PET/MR Imaging in Evaluating Treatment Failure of Head and Neck Malignancies: A Neck Imaging Reporting and Data System-Based Study.

BACKGROUND AND PURPOSE: PET/MR imaging is a relatively new hybrid technology that holds great promise for the evaluation of head and neck cancer. The aim of this study was to assess the performance of simultaneous PET/MR imaging versus MR imaging in the evaluation of posttreatment head and neck malignancies, as determined by its ability to predict locoregional recurrence or progression after imaging. MATERIALS AND METHODS: The electronic medical records of patients who had posttreatment PET/MR imaging studies were reviewed, and after applying the exclusion criteria, we retrospectively included 46 studies. PET/MR imaging studies were independently reviewed by 2 neuroradiologists, who recorded scores based on the Neck Imaging Reporting and Data System (using CT/PET-CT criteria) for the diagnostic MR imaging sequences alone and the combined PET/MR imaging. Treatment failure was determined with either biopsy pathology or initiation of new treatment. Statistical analyses including univariate association, interobserver agreement, and receiver operating characteristic analysis were performed. RESULTS: There was substantial interreader agreement among PET/MR imaging scores (κ = 0.634; 95% CI, 0.605-0.663). PET/MR imaging scores showed a strong association with treatment failure by univariate association analysis, with P < .001 for the primary site, neck lymph nodes, and combined sites. Receiver operating characteristic curves of PET/MR imaging scores versus treatment failure indicated statistically significant diagnostic accuracy (area under curve range, 0.864-0.987; P < .001). CONCLUSIONS: Simultaneous PET/MR imaging has excellent discriminatory performance for treatment outcomes of head and neck malignancy when the Neck Imaging Reporting and Data System is applied. PET/MR imaging could play an important role in surveillance imaging for head and neck cancer.

A comparison of preincisional and postincisional ultrasound guided transversus abdominis plane block.

BACKGROUND AND AIMS: Transversus abdominis plane blocks are part of the multimodal analgesia used for lower abdominal surgeries.Our aim of this study was to compare the analgesic efficacy of preincisional and postincisional TAP blocks in patients undergoing total abdominal hysterectomies. MATERIAL AND METHODS: 54 American Society of Anesthesiologists physical status I and II patients aged between 30 and 60 years who underwent a total abdominal hysterectomy under spinal anesthesia in our hospital were chosen for the study. Alternate patients satisfying the inclusion criteria were either given a preincisional or postincisional transversus abdominis plane block bilaterally. Postoperatively, the numeric pain intensity scale was observed, along with nausea, vomiting, and sedation scores. RESULTS: Pain scores were significantly lower (P < 0.05) in the preincisional TAP block group from the 2nd postoperative hour onwards till 12 h, and thereafter it was comparable between both the groups. The total morphine requirement was significantly less in the preincisional TAP group (P-value 0.001). Also, the mean time to the first request for morphine was significantly longer in patients belonging to the preincisional TAP block group (P-value of 0.002). There were no significant differences in the sedation scores postoperatively, except at the 4th hour, where it was significantly higher (P-value of 0.024) in the postincisional TAP group. Post operative nausea and vomiting was significantly higher and so the dose of the antiemetic used was also observed to be more in the postincisional TAP block group. CONCLUSION: Preincisional TAP blocks are more effective than postincisional ones with better analgesia and lesser side effects, for total abdominal hysterectomies.

Rescuing mitochondria in traumatic brain injury and intracerebral hemorrhages - A potential therapeutic approach.

Mitochondria are dynamic organelles responsible for cellular energy production. Besides, regulating energy homeostasis, mitochondria are responsible for calcium homeostasis, signal transmission, and the fate of cellular survival in case of injury and pathologies. Accumulating reports have suggested multiple roles of mitochondria in neuropathologies, neurodegeneration, and immune activation under physiological and pathological conditions. Mitochondrial dysfunction, which occurs at the initial phase of brain injury, involves oxidative stress, inflammation, deficits in mitochondrial bioenergetics, biogenesis, transport, and autophagy. Thus, development of targeted therapeutics to protect mitochondria may improve functional outcomes following traumatic brain injury (TBI) and intracerebral hemorrhages (ICH). In this review, we summarize mitochondrial dysfunction related to TBI and ICH, including the mechanisms involved, and discuss therapeutic approaches with special emphasis on past and current clinical trials.

Acute metronidazole-induced neurotoxicity: an update on MRI findings.

AIM: To describe a series of 10 cases of metronidazole-induced neurotoxicity (MIN) and review the established literature to better define its clinical and imaging findings. MATERIALS AND METHODS: The clinical presentations and magnetic resonance imaging (MRI) images of 10 patients with clinically diagnosed MIN were reviewed retrospectively. A review of an additional 31 cases from prior published case series was performed. RESULTS: The median age of patients from the authors' institutions with MIN was 54 (range 8-84) years. The median cumulative dose of metronidazole received was 64.5 g (range 7.5-1,380 g). Common presenting neurological symptoms were ataxia (n=6) and altered mental status (n=3). All of the patients (n=10) had symmetric T2 hyperintense lesions in the dentate nuclei at presentation. Other involved structures included the midbrain, corpus callosum, pons, medulla, basal ganglia, and supratentorial white matter. True restricted diffusion was seen in the corpus callosum (n=6). Symptoms resolved in all patients except for one. For the patients with available follow up MRI (n=4), the observed lesions resolved. CONCLUSION: MIN affects both adult and paediatric patients. Symptoms typically occur after prolonged exposure to the antibiotic, but can occur at low cumulative doses. Most frequently involved structures are the dentate nucleus, midbrain, and splenium corpus callosum. Restricted diffusion within the corpus callosum is likely due to cytotoxic oedema. Symptoms typically resolve after cessation of metronidazole, and lesions typically resolve on follow-up imaging.

Hyperpolarized relaxometry based nuclear T1 noise spectroscopy in diamond.

The origins of spin lifetimes in quantum systems is a matter of importance in several areas of quantum information. Spectrally mapping spin relaxation processes provides insight into their origin and motivates methods to mitigate them. In this paper, we map nuclear relaxation in a prototypical system of [Formula: see text] nuclei in diamond coupled to Nitrogen Vacancy (NV) centers over a wide field range (1 mT-7 T). Nuclear hyperpolarization through optically pumped NV electrons allows signal measurement savings exceeding million-fold over conventional methods. Through a systematic study with varying substitutional electron (P1 center) and [Formula: see text] concentrations, we identify the operational relaxation channels for the nuclei at different fields as well as the dominant role played by [Formula: see text] coupling to the interacting P1 electronic spin bath. These results motivate quantum control techniques for dissipation engineering to boost spin lifetimes in diamond, with applications including engineered quantum memories and hyperpolarized [Formula: see text] imaging.

Correlates of physical function among stroke survivors: an examination of the 2015 BRFSS.

OBJECTIVES: To identify the characteristics of stroke survivors with poor physical function. STUDY DESIGN: Cross-sectional. METHODS: Secondary data analyses were performed with the 2015 Behavioral Risk Factor Surveillance System data set. Unadjusted and adjusted logistic regressions were employed to determine the correlates of poor physical function in stroke survivors. Self-reported difficulty with walking and stairs was used as a proxy for physical function. Characteristics such as age, race, sex, difficulty doing errands alone, difficult dressing or bathing alone, health care coverage, time since last routine checkup, and reported financial difficulty with regard to health care access were examined as contributing factors to physical function. RESULTS: Approximately half of all stroke survivors reported having difficulty with walking and stairs (50.3%). As expected, the odds of reporting difficulty with walking and stairs were higher among stroke survivors aged 40 years and above (p < 0.0001). Interestingly, black/African American and multiracial respondents had higher odds of reporting difficulty with walking and stairs than whites, whereas Hispanic respondents had lower odds of reporting difficulty with walking and stairs than whites (p < 0.0001). Further analyses revealed that the disparity of physical function was preserved (p < 0.0001) after adjusting for age, race, sex, education level, family income, marital status, employment status, health insurance status, affordability of healthcare, and length of time from last doctor's visit. CONCLUSIONS: There were racial/ethnic disparities in physical function. Specifically, blacks/ African Americans had a 5.6% increase in the odds of reporting difficulty with walking and stairs than whites. Moreover, Hispanics reported significantly fewer problems than whites. Overall, similar sociocultural patterns in non-stroke and stroke populations were observed in this study.

Diarrheagenic Escherichia coli infections among the children of Andaman Islands with special reference to pathotype distribution and clinical profile.

Diarrhoeagenic E. coli (DEC) is one of the most common causes of diarrhoeal death in children less than five years globally. It is responsible for 30%-40% of all diarrhoeal episodes in developing countries. It is estimated that 0.12million children died of diarrhoea caused by DEC in 2011 globally. There is no baseline data on the occurrence of DEC diarrhoea in Andaman Islands, the remote islands of India. The study is particularly important as these strains are the emerging enteric pathogen in both developed and developing countries. DEC was screened from E. coli isolates obtained from diarrhoeal stool samples by multiplex PCR with specific primers using stasndard protocols. During the study period, among the 1394 stool samples collected, 95 (6.82%) patients were found infected with DEC. Of the 97 isolates from 95 patients, 68 (70.1%) were EAEC, 19 (19.6%) were EPEC and 10 (10.3%) were ETEC. Of the 19 EPEC isolates, 63.2% were atypical EPEC which is the emerging enteric pathogen among the children in developing as well as developed countries. More than 80% of the patients had watery diarrhoea and 6% of them had invasive diarrhoea. Persistent diarrhoea was also found in three infected children. This study documents the occurrence and type of DEC diarrhoea in Andaman Islands first time and highlights the significant proportions of E. coli diarrhoea being caused by EAEC and atypical EPEC strains.

Carotid Bulb Webs as a Cause of "Cryptogenic" Ischemic Stroke.

BACKGROUND AND PURPOSE: Carotid webs are intraluminal shelf-like filling defects at the carotid bulb with recently recognized implications in patients with recurrent ischemic stroke. We sought to determine whether carotid webs are an under-recognized cause of "cryptogenic" ischemic stroke and to estimate their prevalence in the general population. MATERIALS AND METHODS: A retrospective review of neck CTA studies in young patients with cryptogenic stroke over the past 6 years (n = 33) was performed to determine the prevalence of carotid webs compared with a control group of patients who received neck CTA studies for reasons other than ischemic stroke (n = 63). RESULTS: The prevalence of carotid webs in the cryptogenic stroke population was 21.2% (95% CI, 8.9%-38.9%). Patients with symptomatic carotid webs had a mean age of 38.9 years (range, 30-48 years) and were mostly African American (86%) and women (86%). In contrast, only 1.6% (95% CI, 0%-8.5%) of patients in the control group demonstrated a web. Our findings demonstrate a statistically significant association between carotid webs and ischemic stroke (OR = 16.7; 95% CI, 2.78-320.3; P = .01). CONCLUSIONS: Carotid webs exhibit a strong association with ischemic stroke, and their presence should be suspected in patients lacking other risk factors, particularly African American women.

Periprosthetic Bone Remodeling After Novel Short-Stem Neck-Sparing Total Hip Arthroplasty.

BACKGROUND: Short femoral stems have been designed with the aims of reducing proximal bone loss, improving load transfer, and increasing compressive loads at the medial proximal femoral calcar. This study examines bone mineral density (BMD) changes associated with a novel neck sparing short femoral stem design. METHODS: The study was a prospective, single-center, multi-investigator consecutive series, which assessed bone-remodeling changes after insertion of the MSA Stem (Global Orthopaedic Technology). Dual-energy X-ray absorptiometry scans were performed preoperatively and postoperatively at 6, 12, and 24 months assessing the BMD at the 7 Gruen zones. The secondary objectives assessed were the Harris Hip Score, 12-Item Short Form Health Survey preoperatively, and perioperative complications. RESULTS: Thirty-nine total hip arthroplasties were performed on 37 patients, with 27 patients completing the 24-month dual-energy X-ray absorptiometry scan. The overall preoperative baseline BMD was 0.2. At 6 months, the Gruen zone BMD had increased significantly in all zones in comparison to the preoperative mean BMD. Between 6 months and 24 months, there were only slight changes in the Gruen zones, with small gains in zones 1-2 and zones 4-6, with no zone showing a significant decrease. The Harris Hip Score improved from a preoperative mean of 39.7-75.3, whereas the 12-Item Short Form Health Survey score also improved from 32.6 to 49 at 24 months. However, 5 patients had aseptic loosening requiring revision surgery (4 femoral and 1 acetabular component). CONCLUSION: Short-stem neck-sparing femoral stem prosthesis has the capacity to address the stress-shielding problem identified in femoral stems. However, the high early revision rate is a significant issue.

Postoperative Imaging Findings following Sigmoid Sinus Wall Reconstruction for Pulse Synchronous Tinnitus.

BACKGROUND AND PURPOSE: Transmastoid sigmoid sinus wall reconstruction is a surgical technique increasingly used for the treatment of pulsatile tinnitus arising from sigmoid sinus wall anomalies. The imaging appearance of the temporal bone following this procedure has not been well-characterized. The purpose of this study was to evaluate the postoperative imaging appearance in a group of patients who underwent this procedure. MATERIALS AND METHODS: The medical records of 40 consecutive patients who underwent transmastoid sigmoid sinus wall reconstruction were reviewed. Thirteen of 40 patients underwent postoperative imaging. Nineteen CT and 7 MR imaging examinations were assessed for the characteristics of the materials used for reconstruction, the impact of these on the adjacent sigmoid sinus, and complications. RESULTS: Tinnitus resolved in 38 of 40 patients. Nine patients were imaged postoperatively for suspected complications, including dural sinus thrombosis, facial swelling, and wound drainage. Two patients underwent imaging for persistent tinnitus, and 2, for development of tinnitus on the side contralateral to the side of surgery. The materials used for reconstruction (NeuroAlloderm, HydroSet, bone pate) demonstrated characteristic imaging appearances and could be consistently identified. In 5 of 13 patients, there was extrinsic compression of the sigmoid sinus by graft material. Dural sinus thrombosis occurred in 2 patients. CONCLUSIONS: The imaging findings following sigmoid sinus wall repair are characteristic. Graft materials may result in extrinsic compression of the sigmoid sinus, and this finding may be confused with dural venous thrombosis. Awareness of the imaging characteristics of the graft materials used enables this differentiation.

The "boomerang" malleus-incus complex in congenital aural atresia.

"Boomerang" malleus-incus fusion deformity is identified on axial high-resolution CT in a subset of patients with congenital aural atresia, and it is associated with an absent incudostapedial joint and stapes capitulum and attachment of the incus to the tympanic segment of the facial nerve canal. Twelve patients with this deformity were identified on a retrospective review of imaging from a cohort of 673 patients with congenital aural atresia, with surgical confirmation in 9 of these patients. Eight of 9 patients underwent partial ossicular replacement prosthesis reconstruction with improvement in hearing outcome. We hypothesize that the boomerang anomaly represents a more severe ossicular anomaly than is normally seen in congenital aural atresia, arising from an arrest earlier in the embryonic development of the first and second branchial arch. This has potentially important implications for surgical planning because hearing outcomes with placement of prosthesis may not be as good as with conventional atresia surgery, in which reconstruction is performed with the patient's native ossicular chain.

Dynamic CT for parathyroid disease: are multiple phases necessary?

BACKGROUND AND PURPOSE: A 4D CT protocol for detection of parathyroid lesions involves obtaining unenhanced, arterial, early, and delayed venous phase images. The aim of the study was to determine the ideal combination of phases that would minimize radiation dose without sacrificing diagnostic accuracy. MATERIALS AND METHODS: With institutional review board approval, the records of 29 patients with primary hyperparathyroidism who had undergone surgical exploration were reviewed. Four neuroradiologists who were blinded to the surgical outcome reviewed the imaging studies in 5 combinations (unenhanced and arterial phase; unenhanced, arterial, and early venous; all 4 phases; arterial alone; arterial and early venous phases) with an interval of at least 7 days between each review. The accuracy of interpretation in lateralizing an abnormality to the side of the neck (right, left, ectopic) and localizing it to a quadrant in the neck (right or left upper, right or left lower) was evaluated. RESULTS: The lateralization and localization accuracy (90.5% and 91.5%, respectively) of the arterial phase alone was comparable with the other combinations of phases. There was no statistically significant difference among the different combinations of phases in their ability to lateralize or localize adenomas to a quadrant (P = .976 and .996, respectively). CONCLUSIONS: Assessment of a small group of patients shows that adequate diagnostic accuracy for parathyroid adenoma localization may be achievable by obtaining arterial phase images alone. If this outcome can be validated prospectively in a larger group of patients, then the radiation dose can potentially be reduced to one-fourth of what would otherwise be administered.

Imaging findings in MR imaging-guided focused ultrasound treatment for patients with essential tremor.

BACKGROUND AND PURPOSE: MR imaging-guided focused sonography surgery is a new stereotactic technique that uses high-intensity focused sonography to heat and ablate tissue. The goal of this study was to describe MR imaging findings pre- and post-ventralis intermedius nucleus lesioning by MR imaging-guided focused sonography as a treatment for essential tremor and to determine whether there was an association between these imaging features and the clinical response to MR imaging-guided focused sonography. MATERIALS AND METHODS: Fifteen patients with medication-refractory essential tremor prospectively gave consent; were enrolled in a single-site, FDA-approved pilot clinical trial; and were treated with transcranial MR imaging-guided focused sonography. MR imaging studies were obtained on a 3T scanner before the procedure and 24 hours, 1 week, 1 month, and 3 months following the procedure. RESULTS: On T2-weighted imaging, 3 time-dependent concentric zones were seen at the site of the focal spot. The inner 2 zones showed reduced ADC values at 24 hours in all patients except one. Diffusion had pseudonormalized by 1 month in all patients, when the cavity collapsed. Very mild postcontrast enhancement was seen at 24 hours and again at 1 month after MR imaging-guided focused sonography. The total lesion size and clinical response evolved inversely compared with each other (coefficient of correlation = 0.29, P value = .02). CONCLUSIONS: MR imaging-guided focused sonography can accurately ablate a precisely delineated target, with typical imaging findings seen in the days, weeks, and months following the treatment. Tremor control was optimal early when the lesion size and perilesional edema were maximal and was less later when the perilesional edema had resolved.

Dorsal thoracic arachnoid web and the "scalpel sign": a distinct clinical-radiologic entity.

Arachnoid webs are intradural extramedullary bands of arachnoid tissue that can extend to the pial surface of the spinal cord, causing a focal dorsal indentation of the cord. These webs tend to occur in the upper thoracic spine and may produce a characteristic deformity of the cord that we term the "scalpel sign." We describe 14 patients whose imaging studies demonstrated the scalpel sign. Ten of 13 patients who underwent MR imaging demonstrated T2WI cord signal-intensity changes, and 7 of these patients also demonstrated syringomyelia adjacent to the level of indentation. Seven patients underwent surgery, with 5 demonstrating an arachnoid web as the cause of the dorsal indentation demonstrated on preoperative imaging. Although the webs themselves are rarely demonstrated on imaging, we propose that the scalpel sign is a reliable indicator of their presence and should prompt consideration of surgical lysis, which is potentially curative.

Utility of CT angiography in the identification and characterization of supraclinoid internal carotid artery blister aneurysms.

BACKGROUND AND PURPOSE: Blister aneurysms of the supraclinoid ICA represent a rare but potentially catastrophic cause of SAH, often presenting both diagnostic and therapeutic dilemmas. We explore the utility of CTA in the identification and characterization of ICA blister aneurysms. MATERIALS AND METHODS: We performed a retrospective review of catheter cerebral angiograms obtained at our institution over a 12-month period for evaluation of SAH, identifying 6 cases of ICA blister aneurysms. All patients underwent CTA and DSA for evaluation of SAH. The reports from the CTA and DSA studies were reviewed to identify aneurysms correctly diagnosed prospectively. Retrospective review of the CTA and DSA images was also performed. Review of the interpretations and images was performed for any follow-up studies. RESULTS: All 6 patients presented with SAH, diagnosed by head CT. All patients subsequently underwent CTA prior to DSA evaluation. All 6 aneurysms were identified prospectively on initial DSA imaging. Of the 6 blister aneurysms, 4 (67%) were identified prospectively; and 5 (83%), retrospectively on CTA. All 6 patients underwent endovascular treatment with stent placement. Four of the 6 aneurysms underwent follow-up CTA (range, 9-22 days), including the 2 aneurysms that had been unidentifiable preprocedurally. All 4 blister aneurysms were seen postprocedurally by DSA. Three of these 4 (75%) residual aneurysms were detected by CTA (both prospectively and retrospectively). CONCLUSIONS: In the presence of SAH and otherwise negative findings on CTA, a catheter cerebral angiogram should be performed to absolutely exclude an ICA blister aneurysm.

The evolution of the anatomically modern or advanced Homo sapiens: time, place, process, affinities and variations.

This paper surveys the opinions expressed in the recent literature on the origins of the anatomically- modern Homo sapiens, and reviews the evidence from cranial and dental morphology argued by proponents of opposing views to support their case. It also critically analyses problems facing the interpretation of the evidence in arriving at a definitive conclusion to the debate.

The impact of expansive arterial remodeling on clinical presentation in carotid artery disease: a multidetector CT angiography study.

BACKGROUND AND PURPOSE: Atherosclerotic arterial remodeling has been described in the coronary circulation but has not been studied extensively for carotid atherosclerosis. The purpose of our study was to examine the association between carotid artery remodeling and clinical presentation in patients with significant stenosis by using multidetector row CT (MDCT). MATERIALS AND METHODS: One hundred eight patients with >or=50% stenosis (North American Symptomatic Carotid Endarterectomy Trial criteria) by MDCT angiography between January 2004 and June 2006 were identified. The study group included 37 symptomatic (65.9 +/- 13.0 years; 12 women; stenosis, 81.5 +/- 12.2%; 17 with stroke; 15 with transient ischemic attack; 5 with amaurosis fugax) and 71 asymptomatic patients (70.5 +/- 10.5 years; 28 women; stenosis, 78.8 +/- 11.1%). Remodeling ratio (RR) was calculated by dividing the outer vessel circumference at the site of greatest stenosis by a normal reference-segment vessel circumference. Maximum vessel thickness (MxVT) and eccentricity index (EI) of the plaque, defined as maximal thickness/minimal thickness at the site of greatest luminal narrowing, were also determined. Data were analyzed by using an independent t test. RESULTS: The RR was significantly higher in symptomatic patients (1.64 +/- 0.44) than in asymptomatic patients (1.41 +/- 0.5) (P=.02). There was no significant difference in MxVT in symptomatic (5.9 +/- 2.1 mm) and asymptomatic patients (5.6 +/- 2.4 mm) (P=.45) and no significant difference in EI (symptomatic, 4.7 +/- 2.7; asymptomatic, 4.3 +/- 2.2; P=.38). CONCLUSION: In this series of subjects with significant internal carotid artery stenosis, expansive carotid remodeling was significantly greater in patients with cerebral ischemic symptoms than in asymptomatic patients. The extent of expansive remodeling may indicate underlying atherosclerotic plaque vulnerability. MDCT has a role in the evaluation of carotid artery disease beyond examining luminal stenosis.

Extramedullary hematopoiesis involving the bilateral lacrimal fossae.

Extramedullary hematopoiesis is a complication of a number of myeloproliferative disorders. MR imaging of the orbits was performed in a patient with bilateral orbital swelling with known myeloproliferative disorder and myelofibrosis. The study revealed symmetric, bilateral enhancing masses in the lacrimal fossae extending into the nasolacrimal ducts. Biopsy demonstrated sclerotic extramedullary hematopoietic tumor.

Psychrobacter salsus sp. nov. and Psychrobacter adeliensis sp. nov. isolated from fast ice from Adelie Land, Antarctica.

Nine psychrotolerant bacteria were isolated from fast ice in the middle of Geologie Archipelago, Adelie Land, Antarctica and were categorized into two groups, based on their SDS-PAGE profiles. Representatives from each of the two groups, namely strains DD 48T and SJ 14T exhibited phenotypic and chemotaxonomic characteristics confirming to the genus Psychrobacter. The 16S rRNA gene sequence indicated that the two isolates are closely related to each other and to the already reported fifteen species of Psychrobacter. Detailed studies on the phenotypic characteristics, chemotaxonomic properties and phylogenetic analysis of strains DD 48T and SJ 14T indicated that they are distinctly different from each other and the reported species of Psychrobacter. At the DNA-DNA hybridisation level, the two species exhibit less than 70% similarity. Thus, strains DD 48T and SJ 14T are identified as new species of the genus Psychrobacter for which the names Psychrobacter salsus sp. nov. and Psychrobacter adeliensis sp. nov. respectively are proposed.