipsilateral caloric paresis ranging from 26 to 67%. Ipsilateral vestibular-evoked myogenic potentials showed reduced or absent responses in 5 of the 17 tested (29%). CONCLUSIONS: The full spectrum of MD may be associated with saccular hydrops. We propose that MD and DEH often begin in the saccule, and MRI may provide clues to the pathophysiology of MD. Saccular hydrops was present in one patient with SSNHL who did not develop vertigo spells until 3 years after MRI, indicating that saccular hydrops may be the first manifestation of MD or DEH.

Association Between Neonatal Neuroimaging and Clinical Outcomes in Zika-Exposed Infants From Rio de Janeiro, Brazil.

Importance: Congenital Zika virus (ZIKV) infection may present with a spectrum of clinical and neuroradiographic findings. Objective: To determine whether neuroimaging findings for infants with a history of ZIKV exposure are associated with infant clinical outcomes and gestational age at antenatal ZIKV infection. Design, Setting, and Participants: This cohort study retrospectively reviewed neuroimaging results (computed tomography and/or magnetic resonance imaging scans) of 110 ZIKV-exposed infants from a maternity and children's hospital in Rio de Janeiro, Brazil, following the 2015 to 2016 ZIKV epidemic. Neuroimaging from March 1, 2016, to June 30, 2017, was evaluated to determine whether findings were associated with clinical outcomes and the timing of maternal ZIKV infection. Data were analyzed from July 1, 2017, to August 30, 2018. Exposures: Neuroimaging (computed tomography and/or magnetic resonance imaging) was performed on ZIKV-exposed infants after birth. Blood and/or urine specimens from mothers and infants were tested for ZIKV by polymerase chain reaction assay. Main Outcomes and Measures: Neuroimaging studies were evaluated for structural abnormalities and other forms of brain injury. Results: A total of 110 infants with a mean (SD) gestational age of 38.4 (2.1) weeks had neuroimaging and clinical outcome data reviewed. Of these, 71 (65%) had abnormal neuroimaging findings, with the majority (96%) classified as having severe ZIKV infection at birth. The most common neuroimaging abnormalities were structural abnormalities including brain calcifications, especially at the cortico-subcortical white matter junction, cortex malformations, ventriculomegaly, and reduced brain volumes, followed by brainstem hypoplasia, cerebellar hypoplasia, and corpus callosum abnormalities. Frequency of abnormal imaging was higher in infants with specific clinical findings as opposed to those without them; these findings included fetal brain disruption sequence (100% vs 35%), microcephaly (100% vs 30%), congenital contractures (100% vs 58%), ophthalmologic abnormalities (95% vs 44%), hearing abnormalities (100% vs 58%), and neurologic symptoms (94% vs 10%). Four of 39 infants (10%) without initial evidence of severe ZIKV infection and normal findings on neurologic evaluation at birth had abnormal neuroimaging findings. Neuroimaging abnormalities differed by trimester of maternal ZIKV infection, with 63% of infants born to mothers infected in the first trimester, 13% of infants born to mothers infected in the second trimester, and 1% of infants born to mothers infected in the third trimester exhibiting neuroimaging abnormalities. The odds of abnormal neuroimaging were 7.9 times greater for infants with first trimester ZIKV exposure compared with other trimesters combined (odds ratio, 7.9; 95% CI, 3.0-20.4; P < .001). Conclusions and Relevance: Neuroimaging abnormalities of computed tomography and/or magnetic resonance imaging scans were common in ZIKV-exposed infants. While neuroimaging abnormalities were seen in 10% of infants without clinically severe ZIKV, most occurred almost exclusively among those with clinically severe ZIKV, especially among those with a history of ZIKV exposure in the first trimester.

Reshaping Radiology Precall Preparation: Integrating a Cloud-Based PACS Viewer Into a Flipped Classroom Model.

Preparing residents for the on-call experience in Radiology is one of the most important aspects of education within a training program. Traditionally, this preparation has occurred via a combination of case conferences and didactic lectures by program faculty, daily teaching at the workstation, and precall assessments. Recently, a blended curricular model referred to as the flipped classroom has generated a lot of attention within the realm of graduate medical education. We applied this technique to resident precall education in the subspecialty of Neuroradiology, and surveyed the participants about their perceptions of the course. The structure, implementation, and web-based platform used to create the flipped classroom experience is described herein.

Sudden hearing loss after cialis (tadalafil) use: A unique case of cochlear hydrops.

We discuss a unique case of sudden sensorineural hearing loss after Cialis (tadalafil) use, a phosphodiesterase 5 (PDE5) inhibitor, and the implication of ipsilateral cochlear hydrops seen on magnetic resonance imaging (MRI). We report a case of a 53-year-old male with unilateral low-frequency sudden sensorineural hearing loss (SSNHL) after ingestion of tadalafil. The SSNHL occurred 1 day after ingestion and was associated with aural fullness and tinnitus. There were no symptoms of vertigo. He received oral prednisone immediately after the onset of hearing loss without improvement. Delayed intravenous contrast-enhanced three-dimensional Fluid-attenuated inversion recovery MRI revealed ipsilateral dilation of the cochlear duct without any hydronic change in the vestibular system. Acetazolamide therapy was initiated, and his symptoms improved. A posttreatment audiogram revealed an increase in threshold of 15 dB. To the best of our knowledge, this is the first case of cochlear hydrops visualized on imaging after a PDE5 inhibitor induced SSNHL. Tadalafil and other PDE5 inhibitors have a known association with SSNHL. Despite several proposed mechanisms, there is inconclusive evidence of a causal relationship. Our presented case suggests that cochlear hydrops may be one possible mechanism of PDE5 inhibitor-associated SSNHL. MRI should be considered in the evaluation of such patients who do not respond to oral steroids as initial treatment. Laryngoscope, 2615-2618, 2018.

High Resolution Three-Dimensional Delayed Contrast MRI Detects Endolymphatic Hydrops in Patients With Vertigo and Vestibular Schwannoma.

OBJECTIVE: Advances in high resolution magnetic resonance imaging (MRI) have enabled the detection of endolymphatic hydrops (EH), a pathological ballooning of the endolymphatic fluid system, known to be associated with Menière's disease. When a patient has a known diagnosis of vestibular schwannoma and develops recurrent episodic vertigo spells, many surgeons recommend surgical intervention, attributing the vestibular symptoms to the vestibular schwannoma. The aim of this study is to evaluate the clinical outcome in patients with vestibular schwannoma and EH, treated medically, for recurrent spells of vertigo. PATIENTS: Two patients with EH and vestibular schwannoma who presented with recurrent spells of vertigo are included. Both had characteristic low frequency hearing loss ipsilateral to the schwannoma. INTERVENTION: MRI sequences with 3T scanner (Skyra, Siemens Healthcare, Erlangen, Germany) using high resolution three-dimensional delayed postcontrast protocol included "cisternographic" T2 and delayed intravenous-enhanced three-dimensional fluid-attenuation inversion recovery (DIVE-3D-FLAIR) sequences, performed with 2350 ms (bright perilymph) and 2050 ms (bright endolymph) inversion times and with subtracted images. MAIN OUTCOME MEASURE: MRI FLAIR evaluation of EH and presence or absence of vestibular symptoms. RESULTS: Both patients had resolution of the disabling vertigo spells with a diuretic, and Patient 1 had unchanged EH, while Patient 2 had partial resolution of the EH and the FLAIR hyperintensity. CONCLUSION: When EH coexists with vestibular schwannoma in a patient presenting with recurrent vertigo spells, medical treatments for EH may alleviate the vestibular symptoms. We recommend that patients with small vestibular schwannomas who present with vertigo spells undergo high resolution MRI to evaluate for EH and undergo a trial of medical treatment with diuretics.

Amyloid-ß-related angiitis: a report of 2 cases with unusual presentations.

Amyloid-ß-related angiitis (ABRA) is a rare complication of cerebral amyloid angiopathy in which amyloid-ß deposition in the leptomeningeal and cortical vessels is associated with vasculitis characterized by transmural lymphohistiocytic, often granulomatous, inflammation. Patients usually present with acute to subacute cognitive dysfunction, headaches, and focal neurologic deficits. We report 2 cases of ABRA with unusual clinical presentations, including one case with fatal cerebral edema leading to herniation and Duret hemorrhages, and another associated with both lobar and deep parenchymal hemorrhages with intraventricular extension as well as hypercoagulability. Both showed extensive vascular amyloid-ß deposition associated with granulomatous angiitis and foreign body-type multinucleated giant cells. One of our cases demonstrates the likely effects of ABRA on impairment of fluid regulation leading to severe cerebral edema, which is an uncommon manifestation of ABRA, and may be a result of impaired blood-brain barrier function or malfunction of the neurovascular unit.

Eagle syndrome presenting with external carotid artery pseudoaneurysm.

Eagle syndrome refers to a clinical syndrome caused by the abnormal elongation of the styloid process with calcification/ossification of the stylohyoid ligament. We present the first reported case of Eagle syndrome resulting in an external carotid artery (ECA) pseudoaneurysm. A patient presented to emergency room with an expanding, painful right-neck mass. CT angiography with three-dimensional volume rendering showed a bilobed 4.0-cm right ECA pseudoaneurysm and bilateral ossification of the stylohyoid ligaments with a sharpened edge of the right styloid process at the level of the carotid artery. Aneurysmectomy was performed, and a common carotid to internal carotid bypass with reversed saphenous vein restored arterial continuity. Local resection of the styloid process with a rotational sternocleidomastoid flap was performed. The pathology report was consistent with a diagnosis of a pseudoaneurysm. A six-month clinical follow-up confirmed the complete resolution of symptoms with no neurological deficits.