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Background: To provide improved treatment for hallux valgus (HV), we sought to understand more about the pathophysiologic connection between flatfoot deformity and HV by comparing coronal plane alignment of the medial column of the foot for patients with isolated HV, isolated flatfoot, and combined HV-flatfoot vs controls., Methods: This study retrospectively assessed a consecutive series of 33 patients with combined symptomatic and radiographic HV and flatfoot, 33 isolated symptomatic HV, 33 isolated symptomatic flatfoot, and 33 controls. The medial column alignment was assessed in the coronal plane using 3-dimensional weightbearing computed tomography (WBCT); rotation was measured for the navicular, medial cuneiform, and first metatarsal (M1). The position of the first naviculocuneiform (NC) and tarsometatarsal (TMT) joints were determined., Results: M1 intrinsic pronation was significantly greater in patients with combined HV-flatfoot (-12.0 ± 7.0 degrees; P  < .001), isolated HV (-12.1 ± 6.6 degrees; P  < .001), and isolated flatfoot (-11.8 ± 8.5 degrees; P  < .001), compared with control patients (-19.4 ± 6.7 degrees). TMT was significantly more pronated in patients with combined HV-flatfoot (30.9 ± 6.2 degrees) compared with isolated flatfoot (25.3 ± 9.3 degrees; P  = .007), and control (25.9 ± 5.2 degrees; P  = .005), as it was in patients with isolated HV (33.2 ± 8.2 degrees) compared with isolated flatfoot ( P  < .001), and control ( P  < .001). NC was significantly more supinated in patients with combined HV-flatfoot (-23.7 ± 3.9 degrees) compared to isolated flatfoot (-18.0 ± 9.8 degrees; P  = .001), and control (-18.0 ± 4.5 degrees; P  < .001), as it was for patients with isolated HV (-24.8 ± 7.1 degrees) compared with isolated flatfoot ( P  = .003), and control ( P  < .001)., Conclusion: In our study, we found that patients with isolated HV, isolated flatfoot, or combined HV-flatfoot presented a similar increase in M1 intrinsic pronation of approximately 7.5 degrees, compared with controls. Moreover, patients with isolated HV or combined HV-flatfoot had greater TMT pronation and NC supination, compared with patients with isolated flatfoot and controls., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Cesar de Cesar Netto, MD, PhD, reports general disclosures of personal fees from CurveBeam and Ossio. All other authors declare no competing interests. Disclosure forms for all authors are available online.

Introduction: Few studies analysed the impact of different venous resection techniques on recurrence in patients with pancreatic ductal adenocarcinoma (PDAC). Primary aim was to compare local recurrence rate and disease-free survival (DFS) between patients who underwent pancreatectomy with tangential versus segmental resection of portal vein/superior mesenteric vein., Materials and Methods: All consecutive patients who underwent pancreatectomy with venous resection for PDAC between 2009 and 2019 were included. A propensity score matching (PSM) was used to reduce the effect of treatment selection bias., Results: Overall, 120 patients (68%) underwent pancreatectomy with tangential venous resection and 57 patients (32%) were submitted to pancreatectomy with segmental venous resection. After a median follow-up of 24 months, local recurrence was comparable between the two groups (tangential: n = 32/120, 26.7% versus segmental: n = 10/57, 17.5%; p = 0.58). The median DFS was 17 months (IQR 9-31) in patients who underwent tangential resection, as compared to 12 months (IQR 5-21) in those who underwent segmental resection (p = 0.049). After PSM (n = 106), the median DFS was 18 months (IQR 9-26) in the tangential resection group, and 12 months (IQR 5-21) in the segmental resection group (p = 0.17). In the PSM population, lymph node ratio (HR 4.83; p = 0.028) and tumor size >25 mm (HR 3.26; p = 0.007) were identified as determinants of local recurrence., Conclusion: Tangential venous resections are not associated with a higher rate of local recurrence. Long-term outcomes are more related to tumors characteristics than to venous resection techniques. A step-up approach to vein resection, with tangential resection being performed whenever technically feasible, should be strongly encouraged., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)

Purpose: Scapholunate dissociation is a common and significant injury to the wrist. Radiographs are important in the diagnosis of this injury and in the planning of treatment. The tangential radiograph view was described almost 40 years ago as a method for accurately measuring scapholunate gaps. The hand is positioned on a 20° foam rubber block and the thumb on the cassette, which positions the scaphoid and lunate articular surfaces parallel, without patient discomfort or effort. The goal of this study was to review this method with more recent data and in a larger group of patients., Methods: Radiographs of 31 patients who had scapholunate interosseous ligament tears and surgical repair over a 9 year period were retrospectively evaluated. Each of the four authors independently measured scapholunate gaps for posteroanterior and tangential views., Results: The tangential view gaps were significantly greater than the posteroanterior gaps overall. Similar results were found for borderline cases where the posteroanterior gap was less than 3 mm. Every tangential view gap measurement was greater than its respective posteroanterior gap with good inter-rater reliability., Conclusion: The tangential view is a reliable radiographic method to identify scapholunate gaps. It should be obtained when there is clinical concern for scapholunate dissociation, especially in patients with borderline posteroanterior gaps., (© 2022. The Author(s).)

Objective: Microsurgical resection of medial temporal brain arteriovenous malformations (AVMs) is typically conducted through 2 approaches: the orbitozygomatic-tangential and subtemporal-transcortical. Relative indications and outcomes for these techniques have not been formally compared., Methods: The cerebrovascular database of a quaternary center was reviewed for patients with medial temporal AVMs treated between January 1, 1997, and July 31, 2021. Demographic characteristics, lesion characteristics, surgical approaches, and outcomes were retrospectively analyzed and compared. Postoperative outcome testing was performed using the Montreal Cognitive Assessment and Global Quality of Life Scale., Results: Fifty-nine patients were assessed. Mean (standard deviation) age was 31 (18) years; 30 (51%) patients were male. Of the AVMs, 29 (49%) were left-sided and 30 (51%) were right-sided. The tangential approach was selected in 20 (34%) cases, whereas the transcortical technique was preferred in 39 (66%). Improved modified Rankin Scale status was significantly associated with the tangential resection technique both in the early postoperative period (P = 0.02) and at last follow-up (P = 0.01). Differences between the tangential and transcortical approaches were not significant with respect to new postoperative deficits (5/20 [25%] vs. 12/39 [31%], P = 0.87) or the presence of residual AVM on follow-up angiography (1/20 [6%] vs. 5/39 [14%], P = 0.65)., Conclusions: The orbitozygomatic-tangential strategy was associated with favorable functional and quality-of-life outcomes after medial temporal AVM resection. These benefits are likely to be attributable to minimization of temporal retraction, avoidance of brain transgression, and avoidance of traction on the vein of Labbé, rendering the orbitozygomatic-tangential approach the preferred option for cases that are anatomically amenable to either strategy., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Competing Interests: Conflicts of interest Dr Feng is a consultant for Cytrellis Biosystems, Inc and Soliton, Inc. Dr Gronbeck has no conflicts of interest to declare.

Background: Military neurosurgeons have long known that tangential cranial gunshot wounds can be associated with intracranial complications out of proportion to the external appearance of the injury. This phenomenon seems not to have been described in infancy., Observations: An infant suffered a massive, acute subdural hemorrhage from a contralateral tangential gunshot wound that did not facture the skull., Lessons: Similar to adults, infants are subject to catastrophic intracranial injury from gunshots that do not penetrate the skull. The nature of the injury in this case reflected distinctive aspects of the tissue characteristics and proportions of the infant head.

Purpose: To test the performances of a volumetric arc technique named ViTAT (Virtual Tangential-fields Arc Therapy) mimicking tangential field irradiation for whole breast radiotherapy., Methods: ViTAT plans consisted in 4 arcs whose starting/ending position were established based on gantry angle distribution of clinical plans for right and left-breast. The arcs were completely blocked excluding the first and last 20°. Different virtual bolus densities and thicknesses were preliminarily evaluated to obtain the best plan performances. For 40 patients with tumor laterality equally divided between right and left sides, ViTAT plans were optimized considering the clinical DVHs for OARs (resulting from tangential field manual planning) to constrain them: ViTAT plans were compared with the clinical tangential-fields in terms of DVH parameters for both PTV and OARs., Results: Distal angle values were suggested in the ranges [220°,240°] for the right-breast and [115°,135°] for the left-breast cases; medial angles were [60°,40°] for the right side and [295°,315°] for the left side, limiting the risk of collision. The optimal virtual bolus had -500 HU density and 1.5 cm thickness. ViTAT plans generated dose distributions very similar to the tangential-field plans, with significantly improved PTV homogeneity. The mean doses of ipsilateral OARs were comparable between the two techniques with minor increase of the low-dose spread in the range 2-15 Gy (few % volume); contralateral OARs were slightly better spared with ViTAT., Conclusion: ViTAT dose distributions were similar to tangential-fields. ViTAT should allow automatic plan optimization by developing knowledge-based DVH prediction models of patients treated with tangential-fields., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Volumetric modulated arc therapy (VMAT) has been implemented for left breast irradiation to reduce prescription dose to the heart and improve dose homogeneity across the targeted breast. Our in-house method requires application of a bolus during the optimization process with a target outside of the body, then removing the bolus during the final calculation in order to incorporate skin flash in VMAT plans. To quantify the dosimetric trade-offs between traditional 3D field-in-field tangents and VMAT with integrated skin flash for these patients, we compared nine consecutive patients who recently received radiation to their entire left breast but not their regional lymphatics. Tangent plans used non-divergent tangents of mixed energies and VMAT plans utilized four 6 MV arcs of roughly 260°. Mean dose to the heart, contralateral lung, and contralateral breast and their volume receiving 5%, 10%, and 20% of the prescription dose were higher in all nine VMAT plans than in the static tangential beam plans. For all critical structures, the mean VMAT DVH was higher in the low-dose region and crossed the 3D field-in-field DVH between 23.13% and 34.18% of the prescription dose (984.75-1454.70 cGy). However, the volume of the contralateral breast and heart receiving the prescription dose was slightly lower in the VMAT plans, but not statistically significant. VMAT provided superior homogeneity, with a mean homogeneity index of 9.41 ± 1.64 compared to 11.05 ± 1.82 for 3D tangents. Results indicate that VMAT spares the heart, contralateral lung, and contralateral breast from prescription dose at the cost of increasing their mean and low-dose volume and delivers a more homogenous dose distribution to the breast. For these reasons, VMAT is selectively applied at the request of the physician for left breast radiation without respiratory gating to spare the heart from prescription dose in cases of poor anatomical geometry., (© 2019 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

Radiotherapy to the breast after surgery sometimes requires adjoining nodes to be included in the treatment volume. In these cases, the traditional approach has been a complex 3-Dimensional Conformal Radiotherapy (3DCRT) beam arrangement which can result in significant dose heterogeneity at the beam junctions. A Volumetric Modulated Arc Therapy (VMAT) beam arrangement has previously been proposed for breast cases, where the chest wall/breast is treated with a limited angle (partial arc) tangential VMAT technique (Virén et al. [2015] Radiat Oncol. 10:79). In our study, this approach is extended to breast and chest wall cases with adjoining nodes by adding a separate conventional VMAT arc field specifically limited to the superior nodes. This VMAT method was implemented using a semiautomated approach on 27 patients, and the resultant plan compared to a monoisocentric 3DCRT plan. Plan statistics, Dose-Volume Histogram (DVH) analysis and Radiation Oncologist (RO) preference were assessed. When compared to the 3DCRT technique, the VMAT planning method was found to result in better target volume coverage, high doses to organs at risk (OAR) were reduced but greater OAR volumes received low doses. Having said that, the volume receiving low doses with this tangential VMAT technique was less than that of other VMAT planning methods described in the literature, and the integral dose was less than the 3DCRT method. The VMAT technique also resulted in more robust junction doses that the 3DCRT method. RO review found that the VMAT technique was preferred in 81% of cases. Specifically, the VMAT plans were preferred in all categories of patients except left chest wall cases where the intermammary nodes were also treated. The VMAT technique described here is a useful addition to the treatment options available for breast/chest wall and nodal patients., (© 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

For the correct interpretation of results of tangential electrokinetic measurements with porous materials, in particular, composite/asymmetric membranes on porous supports, it is necessary to have the data available for various channel heights. In some kinds of equipment, the variation of channel height is technically possible only for a range of relatively large heights. This communication shows that under these conditions, the fluid flow can become undeveloped and the conventional approaches to the interpretation of electrokinetic measurements should be modified accordingly. In particular, the dependence of streaming-current coefficient on the channel height becomes sub-linear. If the experimental data are available only for larger channel heights, this can be mistakenly taken for the manifestation of contribution of porous sub-structure to the streaming current. In this communication, we investigate electrokinetic phenomena in undeveloped flows both numerically and experimentally. We confirm that the aforementioned sub-linearity occurs for nonporous as well as porous substrates. We also demonstrate that the channel heights estimated from the volume flow rate by using numerical simulations of undeveloped flows are in very good agreement with the reference values obtained from the electrical conductance (in contrast to the values estimated by using the conventional approach of Hagen-Poiseuille equation). The numerical fitting of channel-height dependences of streaming-current coefficient enables us to separate the contributions of external surface and porous sub-structure (in case of porous substrates) and obtain quite reasonable values of (effective) zeta-potentials in both cases. Nonetheless, the accuracy of experimental data deteriorates with increasing channel height, so it is generally advisable to vary the heights within a range below 100-150 μm., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The discovery, approximately 15 years ago, that cortical GABAergic interneurons originate outside the pallium has revolutionized our understanding of the development of the cerebral cortex. It is now clear that glutamatergic pyramidal cells and GABAergic interneurons follow largely distinct development programs, a notion that has challenged our views on how these neurons assemble to form precise neural circuits. In this review, I summarize our current knowledge of the mechanisms that control the migration of neocortical interneurons, a process that can be subdivided into three consecutive phases: migration to the cortex, intracortical dispersion, and layering., (© 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)