Falciform technique in laparoscopic revision of distal catheter obstruction: an evaluation.

Background: Ventriculoperitoneal (VP) shunting is a cornerstone treatment for hydrocephalus, a condition characterized by the abnormal accumulation of cerebrospinal fluid in the ventricles of the brain. Despite its efficacy, this procedure is associated with various complications, among which distal catheter obstruction poses significant challenges. This study aimed to evaluate the effectiveness of the 'falciform technique' in laparoscopic revision of distal catheter obstructions, offering a novel approach to mitigate this prevalent issue. Materials and methods: This study retrospectively analyzed 28 patients with VP shunt distal catheter obstructions who underwent laparoscopy-assisted shunt revision between January 2016 and June 2022. All of these were done using the 'falciform technique' with the fixation of the distal catheter to the falciform ligament in supra-hepatic space. Results: The most common etiology of primary shunt surgery was hydrocephalus, followed by intracranial hemorrhage (42.9%) and traumatic brain injury (32.1%). Normal pressure hydrocephalus occurs in 14.3% of cases. Fifteen patients (53.6%) required revision surgery within 1 year of index surgery. Thirteen patients (46.4%) underwent revision surgery more than 1 year after the index surgery, either as a first revision or subsequent revision. The average surgery time was 32.1±14.7 min and hospital stay was 4.2±1.8 days. After a mean follow-up period of at 20.3±8.7 months, except for three patients who died from other causes (two patients due to pneumonia and one due to exhaustion), there were no shunt-related complications in the remaining 25 patients. Conclusions: Laparoscopy with the application of 'falciform technique' is a safe and highly effective method in distal catheter obstruction revision following VP shunt.

Retrosternal herniation of transverse colon following minimal invasive esophagectomy causing dysphagia: A case report.

INTRODUCTION AND IMPORTANCE: Minimally invasive esophagectomy has emerged as the established standard for treating esophageal cancer. The gastric graft is usually placed in the posterior mediastinum or the retrosternal tunnel for reconstruction. Hiatal hernia occurrence is more common in the posterior mediastinal reconstruction and is more frequently observed in laparoscopic compared to open approach. On the other hand, retrosternal hernia is a rare complication that deserves greater attention, considering the increasing popularity of retrosternal reconstruction in esophageal cancer treatment. CASE PRESENTATION: We present the case of a 55-year-old male patient who underwent minimally invasive esophagectomy with retrosternal reconstruction using gastric conduit and cervical anastomosis. After four years, the patient experienced symptoms, including dyspnea and chest pain. CT scan revealed transverse colon herniation into the retrosternal tunnel. CLINICAL DISCUSSION: Our diagnosis was retrosternal herniation of the transverse colon. Although there was no sign of obstruction, the abundant colon in the retrosternal space caused mass effect symptoms. For that reason, we performed laparoscopic surgery to release the herniated organ and close the hernia hole. Postoperatively, the patient had a satisfactory recovery, and a follow-up CT scan confirmed the absence of any remaining herniated organs. CONCLUSION: While hiatal hernia is a well-known complication in minimally invasive esophagectomy, retrosternal hernia is a lesser-known entity. Surgical intervention is necessary to alleviate symptoms caused by herniation or address complications such as strangulation. The occurrence of retrosternal hernia warrants further attention and research in the future.

Intrathoracic herniation of retrosternal gastric conduit after thoracolaparoscopic esophagectomy causing gastric conduit obstruction: A case report.

INTRODUCTION AND IMPORTANCE: Intrathoracic herniation of gastric conduit (IHGC) is a specific complication following esophagectomy with retrosternal gastric pull-up but is not well recognized. Diagnosis and management are challenging due to the lack of literature reviews. CASE PRESENTATION: We report a 50-year-old man where a reconstructed gastric conduit hernia into the mediastinal pleural cavity after esophagectomy. The patient underwent minimally invasive esophagectomy with cervical anastomosis for middle esophageal carcinoma followed by retrosternal reconstruction; during the tunneling phase, the mediastinal pleura was injured. Subsequently, the patient developed progressive dysphagia postoperatively, and chest CT scans revealed that the dilating gastric tube had moved into the mediastinal pleural cavity. CLINICAL DISCUSSION: After ruling out the pyloric stenosis by endoscopy, our diagnosis was severe gastric outlet obstruction due to gastric conduit herniation. We performed laparoscopic surgery to mobilize and straighten the redundant gastric conduit. No recurrence occurred throughout the follow-up for one year. CONCLUSION: IHGC can cause gastric conduit obstruction, which requires reoperation to repair. The laparoscopic approach is an appropriate strategy with the advantages of being less invasive and effective in mobilizing and straightening the gastric conduit. To prevent mediastinal pleural injury - which affects the continuation of the reconstructions, the surgeon should use blunt dissection with direct observation during the route creation.

Ultra-widefield photoacoustic microscopy with a dual-channel slider-crank laser-scanning apparatus for in vivo biomedical study.

Photoacoustic microscopy (PAM) is an important imaging tool that can noninvasively visualize the anatomical structure of living animals. However, the limited scanning area restricts traditional PAM systems for scanning a large animal. Here, we firstly report a dual-channel PAM system based on a custom-made slider-crank scanner. This novel scanner allows us to stably capture an ultra-widefield scanning area of 24 mm at a high B-scan speed of 32 Hz while maintaining a high signal-to-noise ratio. Our system's spatial resolution is measured at ∼3.4 µm and ∼37 µm for lateral and axial resolution, respectively. Without any contrast agent, a dragonfly wing, a nude mouse ear, an entire rat ear, and a portion of mouse sagittal are successfully imaged. Furthermore, for hemodynamic monitoring, the mimicking circulating tumor cells using magnetic contrast agent is rapidly captured in vitro. The experimental results demonstrated that our device is a promising tool for biological applications.

Improved Depth-of-Field Photoacoustic Microscopy with a Multifocal Point Transducer for Biomedical Imaging.

In this study, a photoacoustic microscopy (PAM) system based on a multifocal point (MFP) transducer was fabricated to produce a large depth-of-field tissue image. The customized MFP transducer has seven focal points, distributed along with the transducer's axis, fabricated by separate spherically-focused surfaces. These surfaces generate distinct focal zones that are overlapped to extend the depth-of-field. This design allows extending the focal zone of 10 mm for the 11 MHz MFP transducer, which is a great improvement over the 0.48 mm focal zone of the 11 MHz single focal point (SFP) transducer. The PAM image penetration depths of a chicken-hemoglobin phantom using SFP and MFP transducers were measured as 5 mm and 8 mm, respectively. The significant increase in the PAM image-based penetration depth of the chicken-hemoglobin phantom was a result of using the customized MFP transducer.

Design, Fabrication, and Evaluation of Multifocal Point Transducer for High-Frequency Ultrasound Applications.

The present study illustrates the design, fabrication, and evaluation of a novel multifocal point (MFP) transducer based on polyvinylidene fluoride (PVDF) film for high-frequency ultrasound application. The fabricated MFP surface was press-focused using a computer numerical control (CNC) machining tool-customized multi-spherical pattern object. The multi-spherical pattern has five spherical surfaces with equal area and connected continuously to have the same energy level at focal points. Center points of these spheres are distributed in a linear pattern with 1 mm distance between each two points. The radius of these spheres increases steadily from 10 mm to 13.86 mm. The designed MFP transducer had a center frequency of 50 MHz and a -6 dB bandwidth of 68%. The wire phantom test was conducted to study and demonstrate the advantages of this novel design. The obtained results for MFP transducer revealed a significant increase (4.3 mm) of total focal zone in the near-field and far-field area compared with 0.48 mm obtained using the conventional single focal point transducer. Hence, the proposed method is promising to fabricate MFP transducers for deeper imaging depth applications.