To be thorough or tailored: influence of the arachnoid dissection range on the surgical outcomes of microvascular decompression for hemifacial spasm.

BACKGROUND: As one of the most fundamental elements in exposure and decompression, the dissection of arachnoid has been rarely correlated with the surgical results in studies on Microvascular decompression (MVD) procedures for Hemifacial spasm (HFS). MATERIALS AND METHODS: Patients' records of the HFS cases treated with MVD from January 2016 to December 2021 in our center was retrospectively reviewed. The video of the procedures was inspected thoroughly to evaluate the range of dissection of arachnoid. Four areas were defined in order to facilitate the evaluation of the dissection range. The correlation between the arachnoid dissection and the surgical outcomes were analyzed. RESULTS: The arachnoid structures between the nineth cranial nerve and the seventh, eighth cranial nerves were dissected in all cases, other areas were entered based on different consideration. The rate of neurological complications of the extended dissection pattern group was higher than that of the standard pattern group (P < 0.05). The procedures in which the arachnoid structure above the vestibulocochlear nerve was dissected, led to more neurological complications (P < 0.05). CONCLUSION: Thorough dissection as an initial aim for all cases was not recommended in MVD for HFS, arachnoid dissection should be tailored to achieving safety and effectiveness during the procedure.

Educational stereoscopic representation of a step-by-step brain white fiber dissection according to Klingler's method.

BACKGROUND: Understanding and teaching the three-dimensional architecture of the brain remains difficult because of the intricate arrangement of grey nuclei within white matter tracts. Although cortical area functions have been well studied, educational and three-dimensional descriptions of the organization of deep nuclei and white matter tracts are still missing. OBJECTIVE: We propose herein a detailed step-by-step dissection of the lateral aspect of a left hemisphere using the Klingler method and provide high-quality stereoscopic views with the aim to help teach medical students or surgeons the three-dimensional anatomy of the brain. METHODS: Three left hemispheres were extracted and prepared. Then, according to the Klingler method, dissections were carried out from the lateral aspect. Photographs were taken at each step and were modified to provide stereoscopic three-dimensional views. RESULTS: Gray and white structures were described: cortex, claustrum, putamen, pallidum, caudate nucleus, amygdala; U-fibers, external and internal capsules, superior longitudinal fasciculus, frontal aslant fasciculus, uncinate fasciculus, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, corticospinal fasciculus, corona radiata, anterior commissure, and optic radiations. CONCLUSION: This educational stereoscopic presentation of an expert dissection of brain white fibers and basal ganglia would be of value for theoretical or hands-on teaching of brain anatomy; labeling and stereoscopy could, moreover, improve the teaching, understanding, and memorizing of brain anatomy. In addition, this could be also used for the creation of a mental map by neurosurgeons for the preoperative planning of brain tumor surgery.

Exposure of Hoffa Fractures Is Improved by Posterolateral and Posteromedial Extensile Approaches: A Qualitative and Quantitative Anatomical Study.

BACKGROUND: The current literature lacks recommendations regarding surgical approaches to best visualize and reduce Hoffa fractures. The aims of this study were to (1) define surgical corridors to the posterior portions of the lateral and medial femoral condyles and (2) compare the articular surface areas visible with different approaches. METHODS: Eight fresh-frozen human cadaveric knees (6 male and 2 female donors; mean age, 68.2 ± 10.2 years) underwent dissection simulating 6 surgical approaches to the distal femur. The visible articular surface areas for each approach were marked using an electrocautery device and subsequently analyzed using image-processing software. The labeled areas of each femoral condyle were statistically compared. RESULTS: At 30° of flexion, visualization of the posterior portions of the lateral and medial femoral condyles was not possible by lateral and medial parapatellar approaches, as only the anterior 29.4% ± 2.1% of the lateral femoral condyle and 25.6% ± 2.8% of the medial condyle were exposed. Visualization of the lateral femoral condyle was limited by the posterolateral ligamentous structures, hence a posterolateral approach only exposed its central (13.1% ± 1.3%) and posterior (12.4% ± 1.1%) portions. Posterolateral extension by an osteotomy of the lateral femoral epicondyle significantly improved the exposure to 53.4% ± 2.7% and, when combined with a Gerdy's tubercle osteotomy, to 70.9% ± 4.1% (p < 0.001). For the posteromedial approach, an arthrotomy between the anteromedial retinaculum and the superficial medial collateral ligament, and one between the posterior oblique ligament and the medial gastrocnemius tendon, allowed visualization of the central (13.5% ± 2.2%) and the posterior (14.6% ± 2.3%) portions of the medial femoral condyle, while a medial femoral epicondyle osteotomy significantly improved visualization to 66.1% ± 5.5% (p < 0.001). CONCLUSIONS: Visualization of the posterior portions of the femoral condyles is limited by the specific anatomy of each surgical corridor. Extension by osteotomy of the femoral epicondyles and Gerdy's tubercle significantly improved articular surface exposure of the femoral condyles. CLINICAL RELEVANCE: Knowledge of the surgical approach-specific visualization of the articular surface of the femoral condyles might be helpful to properly reduce small Hoffa fragments.

The Effect of Cold Saline Irrigation of Dissection Planes in Rhinoplasty on Postoperative Edema and Ecchymosis.

BACKGROUND: Periorbital edema and ecchymosis are frequently encountered after rhinoplasty and may be distressing to patients. Cold therapy is frequently employed in rhinoplasty to reduce postoperative edema and ecchymosis. PURPOSE: The aim of this study was to evaluate the effect of cold saline irrigation (CSI) of dissection planes in rhinoplasty on postoperative edema and ecchymosis. STUDY DESIGN, SETTING, SAMPLE: The investigators designed a retrospective cohort study. The data of patients who underwent rhinoplasty in our clinic between January 2021 and January 2023 were scanned. Patients who underwent primary open rhinoplasty from the same surgeon and standard rhinoplasty steps were applied in the same way and order were included in the study. Patients who had systemic diseases and previous nose surgery, and patients whose photographs could not be accessed from the photograph archive were excluded. PREDICTOR VARIABLE: According to whether CSI was applied to the dissection plans during rhinoplasty, the patients were divided into the CSI group and the control group (without CSI). MAIN OUTCOME VARIABLES: Patients' grades of periorbital edema and ecchymosis were the main outcome variables. The differences of outcome variables were compared between the 2 groups. COVARIATES: Demographics (age, sex), and surgical detail (duration of surgery) were collected as covariates. ANALYSES: The numerical variables were compared between the two groups using the student's t-test and Mann-Whitney U test, whereas the categorical variables were compared using Pearson's χ2 and Fisher's exact tests. P < .05 was considered statistically significant. RESULTS: Among the 167 patients who met the inclusion criteria, 60 patients were randomly selected, 30 patients in each group. No statistically significant difference was found between the two groups in terms of age (P = .45) and sex (P = .27). The mean ecchymosis grade was statistically significant lower in the CSI group than in the control group for all evaluation times (P < .05). Similarly, the mean edema grade was statistically significant lower in the CSI group than in the control group for all evaluation times, with the exception of the 10th and 15th day (P < .05). CONCLUSION AND RELEVANCE: CSI of the dissection planes in rhinoplasty reduced the development of periorbital edema and ecchymosis. This procedure is straightforward, inexpensive, and effective.

A novel miniature flexible robotic system for endoscopic mucosal dissection: an animal experimental study.

Endoscopic submucosal dissection (ESD) is a standard treatment for early gastrointestinal cancer due to its higher rate of en-bloc resection and lower recurrence rate. However, the technical challenges lead to long learning curve and high risks of adverse events. A gastrointestinal flexible robotic-tool system (GIFTS) was proposed to reduce the difficulty and shorten the learning curve of novices. This is an animal study to evaluate the feasibility of GIFTS in ESD. The GIFTS provides a total of 13 degrees of freedom within 10 mm in diameter and variable stiffness function to achieve endoscopic intervention and submucosal dissection with the cooperation of two flexible robotic instruments. One esophageal and four colorectal ESDs in five porcine models were performed. In all five ESD procedures, the GIFTS was successfully intubated and submucosal dissection was completed without perforation or significant bleeding, and there was no system fault. The mean operative time was 99 min, and the mean size of the specimen was 151 mm2. The fifth experiment showed significantly better results than the first one. In vivo animal experiments confirmed the feasibility of GIFTS in performing ESD. The control of GIFTS is friendly to inexperienced beginners, which will help reduce the technical challenges of ESD and shorten the learning curve of endoscopists.

Complete mesocolic excision for colon cancer: current status and controversies.

According to Hohenberger's original description, complete mesocolic excision for colon cancer involves precise dissection of the avascular embryonic plane between the parietal retroperitoneum and visceral peritoneum of the mesocolon. This ensures mesocolic integrity, access to high ligation of the supplying vessels at their origin and an associated extended lymphadenectomy. Results from centres which have adopted this approach routinely have demonstrated that oncological outcomes can be improved by the rigorous implementation of established principles of cancer surgery. Meticulous anatomical dissection along embryonic planes is a well-established principle of precision cancer surgery used routinely by the specialist colorectal surgeon. Therefore, the real question concerns the need for true central vascular ligation and associated extended (D3) lymphadenectomy or otherwise, particularly along the superior mesenteric vessels when performing a right colectomy. Whether this approach results in improved overall or disease-free survival remains unclear and its role remains controversial particularly given the potential for significant morbidity associated with a more extensive central vascular dissection. Current literature is limited by considerable bias, as well as inconsistent and variable terminology, and the results of established randomized trials are awaited. As a result of the current state of equipoise, various national guidelines have disparate recommendations as to when complete mesocolic excision should be performed if at all. This article aims to review the rationale for and technical aspects of complete mesocolic excision, summarize available short and long term outcome data and address current controversies.

Novel quantitative assessment indicators for efficiency and precision of endoscopic submucosal dissection in animal training models by analyzing an electrical surgical unit.

OBJECTIVES: Although endoscopic submucosal dissection (ESD) training is important, quantitative assessments have not been established. This study aimed to explore a novel quantitative assessment system by analyzing an electrical surgical unit (ESU). METHODS: This was an ex vivo study. Step one: to identify the novel efficiency indicators, 20 endoscopists performed one ESD each, and we analyzed correlations between their resection speed and electrical status. Step two: to identify the novel precision indicators, three experts and three novices performed one ESD each, and we compared the stability of the electrical status. Step three: three novices in step two performed 19 additional ESDs, and we analyzed the learning curve using novel indicators. RESULTS: Step one: the percentage of total activation time (AT) of ESU in the procedure time (ß coefficient, 0.80; P < 0.01) and AT required for submucosal dissection (ß coefficient, -0.57; P < 0.01) were significantly correlated with the resection speed. Step two: coefficient of variation of the AT per one pulse (0.16 [range, 0.13-0.17] vs. 0.26 [range, 0.20-0.41], P = 0.049) and coefficient of variation of the peak electric power per pulse during mucosal incision (0.14 [range, 0.080-0.15] vs. 0.25 [range, 0.24-0.28], P = 0.049) were significantly lower in the experts than in the novices. Regarding the learning curve, the percentage of total AT of ESU in the procedure time and AT required for submucosal dissection had a trend of improvement. CONCLUSION: Novel indicators identified by analyzing ESU enable quantitative assessment for endoscopist's skill.

Endoscopic submucosal dissection assisted by adaptive traction: results of the first 54 procedures.

BACKGROUND : Good submucosal exposure is key to successful endoscopic submucosal dissection (ESD) and can be achieved with various traction devices. Nevertheless, these devices have a fixed traction force that tends to decrease as the dissection progresses. In contrast, the ATRACT adaptive traction device increases traction during the procedure. METHODS : In this retrospective analysis of prospectively collected data (from a French database), we analyzed ESD procedures performed with the ATRACT device between April 2022 and October 2022. The device was used consecutively whenever possible. We collected details of lesion characteristics, procedural data, histologic outcomes, and clinical consequences for the patient. RESULTS : 54 resections performed in 52 patients by two experienced operators (46 procedures) and six novices (eight procedures) were analyzed. The ATRACT devices used were the ATRACT-2 (n = 21), the ATRACT 2 + 2 (n = 30), and the ATRACT-4 (n = 3). Four adverse events were observed: one perforation (1.9 %), which was closed endoscopically, and three delayed bleeding events (5.5 %). The R0 rate was 93 %, resulting in curative resection in 91 % of cases. CONCLUSION: ESD using the ATRACT device is safe and effective in the colon and rectum, but can also be used to assist with procedures in the upper gastrointestinal tract. It may be particularly useful in difficult locations.

Current Status of Diagnosis and Treatment of Colorectal Cancer in Asian Countries: A Questionnaire Survey.

INTRODUCTION: Diagnostic and therapeutic methods for colorectal cancer (CRC) have advanced; however, they may be inaccessible worldwide, and their widespread use is challenging. This questionnaire survey investigates the current status of diagnosis and treatment of early-stage CRC in Asian countries. METHODS: Responses to the questionnaire were obtained from 213 doctors at different institutions in 8 countries and regions. The questionnaire consisted of 39 questions on the following four topics: noninvasive diagnosis other than endoscopy (6 questions), diagnosis by magnification and image-enhanced endoscopy (IEE) including artificial intelligence (AI) (10 questions), endoscopic submucosal dissection (ESD), proper use among other therapeutic methods (11 questions), and pathologic diagnosis and surveillance (12 questions). RESULTS: Although 101 of 213 respondents were affiliated with academic hospitals, there were disparities among countries and regions in the dissemination of advanced technologies, such as IEE, AI, and ESD. The NICE classification is widely used for the diagnosis of colorectal tumors using IEE, while the JNET classification with magnification was used in countries such as Japan (65/70, 92.9%) and China (16/22, 72.7%). Of the 211 respondents, 208 (98.6%) assumed that en bloc resection should be achieved for carcinomas, and 180 of 212 (84.9%) believed that ESD was the most suitable in cases with a diameter larger than 2 cm. However, colorectal ESD is not widespread in countries such as Thailand, the Philippines, and Indonesia. CONCLUSION: The promotion of advanced technologies and education should be continual to enable more people to benefit from them.

Prevalence and clinical significance of the muscle retracting sign during endoscopic submucosal dissection of large macronodular colorectal lesions (with videos).

BACKGROUND AND AIMS: The muscle retracting sign (MRS) can be present during endoscopic submucosal dissection (ESD) of macronodular colorectal lesions. The prevalence of MRS and its pathologic and clinical implications is unclear. This study evaluated the effect of MRS on the technical and clinical outcomes of ESD. METHODS: All patients referred for ESD of protruding lesions or granular mixed lesions with >10 mm macronodule granular mixed laterally spreading tumors (LST-GMs) in 2 academic centers from January 2017 to October 2022 were prospectively included. Size of the macronodule was analyzed retrospectively. The primary outcome was the curative resection rate according to MRS status. Secondary outcomes were R0 resection, perforation, secondary surgery rate, and risk factors for MRS. RESULTS: Of 694 lesions, 84 (12%) had MRS (MRS+). The curative resection rate was decreased by MRS (MRS+ 41.6% vs lesions without MRS [MRS-] 81.3%), whereas the perforation (MRS+ 22.6% vs MRS- 9.2%), submucosal cancer (MRS+ 34.9% vs MRS- 9.2%), and surgery (MRS+ 45.2% vs MRS- 6%) rates were increased. The R0 resection rate of MRS+ colonic lesions was lower than that of rectal lesions (53% vs 74.3%). In multivariate analysis, protruding lesions (odds ratio, 2.47; 95% confidence interval, 1.27-4.80) and macronodules >4 cm (odds ratio, 4.24; 95% confidence interval, 2.23-8.05) were risk factors for MRS. CONCLUSIONS: MRS reduces oncologic outcomes and increases the perforation rate. Consequently, procedures in the colon should be stopped if MRS is detected, and those in the rectum should be continued due to the morbidity of alternative therapy.

The effect of subperichondrial dissection on nasal vascularity in septorhinoplasty operations.

PURPOSE: Nasal vascularization runs above the superficial musculoaponeurotic system (SMAS). Perichondrium covers the lower and upper lateral cartilages. In this study, nasal vascularization was compared between subperichondrial and supraperichondrial dissection in closed septorhinoplasty. METHODS: 95 patients and 41 volunteers were included in this study. Supraperichondrial dissection was performed in 48 patients and subperichondrial dissection was performed in 47 patients. To measure blood stream, laser doppler flowmetry (LDF) was used and measurements were done preoperatively, on the postoperative first week; 3rd month and first year. RESULTS: The nasal tip and dorsum measurements were similar between the preoperative and postoperative first year in both groups (p = 1.000). However, in the supraperichondrial dissection group, nasal tip measurements showed a significant increase between the preoperative and third postoperative months (p = 0.011). This increase was accompanied by an increase in the minimal blood stream (p = 0.014). CONCLUSION: Both subperichondrial and supraperichondrial dissection techniques are physiological and result in fewer complications with minimal permanent vascular damage. We believe incision plays a critical role but keeping the perichondrium intact is important for short-term angiogenesis, where long-term results showed no difference in vascularization.

Hybrid endoscopic submucosal dissection as a salvage option for difficult colorectal conventional endoscopic submucosal dissection.

BACKGROUND: When total submucosal dissection is difficult to achieve during conventional colorectal endoscopic submucosal dissection (C-ESD), the lesion can be resected by final snaring through salvage hybrid ESD (SH-ESD). This study aimed to examine the outcomes of SH-ESD and identify its indications that could achieve en bloc resection. METHODS: We recruited 1039 consecutive patients with colorectal lesions that underwent ESD at Hiroshima University Hospital between January 2015 and December 2020. C-ESD was attempted thoroughly in 924 lesions (C-ESD group, including 9 lesions in which ESD was discontinued), and SH-ESD was performed owing to some difficulties in 115 lesions (SH-ESD group). Risk factors for incomplete resection by SH-ESD and ESD discontinuation were evaluated using multivariate analysis. The outcomes were compared between cases with remaining undissected submucosa of < 20 mm in diameter in the SH-ESD and C-ESD groups, using propensity score matching. RESULTS: Multivariate analysis revealed that a procedure time > 80 min and remaining undissected submucosa ≥ 20 mm in diameter were significant risk factors for incomplete resection after SH-ESD and ESD discontinuation. By propensity score matching analysis, procedure time was significantly shorter in the SH-ESD group with remaining undissected submucosa < 20 mm in diameter than in the C-ESD group (71 min vs. 90 min, p = 0.0053), although no significant difference was found in the en bloc resection rate (94% vs. 87%, p = 0.0914). CONCLUSION: SH-ESD can be an alternative surgical method when conventional ESD is difficult to continue in cases in which the remaining undissected submucosa is < 20 mm in diameter.

Internal carotid artery dissection associated with acute dengue virus infection: a case report / Dissecção da artéria carótida interna associada à infecção aguda pelo vírus da dengue: relato de caso

Cervical artery dissections (CAD) can occur spontaneously or as a direct result of significant trauma. Viral infections, such as SARS-CoV2, influenza, and Epstein Barr, are risk factors for spontaneous CAD. Dengue virus infections have dramatically increased in recent decades, and Brazil is one of the endemic areas. The dengue virus can cause headache and neurological complications such as encephalitis, myelitis, Guillain-Barré syndrome, and myositis. No report has yet been found in the literature of dissection of the internal carotid artery secondary to dengue infection. Our objective is to report the case of a patient with dissection of the internal carotid artery associated with acute dengue virus infection.

As dissecções da artéria cervical (DAC) podem ocorrer espontaneamente ou como resultado direto de trauma significativo. Infecções virais, como SARS-CoV2, influenza e Epstein Barr, são fatores de risco para DAC espontânea. As infecções pelo vírus da dengue aumentaram dramaticamente nas últimas décadas, e o Brasil é uma das áreas endêmicas. O vírus da dengue pode causar dor de cabeça e complicações neurológicas como encefalite, mielite, síndrome de Guillain-Barré e miosite. Ainda não foi encontrado na literatura nenhum relato de dissecção da artéria carótida interna secundária à infecção por dengue. Nosso objetivo é relatar o caso de um paciente com dissecção da artéria carótida interna associada à infecção aguda pelo vírus da dengue.

Extracapsular dissection versus total excision for benign submandibular gland tumors.

INTRODUCTION: Benign submandibular gland tumors pose challenges in balancing treatment effectiveness and preserving gland function. This study aimed to compare gland-preserving surgery, extracapsular dissection (ECD), with total excision in managing these tumors, focusing on function preservation and recurrence rate. METHODS: Fifty consecutive patients with treatment-naïve benign submandibular gland tumors were alternatively allocated to receive ECD (n = 25) or total excision (n = 25) without randomization procedures. Intraoperative findings, postsurgical complications, subjective satisfaction, and gland function were assessed. Follow-up data were collected for a median duration of 55 months (24-80 months) to monitor recurrences. RESULTS: ECD demonstrated significant advantages, including shorter operation time, reduced bleeding, and preservation of the facial artery and vein (P < 0.05). Both groups exhibited acceptable postsurgical pain and taste sensations. Complications were minimal and similar between the two groups. ECD resulted in superior facial contour satisfaction (P = 0.030) and preserved gland function, as evidenced by salivary scintigraphy. No recurrences were observed in either group during the follow-up period. CONCLUSIONS: ECD is a practical approach for benign submandibular gland tumors, offering favorable functional outcomes, reduced surgical morbidity, shorter operation times, and improved cosmetic results.

Endoscopic intermuscular dissection (EID) for removing early rectal cancers and benign fibrotic rectal lesions.

In the current era of screening colonoscopy and increasing incidence of early rectal cancer, interventional endoscopy moves toward resections in deeper planes than the submucosal layer. Several reports support the use of endoscopic intermuscular dissection (EID) instead of endoscopic submucosal dissection (ESD) for the removal of deeply invasive rectal submucosal cancers. The resection plane into the intermuscular space, the space between the longitudinal (external) and circular (internal) muscle layer, allows radical removal of rectal invasive submucosal cancers. Furthermore, the technique offers the potential for dissection of scarred and severe fibrotic lesions in the rectum by cutting deeper and performing a partial myectomy avoiding the narrow submucosal space. We present 23 cases of EIDs both for deeply invasive rectal cancers and benign rectal lesions. This is the first report in the literature of EID resections for malignant and benign disease, including cases of severely fibrotic rectal lesions.

Is colorectal endoscopic submucosal dissection safe and effective for 15-19-mm tumors?

PURPOSE: The outcomes of colorectal endoscopic submucosal dissection (ESD) in 15-19-mm tumors are unclear. This study compared the effectiveness and safety of colorectal ESD for 15-19-mm tumors and tumors exceeding that size. METHODS: From August 2018 to December 2020, 213 cases of colorectal tumors removed by colorectal ESD at a tertiary hospital were enrolled in this study. The cases were divided into two groups according to the pathologically measured size of the resected lesion: an intermediate group (15-19 mm, n = 62) and a large group (≥ 20 mm, n = 151). The en bloc resection rate, complete resection rate, and complications were investigated retrospectively. RESULTS: The en bloc resection rate was significantly higher in the intermediate than large group (100% vs. 94%, p = 0.049), and the mean total procedure time was shorter in the intermediate than large group (29.2 [Formula: see text] 12.6 vs. 48.4 [Formula: see text] 28.8 min, p < 0.001). However, the mean procedure speed was significantly lower in the intermediate than large group (0.25 [Formula: see text] 0.10 vs. 0.28 [Formula: see text] 0.11 cm2/min, p = 0.031). The complete resection rate, post-procedural bleeding, and perforation rate were not significantly different between the two groups. In multivariate analyses, the total procedure time and mean procedure speed were significantly associated with lesion size. CONCLUSION: Colorectal ESD of 15-19-mm lesions is effective, and has a shorter procedure time and higher en bloc resection rate than the same procedure for larger lesions.

Inframesocolic main pancreatic vessels-first approach for minimally invasive radical antegrade modular pancreaticosplenectomy (RAMPS): technical description and first experience.

Radical modular antegrade pancreaticosplenectomy (RAMPS) improves posterior tumor-free margins during resections of pancreatic neoplasia involving the body or tail. However, minimally invasive RAMPS is technically challenging and has been reported seldom. We present for the first time a minimally invasive RAMPS technique with an innovative approach providing early dissection and control of the main peripancreatic vessels from an inframesocolic embryonal window, suitable for laparoscopy and robotics. Minimally invasive RAMPS with inframesocolic main pancreatic vessels-first approach was performed at the Tricase Hospital (Italy) from May 2017 to April 2022 in 11 consecutive patients with neoplastic lesions of the pancreas (8 laparoscopic RAMPS and 3 robotic RAMPS). Among the laparoscopic cases, 1 included a portal vein tangential resection and 1 a celiac artery resection (modified Appleby procedure). There were no conversions, no Clavien-Dindo complications > 2, all resections' margins were tumor free, and no 90-day mortality.