A review of functional neuromodulation in humans using low-intensity transcranial focused ultrasound.

Transcranial ultrasonic neuromodulation is a rapidly burgeoning field where low-intensity transcranial focused ultrasound (tFUS), with exquisite spatial resolution and deep tissue penetration, is used to non-invasively activate or suppress neural activity in specific brain regions. Over the past decade, there has been a rapid increase of tFUS neuromodulation studies in healthy humans and subjects with central nervous system (CNS) disease conditions, including a recent surge of clinical investigations in patients. This narrative review summarized the findings of human neuromodulation studies using either tFUS or unfocused transcranial ultrasound (TUS) reported from 2013 to 2023. The studies were categorized into two separate sections: healthy human research and clinical studies. A total of 42 healthy human investigations were reviewed as grouped by targeted brain regions, including various cortical, subcortical, and deep brain areas including the thalamus. For clinical research, a total of 22 articles were reviewed for each studied CNS disease condition, including chronic pain, disorder of consciousness, Alzheimer's disease, Parkinson's disease, depression, schizophrenia, anxiety disorders, substance use disorder, drug-resistant epilepsy, and stroke. Detailed information on subjects/cohorts, target brain regions, sonication parameters, outcome readouts, and stimulatory efficacies were tabulated for each study. In later sections, considerations for planning tFUS neuromodulation in humans were also concisely discussed. With an excellent safety profile to date, the rapid growth of human tFUS research underscores the increasing interest and recognition of its significant potential in the field of non-invasive brain stimulation (NIBS), offering theranostic potential for neurological and psychiatric disease conditions and neuroscientific tools for functional brain mapping.

A review of algorithms and software for real-time electric field modeling techniques for transcranial magnetic stimulation.

Transcranial magnetic stimulation (TMS) is a device-based neuromodulation technique increasingly used to treat brain diseases. Electric field (E-field) modeling is an important technique in several TMS clinical applications, including the precision stimulation of brain targets with accurate stimulation density for the treatment of mental disorders and the localization of brain function areas for neurosurgical planning. Classical methods for E-field modeling usually take a long computation time. Fast algorithms are usually developed with significantly lower spatial resolutions that reduce the prediction accuracy and limit their usage in real-time or near real-time TMS applications. This review paper discusses several modern algorithms for real-time or near real-time TMS E-field modeling and their advantages and limitations. The reviewed methods include techniques such as basis representation techniques and deep neural-network-based methods. This paper also provides a review of software tools that can integrate E-field modeling with navigated TMS, including a recent software for real-time navigated E-field mapping based on deep neural-network models.

The association between the severity of erectile dysfunction and left ventricular diastolic dysfunction in patients with and without cardiovascular disease.

PURPOSE: Erectile dysfunction (ED) is considered a microvascular disorder and serves as an indicator for the potential development of cardiovascular disease (CVD). Although left ventricular diastolic dysfunction (LVDD) reflects early myocardial damage caused by microvascular disorders, the association between ED and LVDD remains poorly elucidated. MATERIALS AND METHODS: A cross-sectional study was conducted on 123 patients with ED. They underwent RigiScan, and conventional echocardiography, and attempted International Index of Erectile Function (IIEF) questionnaire. ED severity was evaluated by measuring changes in the penile base circumference and duration of penile rigidity (≥70%) during erection. The early diastolic velocity of mitral inflow (E) and early diastolic velocity of the mitral annulus (e') were measured using echocardiography. The patients were grouped based on the presence of CVD. RESULTS: Among 123 patients, 29 had CVD and 94 did not. Patients with CVD exhibited more pronounced ED and more severe LVDD. Associations between increased penile circumference with echocardiographic parameters were more prominent in patients with CVD than in those without CVD (ΔTtop and e' wave, r=0.508 and r=0.282, respectively, p for interaction=0.033; ΔTbase and E/e' ratio, r=-0.338 and r=-0.293, respectively, p for interaction <0.001). In the multivariate linear regression, the increase of penile base circumference was an independent risk factor for LVDD (e', B=0.503; E/e' ratio, B=-1.416, respectively, p<0.001). CONCLUSIONS: ED severity correlated well with LV diastolic dysfunction, particularly in the presence of CVD. This study highlighted the potential role of ED assessment as early indicator of CVD development.

Sex Differences in Heart Rate Variability and Vascular Function Following High-Intensity Interval Training in Young Adults.

High-intensityintervaltraining (HIIT) issuperiortoothertrainingstrategies in both male andfemalehealthyindividuals. Understanding sex-specificdifferences in cardiac auto-regulation maycontributetothe optimal trainingstrategiesfor HIIT. The presentstudyaimedtoidentifysexdifferences in heart rate variability (HRV) andvascularfunctionfollowing HIIT in youngadults. Twenty-fourphysicallyactiveyoung male andfemaleadults (M: 12, F: 12, age: 19.5 yr, BMI: 22.1 kg·m-2) volunteeredtoparticipate in thestudy. Participantsperformed 10 boutsof HIIT including 20 s of high-intensitycycling at 115-130% Wmaxfollowedby 100 s ofrecovery. The cardiac auto-regulationsincluding HRV andvascularfunctionweremeasured at five different time points. The R-R interval, rMSSD, and SDNN wererecoveredfaster in malesthan in females after 15 min of HIIT. Thereweresexdifferences in theautonomicnervoussystemwhereln LF andln HF activitiesalongwithsympathovagalbalance (ln LF/HF) weregreater in femalescomparedwithmalesimmediatelyand 15 min after HIIT. However, nosignificantdifferences in bloodpressureand brachial-ankle pulse wavevelocitywereobservedbetween male andfemaleparticipants. Overall, HRV was moreactivated in femalesthan in malesfollowing HIIT, but theacuteresponse in vascularfunction was not different betweensexes. In futurestudies, sex-specificadaptationsofcardiacautoregulationfollowingrepeated HIIT mayneedtobeperformed.

SlicerTMS: Real-Time Visualization of Transcranial Magnetic Stimulation for Mental Health Treatment.

We present a real-time visualization system for Transcranial Magnetic Stimulation (TMS), a non-invasive neuromodulation technique for treating various brain disorders and mental health diseases. Our solution targets the current challenges of slow and labor-intensive practices in treatment planning. Integrating Deep Learning (DL), our system rapidly predicts electric field (E-field) distributions in 0.2 seconds for precise and effective brain stimulation. The core advancement lies in our tool's real-time neuronavigation visualization capabilities, which support clinicians in making more informed decisions quickly and effectively. We assess our system's performance through three studies: First, a real-world use case scenario in a clinical setting, providing concrete feedback on applicability and usability in a practical environment. Second, a comparative analysis with another TMS tool focusing on computational efficiency across various hardware platforms. Lastly, we conducted an expert user study to measure usability and influence in optimizing TMS treatment planning. The system is openly available for community use and further development on GitHub: https://github.com/lorifranke/SlicerTMS.

Real-Time Acoustic Simulation Framework for tFUS: A Feasibility Study Using Navigation System.

Transcranial focused ultrasound (tFUS), in which acoustic energy is focused on a small region in the brain through the skull, is a non-invasive therapeutic method with high spatial resolution and depth penetration. Image-guided navigation has been widely utilized to visualize the location of acoustic focus in the cranial cavity. However, this system is often inaccurate because of the significant aberrations caused by the skull. Therefore, acoustic simulations using a numerical solver have been widely adopted to compensate for this inaccuracy. Although the simulation can predict the intracranial acoustic pressure field, real-time application during tFUS treatment is almost impossible due to the high computational cost. In this study, we propose a neural network-based real-time acoustic simulation framework and test its feasibility by implementing a simulation-guided navigation (SGN) system. Real-time acoustic simulation is performed using a 3D conditional generative adversarial network (3D-cGAN) model featuring residual blocks and multiple loss functions. This network was trained by the conventional numerical acoustic simulation program (i.e., k-Wave). The SGN system is then implemented by integrating real-time acoustic simulation with a conventional image-guided navigation system. The proposed system can provide simulation results with a frame rate of 5 Hz (i.e., about 0.2 s), including all processing times. In numerical validation (3D-cGAN vs. k-Wave), the average peak intracranial pressure error was 6.8 ± 5.5%, and the average acoustic focus position error was 5.3 ± 7.7 mm. In experimental validation using a skull phantom (3D-cGAN vs. actual measurement), the average peak intracranial pressure error was 4.5%, and the average acoustic focus position error was 6.6 mm. These results demonstrate that the SGN system can predict the intracranial acoustic field according to transducer placement in real-time.

Relationship between the Tokyo Guidelines and Pathological Severity in Acute Cholecystitis.

Background: It is not well understood whether the severity of acute cholecystitis (AC) correlates with the extent of gallbladder (GB) inflammation or laboratory findings. This study aimed to assess whether the severity of AC, in accordance with the Tokyo Guidelines (TGs), is consistent with the extent of GB inflammation on histopathological and laboratory findings, including microbiological isolation in blood and bile. Methods: The medical records of patients who underwent cholecystectomy for AC between January 2017 and May 2020 were reviewed. Demographic data, laboratory findings, the microbiologic culture of blood and bile, the extent of GB inflammation, and stone composition were compared in accordance with the TGs. Results: A total of 217 patients were divided into three groups of increasing severity-Grade I (n = 146), Grade II (n = 51), and Grade III (n = 20)-in accordance with the TGs. The Grade III group contained significantly older patients compared with the Grade I or Grade II groups (Grade I, 56.9 ± 13.9; Grade II, 64.3 ± 15.4; Grade III, 69.9 ± 9.9; p-value < 0.001). Patients in the Grade III group showed significantly higher levels of CRP, WBC, creatinine, and bilirubin and lower levels of platelets and albumin compared with the Grade I or Grade II group. As the grade of severity increased, the rate of microbiological isolation in blood (Grade I, 0% [0/146]; Grade II, 2.0% [1/51]; Grade III, 20% [4/20]; p-value < 0.001) and bile (Grade I, 19.9% [29/146]; Grade II, 33.3% [17/51]; Grade III, 70% [14/20]; p-value < 0.001) also increased significantly. However, there were no significant differences in the extent of GB inflammation between grades. Conclusions: AC severity, as stated by the TGs, does not correlate with the extent of GB inflammation on histopathological and laboratory findings. However, microbiological isolation in blood and bile was increased proportionally to the grade of the TGs.

Aggressive hydration for preventing post-endoscopic retrograde cholangiopancreatography pancreatitis: trial sequential analysis.

BACKGROUND: Randomized controlled trials (RCTs) have demonstrated that aggressive hydration with lactated Ringer's (LR) solution reduces the frequency and severity of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). In this trial sequential analysis (TSA), we aimed to evaluate the prophylactic effect of aggressive hydration on PEP in specific patient subgroups and to determine the need for additional RCTs. METHODS: We conducted a systematic and comprehensive search to identify all randomized controlled studies published through August 2021 that examined the effectiveness of aggressive hydration for preventing PEP. The primary outcome was the frequency of PEP. We also performed TSA to calculate the required information size and assess whether our results were conclusive. RESULTS: The analysis included 12 studies involving 2,501 patients. According to the TSA, the overall frequency of PEP was significantly lower in the aggressive hydration group (5.6%; 74 of 1,327 patients) than in the control group (13.1%; 154 of 1,174 patients) (risk ratio [RR]: 0.458; 95% confidence interval [CI]: 0.350-0.599). In the subgroup analysis of patients with average risk, the cumulative Z curve crossed both the conventional test boundary and the trial sequential monitoring boundary. However, in the high-risk group and in patients with moderate-to-severe PEP, the Z curve did not cross the trial sequential monitoring boundary. CONCLUSIONS: This TSA indicates that aggressive hydration is effective in the overall prevention of PEP. However, additional RCTs are required to examine the prophylactic effect of aggressive hydration with LR on PEP in high-risk populations.

Outcomes of Endoscopic Retrograde Cholangiopancreatography in End-Stage Renal Disease Patients Undergoing Hemodialysis: A Systematic Review and Pooled Analysis.

Background/Aims: The adverse events associated with endoscopic retrograde cholangiopancreatography (ERCP) in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) have not been sufficiently evaluated. This study aimed to review the morbidity and mortality associated with ERCP in ESRD patients on HD using a systematic review and pooled analysis. Methods: A systematic review and pooled analysis were conducted on studies that evaluated the clinical outcomes of ERCP in patients on HD. Random-effect model meta-analyses with subgroup analyses were conducted. The methodological quality of the included publications was evaluated using the risk of bias assessment tool for nonrandomized studies. The publication bias was assessed. Results: A total of 239 studies were identified, and 12 studies comprising 7921 HD patients were included in the analysis. The pooled estimated frequency of bleeding associated with ERCP in HD patients was 5.8% (460/7921). In the subgroup analysis of seven comparative studies, the ERCP-related bleeding rate was significantly higher in HD patients than in non-HD patients (5.5% (414/7544) vs. 1.5% (6734/456,833), OR 3.84; 95% CI 4.26−25.5; p < 0.001). The pooled frequency of post-ERCP pancreatitis was 8.3%. The pooled frequency of bowel perforation was 0.3%. The pooled estimated mortality associated with ERCP was 7.1% The publication bias was minimal. Conclusion: This pooled analysis showed that ERCP-related morbidity and mortality are higher in HD patients than in non-dialysis patients.

Persistent Trigeminal Artery Variant Terminating in the Ipsilateral Superior Cerebellar Artery.

Persistent trigeminal artery (PTA) represent an unusual remnant of the fetal carotid-basilar anastomosis. Persistent trigeminal artery variant (PTAV) is a rare anastomosis between the internal carotid artery and cerebellar artery, without an interposing basilar artery segment. We report the case of 49-year-old female with an incidentally discovered, rare variation of PTA that directly terminated in the ipsilateral superior cerebellar artery. The variation was observed on CT angiography, digital subtraction angiography, and MR angiography. Additionally, we reviewed the embryogenesis of PTA and PTAV and discussed the clinical implications of this variation.

Rib and pericardium invaded huge abdominal mass in young woman: A case report with literature review.

RATIONALE: Desmoid fibromatosis is a rare benign tumor, but due to its rarity and diverse clinical course, treatment guidelines have not been established. However, since a good prognosis can be expected, an accurate diagnosis and appropriate treatment are required. We describe a rare case of desmoid fibromatosis on young female that presented as huge abdominal mass. PATIENTS CONCERNS: A 28-year-old female with left upper abdominal pain 1 month ago was referred. DIAGNOSES: Abdominal computed tomography and magnetic resonance imaging revealed a heterogeneous soft tissue mass approximately 29 × 17 cm in size in the left abdomen with abdominal wall invasion and pathological fracture in costochondral junction of the left 8th to 10th ribs. INTERVENTIONS: Surgical resection was performed. OUTCOMES: 33 × 23 × 6 cm sized tumorous mass showed proliferation of bland fibromatosis and myofibroblast with nuclear ß-catenin expression on pathological examination. Desmoid fibromatosis arising from intra-abdominal soft tissue with ribs and pericardium invasion was diagnosed. LESSONS: The mainstay of treatment of symptomatic desmoid fibromatosis is surgical resection, and in the case of abdominal tumor, it can be more dangerous when it invades adjacent organ. We report a case that required additionally multidisciplinary approach for surgery and postoperative treatment of huge abdominal desmoid tumor which infiltrate bone and pericardium beyond abdominal cavity.

Application of subject-specific helmets for the study of human visuomotor behavior using transcranial focused ultrasound: a pilot study.

BACKGROUND AND OBJECTIVE: As a novel non-invasive human brain stimulation method, transcranial focused ultrasound (tFUS) is receiving growing attention due to its superior spatial specificity and depth penetrability. Since the focal point of tFUS needs to be fixated precisely to the target brain region during stimulation, a critical issue is to identify and maintain the accurate position and orientation of the tFUS transducer relative to the subject's head. This study aims to propose the entire framework of tFUS stimulation integrating the methods previously proposed by the authors for tFUS transducer configuration optimization and a subject-specific 3D-printed helmet, and to validate this complete setup in a human behavioral neuromodulation study. METHODS: To find the optimal configuration of the tFUS transducer, a numerical method based on subject-specific tFUS beamlines simulation was used. Then, the subject-specific 3D-printed helmet has been applied to effectively secure the transducer at the estimated optimal configuration. To validate this tFUS framework, a common behavioral neuromodulation paradigm was chosen; the effect of the dorsolateral prefrontal cortex (DLPFC) stimulation on anti-saccade (AS) behavior. While human participants (n=2) were performing AS tasks, tFUS stimulations were randomly applied to the left DLPFC right after the fixation target disappeared. RESULTS: The neuromodulation result strongly suggests that the cortical stimulation using the proposed tFUS setup is effective in significantly reducing the error rates of anti-saccades (about -10 %p for S1 and -16 %p for S2), whereas no significant effect was observed on their latencies. These observed behavioral effects are consistent with the previous results based on conventional brain stimulation or lesion studies. CONCLUSIONS: The proposed subject-specific tFUS framework has been effectively used in human neuromodulation study. The result suggests that the tFUS stimulation targeted to the DLPFC can generate a neuromodulatory effect on AS behavior.

Differential evolution method to find optimal location of a single-element transducer for transcranial focused ultrasound therapy.

BACKGROUND AND OBJECTIVE: Focused ultrasound (FUS) has been receiving growing attention as a noninvasive brain stimulation tool because of its superior spatial specificity and depth penetrability. However, the large mismatch of acoustic properties between the skull and water can disrupt and shift the acoustic focus in the brain. In this paper, we present a numerical method to find the optimal location of a single-element FUS transducer, which creates focus on the target region. METHODS: The score function, representing the superposition of acoustic waves according to the relative phase difference and transmissibility, was defined based on time-reversal invariance of acoustic waves and depending on the spatial location of the transducer. The optimal location of the transducer was then determined using a differential evolution algorithm. To assess the proposed method, we conducted a forward simulation and compared the resulting focal location to the desired target point. We also performed experimental validation by measuring the acoustic pressure field through an ex vivo human skull in a water tank. RESULTS: The numerical results indicated that the score function had a positive proportional relationship with the acoustic pressure at the target. Moreover, for the optimized transducer location, both the numerical and experimental results showed that the normalized acoustic pressure at the target was higher than 0.9. CONCLUSIONS: In this study, we developed an optimization method to place a single-element transducer that effectively transmits acoustic energy to the targeted region in the brain. Our numerical and experimental results demonstrate that the proposed method can provide an optimal transducer location for safe and efficient FUS treatment.

Outcome of Endoscopic Ultrasound-Guided Sampling of Mediastinal Lymphadenopathy.

Methods: From May 2006 to January 2017, patients with mediastinal lymphadenopathy, who received an EUS-guided trucut biopsy or an FNA biopsy, were retrospectively reviewed. Demographic data, endosonographic characteristics of LNs including size, shape, border, echotexture, and echogenicity, diagnostic yield, and adverse events between the trucut needle group and aspiration needle group were compared. Results: A total of 69 patients (trucut group, n = 33 vs. aspiration group, n = 36) were identified. There were no significant differences in demographic data, indication for an EUS-guided biopsy, location of LNs, number of needle passes, and endosonographic features of LNs between the two groups. The sizes of LNs were larger in the trucut group than in the aspiration group (28.9 ± 14.0 mm vs. 21.1 ± 8.8 mm, P = 0.007). However, there was no significant difference in the ratio of LNs that were ≥10 mm in both groups. The overall accuracy of the EUS-guided biopsy for the diagnosis of malignant lesions was 79.7% (55/69). There were no significant differences in the histological diagnostic yield of malignant LNs between the two groups. There were no significant procedure-related adverse events in both groups. Conclusion: The EUS-guided biopsy can be a useful method for histologic evaluation of mediastinal nodal lesions.

Effect of prophylactic endoscopic clipping for prevention of delayed bleeding after endoscopic papillectomy for ampullary neoplasm: a multicenter randomized trial.

BACKGROUND : Endoscopic clip placement is technically challenging using a duodenoscope, limiting their application for treatment of bleeding after endoscopic papillectomy. This study evaluated the efficacy of newly designed clips to prevent bleeding after endoscopic papillectomy. METHODS : Patients (n = 80) with suspected benign adenomas on the major papilla who were scheduled for endoscopic papillectomy with or without clipping were randomized. A new duodenoscope-compatible clip capable of being rotated, reopened, and repeatedly repositioned was used. The primary end point was incidence of delayed bleeding. RESULTS : The clipping procedure was successful in all patients. The incidence of delayed bleeding was nonsignificantly higher in the no-clipping group than in the clipping group (31.6 % [95 % confidence interval (CI) 19.1-47.5] vs. 15.0 % [95 %CI 7.1-29.1]). The incidence of post-endoscopic retrograde cholangiopancreatography pancreatitis did not differ significantly between the groups (clipping vs. no-clipping: 17.5 % [95 %CI 8.7-31.9] vs. 5.3 % [95 %CI 1.5-17.3]), and all cases were mild. CONCLUSIONS : Placement of the newly designed rotatable clip was technically feasible and tended to have a protective effect by preventing delayed bleeding after endoscopic papillectomy, although statistical significance was not reached.

Rectal NSAIDs-based combination modalities are superior to single modalities for prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis: a network meta-analysis.

BACKGROUND/AIMS: Different modalities have been employed to reduce the risk and severity of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). However, there has been a paucity of studies comparing the efficacy of various prophylactic modalities for preventing PEP. This network meta-analysis (NMA) aimed to determine the relative efficacy of pancreatic duct stents and pharmacological modalities for preventing PEP. METHODS: We performed a systematic and comprehensive search to identify and analyze all randomized controlled studies published until June 2020 that examined the effectiveness of pancreatic duct stents, rectal non-steroidal anti-inflammatory drugs (NSAIDs) based regimens, hydration, and their combinations for the prevention of PEP. The primary outcome was the frequency of PEP. An NMA was performed to combine direct and indirect comparisons of different prophylactic modalities. RESULTS: The NMA included 46 studies evaluating 18 regimens in 16,241 patients. Based on integral analysis of predictive interval plots, and expected mean ranking and surface under the cumulative ranking curve values, combination prophylaxis with indomethacin + lactated Ringer's solution (LR), followed by diclofenac + nitrate and indomethacin + normal saline, was found to be the most efficacious modality for the overall prevention of PEP. Indomethacin + LR, followed by diclofenac and pancreatic duct stents, was the most efficacious modality for high-risk groups. CONCLUSION: Rectal NSAIDs-based combination regimens with aggressive hydration or nitrate are superior to single modalities for the prevention of PEP.

Enteritis cystica profunda with lipoma in the second portion of the duodenum: a case report.

Enteritis cystica profunda (ECP), a rare and benign condition, is defined as the displacement of the glandular epithelium into the submucosa and more profound layers of the small intestinal wall leading to the formation of mucin-filled cystic spaces. ECP frequently occurs in the ileum or jejunum and is associated with diseases such as Crohn disease and Peutz-Jeghers syndrome. ECP also develops in the absence of known pathology. ECP in the duodenum is very rare and mostly occurs without associated conditions. In this report, we present a rare case of ECP without an associated disease, in the second portion of the duodenum distal to the ampulla of Vater and coexisting with lipoma within the polypoid lesion.

Acoustic Simulation for Transcranial Focused Ultrasound Using GAN-Based Synthetic CT.

Transcranial focused ultrasound (tFUS) is a promising non-invasive technique for treating neurological and psychiatric disorders. One of the challenges for tFUS is the disruption of wave propagation through the skull. Consequently, despite the risks associated with exposure to ionizing radiation, computed tomography (CT) is required to estimate the acoustic transmission through the skull. This study aims to generate synthetic CT (sCT) from T1-weighted magnetic resonance imaging (MRI) and investigate its applicability to tFUS acoustic simulation. We trained a 3D conditional generative adversarial network (3D-cGAN) with 15 subjects. We then assessed image quality with 15 test subjects: mean absolute error (MAE) = 85.72±9.50 HU (head) and 280.25±24.02 HU (skull), dice coefficient similarity (DSC) = 0.88±0.02 (skull). In terms of skull density ratio (SDR) and skull thickness (ST), no significant difference was found between sCT and real CT (rCT). When the acoustic simulation results of rCT and sCT were compared, the intracranial peak acoustic pressure ratio was found to be less than 4%, and the distance between focal points less than 1 mm.

Colonic diverticular perforation by a migrated biliary stent: A case report with literature review.

RATIONALE: Plastic endobiliary stents, after endoscopic retrograde cholangiopancreatography, can get spontaneously dislocated from the common bile duct and migrate intothe distal bowel. Most migrated biliary stents are removed with the passing of stool. However, migrated biliary stents can cause bowel perforation, albeit rarely, and surgical intervention may be required. Recently, we observed a colonic diverticular perforation caused by a migrated biliary stent, and we have reported this case with a review of the literature. PATIENTS CONCERNS: A 74-year-old man presented with severe right lower quadrant pain after biliary stent insertion 1month ago. DIAGNOSES: Abdominal computed tomography revealed perforation of the proximal ascending colon by the migrated biliary stent, combined with localized peritonitis. INTERVENTIONS: Emergency diagnostic laparoscopic examination revealed penetration of the proximal ascending colon by the plastic biliary stent, and right hemicolectomy was performed. OUTCOMES: On pathological examination, colonic diverticular perforation by the biliary stent was confirmed. The patient was discharged without any additional complications. LESSONS: Endoscopic retrograde cholangiopancreatography endoscopists must always be cautious of the possibility of stent migration in patients with biliary stents in situ. In cases of biliary stent dislocation from the common bile duct in asymptomatic patients, follow-up with serial, plain abdominal radiographs, and physical examination is needed until confirmation of spontaneous passage through stool. In symptomatic cases suggesting peritonitis, abdominal computed tomography scan confirmation is needed, and early intervention should be considered.

Successful Medical Treatment for Peritonitis Resulting from a Large Pyogenic Liver Abscess Rupture.

The rupture of a pyogenic liver abscess (PLA) with peritonitis is a rare occurrence but a surgical emergency with a high mortality rate in the case of gas-forming PLA. Rare cases of ruptured PLA that recovered completely with only medical treatment have been reported. This paper reports a case of a large PLA rupture with peritonitis. In this case, surgical intervention was too risky because of the patient's age and poor general condition. The patient recovered fully with appropriate antibiotic therapy and sufficient percutaneous drainage. Therefore, medical treatment may be considered an alternative option in cases of a ruptured large PLA with peritonitis if surgical intervention is too risky.