Posterior Location Research Articles

Neuronal cell types, projections, and spatial organization of the central amygdala.

The central amygdala (CEA) has been richly studied for interpreting function and behavior according to specific cell types and circuits. Such work has typically defined molecular cell types by classical inhibitory marker genes; consequently, whether marker-gene-defined cell types exhaustively cover the CEA and co-vary with connectivity remains unresolved. Here, we combined single-cell RNA sequencing, multiplexed fluorescent in situ hybridization, immunohistochemistry, and long-range projection mapping to derive a "bottom-up" understanding of CEA cell types. In doing so, we identify two major cell types, encompassing one-third of all CEA neurons, that have gone unresolved in previous studies. In spatially mapping these novel types, we identify a non-canonical CEA subdomain associated with Nr2f2 expression and uncover an Isl1-expressing medial cell type that accounts for many long-range CEA projections. Our results reveal new CEA organizational principles across cell types and spatial scales and provide a framework for future work examining cell-type-specific behavior and function.

Apex posterior angulation of the humerus: A characterization of normal sagittal plane anatomy with implications for surgical fixation

IntroductionAn understanding of the sagittal plane morphology of the humerus is relevant during surgical fixation of humeral fractures but is not well described in the literature. The purpose of this study was to better characterize the native sagittal plane morphology of the humerus. Materials and methods170 patients with uninjured full length lateral humerus radiographs were retrospectively evaluated. The angle between the proximal humeral diaphyseal axis and the distal humeral diaphyseal axis was identified and measured. The proximal axis was defined by two points equidistant from the anterior and posterior cortex 10 mm and 100 mm distal to the metaphyseal flare, and the distal axis by two points at 10 mm and 50 mm proximal to the capitellum/trochlea. The relative location of the center of rotation of angulation (CORA) was calculated as a percentage of humeral length. Results114 radiographs were included in the analysis (66 right humeri, 48 left humeri). The average apex posterior angulation was 6.5 +/- 2.9°. The CORA occurred at an average of 80% (SD+/-13%) of the length of the humerus (proximal to distal). Total humeral length and absolute distance to CORA were greater in males compared to females (364 ± 50 mm versus 326 ± 30 mm; p<0.001; 290 ± 68 mm versus 260 ± 48 mm; p=0.003), but there were no significant sex differences with respect to magnitude of the apex posterior angulation (p=0.077) or location of CORA as a percentage of total humeral length (p=0.916). There were no statistically significant associations between age and total humeral length (p=0.056), distance to CORA (p=0.130), location of CORA as percentage of total humeral length (p=0.753), or magnitude of angulation (p=0.075). ConclusionAn apex posterior bow consistently exists in the distal one-quarter of the humerus that is consistent across ages and between sexes. This normal anatomic bow is important to recognize to avoid an extension malreduction and has implications for implant fit and contouring.

Atypical fractures of the ulna: Effect of bowing of the ulna on fracture location and occurrence

IntroductionUlnar fractures associated with long-term bisphosphonate (BPs) therapy are rare, and the nature and extent of this potential risk remains unknown. Although ulna is generally considered a “straight bone”, it actually features a bow anatomically. For this reason, we speculated that ulnar bow may have a role in the development of atypical ulnar fractures (AUFs). Therefore, we compared the location and depth of ulnar bow between AUF patients and patients with atypical fractures other than the ulna. We aimed to answer: (1) whether a correlation exists between the location of the ulna bow and the location of AUFs, (2) whether the degree of ulnar bow affects the occurrence of AUFs. HypothesisUlnar bowing could play a critical role in the location and occurrence of AUFs. MethodsWe retrospectively reviewed the radiographs and medical records of 64 patients with atypical fractures admitted to our department between May 2010 to July 2020. The bow of the ulna was measured using anteroposterior (AP) and lateral radiographs. Bone angulation was described as apex of deformity, with apex lateral bow designated as AP plane bowing and apex posterior bow marked as lateral plane bowing. ResultsIn all patients with atypical fractures, bow locations were measured at the proximal third level to the index line in 68% of AP plane and 72% of lateral plane. In patients with AUFs, fracture sites occurred in the range of 20% to<40%, except in one patient. Fracture site versus apex lateral bow location and fracture site versus apex posterior bow location showed a statistically significant correlation coefficient of 0.81 (p<0.001) and 0.69 (p=0.003), respectively. In lateral plane, there was a significant difference between AUF patients and patients with atypical fractures other than the ulna in ulnar bow depth (p=0.014). However, no statistically significant differences were found in AP plane (p=0.110). DiscussionIn AUFs, fracture site was highly correlated with ulnar bowing location, and, as the degree of apex posterior bow increased, occurrence of AUFs increased. These findings are helpful in understanding the role of bowing as the ulnar geometry in the development of AUF and early identification of the location of suspicious AUF. Level of evidenceIV.

The "Three Cherries Technique" for glaucoma drainage devices

Small sponges are used to apply antimetabolites in order to reduce the risk of fibrosis in filtering glaucoma surgery. Due to the posterior location of the filtering bleb in glaucoma drainage implants, there is arisk that the sponges can dislocate in this area and cannot be retrieved after the exposure time has elapsed. We use the "three cherries technique" to minimize the risk. The term "three cherries technique" was coined by us and has not been used before in the literature. The three sponges that are used for mitomycinC application are each connected by single button sutures with a7.0 vicryl thread. At the end of the application time, the sponges can be quickly removed by pulling the thread.

Influence of anterior tumor location on survival after resection of lung cancer invading the thoracic inlet (Pancoast tumors)

ObjectiveSuperior sulcus tumors are a challenging subset of non–small cell lung carcinomas invading the thoracic inlet. In this study, we determined whether the location of the tumor along the first rib had an influence on survival. MethodsWe performed a review of 92 consecutive patients undergoing surgery for non–small cell lung carcinomas invading the thoracic inlet between January 1996 and June 2021. Tumor location was categorized into anterior and posterior based on predefined zones. ResultsIn total, 21 tumors were located anteriorly (23%) and 71 posteriorly (77%). The rate of R0 resection (81% vs 87%; P = .4) and pathological complete response to induction therapy (33% vs 37%; P = .8) were similar between locations. After a median follow-up of 5.8 years (range, 0.8-24 years), 49 patients died for an overall survival of 48% (95% CI, 38%-59%) at 5 years. The 5-year survival was favorably influenced by R0 (vs R1) resection (51% vs 29%; P = .02), pathological complete response (vs no pathological complete response) (69% vs 31%; P = .03), posterior (vs anterior) location (56% vs 22%; P = .01), and ≤60 (vs >60) years of age (61% vs 37%; P = .007). Compared with posterior tumors, anterior tumors were associated with higher risk of systemic recurrence and significantly greater survival benefit from pathological complete response. Anterior tumors remained an independent predictor of worse survival in multivariate analysis (hazard ratio, 2.3; 95% CI, 1.2-4.5; P = .01). ConclusionsThe anatomical location of the tumor affects survival after resection of non–small cell lung carcinomas invading the thoracic inlet. Anterior tumors have greater propensity to metastasize and may derive greater benefit from optimal systemic therapy than posterior tumors.

GSOR11 Presentation Time: 9:55 AM: 3D Printing Enhanced GYN Brachytherapy: From Novice to Expert in One Print with the TARGIT-FX

<h3>Purpose</h3> It is well established in cervical brachytherapy that the addition of interstitial (IS) needles to intra-cavitary (IC) applicators can significantly enhance dosimetry by improving target coverage without increasing normal tissues doses. Accurate placement of interstitial needles requires significant technical skill and imaging guidance proficiency, thereby limiting the benefits to a subset of practitioners and patients. Available commercial combined IC/IS applicators restrict the available needle positions to often unsatisfactory locations for optimized dosimetry. We have developed and further improved our supplemental templates that attach to the tandem applicator and guides needles to optimized positions for different tumor topologies. This new TARGIT-FX (Tandem Anchored Radially Guiding Interstitial Template - Flexible eXtended) is 3D printed from biologically compatible materials, can be steam sterilized and provides multiple degrees of flexibility to simplify and facilitate interstitial needle insertion. <h3>Materials/Methods</h3> Our previously described IS needle guide (TARGIT), which facilitates placement of complementary needles in a tandem and ovoid implant, was redesigned with the purported goal of added flexibility and ease of use. The tandem attached small template was extended all the way to the vaginal introitus to allow needle insertion from outside the patient. The number of needle position options increased from four to nine to better cover a wider range of clinical situations: three paired width options ((2.0, 1.5 and 1.25 cm width) at the level of point A and three individual posterior locations (figure, insert E). The new design has been used clinically for 14 different patient implants During the procedure, the tandem is first inserted (Figure 1A), the TARGIT-FX is then slid over in position and secured over the tandem (Fig. 1B-C); after the ovoids are placed, needles can be inserted from outside the patient in the selected locations as clinically required (Fig. 1 D). Figure 1E show all the needle potential positions. The procedure time and relevant dosimetric parameters were tracked, as well as usability. <h3>Results</h3> The procedure time with the TARGIT-FX was decreased to 24 min from a benchmark of 29 min with the older TARGIT design (average over 68 implants). The V100% remained similar with 92.2% as compared to the 90.2% TARGIT benchmark, while organs at risk remained within constraints. The main goals of flexibility were achieved as follows: the larger number of needle positions enabled greater customization and live changes during the procedure based on the patient anatomy as visualized on live transrectal ultrasound. The ease of use, in particular the ability to reliably insert and position needles from outside the patient, enabled our medical residents under supervision to confidently perform the entire combined IS/IC implants and even first fraction implants. In addition, the new design enabled in one particular case the addition of a needle after the initial procedure, following the planning CT, as the needle could be inserted from outside with the patient lying on the CT table in scanning position. The reliability and consistency of needle placement with the new design may further increase speed since ultrasound imaging during the procedure may be reduced or omitted. <h3>Conclusion</h3> The 3D printed TARGIT-FX enables simple, fast and reliable interstitial needle insertion for combined tandem and ovoid and IS implants. The flexibility of the design enables new or less experienced users to improve the degrees of freedom and dosimetry of their combined IC/IS implants.

“But It Is Only Menstrual Pain”—A Systematic Literature Study on Diagnosis in Endometriosis

BackgroundEndometriosis is a disease that affects approximately 1 in 10 women, and in Sweden, it is estimated that 200,000 women suffer from this debilitating disease. Endometriosis is an illness that cannot always be diagnosed via medical imaging. In this literary review, we will study the ability of magnetic resonance imaging (MRI) to detect endometriosis in the whole abdomen. ObjectiveThe objective was to compare MRI with the golden standard, laparoscopy. MethodsThis literary review consists of 15 research papers: 10 prospective studies, 4 retrospective studies, and 1 interrater agreement study with laparoscopy as a reference standard. ResultMRI can in a higher degree correctly diagnose deep infiltrating endometriosis than laparoscopy, more specifically around the more posterior locations. The more superficial anterior endometriosis MRI did not reach the same results as other medical imaging modalities. What also matters in the diagnosis of endometriosis is the knowledge and experience of the radiographer examining the images. ConclusionOur study shows that MRI can become the main medical imaging tool and become the new golden standard instead of laparoscopy. However, the knowledge about endometriosis needs to increase, both within the medical imaging department and the pathology department. New techniques and specialized protocols need to be developed for MRI to become the primary diagnostic tool for the diagnosis of endometriosis.

Risk Factors for Progression and Toxicity after Preoperative Radiosurgery for Resected Brain Metastases: A PROPS-BM Multicenter Cohort Study

<h3>Purpose/Objective(s)</h3> Preoperative (preop) stereotactic radiosurgery (SRS) is a feasible alternative to postoperative (postop) SRS with potential benefits in adverse radiation effect (ARE) and meningeal disease (MD) compared to postop SRS. The goal of this study was to determine risk factors for progression and toxicity after preop SRS in an expanded multicenter cohort. <h3>Materials/Methods</h3> Patients with brain metastases (BM) from solid cancers, of which at least 1 lesion was treated with preop SRS and underwent planned resection were included from 6 institutions. SRS to synchronous intact BM was allowed. Exclusion criteria included classically radiosensitive or non-solid cancers and prior or planned whole brain radiotherapy (WBRT). SRS dose, fractionation, and interval between preop SRS and surgery was per individual institutional protocol. Intracranial outcomes were estimated using cumulative incidence with competing risk of death. Radiographic MD was categorized as nodular (nMD) or classical "sugarcoating" (cMD). <h3>Results</h3> The cohort consisted of 378 patients with 389 preop SRS treated index lesions. Most patients (61.1%) had a single BM, underwent gross total resection (GTR, 95.4%), and had non-small cell lung (NSCLC, 47.9%), breast (16.1%), or melanoma (11.4%) cancer. Median dose was 15 Gy in 1 fraction to a median gross tumor volume (GTV) of 10.1 cc. Median interval between preop SRS and surgery was 2 days. Median cranial imaging follow-up interval was 9.5 months overall and 17.5 months for alive patients. The 2-year cavity local recurrence (LR) rate was 14.5%. Multivariable analysis (MVA) for LR demonstrated subtotal resection (STR, vs. GTR), single fraction SRS (vs. fractionated), larger GTV, gastrointestinal (GI) primary (vs. NSCLC), active systemic disease, and piecemeal resection (vs. en bloc) to be associated with higher risk of LR. Of note, interval between preop SRS and surgery was not significant. The 2-year any grade ARE rate was 7.7%. MVA for ARE demonstrated only larger planning target volume (PTV) margin expansion as associated with higher risk of ARE. The 2-year rate of MD was 5.6%. Most MD (76%) was classical type, with the remainder being nodular type. MVA for MD demonstrated STR (vs. GTR) and breast or melanoma histology (vs. NSCLC) as associated with higher risk of MD. Of note, posterior fossa location and type of surgical resection were not significant. <h3>Conclusion</h3> Preop SRS demonstrates overall excellent rates of cavity LR, ARE, and MD in this expanded multicenter cohort study. We have identified several tumor and treatment factors that are significantly associated with risk of cavity LR, ARE, and MD after treatment with preop SRS. Minimizing likelihood of STR and treating with fractionated preop SRS for larger higher risk tumors may lead to improved outcomes. A randomized trial of preop versus postop SRS is currently being designed (NRG BN012).

Laparoscopic versus open repair of perforated peptic ulcers: analysis of outcomes and identification of predictive factors of conversion

BackgroundThe surgical treatment for perforated peptic ulcers (PPUs) can be safely performed laparoscopically. This study aimed to compare the outcomes of patients who received different surgical approaches for PPU and to identify the predictive factors for conversion to open surgery.MethodsThis retrospective study analyzed patients treated for PPUs from 2002 to 2020. Three groups were identified: a complete laparoscopic surgery group (LG), a conversion to open group (CG), and a primary open group (OG). After univariate comparisons, a multivariate analysis was conducted to identify the predictive factors for conversion.ResultsOf the 175 patients that underwent surgery for PPU, 104 (59.4%) received a laparoscopic-first approach, and 27 (25.9%) required a conversion to open surgery. Patients treated directly with an open approach were older (p < 0.0001), had more comorbidities (p < 0.0001), and more frequently had a previous laparotomy (p = 0.0001). In the OG group, in-hospital mortality and ICU need were significantly higher, while the postoperative stay was longer. Previous abdominal surgery (OR 0.086, 95% CI 0.012–0.626; p = 0.015), ulcer size (OR 0.045, 95% CI 0.010–0.210; p < 0.0001), and a posterior ulcer location (OR 0.015, 95% CI 0.001–0.400; p = 0.012) were predictive factors for conversion to an open approach.ConclusionThis study confirms the benefits of the laparoscopic approach for the treatment of PPUs. Previous laparotomies, a greater ulcer size, and a posterior location of the ulcer are risk factors for conversion to open surgery during laparoscopic repair.

LUNG CANCER IS NOT ALWAYS THE ANSWER: EXPLORING THE DIFFERENTIAL DIAGNOSIS OF THORACIC MASSES

LUNG CANCER IS NOT ALWAYS THE ANSWER: EXPLORING THE DIFFERENTIAL DIAGNOSIS OF THORACIC MASSES

Lateralized tactile stimulation during NREM sleep globally increases both slow and fast frequency activities.

Slow frequency activity during non-rapid eye movement (NREM) sleep emerges from synchronized activity of widely distributed thalamo-cortical and cortico-cortical networks, reflecting homeostatic and restorative properties of sleep. Slow frequency activity exhibits a reactive nature, and can be increased by acoustic stimulation. Although non-invasive brain stimulation is a promising technique in basic and clinical sleep research, sensory stimulation studies focusing on modalities other than the acoustic are scarce. We explored here the potential of lateralized vibro-tactile stimulation (VTS) of the finger to locally modify electroencephalographic activity during nocturnal NREM sleep. Eight seconds-long sequences of vibro-tactile pulses were delivered at a rate of 1Hz either to the left or to the right index finger, in addition to a sham condition, in fourteen healthy participants. VTS markedly increased slow frequency activity that peaked between 1-4Hz but extended to higher (~13 Hz) frequencies, with fronto-central dominance. Enhanced slow frequency activity was accompanied by increased (14-22 Hz) fast frequency power peaking over central and posterior locations. VTS increased the amplitude of slow waves, especially during the first 3-4s of stimulation. Noticeably, we did not observe local-hemispheric effects, that is, VTS resulted in a global cortical response regardless of stimulation laterality. VTS moderately increased slow and fast frequency activities in resting wakefulness, to a much lower extent compared to NREM sleep. The concomitant increase in slow and fast frequency activities in response to VTS indicates an instant homeostatic response coupled with wake-like, high-frequency activity potentially reflecting transient periods of increased environmental processing.

Placental Location in Women Experienced Cesarean Section using Ultrasonography: A Case-Control Study on Sudanese Women

The objective of this study was to assess the placental location in women with a previous cesarean section (CS) using ultrasonography and the impact of cesarean section (CS) on placenta location. Methods and Results: This case-control study included 205 pregnant women with normal singleton pregnancies (83 women with previous CS [case group] and 122 without previous CS [control group]). The study was conducted at three general hospitals in Khartoum State from August to November 2019. The women were investigated using a Mindary ultrasound machine DP_2200 equipped with 3.5MHz transducers. The anterior placenta location was more prevalent than others: 43.3% and 45.9% for cases and control, respectively. The incidence of placenta previa (PP) and the low-lying placenta (LLP) was 1.2% and 3.6%, respectively, in the case group, and 0.0 and 0.8%, respectively, in the control group. Women with a previous CS were at high risk of the LLP and PP (OR=6.12). Conclusion: Our study concluded that the most common sites of the placenta in women with a previous CS were anterior and posterior locations. The study also concluded that women with a previous history of CS are at high risk for LLP and PP.

Evaluation of the posterior superior alveolar artery location and diameter with a newly defined stable plane

The aim of this study was to analyse the vertical location of the posterior superior alveolar artery (PSAA) using a reliable new reference plane regardless of tooth and alveolar bone, and to measure the diameter in each posterior tooth region, which is of relevance to lateral sinus floor elevation surgery. A total of 270 sinuses in 139 patients were examined in this study. The A-plane was defined by A-point and the bilateral jugal points on reconstructed three-dimensional images. The distance from the PSAA to the defined plane was measured in four regions: first premolar (P1), second premolar (P2), first molar (M1), and second molar (M2). The average distance of the PSAA above the plane in the P1, P2, M1, and M2 regions was determined to be 10.24mm, 7.35mm, 5.47mm, and 7.23mm, respectively. The PSAA was found to run above the plane in 97.4% of sinuses, below the plane in 1.1%, and on the plane in 1.5%. In conclusion, the new plane is useful for intraoperative location of the PSAA. According to the study findings, the area below the reference plane can be considered safe for lateral approach sinus surgery in terms of preserving the integrity of the PSAA.

Evaluating vibrating line location with respect to palatine fovea in various soft palate types

Aim: To determine the frequency of the location of vibrating line in relation to palatine fovea in Class I, II and III soft palate types among patients at Islamic International Dental College, Islamabad. Study design: A cross-sectional observational study Place and duration: Prosthodontic Dept of Islamic International Dental College, Riphah International University, from 2nd October 2021 till 2nd January 2022. Methodology: A total of 200 subjects were selected and clinically examined for various locations of vibrating line with respect to palatine fovea in soft palate types (I, II, III). Phonation method ‘Ah’ was used to locate vibrating line location. Results: The vibrating line location was anterior to palatine fovea in 72.7%, 64.1%, 50% of subjects with Class I, II, III soft palate. 16.5%, 25.6%, 22.7% subjects had vibrating line locating at fovea palatine in Class I, II, III soft palate types. Least observed location was the posterior location of vibrating line; 10.8%,10.3% 27.3% in all soft palate types (class I, II, III). In-significant association with age, gender and soft palate types was seen with location of vibrating line. Conclusion: The vibrating line was located predominantly anterior to palatine fovea in all three soft palate types. Keywords: Dentures, Post dam area, Palatine Fovea, Retention, Soft Palate Contours, Vibrating line.

Pituitary stalk interruption syndrome (PSIS): do not miss this diagnosis

BackgroundPituitary stalk interruption syndrome (PSIS) is one of the rare endocrinal aetiologies of the abnormal short stature. This is a syndrome characterized by a specific tirade, an absent or hypoplastic anterior pituitary gland, thin or absent infundibulum, and ectopic posterior pituitary location. This type of pituitary dwarfism is usually presented in the first decade of life and may be first isolated with normal other pituitary hormones.ResultsOnly 3 out of 117 dwarf patients (2.5%) were found to have pituitary stalk interruption syndrome.ConclusionAlthough of rare incidence, pituitary stalk interruption syndrome (PSIS) is an entity which leads to pituitary dwarfism and should be kept in mind while investigating a child with pituitary dwarfism and radiologists should be aware of its rarely encountered diagnostic MRI findings for early diagnosis and treatment.

Predictors of flow diverter stent in large and giant unruptured intracranial aneurysms, single-center experience

BackgroundFlow diversion with or without coiling has been established as the treatment of choice for large unruptured aneurysms. This study aims to assess possible predictors for radiological and clinical outcome such as location of the aneurysm (anterior or posterior circulation), complexity by a branching artery, bifurcation, and adjuvant coiling.MethodsThis study was conducted on 65 consecutive patients with 65 large, unruptured intracranial aneurysms (size ≥ 10 mm) treated with flow diverters. Follow-up angiography was done for 60 patients (92.3%) at 12 ± 8.6 months range from 3 to 36 months.ResultsComplete occlusion was achieved in 50 from 60 aneurysms (83.4%), while 8 aneurysms (13.3%) had neck remnant, and another two aneurysms (3.3%) remained with aneurysmal remnant. Periprocedural complications were encountered in 14 patients (21.5%) with morbidity in six patients (9.2%) and mortality in one patient (1.5%). In a multivariate logistic regression, anterior versus posterior location was less likely associated with worse outcome; adjusted OR (95% CI) of 0.16 (0.07–0.01), p = 0.006. Complete occlusion in complex aneurysms with branching artery was 60% versus 88% in simple aneurysms without branching artery (p-value = 0.04).ConclusionsFlow diverter deployment of a large, unruptured aneurysm in the anterior circulation might have a better outcome than one in the posterior circulation. Flow diverter of aneurysms with branching artery or at bifurcation might be associated with aneurysm persistence and complications respectively.

Gait ability on center of pressure excursion using a pressure-sensitive mat in the elderly with ischemic stroke: a case–control study with propensity score matching

Background: Center of pressure (COP) is a useful measure for dynamic balance, which directly represents the ability of weight shift and control of the foot, however, there is no study analyzing COP during whole stance phase in the elderly with acute stroke.Methods: A total of 30 acute ischemic stroke patients (mean age±standard deviation [SD], 75.0±5.6 years; 11 females) and 30 propensity score matched controls (mean age±SD, 72.8±5.9 years; 17 females) using age, sex, and Korean version of Mini-Mental State Examination score were finally included. Participants performed barefoot walking trials on a pressure-sensitive mat until 20 footfalls in each limb were corrected. To evaluate gait function based on COP, mean and coefficient of variance as variability were calculated for 3 types of variables as followings: (1) durations of sub-phases in stance phase, (2) mean locations and displacement ranges of COP, and (3) velocities.Results: Significant difference was observed in many of both mean and variability variables. Especially, stroke patients had an increased duration, posterior location of COP, wide range of mediolateral and anteroposterior displacement range, and slow velocity in foot flat phase belonging to the double limb stance. In variability variables, stroke patients had significantly larger variabilities of COP velocities in all sub-phases except in foot flat phase and late propulsive phase were stood out.Conclusions: The elderly with acute ischemic stroke had inefficiency during double limb stance and reduced functional balance in single limb stance in both sides, implying impaired gait ability on COP excursion in these patients.

Imaging of Structural Abnormalities of the Sacrum: The Old Faithful and Newly Emerging Techniques.

The sacrum and sacroiliac joints pose a long-standing challenge for adequate imaging because of their complex anatomical form, oblique orientation, and posterior location in the pelvis, making them subject to superimposition. The sacrum and sacroiliac joints are composed of multiple diverse tissues, further complicating their imaging. Varying imaging techniques are suited to evaluate the sacrum, each with its specific clinical indications, benefits, and drawbacks. New techniques continue to be developed and validated, such as dual-energy computed tomography (CT) and new magnetic resonance imaging (MRI) sequences, for example susceptibility-weighted imaging. Ongoing development of artificial intelligence, such as algorithms allowing reconstruction of MRI-based synthetic CT images, promises even more clinical imaging options.

Misleading Robot Signals in a Classification Task Induce Cognitive Load as Measured by Theta Synchronization Between Frontal and Temporo-parietal Brain Regions.

As technological advances progress, we find ourselves in situations where we need to collaborate with artificial agents (e.g., robots, autonomous machines and virtual agents). For example, autonomous machines will be part of search and rescue missions, space exploration and decision aids during monitoring tasks (e.g., baggage-screening at the airport). Efficient communication in these scenarios would be crucial to interact fluently. While studies examined the positive and engaging effect of social signals (i.e., gaze communication) on human-robot interaction, little is known about the effects of conflicting robot signals on the human actor's cognitive load. Moreover, it is unclear from a social neuroergonomics perspective how different brain regions synchronize or communicate with one another to deal with the cognitive load induced by conflicting signals in social situations with robots. The present study asked if neural oscillations that correlate with conflict processing are observed between brain regions when participants view conflicting robot signals. Participants classified different objects based on their color after a robot (i.e., iCub), presented on a screen, simulated handing over the object to them. The robot proceeded to cue participants (with a head shift) to the correct or incorrect target location. Since prior work has shown that unexpected cues can interfere with oculomotor planning and induces conflict, we expected that conflicting robot social signals which would interfere with the execution of actions. Indeed, we found that conflicting social signals elicited neural correlates of cognitive conflict as measured by mid-brain theta oscillations. More importantly, we found higher coherence values between mid-frontal electrode locations and posterior occipital electrode locations in the theta-frequency band for incongruent vs. congruent cues, which suggests that theta-band synchronization between these two regions allows for communication between cognitive control systems and gaze-related attentional mechanisms. We also find correlations between coherence values and behavioral performance (Reaction Times), which are moderated by the congruency of the robot signal. In sum, the influence of irrelevant social signals during goal-oriented tasks can be indexed by behavioral, neural oscillation and brain connectivity patterns. These data provide insights about a new measure for cognitive load, which can also be used in predicting human interaction with autonomous machines.

Silk Vista Baby flow diverter stent for ruptured intracranial aneurysms: a retrospective observational study.

Flow diversion changed the approach to complex intracranial aneurysms, leading to a widespread use and a rapid technological evolution. Indeed, indications continued to expand, including ruptured intracranial aneurysms in selected cases. Recently, new devices have been designed specifically to target smaller vessels. Therefore, we conducted a multicenter study to evaluate clinical outcome, complications, and occlusion rate of patients with ruptured aneurysms treated with new generation low profile Silk Vista Baby (SVB) flow diverter stent (FD). We performed a retrospective observational study on consecutive patients who underwent treatment with SVB for ruptured aneurysms at 12 Italian centers. Primary end point was favorable clinical outcome rate, defined as modified ranking score (mRS) of 0-2 at the 3months. Secondary outcomes were complication rate, aneurysm re-rupture, and complete aneurysm occlusion at last radiological follow-up. Twenty-five patients were included; at 3months' follow-up, 19 patients (79.1%) had favorable clinical outcome (mRS 0-2). Three patients (12.5%) died during follow-up. In-stent thrombosis occurred in two cases (8.3%), managed with glycoprotein IIb/IIIA and intra-stent angioplasty, without clinical consequences. In 18 (85.7%) patients, complete occlusion at 3months was demonstrated. No rebleeding occurred during follow-up. Presentation with unfavorable World Federation of Neurosurgical Societies grading system (WFNS) and posterior circulation location were both significantly correlated with unfavorable clinical outcome (p = 0.005 and p = 0.02). Our data suggests that low profile FD treatment of ruptured intracranial aneurysms located distally of the circle of Willis is feasible. New generation low profile FD may represent an alternative option in carefully selected cases.