Novel use of a closed-tip stent retriever to prevent distal embolism in the posterior circulation: illustrative case

BACKGROUND

In mechanical thrombectomy for tandem occlusions in vertebrobasilar stroke, distal emboli from the vertebral artery lesion should be prevented. However, no suitable embolic protection devices are currently available in the posterior circulation. Here, the authors describe the case of a vertebral artery lesion effectively treated with a closed-tip stent retriever as an embolic protection device in the posterior circulation.

OBSERVATIONS

A 65-year-old male underwent mechanical thrombectomy for basilar artery occlusion, with tandem occlusion of the proximal vertebral artery. After basilar artery recanalization via the nonoccluded vertebral artery, a subsequent mechanical thrombectomy was performed for the occluded proximal vertebral artery. To prevent distal embolization of the basilar artery, an EmboTrap III stent retriever was deployed as an embolic protection device within the basilar artery to successfully capture the thrombus.

LESSONS

A stent retriever with a closed-tip structure can effectively capture thrombi, making it a suitable distal embolic protection device in the posterior circulation.

Risk of Bone Wax Migration During Retrosigmoid Craniotomy for Microvascular Decompression: Case-Control Study

BACKGROUND AND OBJECTIVES

Bone wax is a flexible hemostatic agent commonly used for surgery in the posterior cranial fossa to control bleeding from the mastoid emissary vein. A large amount of bone wax can migrate into the sigmoid sinus through the mastoid emissary canal (MEC). We aimed to identify clinical factors related to intraoperative bone wax migration through the MEC during microvascular decompression (MVD) surgery, which may result in sigmoid sinus thrombosis.

METHODS

We retrospectively collected the clinical data of patients with trigeminal neuralgia, hemifacial spasm, or trigeminal neuralgia accompanied by painful tic convulsif who underwent MVD. Basic information and the residual width and length (from the bone surface to the sigmoid sinus) of the MEC on computed tomography images were collected. We compared the collected clinical data between 2 groups of cases with and without intraoperative bone wax migration in the sigmoid sinus.

RESULTS

Fifty-four cases with intraoperative bone wax migration and 187 patients without migration were enrolled. The t -test revealed significant differences in the width and length of the MEC ( P = .013 and P = .003, respectively). These variables were identified as significant factors in predicting intraoperative bone wax migration using multivariate logistic regression analysis.

CONCLUSION

The large size of the MEC may be related to intraoperative bone wax migration into the sigmoid sinus in MVD. Neurosurgeons should be aware of these risks. Bone wax should be applied appropriately and hemostasis should be considered to control bleeding from the mastoid emissary vein in patients with a large MEC.

Clinical evaluation of mechanical thrombectomy for patients with posterior circulation occlusion: A retrospective study

OBJECTIVE

Although consensus has been reached regarding the use of mechanical thrombectomy for acute large anterior circulation occlusion, its effectiveness in patients with posterior circulation occlusion remains unclear. This study aimed to establish the determining factors for good clinical outcomes of mechanical thrombectomy for posterior circulation occlusion.

METHODS

We extracted cases of acute large vessel occlusion (LVO) in the posterior circulation from a database comprising 536 patients who underwent mechanical thrombectomy at our hospital between April 2015 and March 2021.

RESULTS

Fifty-two patients who underwent mechanical thrombectomy for LVO in the posterior circulation were identified. Five patients with simultaneous occlusion of the anterior and posterior circulation were excluded; finally, 47 patients were included in this study. The median patient age was 78 years, and 36% of the patients were women. The median National Institutes of Health Stroke Scale (NIHSS) score on admission was 31, the median posterior circulation-Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS) was 8, and the median Basilar Artery on Computed Tomography Angiography (BATMAN) score was 6. The rate of good recanalization (Thrombolysis in Cerebral Infarction scale grades 2b and 3) was 96%, and a good prognosis (modified Rankin Scale score of 0-2 at 90 days) was achieved in 19 patients (40%). The median pc-ASPECTS was significantly higher in the good prognosis group than in the poor prognosis group (10 vs. 7; p = 0.007). The median NIHSS score at presentation was significantly lower in the good prognosis group than in the poor prognosis group (17 vs. 34; p = 0.02). The median BATMAN score was significantly higher in the good prognosis group than in the poor prognosis group (8 vs. 3.5; p = 0.0002). Multivariate analysis showed that an NIHSS score ≦ 20 at presentation was the only independent factor for good prognoses.

CONCLUSION

The prognosis of mechanical thrombectomy for posterior circulation LVO was better in patients with lower NIHSS scores at presentation.

Pipeline embolization device dynamics: prediction of incomplete occlusion by elongation from nominal length

OBJECTIVE

According to benchtop studies, the oversizing of a Pipeline embolization device (PED) relative to the parent artery leads to a significant increase in porosity and potentially compromises aneurysm occlusion as well as transitional zone (TZ) formation around the neck of aneurysms. However, no clinical assessment has been reported. Here this potential was studied by measuring the dynamic changes of PEDs in the clinical time course.

METHODS

The authors retrospectively examined 124 anterior circulation unruptured aneurysms in 114 consecutive patients treated with a PED between July 2015 and December 2020 at their institution. The authors excluded 77 cases of 68 patients with adjunctive coil embolization or multiple stents that could affect the PED dynamics and measurements, and 47 aneurysms in 46 patients were included. Measurements were performed before, immediately after, and 6 months after treatment, and then at intervals of 6 months to 1 year after that for nonocclusion cases.

RESULTS

Complete occlusion was achieved in 79.0% and incomplete occlusion in 21.0% at last follow-up. The PED length immediately after deployment was 136% nominal length. A multivariable regression analysis revealed that age (OR 1.11/year; p = 0.02) and PED elongation from nominal length (OR 1.31/mm; p = 0.012) were independently associated with a higher rate of incomplete occlusion at the last follow-up. TZ formation did not affect the occlusion rate.

CONCLUSIONS

PED elongation from the nominal length is a new predictor of incomplete aneurysm occlusion. The PED showed vascular remodeling by changing its diameter and length in the clinical course. TZ formation was remodeled and did not affect the occlusion rate.

Impact of the lateral skeletal stability following bilateral sagittal split ramus osteotomy for mandibular asymmetry

This study evaluated the stability of bilateral sagittal split ramus osteotomy (BSSRO) associated with positional plagiocephaly and temporal and masseter muscles using posteroanterior cephalogram analysis and three-dimensional computed tomography (3D-CT). This retrospective cohort study included 31 patients who underwent BSSRO for mandibular asymmetry. The cranial vault asymmetry index (CVAI) and the cephalic index were used as indicators of positional plagiocephaly. The distance from the vertical reference line to the menton (Me) was measured on posteroanterior cephalograms immediately and 1 year after surgery, and postoperative stability was assessed. Temporal and masseter muscles were constructed from 3D-CT data and their volumes were measured. Simple regression analysis showed a significant correlation between postoperative changes in the vertical reference line to the Me and the CVAI (R = 0.56, p = 0.001), the amount of surgical movement in the vertical reference line to the Me (R = 0.41, p = 0.023), and the variable temporal muscle volume (R = 0.27, p = 0.028). There was no significant correlation between postoperative changes in the vertical reference line to the Me and the cephalic index (R = 0.093, p = 0.62) and variable masseter muscle volume (R = 0.16, p = 0.38). According to multivariate analysis, CVAI (p = 0.003) and amount of surgical movement in the vertical reference line to the Me (p = 0.014) were significant predictors of postoperative change in the vertical reference line to the Me. Positional plagiocephaly and amount of surgical movement influence lateral skeletal stability following BSSRO for mandibular asymmetry.

Intramedullary feeder aneurysm of a cervical epidural arteriovenous fistula causing myelopathy: a case report and literature review

While a craniocervical junction (CCJ) epidural arteriovenous fistula (EDAVF) may present with hemorrhagic myelopathy from an associated feeder aneurysm on rare occasions, non-hemorrhagic myelopathy from such an aneurysm remains unreported. A woman in her late sixties presented with cervical myelopathy due to a non-hemorrhagic intramedullary aneurysm associated with CCJ-EDAVF. The intramedullary aneurysm originated from the spinal pial artery supplied by the anterior spinal artery. Direct surgical fistula coagulation and feeder obliteration resulted in the disappearance of the aneurysm and myelopathy improvement. This report illustrates the first case of a non-hemorrhagic intramedullary aneurysm associated with CCJ-EDAVF successfully treated with direct surgery.

Functionality and Usability of the Exoscope in Microvascular Decompression for Hemifacial Spasm and Trigeminal Neuralgia

BACKGROUND

Studies on the functionality and usability of the exoscope in neurosurgical procedures against surgical microscopes (SMs) are limited. This study aimed to examine the functionality and usability of the exoscope during microvascular decompression (MVD) surgery.

METHODS

Seven neurosurgeons evaluated the usefulness of a 4 K, 3-dimension digital exoscope in MVD by answering a questionnaire. The questionnaire inquired about the functionality and usability of the exoscope by utilizing a visual analog scale (VAS; 1-10). A score of 5 on VAS was equivalent to the corresponding quality of the SM. The learning effect of the exoscope was evaluated using mean VAS scores in the first and last 3 cases for each neurosurgeon.

RESULTS

The functionality of the exoscope in MVD was superior to that in SM (P < 0.001). In the last 3 surgeries, the mean VAS scores of the exoscope were excellent in terms of ease of arm handling, exchange of surgical instruments, ease of surgical procedure, and intraoperative physical stress. The mean VAS scores of the exoscope in intraoperative asthenopia were significantly higher than those of the SM (P < 0.001). No statistical significance was found in operation time, discharge outcome, and 1-year post-surgery outcome between MVD performed using the exoscope and SM.

CONCLUSIONS

Neurosurgeons may experience reduced stress levels during MVD when using the exoscope. As the outcome of MVD using the exoscope did not demonstrate a statistical difference compared with MVD using the SM, the exoscope may prove to be a useful tool for performing MVD.

Development of a Machine Learning Model to Evaluate Changes during Radiotherapy in Cervical Cancer Tumor Cells

PURPOSE/OBJECTIVE(S)

Radiotherapy is considered the standard treatment for advanced cervical cancer. It is known that irradiation changes the morphology of tumor cells during the treatment, though its clinical significance is unknown. Recently, the usefulness of machine learning using medical images has been reported, as also as pathological images. The purpose of this study is to create a classification model for cervical tumor biopsy treated with radiotherapy, visualized on whole slide images using machine learning, in an attempt to explore the clinical significance of morphology changes during radiotherapy.

MATERIALS/METHODS

Cervical cancer patients who underwent radical irradiation with both pre- and mid-treatment biopsy from April 1, 2013, to December 1, 2020, were retrospectively analyzed. Tumor biopsies were Hematoxylin and eosin stained and digitized to whole slide images (WSIs). WSI s were divided into tiles of 224 × 224 pixels and converted into feature vectors using a pre-trained convolutional neural network (densenet121). A training and test dataset were divided 1:1 on a patient basis, and the model was trained to classify "pre-treatment" and "mid-treatment", and its accuracy was evaluated. The probability obtained from the classification model was defined as the radiation change index (RCI), and its color map was projected on the WSI for visualization. Survival analysis was performed to examine the clinical significance of the RCI values.

RESULTS

A total of eighty-four patients were analyzed, and the median observation period was 3.2 years. 184 WSIs were obtained, and 2203407 tiles were generated. The classification model was trained using 2500 tiles for each "pre-treatment" and "mid-treatment". The accuracy of the classification model was 70.8 %, with an AUC of 0.77 for the ROC curve. The probability obtained from the classification model was defined as RCI, with 0 being "pre-treatment" and 1 being "mid-treatment", and the mean RCI of "pre-treatment" and "mid-treatment" were 0.38 and 0.61, respectively. When the RCIs were visualized with a color map, the areas considered to be "pre-treatment" were consistent with a viable tumor component, and the areas considered to be "mid-treatment" were consistent with fibrosis supposed to cause by irradiation. To evaluate the clinical significance of RCI, we divide the clinical cohort into two groups with a threshold mean RCI of 0.4 in the pre-treatment biopsy. The disease-free survival was 91 months and 47 months in the RCI<0.4 and RCI≥0.4 groups, respectively.

CONCLUSION

We created a model to classify tissues before and during radiotherapy and successfully visualized it on slide images. The low RCI group before treatment had a better prognosis than the high RCI group, suggesting that the tumor morphologic features obtained by machine learning may be useful for prognosis prediction. Further studies are planned to develop a model that can accurately predict prognosis.

Optimization of a fast deuterium diagnostic method based on visible energetic 3He spectroscopy for high electron density plasmas

Fast ions play a crucial role in plasma heating, and their behavior in the plasma must be accurately understood. A diagnostics method based on charge exchange emission from the n = 4 - 3 transition (λ0 = 468.6 nm) of energetic 3He produced by the deuteron-deuteron reaction has been proposed as a for fast deuterons with energies in the order of MeV. The proposed method has the following advantages: No beam emission interferes with the spectra, the direction of the measuring line of sight, and the injection angle of the diagnostic beam can be freely determined. In previous studies, due to competing bremsstrahlung, it was expected that the proposed method will not be practical in the case of high electron density operation. This paper makes the proposed method available for measurement even at high electron densities by optimizing the measurement line of sight direction and the diagnostic beam incidence angle. This allows an electron density five times larger than the range of applications shown in previous studies. This result will contribute to measure of DT alpha in ITER.

Hepatocyte-specific damage in acute toxicity of sodium ferrous citrate: Presentation of a human autopsy case and experimental results in mice

Acute iron overload is known to exert deleterious effects in the liver, but detailed pathology has yet to be documented. Here, we report pathological findings in an autopsy case of acute iron toxicity and validation of the findings in mouse experiments. In a 39-year-old woman who intentionally ingested a large amount of sodium ferrous citrate (equivalent to 7.5 g of iron), severe disturbance of consciousness and fulminant hepatic failure rapidly developed. Liver failure was refractory to treatment and the patient died on Day 13. Autopsy revealed almost complete loss of hepatocytes, while bile ducts were spared. To examine the detailed pathologic processes induced by excessive iron, mice were orally administered equivalent doses of ferrous citrate. Plasma aminotransferase levels markedly increased after 6 h, which was preceded by increased plasma iron levels. Hepatocytes were selectively damaged, with more prominent damage in the periportal area. Phosphorylated c-Jun was detected in hepatocyte nuclei after 3 h, which was followed by the appearance of γ-H2AX expression. Hepatocyte injury in mice was associated with the expression of Myc and p53 after 12 and 24 h, respectively. Even at lethal doses, the bile ducts were morphologically intact and fully viable. Our findings indicate that acute iron overload induces hepatocyte-specific liver injury, most likely through hydroxyl radical-mediated DNA damage and subsequent stress responses.

First-in-human trial of Center Wire for neuroendovascular therapy to avoid guidewire-related complications

BACKGROUND

An exchange maneuver is useful for the delivery of devices to target vessels. However, hemorrhagic complications can occur due to vessel perforation during an exchange maneuver. In addition, the exchange is often challenging due to unfavorable anatomy. Center Wire is an exchange-length wire with a nondetachable stent that was developed to improve navigation and stability during exchange maneuvers. The aim of this study is to investigate the safety and efficacy of Center Wire of the anchor wire technique during neuroendovascular treatment.

METHODS

Ten patients with intracranial aneurysms were treated after signing a Certified Review Board-approved consent. Anchor wire technique was used in all patients to navigate catheters to the target vessel for aneurysm treatment.

RESULTS

Anchor wire technique was successfully applied in all 10 cases using Center Wire. One device-related incident of vasospasm occurred which was asymptomatic. No device-related dissection, perforation, or thromboembolic events occurred. One patient had intraoperative aneurysm rupture during coil placement which was treated immediately without clinical consequences. Two patients had postoperative ischemic strokes due to thrombotic occlusion of branches originating from the aneurysm which were unrelated to the device.

CONCLUSIONS

This first-in-human trial of Center Wire demonstrated the safety and efficacy of the anchor wire technique for neuroendovascular treatment in a strictly regulated prospective registry trial.

Detection of CpG methylation level using methyl-CpG-binding domain-fused fluorescent protein

Methylation of cytosine to 5-methylcytosine on CpG dinucleotides is the most frequently studied epigenetic modification involved in the regulation of gene expression. In normal tissues, tissue-specific CpG methylation patterns are established during development. In contrast, alterations in methylation patterns have been observed in abnormal cells, such as cancer cells. Cancer type-specific CpG methylation patterns have been identified and used as biomarkers for cancer diagnosis. In this study, we developed a hybridization-based CpG methylation level sensing system using a methyl-CpG-binding domain (MBD)-fused fluorescent protein. In this system, the target DNA is captured by a complementary methylated probe DNA. When the target DNA is methylated, a symmetrically methylated CpG is formed in the double-stranded DNA. MBD specifically recognizes symmetrical methyl-CpG on double-stranded DNA; therefore, the methylation level is quantified by measuring the fluorescence intensity of the bound MBD-fused fluorescent protein. We prepared MBD-fused AcGFP1 and quantified the CpG methylation levels of the target DNA against SEPT9, BRCA1, and long interspersed nuclear element-1 (LINE-1) using MBD-AcGFP1. This detection principle can be applied to the simultaneous and genome-wide modified base detection systems using microarrays coupled with modified base binding proteins fused to fluorescent proteins.

Cone-beam CT-assisted microcatheter tip placement at the shunted pouch entry zone: A technical note for anterior condylar arteriovenous fistula

Accurate microcatheter placement for anterior condylar arteriovenous fistula (AVF) enables selective transvenous embolization (TVE) and helps to avoid hypoglossal nerve palsy. Anterior condylar AVF has a shunted pouch within the condylar vascular and osseous structures. Detailed anatomical comprehension of the shunted pouch is essential, in addition, we believe that it is important to have a strategy for where in the shunted pouch to start filling with coils. Specifically, we consider that it is important to structurally understand the more upstream location (arterial side) within the shunted pouch (called "shunted pouch entry zone"), guide the microcatheter there, and embolize from that site. Although several studies have discussed the usefulness of intraoperative cone-beam computed tomography (CBCT) for treating anterior condylar AVF, there are no studies which have mentioned the importance of microcatheter position before coil embolization in selective TVE as in this study. Intraoperative localization of the shunted pouch entry zone is often difficult. Herein, the authors report that cone-beam computed tomography (CBCT) can assist accurate microcatheter tip placement at the shunted pouch entry zone before staring embolization. This is the novel application of intraoperative CBCT to treat anterior condylar AVF successfully treated with precise and selective TVE.

First-in-human trial of Stabilizer device in neuroendovascular therapy

Objectives

Flow diverter or stent implantation to intracranial target lesion requires large inner diameter microcatheter navigation. The exchange method using stiff long wire is often necessary if it is difficult to navigate over the regular guidewire. However, this method has an intrinsic risk of vessel damage and may cause severe complications. We investigated the safety and efficacy of a new device, the Stabilizer device for navigation in a first-in-human clinical trial under the Certified Review Board agreement.

Materials and methods

The Stabilizer is a 320 cm length exchange wire with a stent for anchoring and is compatible with a 0.0165" microcatheter. The trial design is a prospective single-arm open-label registry. Inclusion criteria are elective flow diverter treatment or stent-assisted coiling, expected to be difficult to navigate a microcatheter with a regular micro guidewire, and obtained documented consent. The primary endpoint of the study was a hemorrhagic complication.

Results

Five patients were enrolled in this trial. The median age is 52 years, ranges from 41 to 70, and all patients were female. Three aneurysms were located on the internal carotid artery, one on the vertebral artery, and one on the basilar artery. Basilar artery aneurysm was treated by stent-assisted coiling and others were treated by flow diverter deployment. All cases successfully navigate microcatheter for the treatment by the trial method using Stabilizer device without any adverse event.

Conclusions

The results from this first-in-human consecutive five cases show the safety of the Stabilizer device in neuro-endovascular therapy for navigation of devices to the intracranial target lesion.

Enhanced Material Assimilation in a Toroidal Plasma Using Mixed H_{2}+Ne Pellet Injection and Implications to ITER

The ablation and assimilation of cryogenic pure H_{2} and mixed H_{2}+Ne pellets, which are foreseen to be used by the ITER tokamak for mitigating thermal and electromagnetic loads of major disruptions, are observed by spatially and temporally resolved measurements. It is experimentally demonstrated that a small fraction (here ≈5%) of neon added to hydrogenic pellets enhances the core density assimilation with reduced outward transport for the low magnetic-field side injection. This is consistent with theoretical expectations that line radiation increased by doped neon in dense plasmoids suppresses the plasmoid pressure and reduces the E[over →]×B[over →] transport of the ablated material.

Intraosseous carcinoma of the anterior maxilla identified as the occult primary tumour of carcinoma of unknown primary

Carcinoma of unknown primary (CUP) is defined as lymph node metastasis without a detectable origin until after the initial treatment has been performed. The most common occult primary site in the head and neck, as revealed by a review of the published literature, is the oropharynx. An occult primary site in the oral region is extremely rare. We report a rare case of head and neck CUP (HNCUP) in a 69-year-old female patient, wherein the occult primary lesion was a primary intraosseous carcinoma (PIOC) invading the anterior maxilla. During the course of the initial diagnostic workup, no primary lesion could be identified; however, cervical lymph node metastasis to left levels IB and IIA were observed in the patient. A neck dissection followed by adjuvant radiotherapy was performed. However, the PIOC of the anterior maxilla was identified 6 months after neck treatment and was confirmed as the occult primary tumour of the HNCUP. This case is quite rare and required a comprehensive workup to guide optimal treatment. Careful follow-up or active biopsy should be considered if osteolytic changes are observed in the jaw.

Predicting the growth of middle cerebral artery bifurcation aneurysms using differences in the bifurcation angle and inflow coefficient

OBJECTIVE

Growing intracranial aneurysms (IAs) are prone to rupture. Previous cross-sectional studies using postrupture morphology have shown the morphological or hemodynamic features related to IA rupture. Yet, which morphological or hemodynamic differences of the prerupture status can predict the growth and rupture of smaller IAs remains unknown. The purpose of this longitudinal study was to investigate the effects of morphological features and the hemodynamic environment on the growth of IAs at middle cerebral artery (MCA) bifurcations during the follow-up period.

METHODS

One hundred two patients with MCA M1–2 bifurcation saccular IAs who underwent follow-up for more than 2 years at the authors’ institutions between 2011 and 2019 were retrospectively identified. During the follow-up period, cases involving growth of MCA IAs were assigned to the event group, and those with MCA IAs unchanged in size were assigned to the control group. The morphological parameters examined were aneurysmal neck length, dome height, aspect ratio and volume, M1 and M2 diameters and their ratio, and angle configurations among M1, M2, and the aneurysm. Hemodynamic parameters were flow rate and wall shear stress in M1, M2, and the aneurysm, including the aneurysmal inflow rate coefficient (AIRC), defined as the ratio of the aneurysmal inflow rate to the M1 flow rate. Those parameters were compared statistically between the two groups. Correlations between morphological and hemodynamic parameters were also examined.

RESULTS

Eighty-three of 102 patients were included: 25 with growing MCA IAs (event group) and 58 with stable MCA IAs (control group). The median patient age at initial diagnosis was 66.9 (IQR 59.8–72.3) years. The median follow-up period was 48.5 (IQR 36.5–65.6) months. Both patient age and the AIRC were significant independent predictors of the growth of MCA IAs. Moreover, the AIRC was strongly correlated with sharper bifurcation and inflow angles, as well as wider inclination angles between the M1 and M2 arteries.

CONCLUSIONS

The AIRC was a significant independent predictor of the growth of MCA IAs. Sharper bifurcation and inflow angles and wider inclination angles between the M1 and M2 arteries were correlated with the AIRC. MCA IAs with such a bifurcation configuration are more prone to grow and rupture.

Infratentorial developmental venous anomaly concurrent with a cavernoma and dural arteriovenous fistula

OBJECTIVES

While developmental venous anomaly (DVA) may be associated with cavernous malformation, mixed vascular malformation associated with dural arteriovenous fistula (dAVF) has not been previously reported. We observed a case with rare association of infratentorial DVA, cavernous malformation, and dAVF that presented with cerebellar ataxia. We report our endovascular treatment for this complex cerebrovascular condition.

CASE PRESENTATION

A 32-year-old woman with ataxia had an infratentorial DVA associated with a cavernoma and dAVF. The dAVF had two shunting points. The dAVF was fed by the posterior meningeal arteries and drained through the sigmoid sinus into the transverse sinus. The dAVF was also fed by the occipital artery and retrogradely drained through the left jugular bulb into the dilated collecting vein of the DVA. Endovascular embolization was performed for the dAVF and dilated collecting vein of the DVA. Postoperative complications did not occur after embolization with no recurrence for three years.

CONCLUSIONS

This is the first reported case of infratentorial DVA associated with a cavernoma and dAVF. Endovascular treatment was effective in treating this symptomatic complex cerebrovascular disorder.

Deep modeling of plasma and neutral fluctuations from gas puff turbulence imaging

The role of turbulence in setting boundary plasma conditions is presently a key uncertainty in projecting to fusion energy reactors. To robustly diagnose edge turbulence, we develop and demonstrate a technique to translate brightness measurements of HeI line radiation into local plasma fluctuations via a novel integrated deep learning framework that combines neutral transport physics and collisional radiative theory for the 3³D - 2³P transition in atomic helium with unbounded correlation constraints between the electron density and temperature. The tenets for experimental validity are reviewed, illustrating that this turbulence analysis for ionized gases is transferable to both magnetized and unmagnetized environments with arbitrary geometries. Based on fast camera data on the Alcator C-Mod tokamak, we present the first two-dimensional time-dependent experimental measurements of the turbulent electron density, electron temperature, and neutral density, revealing shadowing effects in a fusion plasma using a single spectral line.

Na+/K+ ATPase α1 and β3 subunits are localized to the basolateral membrane of trophectoderm cells in human blastocysts

STUDY QUESTION

Is there a relation between specific Na+/K+ ATPase isoform expression and localization in human blastocysts and the developmental behavior of the embryo?

SUMMARY ANSWER

Na+/K+ ATPase α1, β1 and β3 are the main isoforms expressed in human blastocysts and no association was found between the expression level of their respective mRNAs and the rate of blastocyst expansion.

WHAT IS KNOWN ALREADY

In mouse embryos, Na+/K+ ATPase α1 and β1 are expressed in the basolateral membrane of trophectoderm (TE) cells and are believed to be involved in blastocoel formation (cavitation).

STUDY DESIGN, SIZE, DURATION

A total of 20 surplus embryos from 11 patients who underwent IVF and embryo transfer at a university hospital between 2009 and 2018 were analyzed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

After freezing and thawing Day 5 human blastocysts, their developmental behavior was observed for 24 h using time-lapse imaging, and the expression of Na+/K+ ATPase isoforms was examined using quantitative RT-PCR (RT-qPCR). The expressed isoforms were then localized in blastocysts using fluorescent immunostaining.

MAIN RESULTS AND THE ROLE OF CHANCE

RT-qPCR results demonstrated the expression of Na+/K+ ATPase α1, β1 and β3 isoforms in human blastocysts. Isoforms α1 and β3 were localized to the basolateral membrane of TE cells, and β1 was localized between TE cells. A high level of β3 mRNA expression correlated with easier hatching (P = 0.0261).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The expression of mRNA and the localization of proteins of interest were verified, but we have not been able to perform functional analysis.

WIDER IMPLICATIONS OF THE FINDINGS

Of the various Na+/K+ ATPase isoforms, expression levels of the α1, β1 and β3 mRNAs were clearly higher than other isoforms in human blastocysts. Since α1 and β3 were localized to the basolateral membrane via fluorescent immunostaining, we believe that these subunits contribute to the dilation of the blastocoel. The β1 isoform is localized between TE cells and may be involved in tight junction formation, as previously reported in mouse embryos.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the JSPS KAKENHI (https://www.jsps.go.jp/english/index.html), grant number 17K11215. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have no conflicts of interest.

The bifurcation angle is associated with the progression of saccular aneurysms

The role of the bifurcation angle in progression of saccular intracranial aneurysms (sIAs) has been undetermined. We, therefore, assessed the association of bifurcation angles with aneurysm progression using a bifurcation-type aneurysm model in rats and anterior communicating artery aneurysms in a multicenter case–control study. Aneurysm progression was defined as growth by ≥ 1 mm or rupture during observation, and controls as progression-free for 30 days in rats and ≥ 36 months in humans. In the rat model, baseline bifurcation angles were significantly wider in progressive aneurysms than in stable ones. In the case–control study, 27 and 65 patients were enrolled in the progression and control groups. Inter-observer agreement for the presence or absence of the growth was excellent (κ coefficient, 0.82; 95% CI, 0.61–1.0). Multivariate logistic regression analysis showed that wider baseline bifurcation angles were significantly associated with subsequent progressions. The odds ratio for the progression of the second (145°–179°) or third (180°–274°) tertiles compared to the first tertile (46°–143°) were 5.5 (95% CI, 1.3–35). Besides, the bifurcation angle was positively correlated with the size of aneurysms (Spearman’s rho, 0.39; P = 0.00014). The present study suggests the usefulness of the bifurcation angle for predicting the progression of sIAs.

Pipeline flow diversion with adjunctive coil embolization for internal carotid artery aneurysms following an intradural component: results in 46 consecutive aneurysms from a Japanese single-center experience

In the treatment of an intracranial aneurysm with the flow diverter, the combined use of coil embolization can help promote subsequent progressive thrombosis within the aneurysm sac and reduce the risk of delayed aneurysm rupture. This study retrospectively reviewed outcomes of patients who had undergone the Pipeline Embolization Device (PED) with adjunctive coil embolization (PED/coil) at a single center to determine its safety and efficiency. Patients with internal carotid artery aneurysms following an intradural component were selected for PED/coil between 2015 and 2020. All patients were premedicated with dual antiplatelet therapy of aspirin plus clopidogrel or prasugrel. A minimal number of PEDs were deployed, with coils inserted using a stent-jail technique, avoiding dense packing. A total of 46 aneurysms (43 patients; median dome size, 11.6 mm; median neck width, 6.3 mm) were treated with PED/coil. The median volume embolization ratio was 14.8%. The degree of angiographic filling at the 6-month and latest angiography showed complete occlusion in 60.5% (26/43) and 70.5% (31/44), respectively. Small (< 10 mm) aneurysms achieved a higher complete occlusion rate in the early period; a lower cumulative incidence of aneurysm occlusion was observed in large and giant (≥ 10 mm) aneurysms (P = .024). The median clinical follow-up was 22 months, and no aneurysm ruptures occurred. Favorable clinical outcomes were achieved, with permanent neurological morbidity of 4.7% and no mortality. PED/coil demonstrated a high angiographic occlusion rate at an early stage. Loosely packed coils are sufficient to obliterate aneurysms effectively.

Lyotropic liquid crystal-based transcutaneous peptide delivery system: Evaluation of skin permeability and potential for transcutaneous vaccination

Transcutaneous drug delivery is a promising method in terms of drug repositioning and reformulation because of its non-invasive and easy-to-use features. To overcome the skin barrier, which is the biggest challenge in transcutaneous drug delivery, a number of techniques, such as microemulsion, solid-in-oil dispersions and liposomes, have been studied extensively. However, the low viscosity of these formulations limits drug retention on the skin and reduces patient acceptability. Although viscosity can be increased by adding a thickening reagent, such an addition often alters formulation nanostructures and drug solubility, and importantly, decreases skin permeability. In this study, a gel-like lyotropic liquid crystal (LLC) was used as a tool to enhance skin permeability. In particular, we prepared 1-monolinolein (ML)-based LLCs with different water contents. All LLCs significantly enhanced skin permeation of a peptide drug, an epitope peptide of melanoma, despite their high viscoelasticity. Fourier transform infra-red spectroscopic analysis of the skin surface treated with the LLCs revealed that the gyroid geometry more strongly interacted with the lamellar structure inside the stratum corneum (SC) than the diamond geometry. Finally, as the result of the in vivo tumor challenge experiment using B16F10 melanoma-bearing mice, the LLC with the gyroid geometry showed stronger vaccine effect against tumor than a subcutaneous injection. Collectively, ML-based LLCs, especially with the gyroid geometry, are a promising strategy to deliver biomacromolecules into skin. STATEMENT OF SIGNIFICANCE: Transcutaneous drug delivery is a promising method for drug repositioning and reformulation because of its non-invasive and easy-to-use features. To overcome the skin barrier, which is the biggest challenge in transcutaneous drug delivery, we used a gel-like lyotropic liquid crystal (LLC) as a novel tool to enhance skin permeability. In this paper, we demonstrated that an LLC with a specific liquid crystalline structure has the highest skin permeation enhancement effect for a peptide antigen as a model drug. Moreover, the peptide antigen-loaded LLC showed a vaccine effect that was comparable to a subcutaneous injection in vivo. This study provides a basis for designing a transcutaneous delivery system of peptide drugs with LLC.

Clinical Impact of Large Vessel Occlusion Achieved First Pass Effect with Stent Retriever Alone: A Single-Center Retrospective Analysis

Objective

The first pass effect (FPE), which means the achievement of complete or near-complete reperfusion of large vessel occlusion (LVO) in the first pass, is one of the goals of mechanical thrombectomy (MT). However, the impact of FPE on the prognosis has not been assessed for Japanese patients with various degrees of independence before the onset of LVO. The purpose of this study was to investigate the prognostic effects of FPE in a comprehensive stroke center in Japan, which includes patients in a variety of self-independence states with different comorbidities before stroke onset.

Methods

Between April 2017 and March 2020, 151 patients who underwent MT with a stent retriever (SR) alone as initial strategy for anterior circulation (internal carotid artery terminal, M1, M2) LVO at our hospital and finally achieved modified treatment in cerebral infarction (mTICI) 2b-3 were analyzed. Forty-eight patients in whom first pass mTICI 2c-3 was achieved were classified into the FPE+ group, and the other 103 patients were classified into the FPE- group. We compared the characteristics and clinical outcomes between patients with and without FPE, and estimated the odds ratio for outcomes after adjusting for confounders.

Results

The puncture-reperfusion time was shorter (20 vs. 35 minutes; p <0.01), and cardiogenic embolism was more common (81.3 vs. 60.2%; p = 0.01) in the FPE+ group. The FPE was significantly associated with good neurological outcome after 3 months (p <0.01; adjusted odds ratio [aOR], 3.87; 95% confidence interval [CI], 1.69-9.38), reduction in all intracranial hemorrhage (p <0.01; aOR, 0.24; 95% CI, 0.10-0.54), and symptomatic intracranial hemorrhage (p = 0.04; aOR, 0.16; 95% CI, 0.01-0.98).

Conclusion

The FPE with an SR alone improved the neurological prognosis in a Japanese patient group.

Behçet's Disease with Extremely High Levels of Urinary β2-Microglobulin after Non-Steroidal Anti-Inflammatory Drug Treatment

Behçet's disease is an inflammatory disease which manifests itself as various symptoms, such as uveitis, oral and genital aphthae, erythema nodosa, gastro-intestinal ulcerations and encephalopathy. Among the manifestations, renal dysfunction is reported in some percentage of the patients with this disorder. We experienced a middle-aged male with Behçet's disease who showed an extremely high level of urinary β2-microglulin, which is one of the markers of renal dysfunction, despite normal serum creatinine levels. The patient was on non-steroidal anti-inflammatory drug (NSAID) therapy for 7 weeks, and this could have affected his renal dysfunction. The present report suggests that renal injury should not be underestimated in patients with Behçet's disease, especially in patients using NSAIDs.

Gastrointestinal stromal tumour lacking mutations in the KIT and PDGFRA genes in a cat

Molecular subtyping in gastrointestinal stromal tumours is a useful method for predicting the efficacy of treatment using tyrosine kinase inhibitors in humans. However, owing to the paucity of reports on mutational analyses, the association between genetic mutations and the therapeutic response to tyrosine kinase inhibitors remains unclear in feline gastrointestinal stromal tumours. In this report, we describe the case of a cat with a gastrointestinal stromal tumour which was unresponsive to tyrosine kinase inhibitors. A mutational analysis revealed that the cat lacked mutations in both the KIT and platelet-derived growth factor receptor-alpha (PDGFRA) genes. Our findings are consistent with the fact that KIT/PDGFRA wild-type gastrointestinal stromal tumours are less responsive to tyrosine kinase inhibitors in humans. This signifies the need for further evaluation and possibly individualised treatment for gastrointestinal stromal tumours in cats on the basis of mutational analyses.

Generation of combined hepatocellular-cholangiocarcinoma through transdifferentiation and dedifferentiation in p53-knockout mice

The two principal histological types of primary liver cancers, hepatocellular carcinoma (HCC) and cholangiocarcinoma, can coexist within a tumor, comprising combined hepatocellular‐cholangiocarcinoma (cHCC‐CCA). Although the possible involvement of liver stem/progenitor cells has been proposed for the pathogenesis of cHCC‐CCA, the cells might originate from transformed hepatocytes that undergo ductular transdifferentiation or dedifferentiation. We previously demonstrated that concomitant introduction of mutant HRAS^V12 (HRAS) and Myc into mouse hepatocytes induced dedifferentiated tumors that expressed fetal/neonatal liver genes and proteins. Here, we examine whether the phenotype of HRAS‐ or HRAS/Myc‐induced tumors might be affected by the disruption of the Trp53 gene, which has been shown to induce biliary differentiation in mouse liver tumors. Hepatocyte‐derived liver tumors were induced in heterozygous and homozygous p53‐knockout (KO) mice by hydrodynamic tail vein injection of HRAS‐ or Myc‐containing transposon cassette plasmids, which were modified by deleting loxP sites, with a transposase‐expressing plasmid. The HRAS‐induced and HRAS/Myc‐induced tumors in the wild‐type mice demonstrated histological features of HCC, whereas the phenotype of the tumors generated in the p53‐KO mice was consistent with cHCC‐CCA. The expression of fetal/neonatal liver proteins, including delta‐like 1, was detected in the HRAS/Myc‐induced but not in the HRAS‐induced cHCC‐CCA tissues. The dedifferentiation in the HRAS/Myc‐induced tumors was more marked in the homozygous p53‐KO mice than in the heterozygous p53‐KO mice and was associated with activation of Myc and YAP and suppression of ERK phosphorylation. Our results suggest that the loss of p53 promotes ductular differentiation of hepatocyte‐derived tumor cells through either transdifferentiation or Myc‐mediated dedifferentiation.

Decreased Portal Circulation Augments Fibrosis and Ductular Reaction in Nonalcoholic Fatty Liver Disease in Mice

Nonalcoholic fatty liver disease often progresses to cirrhosis and causes liver cancer, but mechanisms of its progression are yet to be elucidated. Although nonalcoholic fatty liver disease is often associated with abnormal portal circulation, there have not been any experimental studies to test its pathogenic role. Here, whether decreased portal circulation affected the pathology of nonalcoholic steatohepatitis (NASH) was examined using congenital portosystemic shunt (PSS) in C57BL/6J mice. Whereas PSS significantly attenuated free radical-mediated carbon tetrachloride injury, it augmented pericellular fibrosis in the centrilobular area induced by a 0.1% methionine choline-deficient l-amino acid-defined high-fat diet (CDAHFD). PSS aggravated ductular reaction and increased the expression of connective tissue growth factor. Pimonidazole immunohistochemistry of the liver revealed that the centrilobular area of PSS-harboring mice was more hypoxic than that of control mice. Although tissue hypoxia was observed in the fibrotic area in CDAHFD-induced NASH in both control and PSS-harboring mice, it was more profound in the latter, which was associated with higher carbonic anhydrase 9 and vascular endothelial growth factor expression and neovascularization in the fibrotic area. Furthermore, partial ligation of the portal vein also augmented pericellular fibrosis and ductular reaction induced by a CDAHFD. These results demonstrate that decreased portal circulation, which induces hypoxia due to disrupted intralobular perfusion, is an important aggravating factor of liver fibrosis in NASH.

Hepatocyte Mitogen-Activated Protein Kinase Kinase 7 Contributes to Restoration of the Liver Parenchyma Following Injury in Mice

BACKGROUND AND AIMS

Mitogen-activated protein kinase kinase (MKK) 7 and MKK4 are upstream activators of c-Jun NH₂ -terminal kinases (JNKs) and have been shown to be required for the early development of the liver. Although it has been suggested that MKK7 might be involved in the regulation of hepatocyte proliferation, the functional role of MKK7 in the liver has remained unclear.

APPROACH AND RESULTS

Here, we examined phenotypic alterations in liver-specific or hepatocyte/hematopoietic cell-specific MKK7 knockout (KO) mice, which were generated by crossing MKK7^LoxP/LoxP with albumin-cyclization recombination (Alb-Cre) or myxovirus resistance protein 1-Cre mice, respectively. The livers of Alb-Cre^-/+ MKK7^LoxP/LoxP mice developed without discernible tissue disorganization. MKK7 KO mice responded normally to liver injuries incurred by partial hepatectomy or injection of CCl₄ . However, tissue repair following CCl₄ -induced injury was delayed in MKK7 KO mice compared with that of control mice. Furthermore, after repeated injections of CCl₄ for 8 weeks, the liver in MKK7 KO mice showed intense fibrosis with increased protractive hepatocyte proliferation, suggesting that MKK7 deficiency might affect regenerative responses of hepatocytes in the altered tissue microenvironment. MKK7 KO hepatocytes demonstrated normal proliferative activity when cultured in monolayers. However, MKK7 KO significantly suppressed branching morphogenesis of hepatocyte aggregates within a collagen gel matrix. Microarray analyses revealed that suppression of branching morphogenesis in MKK7 KO hepatocytes was associated with a reduction in mRNA expression of transgelin, glioma pathogenesis related 2, and plasminogen activator urokinase-type (Plau); and forced expression of these genes in MKK7 KO hepatocytes partially recovered the attenuated morphogenesis. Furthermore, hepatocyte-specific overexpression of Plau rescued the impaired tissue repair of MKK7 KO mice following CCl₄ -induced injury.

CONCLUSIONS

MKK7 is dispensable for the regenerative proliferation of hepatocytes but plays important roles in repair processes following parenchymal destruction, possibly through modulation of hepatocyte-extracellular matrix interactions.

Fast deuteron diagnostics using visible light spectra of 3He produced by deuteron-deuteron reaction in deuterium plasmas

The fast deuteron (non-Maxwellian component) diagnostic method, which is based on the higher resolution optical spectroscopic measurement, has been developed as a powerful tool. Owing to a decrease in the D-H charge-exchange cross section, the diagnostic ability of conventional optical diagnostic methods should be improved for ∼MeV energy deuterons. Because the ³He-H charge-exchange cross section is much larger than that of D-H in the ∼MeV energy range, the visible light (VIS) spectrum of ³He produced by the dueteron-dueteron (DD) reaction may be a useful tool. Although the density of ³He is small because it is produced via the DD reaction, improvement of the emissivity of the VIS spectrum of ³He can be expected by using a high-energy beam. We evaluate the VIS spectrum of ³He for the cases when a fast deuteron tail is formed and not formed in the ITER-like beam injected deuterium plasma. Even when the beam energy is in the MeV energy range, a large change appears in the half width at half maximum of the VIS spectrum. The emissivity of the VIS spectrum of ³He and the emissivity of bremsstrahlung are compared, and the measurable VIS spectrum is obtained. It is shown that the VIS spectrum of ³He is a useful tool for the MeV beam deuteron tail diagnostics.

Neck Location on the Outer Convexity is a Predictor of Incomplete Occlusion in Treatment with the Pipeline Embolization Device: Clinical and Angiographic Outcomes

BACKGROUND AND PURPOSE

With the increasing use of the Pipeline Embolization Device for the treatment of aneurysms, predictors of clinical and angiographic outcomes are needed. This study aimed to identify predictors of incomplete occlusion at last angiographic follow-up.

MATERIALS AND METHODS

In our retrospective, single-center cohort study, 105 ICA aneurysms in 89 subjects were treated with Pipeline Embolization Devices. Patients were followed per standardized protocol. Clinical and angiographic outcomes were analyzed. We introduced a new morphologic classification based on the included angle of the parent artery against the neck location: outer convexity type (included angle,  <160°), inner convexity type (included angle,  >200°), and lateral wall type (160° ≤ included angle  ≤200°). This classification reflects the metal coverage rate and flow dynamics.

RESULTS

Imaging data were acquired in 95.3% of aneurysms persistent at 6 months. Complete occlusion was achieved in 70.5%, and incomplete occlusion, in 29.5% at last follow-up. Multivariable regression analysis revealed that 60 years of age or older (OR, 5.70; P = .001), aneurysms with the branching artery from the dome (OR, 10.56; P = .002), fusiform aneurysms (OR, 10.2; P = .009), and outer convexity-type saccular aneurysms (versus inner convexity type: OR, 30.3; P < .001; versus lateral wall type: OR, 9.71; P = .001) were independently associated with a higher rate of incomplete occlusion at the last follow-up. No permanent neurologic deficits or rupture were observed in the follow-up period.

CONCLUSIONS

The aneurysm neck located on the outer convexity is a new, incomplete occlusion predictor, joining older age, fusiform aneurysms, and aneurysms with the branching artery from the dome. No permanent neurologic deficits or rupture was observed in the follow-up, even with incomplete occlusion.

REACTOR PHYSICS EXPERIMENT IN A GRAPHITE-MODERATION SYSTEM FOR HTGR

The Japan Atomic Energy Agency (JAEA) started the Research and Development (R&D) to improve nuclear prediction techniques for High Temperature Gas-cooled Reactors (HTGRs). The objectives are to introduce a generalized bias factor method to avoid full mock-up experiment for the first commercial HTGR and to introduce reactor noise analysis to High Temperature Engineering Test Reactor (HTTR) experiment to observe sub-criticality. To achieve the objectives, the reactor core of graphite-moderation system named B7/4”G2/8”p8EUNU+3/8”p38EU(1) was newly composed in the B-rack of Kyoto University Critical Assembly (KUCA). The core is composed of the fuel assembly, driver fuel assembly, graphite reflector, and polyethylene reflector. The fuel assembly is composed of enriched uranium plate, natural uranium plate and graphite plates to realize the average fuel enrichment of HTTR and it’s spectrum. However, driver fuel assembly is necessary to achieve the criticality with the small-sized core. The core plays a role of the reference core of the bias factor method, and the reactor noise was measured to develop the noise analysis scheme. In this study, the overview of the criticality experiments is reported. The reactor configuration with graphite moderation system is rare case in the KUCA experiments, and this experiment is expected to contribute not only for an HTGR development but also for other types of a reactor in the graphite moderation system such as a molten salt reactor development.

SAT0208 INCIDENCES OF ADVERSE EFFECTS AND DISEASE FLARE DUE TO PNEUMOCYSTIS PNEUMONIA PROPHYLAXIS WITH TRIMETHOPRIM/SULFAMETHOXAZOLE IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS

Background:

Methods of preventing pneumocystis pneumonia (PCP) in systemic lupus erythematosus (SLE) are controversial. Previous studies have verified the efficacy and safety of trimethoprim/sulfamethoxazole (TMP-SMX) in patients with rheumatic diseases1. However, as for SLE, some clinicians advise against prescribing TMP-SMX because sulfa allergy is reportedly more common in SLE than in other rheumatic diseases2, 3. Anecdotally, sulfonamides may also worsen SLE itself, but few data are available on lupus flares related to sulfonamides3.

Objectives:

This study aimed to assess the incidences of adverse effects and disease flare due to PCP prophylaxis with TMP-SMX in SLE patients.

Methods:

SLE patients seen at our hospital between September 2010 and April 2018 who received TMP-SMX as a PCP prophylaxis were enrolled. The clinical manifestations, treatment course, adverse drug reactions, and occurrence of lupus flares were retrospectively assessed from the medical records. The Naranjo adverse drug reaction probability scale4 was used to determine whether the reactions were induced by SMX-TMP. According to the British Isles Lupus Assessment Group (BILAG) 2004 index, a severe flare of lupus was defined as a development of a new grade A manifestation, and a moderate flare as a development of grade B manifestation following grade C, D or E. Two board-certificated rheumatologists reviewed the medical records in a blinded fashion to determine the reason for the flare, with disagreement resolved by consensus.

Results:

In total, 188 SLE patients were enrolled; of these, 117 (62.2%) had no adverse events and were able to continue taking SMX-TMP as needed. Seventy-one patients (37.8%) stopped SMX-TMP due to suspected adverse drug reactions, including fever, rash, liver function disorder, and cytopenia. The Naranjo scale indicated “definite” in 4, “probable” in 39, and “possible” in 28. Eighteen-patients restarted the SMX-TMP and 9 patients could continue the prophylaxis without adverse effects. Five patients were hospitalized to treat the adverse events: 3 with drug rash (concomitant use of hydroxychloroquine in 2), 1 with hypersensitivity (concomitant use of azathioprine) and 1 with hyponatremia, respectively.

Lupus flares occurred in 10 patients (5.3%) within one month after the start of the the SMX-TMP prophylaxis. Macrophage activation syndrome (MAS) or neuropsychiatric SLE occurred in 9 of them. Of 188 cases, 2 patients (1.1%) developed a new onset of MAS during the stable clinical course as the flare, which was considered due to SMX-TMP. Confounding factors, including high disease activity and the reduction of glucocorticoids, were identified in other 8 flares.

Conclusion:

PCP prophylaxis with SMX-TMP was tolerable in most SLE patients. However, a small number of SLE patients developed severe adverse effects or disease flares due to the SMX-TMP.

References:

[1]Park JW, et al. Annals of the Rheumatic Diseases 2018;77:644-649.

[2]Suyama Y, et al. Modern Rheumatology 2016;26:557-61

[3]Petri M, et al. Journal of Rheumatology 1992;19:265-9

[4]Naranjo CA, et al. Clinical Pharmacology and Therapeutics 1981;30:239-45

Disclosure of Interests:

None declared

Patient care experience with utilization of isolation precautions: systematic literature review and meta-analysis

BACKGROUND

Use of isolation precautions (IP) may represent a trade-off between reduced transmission of infectious pathogens and reduced patient satisfaction with their care.

OBJECTIVE

To perform a systematic literature review and meta-analysis to identify if and how IPs impact patients' care experiences.

DATA SOURCES

Medline, ClinicalTrials.gov, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, PsychInfo, HSRProj and Cochrane Library databases.

STUDY ELIGIBILITY CRITERIA

Interventional and observational studies published January 1990 to May 2019 were eligible for inclusion.

PARTICIPANTS

Patients admitted to an acute-care facility.

INTERVENTIONS

IPs versus no IPs.

METHODS

Six reviewers screened titles, abstracts and full text. Experience of care reported by patients using the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey was assessed as the outcome for the meta-analysis. Pooled odds ratios were calculated using the random-effects model. Heterogeneity was assessed using the I² value.

RESULTS

After screening 7073 titles and abstracts, 15 independent studies were included in the review. Pooling of unadjusted estimates from the HCAHPS survey demonstrated that IP patients were less likely to give top scores on questions pertaining to respect, communication, receiving assistance and cleanliness compared to the no-IP patients. Patients under IP with longer length of stay appeared to have more negative experiences with the care received during their stay compared to no IP.

CONCLUSIONS

Patients under IP were more likely to be dissatisfied with several aspects of patient care compared to patients not under IP. It is crucial to educate patients and healthcare workers in order to balance successful implementation of IP and patient care experiences, particularly in healthcare settings where it may be beneficial.

Isotope Effect on Energy Confinement Time and Thermal Transport in Neutral-Beam-Heated Stellarator-Heliotron Plasmas

The isotope effect on energy confinement time and thermal transport has been investigated for plasmas confined by a stellarator-heliotron magnetic field. This is the first detailed assessment of an isotope effect in a stellarator heliotron. Hydrogen and deuterium plasmas heated by neutral beam injection on the Large Helical Device have exhibited no significant dependence on the isotope mass in thermal energy confinement time, which is not consistent with the simple gyro-Bohm model. A comparison of thermal diffusivity for dimensionally similar hydrogen and deuterium plasmas in terms of the gyroradius, collisionality, and thermal pressure has clearly shown robust confinement improvement in deuterium to compensate for the unfavorable mass dependence predicted by the gyro-Bohm model.

Bridging veins and veins of the brainstem in microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm

OBJECTIVE In microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm, the bridging veins are dissected to provide the surgical corridors, and the veins of the brainstem may be mobilized in cases of venous compression. Strategy and technique in dissecting these veins may affect the surgical outcome. The authors investigated solutions for minimizing venous complications and reviewed the outcome for venous decompression. METHODS The authors retrospectively reviewed their surgical series of microvascular decompression for trigeminal neuralgia and hemifacial spasm in patients treated between 2005 and 2017. Surgical strategies included preservation of the superior petrosal vein and its tributaries, thorough dissection of the arachnoid sleeve that enveloped these veins, cutting of the inferior petrosal vein over the lower cranial nerves, and mobilization or cutting of the veins of the brainstem that compressed the nerve roots. The authors summarized the patient characteristics, operative findings, and postoperative outcomes according to the vascular compression types as follows: artery alone, artery and vein, and vein alone. They analyzed the data using chi-square and 1-way ANOVA tests. RESULTS The cohort was composed of 121 patients with trigeminal neuralgia and 205 patients with hemifacial spasm. The superior petrosal vein and its tributaries were preserved with no serious complications in all patients with trigeminal neuralgia. Venous compression alone and arterial and venous compressions were observed in 4% and 22%, respectively, of the patients with trigeminal neuralgia, and in 1% and 2%, respectively, of those with hemifacial spasm (p < 0.0001). In patients with trigeminal neuralgia, 35% of those with artery and venous compressions and 80% of those with venous compression alone had atypical neuralgia (p = 0.015). The surgical cure and recurrence rates of trigeminal neuralgias with venous compression were 60% and 20%, respectively, and with arterial and venous compressions the rates were 92% and 12%, respectively (p < 0.0001, p = 0.04). In patients with hemifacial spasm who had arterial and venous compressions, their recurrence rate was 60%, and that was significantly higher compared to other compression types (p = 0.0008). CONCLUSIONS Dissection of the arachnoid sleeve that envelops the superior petrosal vein may help to reduce venous complications in surgery for trigeminal neuralgia. Venous compression may correlate with worse prognosis even with thorough decompression, in both trigeminal neuralgia and hemifacial spasm.

Post-discharge oral antimicrobial use among hospitalized patients across an integrated national healthcare network

OBJECTIVES

Antimicrobial stewardship programmes have focused on reducing inappropriate inpatient antimicrobial prescribing, but several small studies have found a large portion of antimicrobial exposure occurs immediately after hospital discharge. In this study, we describe the prescribing of oral antimicrobials at hospital discharge across an integrated national healthcare system. At the hospital level, we also compare total inpatient antimicrobial use and post-discharge oral antimicrobial use.

METHODS

This retrospective cross-sectional study used national administrative data to identify all acute-care admissions during 2014-2016 within the Veterans Health Administration (VHA). We evaluated inpatient days of therapy (DOT) and post-discharge DOT, defined as oral outpatient antimicrobials dispensed at the time of hospital discharge. At the hospital level, inpatient DOT/100 admissions were compared with post-discharge DOT/100 admissions using Spearman's rank-order correlation.

RESULTS

There were 1 681 701 acute-care admissions across 122 hospitals, and 335 369 (19.9%) were prescribed an oral antimicrobial at discharge. Fluoroquinolones (38.3%) were the most common post-discharge antimicrobial. At the hospital level, median inpatient antimicrobial use was 331.3 (interquartile range (IQR) 284.9-367.9) DOT/100 admissions and median post-discharge use was 209.5 (IQR 181.5-239.6) DOT/100 admissions. Thirty-nine per cent of the total duration of antimicrobial exposure occurred after discharge. At the hospital-level, the metrics of inpatient DOT/100 admissions and post-discharge DOT/100 admissions were weakly positively correlated with rho=0.44 (p < 0.001).

CONCLUSIONS

A large proportion of antimicrobial exposure among hospitalized patients occurred immediately following discharge. Antimicrobial-prescribing at hospital discharge provides an opportunity for antimicrobial stewardship. Hospital-level stewardship metrics need to include both inpatient and post-discharge antimicrobial-prescribing to provide a comprehensive assessment of hospital-associated antimicrobial use.