In this article, we demonstrate that for any positive integer $n$, the knot surgery $4$-manifold $E(n)_K$ has a handle decomposition without $1$- and $3$-handles. Here, $K$ represents either a fibered two-bridge knot $C(2ε_1, 2ε_2,\cdots, 2ε_{2g})$ ($ε_i \in \{ 1, -1\}$) in Conway's notation or a Stallings knot $K_m$ ($m \in \mathbb{Z}$).
Santi Anchalee, Nalinee Kovitwanawong, Thitaporn Saetung
et al.
Abstract Background This study aimed to evaluate the prediction of difficult intubation using ultrasonographic skin-to-vocal-cord measurements in obese Thai patients undergoing elective general anesthesia. Methods This prospective observational study was conducted from December 2020 to June 2023. Total 90 obese patients (body mass index ≥ 30 kg/m2) aged 18–60 years with an American Society of Anesthesiologists physical status classification of 2–3 requiring elective surgery under general anesthesia with oral endotracheal intubation in operating theatres were included. Anesthesiologists assessed the airway and measured the skin-to-vocal-cord distance using ultrasonography in the median coronal plane in the closed-mouth supine position. The primary outcome was difficult laryngoscopy, defined as a laryngoscopic view grade 3 or 4 on the Cormack–Lehane scale. Results The incidence of difficult laryngoscopy was 13.33% (12/90 patients). The median (interquartile range) body mass index in the difficult and easy intubation groups was 44.7 kg/m2 (34.8–47.9) and 41.7 kg/m2 (36.7–47.1), respectively (p = 0.929). The mean skin-to-vocal-cord distances (DSVC) in the difficult and easy intubation groups were 20.1 ± 7.2 mm and 16.3 ± 4.9 mm (p = 0.022), respectively. The median time for tracheal intubation in the difficult and easy intubation groups was 61.5 [50.2–120] s and 40 [30–56.8] s, respectively (p < 0.001). Multivariable logistic regression revealed that male sex and skin-to-vocal-cord distance ≥ 19.2 mm (area under the curve, 0.67) were significantly associated with difficult intubation. In sensitivity analysis excluding cases performed by anesthesiologists, DSVC ≥ 19.2 mm remained the only significant predictor of difficult intubation. Conclusions In obese Thai patients, A skin-to-vocal-cord distance of ≥ 19.2 mm measured by ultrasonography was associated with difficult laryngoscopy and remained consistent across sensitivity analyses. These factors may help predict difficult intubation. However, the modest diagnostic performance suggests that DSVC should not be used as a standalone predictor. Trial registration Thai Clinical Trials Registry (TCTR20250616007); registered on June 16, 2025.
Orthognathic surgery is a crucial intervention for correcting dentofacial skeletal deformities to enhance occlusal functionality and facial aesthetics. Accurate postoperative facial appearance prediction remains challenging due to the complex nonlinear interactions between skeletal movements and facial soft tissue. Existing biomechanical, parametric models and deep-learning approaches either lack computational efficiency or fail to fully capture these intricate interactions. To address these limitations, we propose Neural Implicit Craniofacial Model (NICE) which employs implicit neural representations for accurate anatomical reconstruction and surgical outcome prediction. NICE comprises a shape module, which employs region-specific implicit Signed Distance Function (SDF) decoders to reconstruct the facial surface, maxilla, and mandible, and a surgery module, which employs region-specific deformation decoders. These deformation decoders are driven by a shared surgical latent code to effectively model the complex, nonlinear biomechanical response of the facial surface to skeletal movements, incorporating anatomical prior knowledge. The deformation decoders output point-wise displacement fields, enabling precise modeling of surgical outcomes. Extensive experiments demonstrate that NICE outperforms current state-of-the-art methods, notably improving prediction accuracy in critical facial regions such as lips and chin, while robustly preserving anatomical integrity. This work provides a clinically viable tool for enhanced surgical planning and patient consultation in orthognathic procedures.
In recent years, significant progress has been made in the field of surgical scene understanding, particularly in the task of Visual Question Localized-Answering in robotic surgery (Surgical-VQLA). However, existing Surgical-VQLA models lack deep reasoning capabilities and interpretability in surgical scenes, which limits their reliability and potential for development in clinical applications. To address this issue, inspired by the development of Reasoning Multimodal Large Language Models (MLLMs), we first build the Surgery-R1-54k dataset, including paired data for Visual-QA, Grounding-QA, and Chain-of-Thought (CoT). Then, we propose the first Reasoning MLLM for Surgical-VQLA (Surgery-R1). In our Surgery-R1, we design a two-stage fine-tuning mechanism to enable the basic MLLM with complex reasoning abilities by utilizing supervised fine-tuning (SFT) and reinforcement fine-tuning (RFT). Furthermore, for an efficient and high-quality rule-based reward system in our RFT, we design a Multimodal Coherence reward mechanism to mitigate positional illusions that may arise in surgical scenarios. Experiment results demonstrate that Surgery-R1 outperforms other existing state-of-the-art (SOTA) models in the Surgical-VQLA task and widely-used MLLMs, while also validating its reasoning capabilities and the effectiveness of our approach. The code and dataset will be organized in https://github.com/FiFi-HAO467/Surgery-R1.
The U.S. Food and Drug Administration has cautioned that prenatal exposure to anesthetic drugs during the third trimester may have neurotoxic effects; however, there is limited clinical evidence available to substantiate this recommendation. One major scientific question of interest is whether such neurotoxic effects might be due to surgery, anesthesia, or both. Isolating the effects of these two exposures is challenging because they are observationally equivalent, thereby inducing an extreme positivity violation. To address this, we adopt the separable effects framework of Robins and Richardson (2010) to identify the effect of anesthesia (alone) by blocking effects through variables that are assumed to completely mediate the causal pathway from surgery to the outcome. We apply this approach to data from the nationwide Medicaid Analytic eXtract (MAX) from 1999 through 2013, which linked 16,778,281 deliveries to mothers enrolled in Medicaid during pregnancy. Furthermore, we assess the sensitivity of our results to violations of our key identification assumptions.
Abstract Cancer significantly contributes to the unfavorable prognosis of coronavirus disease 2019 (COVID-19) patients. The efficacy and safety of azvudine and nirmatrelvir/ritonavir (Paxlovid) in cancer patients with COVID-19 remain uncertain. Therefore, we designed a comprehensive retrospective study encompassing clinical data of 32,864 hospitalized COVID-19 patients, 691 of whom were cancer patients treated with azvudine and 200 were cancer patients treated with Paxlovid. After 2:1 propensity score matching, 397 patients in the azvudine group and 199 patients in the Paxlovid group were enrolled. Cox regression analysis revealed the risk of all-cause death (HR: 1.84, 95% CI: 1.059–3.182, P = 0.030) and composite disease progression (HR: 1.70, 95% CI: 1.043–2.757, P = 0.033) were greater in the Paxlovid group than in the azvudine group. Two sensitivity analyses confirmed the robustness of our findings. The safety analysis of adverse events revealed no statistically significant differences between the two groups. In conclusion, we carried out the first analysis to compare the efficacy and safety of azvudine and Paxlovid in cancer patients with COVID-19 and demonstrated that azvudine significantly reduced the risk of all-cause death and composite disease progression among cancer patients with COVID-19 compared with Paxlovid.
Ammad Javaid Chaudhary, Abdulmalik Saleem, Muhammad Shahzil
et al.
Colorectal cancer (CRC) continues to be a significant global health issue contributing to a high mortality rate. Despite advancements in treatment, the risk of recurrence remains due to inherent mutations and the rapid turnover of intestinal mucosa. We present an exceptionally rare case of CRC metastasis to the duodenum in a 42-year-old female who has been compliant with postsurgical surveillance. Despite previous negative surveillance results, elevated CEA levels and a 3-cm mesenteric mass were detected, raising concerns for carcinoma, which was later confirmed by biopsy. The tumor board deemed her ineligible for surgery due to vascular involvement, leading to palliative care and an attempt at neoadjuvant therapy. Vigilant monitoring is crucial for early detection and intervention.
Diseases of the digestive system. Gastroenterology
Wiktor Stopyra, Oleksiy Voytsekhivskyy, Andrzej Grzybowski
<b>Purpose:</b> To compare the accuracy of seven artificial intelligence (AI)-based intraocular lens (IOL) power calculation formulas in medium-long Caucasian eyes regarding the root-mean-square absolute error (RMSAE), the median absolute error (MedAE) and the percentage of eyes with a prediction error (PE) within ±0.5 D. <b>Methods:</b> Data on Caucasian patients who underwent uneventful phacoemulsification between May 2018 and September 2023 in MW-Med Eye Center, Krakow, Poland and Kyiv Clinical Ophthalmology Hospital Eye Microsurgery Center, Kyiv, Ukraine were reviewed. Inclusion criteria, i.e., complete biometric and refractive data, were applied. Exclusion criteria were as follows: intraoperative or postoperative complications, previous eye surgery or corneal diseases, postoperative BCVA less than 0.8, and corneal astigmatism greater than 2.0 D. Prior to phacoemulsification, IOL power was computed using SRK/T, Holladay1, Haigis, Holladay 2, and Hoffer Q. The refraction was measured three months after cataract surgery. Post-surgery intraocular lens calculations for Hill-RBF 3.0, Kane, PEARL-DGS, Ladas Super Formula AI (LSF AI), Hoffer QST, Karmona, and Nallasamy were performed. RMSAE, MedAE, and the percentage of eyes with a PE within ±0.25 D, ±0.50 D, ±0.75 D, and ±1.00 were counted. <b>Results:</b> Two hundred fourteen eyes with axial lengths ranging from 24.50 mm to 25.97 mm were tested. The Hill-RBF 3.0 formula yielded the lowest RMSAE (0.368), just before Pearl-DGS (0.374) and Hoffer QST (0.378). The lowest MedAE was achieved by Hill-RBF 3.0 (0.200), the second-lowest by LSF AI (0.210), and the third-lowest by Kane (0.228). The highest percentage of eyes with a PE within ±0.50 D was obtained by Hill-RBF 3.0, LSF AI, and Pearl-DGS (86.45%, 85.51%, and 85.05%, respectively). <b>Conclusions:</b> The Hill-RBF 3.0 formula provided highly accurate outcomes in medium-long eyes. All studied AI-based formulas yielded good results in IOL power calculation.
In image-guided liver surgery, the initial rigid alignment between preoperative and intraoperative data, often represented as point clouds, is crucial for providing sub-surface information from preoperative CT/MRI images to the surgeon during the procedure. Currently, this alignment is typically performed using semi-automatic methods, which, while effective to some extent, are prone to errors that demand manual correction. Point cloud correspondence-based registration methods are promising to serve as a fully automatic solution. However, they may struggle in scenarios with limited intraoperative surface visibility, a common challenge in liver surgery, particularly in laparoscopic procedures, which we refer to as complete-to-partial ambiguity. We first illustrate this ambiguity by evaluating the performance of state-of-the-art learning-based point cloud registration methods on our carefully constructed in silico and in vitro datasets. Then, we propose a patches-to-partial matching strategy as a plug-and-play module to resolve the ambiguity, which can be seamlessly integrated into learning-based registration methods without disrupting their end-to-end structure. It has proven effective and efficient in improving registration performance for cases with limited intraoperative visibility. The constructed benchmark and the proposed module establish a solid foundation for advancing applications of point cloud correspondence-based registration methods in image-guided liver surgery.
Introduction: Pseudoaneurysms of the pancreaticoduodenal arcade are rare, accounting for approximately 2% of all visceral artery aneurysms. They typically arise as complications of chronic pancreatitis, peptic ulcer disease, trauma, pancreatic and biliary surgery, or pancreas transplantation. Diagnosis often occurs only after rupture, leading to life-threatening internal bleeding. Bleeding may occur within a pseudocyst, with blood passing through the Vater’s papilla into the digestive tract, or may result in the formation of a retroperitoneal hematoma that can rupture into the abdominal cavity, causing hemoperitoneum. The cell-saver is a tool that can be utilized for intraoperative blood cell salvage and autologous transfusions.
Case Report: Our patient, a 54-year-old male, an untreated alcoholic with no prior medical history or documented treatment, presented to the Clinic for Emergency Surgery at the University Clinical Center of Serbia with a sudden onset of upper abdominal pain. A quick ultrasound of the abdomen was performed, followed by an urgent CT scan of the chest and abdomen, revealing a hematoma extending from the right retroperitoneum and mesentery of the intestine, measuring 150x109x180mm in diameter, with signs of active bleeding in the region beneath the pancreas, indicative of hemoperitoneum. Due to hemodynamic instability, accompanied by a drop in arterial blood pressure and hemoglobin levels, an urgent laparotomy was performed. Active bleeding was identified from a ruptured pseudoaneurysm originating from the pancreaticoduodenal arcade. Hemostasis was achieved followed by tamponade, and the tampons were removed 30 hours post-surgery. The patient remained hemodynamically stable thereafter, recovered well from the surgery, and was discharged home in good general condition.
Intraoperatively, we utilized the Cell-saver to collect the patient’s blood and subsequently administered autologous transfusion.
Conclusion: In patients with chronic pancreatitis presenting with sudden abdominal pain and hemodynamic instability accompanied by a drop in arterial pressure, hemoglobin, and hematocrit levels, the possibility of a ruptured pseudoaneurysm in the pancreatic or peripancreatic region should be considered. Timely diagnosis and prompt surgical intervention are crucial for a successful outcome. Effective collaboration among radiologists, anesthesiologists, and surgeons is essential. The utilization of the Cell-saver system significantly aids in maintaining cardiac output and hemodynamic stability in these patients.
Marie Abitbol, Caroline Dufaure de Citres, Gabriela Rudd Garces
et al.
During the last twenty years, minimal white spotting associated with blue eyes was selected by feline breeders to create the Altai, Topaz, and Celestial breeds. Additionally, certain breeders introduced this trait in their lineages of purebred cats. The trait has been called “dominant blue eyes (DBE)” and was confirmed to be autosomal dominant in all lineages. DBE was initially described in outbred cats from Kazakhstan and Russia and in two purebred lineages of British cats from Russia, as well as in Dutch Maine Coon cats, suggesting different founding effects. We have previously identified two variants in the <i>Paired Box 3 (PAX3)</i> gene associated with DBE in Maine Coon and Celestial cats; however, the presence of an underlying variant remains undetermined in other DBE breeding lines. Using a genome-wide association study, we identified a single region on chromosome C1 that was associated with DBE in British cats. Within that region, we identified <i>PAX3</i> as the strongest candidate gene. Whole-genome sequencing of a DBE cat revealed an RD-114 retrovirus LTR (long terminal repeat) insertion within <i>PAX3</i> intron 4 (namely NC_018730.3:g.206975776_206975777insN[433]) known to contain regulatory sequences. Using a panel of 117 DBE cats, we showed that this variant was fully associated with DBE in two British lineages, in Altai cats, and in some other DBE lineages. We propose that this NC_018730.3:g.206975776_206975777insN[433] variant represents the <i>DBE<sup>ALT</sup></i> (<i>Altai Dominant Blue Eye</i>) allele in the domestic cat. Finally, we genotyped DBE cats from 14 lineages for the three <i>PAX3</i> variants and showed that they were not present in four lineages, confirming genetic heterogeneity of the DBE trait in the domestic cat.
Umile Giuseppe Longo, Alessandro Mazzola, Stefano Campi
et al.
<i>Background and Objectives:</i> Knee osteoarthritis is a serious burden for modern countries. Timing of surgery and treatment choice are still a matter of controversy in the orthopedic literature. The purpose of this study was to ascertain the incidence and hospitalization trends of high tibial osteotomy in Italy from 2001 to 2016. <i>Materials and Methods:</i> Data are sourced from the National Hospital Discharge Reports (SDO) of the Italian Ministry of Health between 2001 and 2016. <i>Results:</i> A total of 34,402 high tibial osteotomies were performed over the study period in Italy. The cumulative incidence was 3.6 cases per 100,000 residents. The age classes 50–54, 55–59 showed the higher number of procedures. In pediatric patients (0–19 years), high tibial osteotomies are also largely performed. The majority of patients having surgery were men with a M/F ratio of 1.5. The mean age of patients was 44.2 ± 19.2 years. Males were significantly younger than females (43.3 ± 20.7 vs. 45.6 ± 17.7). The average length of hospitalization was 6.1 ± 7.3 days. Over the course of the analysis, a declining trend in hospital stay length was seen. The main primary diagnosis codes were “Varus knee” (736.42 ICD-9-CM code, 33.9%), “Osteoarthrosis, localized, primary, leg region” (715.16 ICD-9-CM code, 9.5%). <i>Conclusions:</i> Over the study period, high tibial osteotomies in Italy almost halved. Varus deformity and knee osteoarthritis are the leading causes requiring high tibial osteotomy. Except for the pediatric setting, results showed that from the 20–24 age class to the 50–54 age class, there was an increasing request for knee osteotomy, whereas in those aged >60 years, the incidence progressively decreased. The evident decline in HTO performed over the years in Italy seems to reflect a minor role for knee osteotomy in the management of knee OA, as it seems to be primarily reserved for younger male patients.
Eric Segalerba, Gabriele Dini Ciacci, Maurizio Quadrio
et al.
Nasal breathing difficulties (NBD) are widespread and difficult to diagnose; the failure rate of their surgical corrections is high. Computational Fluid Dynamics (CFD) enables diagnosis of NBD and surgery planning, by comparing a pre-operative (pre-op) situation with the outcome of virtual surgery (post-op). An equivalent comparison is involved when considering distinct anatomies in the search for the functionally normal nose. Currently, this comparison is carried out in more than one way, under the implicit assumption that results are unchanged, which reflects our limited understanding of the driver of the respiratory function. The study describes how to set up a meaningful comparison. A pre-op anatomy, derived via segmentation from a CT scan, is compared with a post-op anatomy obtained via virtual surgery. State-of-the-art numerical simulations for a steady inspiration carry out the comparison under three types of global constraints, derived from the field of turbulent flow control: a constant pressure drop (CPG) between external ambient and throat, a constant flow rate (CFR) through the airways and a constant power input (CPI) from the lungs can be enforced. A significant difference in the quantities of interest is observed depending on the type of comparison. Global quantities (flow rate, pressure drop, nasal resistance) as well as local ones are affected. The type of flow forcing affects the outcome of the comparison between pre-op and post-op anatomies. Among the three available options, we argue that CPG is the least adequate. Arguments favouring either CFR or CPI are presented.
We determine the adjoint Reidemeister torsion of a $3$-manifold obtained by some Dehn surgery along $K$, where $K$ is either the figure-eight knot or the $5_2$-knot. As in a vanishing conjecture, we consider a similar conjecture and show that the conjecture holds for the 3-manifold.
Michael Dyck, Alistair Weld, Julian Klodmann
et al.
During brain tumour resection, localising cancerous tissue and delineating healthy and pathological borders is challenging, even for experienced neurosurgeons and neuroradiologists. Intraoperative imaging is commonly employed for determining and updating surgical plans in the operating room. Ultrasound (US) has presented itself a suitable tool for this task, owing to its ease of integration into the operating room and surgical procedure. However, widespread establishment of this tool has been limited because of the difficulty of anatomy localisation and data interpretation. In this work, we present a robotic framework designed and tested on a soft-tissue-mimicking brain phantom, simulating intraoperative US (iUS) scanning during brain tumour surgery.
Hossein Niknahad, Ali Nadgaran, Sepideh Alidaee
et al.
Cholestasis is not only influences the hepatic function but also damages many other organs. Lung injury is a critical secondary organ damage associated with cholestasis/cirrhosis. Pulmonary histopathological alterations, respiratory distress, and hypoxia are related to cholestasis/cirrhosis-induced lung injury. It has been found that oxidative stress plays a crucial role in this complication. The current study was designed to investigate the effect of N-acetyl cysteine (NAC) and dithiothreitol (DTT) as thiol-reducing and antioxidant agents against cholestasis-induced lung injury. Bile duct ligated (BDL) rats were monitored for the presence of inflammatory cells, TNF-α, and IgG levels in their broncho-alveolar fluid (BALF) at scheduled time intervals (3, 7, 14, and 28 days post-BDL surgery). These markers reached their highest level in the BALF of BDL rats on day 28 after the surgery. Therefore, in another set of experiments, the BDL animals were treated with NAC (100 and 300 mg/kg/day, i.p, for 28 consecutive days) and DTT (10 and 20 mg/kg/day, i.p, for 28 consecutive days). Meanwhile, a significant increase in the levels of TNF-α and IgG was detected in the BALF of BDL rats. The BALF level of neutrophils, monocytes, and lymphocytes was also significantly increased in cholestatic animals. A significant increase in lung tissue biomarkers of oxidative stress was detected in the BDL rats. It was found that NAC and DTT could significantly blunt pulmonary damage induced by cholestasis. The effects of these agents on oxidative stress biomarkers and inflammatory response seem to play a pivotal role in their mechanisms of protective properties.