Vorinostat, temozolomide or bevacizumab with irradiation and maintenance BEV/TMZ in pediatric high-grade glioma: A Children's Oncology Group Study.

Background: Outcomes for children with high-grade gliomas (HGG) remain poor. This multicenter phase II trial evaluated whether concurrent use of vorinostat or bevacizumab with focal radiotherapy (RT) improved 1-year event-free survival (EFS) compared to temozolomide in children with newly diagnosed HGG who received maintenance temozolomide and bevacizumab. Methods: Patients ≥ 3 and < 22 years with localized, non-brainstem HGG were randomized to receive RT (dose 54-59.4Gy) with vorinostat, temozolomide, or bevacizumab followed by 12 cycles of bevacizumab and temozolomide maintenance therapy. Results: Among 90 patients randomized, the 1-year EFS for concurrent bevacizumab, vorinostat, or temozolomide with RT was 43.8% (±8.8%), 41.4% (±9.2%), and 59.3% (±9.5%), respectively, with no significant difference among treatment arms. Three- and five-year EFS for the entire cohort was 14.8% and 13.4%, respectively, with no significant EFS difference among the chemoradiotherapy arms. IDH mutations were associated with more favorable EFS (P = .03), whereas H3.3 K27M mutations (P = .0045) and alterations in PIK3CA or PTEN (P = .025) were associated with worse outcomes. Patients with telomerase- and alternative lengthening of telomeres (ALT)-negative tumors (n = 4) had an EFS of 100%, significantly greater than those with ALT or telomerase, or both (P = .002). While there was no difference in outcomes based on TERT expression, high TERC expression was associated with inferior survival independent of the telomere maintenance mechanism (P = .0012). Conclusions: Chemoradiotherapy with vorinostat or bevacizumab is not superior to temozolomide in children with newly diagnosed HGG. Patients with telomerase- and ALT-negative tumors had higher EFS suggesting that, if reproduced, mechanism of telomere maintenance should be considered in molecular-risk stratification in future studies.

Preclinical pediatric brain tumor models for immunotherapy: Hurdles and a way forward.

Brain tumors are the most common solid tumor in children and the leading cause of cancer-related deaths. Over the last few years, improvements have been made in the diagnosis and treatment of children with Central Nervous System tumors. Unfortunately, for many patients with high-grade tumors, the overall prognosis remains poor. Lower survival rates are partly attributed to the lack of efficacious therapies. The advent and success of immune checkpoint inhibitors (ICIs) in adults have sparked interest in investigating the utility of these therapies alone or in combination with other drug treatments in pediatric patients. However, to achieve improved clinical outcomes, the establishment and selection of relevant and robust preclinical pediatric high-grade brain tumor models is imperative. Here, we review the information that influenced our model selection as we embarked on an international collaborative study to test ICIs in combination with epigenetic modifying agents to enhance adaptive immunity to treat pediatric brain tumors. We also share challenges that we faced and potential solutions.

Enhanced Performance of Artificial-Neural-Network-Based Equalization for Short-Haul Fiber-Optic Communications.

This work proposes an efficient and easy-to-implement single-layer artificial neural network (ANN)-based equalizer with improved compensation performance. The proposed equalizer is used for effectively mitigating the distortions induced in the short-haul fiber-optic communication systems based on intensity modulation and direct detection (IMDD). The compensation performance of the ANN equalizer is significantly improved, exploiting an introduced advanced training scheme. The efficiency and robustness of the proposed ANN equalizer are illustrated through 10- and 28-Gbaud short-reach optical-fiber communication systems. Compared to the efficient but computationally expensive maximum likelihood sequence estimator (MLSE), the proposed ANN equalizer not only significantly reduces its computational equalization cost and storage memory requirements, but it also outperforms its bit error rate performance.

Hepatitis B virus infection in Saudi Arabia and the UAE: Public health challenges and their remedial measures.

BACKGROUND: Hepatitis B virus (HBV) infection is a major public health concern globally with higher prevalence in Middle Eastern countries. Both Saudi Arabia and the UAE face critical challenges in HBV treatment and management despite the implementation of a mass vaccination program. This review aimed to understand the gaps and unmet needs related to HBV infection, public health challenges associated with its diagnosis, and treatment barriers in Saudi Arabia and the UAE. Additionally, the review aimed to provide the best practices in the HBV care pathway for effective remedial measures and disease reduction. METHODS: The literature search was done from Pubmed. RESULTS: The lack of disease awareness and knowledge about disease transmission among patients and their family members and healthcare professionals, lack of proper screening, underdiagnosis, social stigma, lack of established referral system, and treatment cost are the primary barriers to HBV diagnosis and management. CONCLUSION: Appropriate healthcare initiatives should be undertaken to lower the disease burden in Saudi Arabia and the UAE.

Alternative Lengthening of Telomeres in Pediatric High-Grade Glioma and Therapeutic Implications.

Pediatric high-grade gliomas (pHGGs), including diffuse intrinsic pontine glioma (DIPG), are highly aggressive tumors with dismal prognoses despite multimodal therapy including surgery, radiation therapy, and chemotherapy. To achieve cellular immortality cancer cells must overcome replicative senescence and apoptosis by activating telomere maintenance mechanisms (TMMs) through the reactivation of telomerase activity or using alternative lengthening of telomere (ALT) pathways. Although the ALT phenotype is more prevalent in pHGGs compared to adult HGGs, the molecular pathway and the prognostic significance of ALT activation are not well understood in pHGGs. Here, we report the heterogeneity of TMM in pHGGs and their association with genetic alterations. Additionally, we show that sensitivity to the protein kinase ataxia telangiectasia- and RAD3-related protein (ATR) inhibitor and the ATR downstream target CHK1 is not specific to pHGG ALT-positive cells. Together, these findings underscore the need for novel therapeutic strategies to target ALT in pHGG tumors.

Impact of Donation After Circulatory Death Allografts on Outcomes Following Simultaneous Liver-Kidney Transplant: A Single-Center Experience and Review of the Literature.

OBJECTIVES: Limited data exist on outcomes after simultaneous liver-kidney transplants with extended criteria donor grafts. We compared outcomes in recipients of simultaneous liver-kidney transplants with donation after circulatory death versus donation after brain death grafts. MATERIALS AND METHODS: This retrospective analysis included all liver transplants performed over a 7-year period at a single center. We compared categorical variables using the chi-square test and continuous variables using the t test. We compared survival using the Kaplan-Meier method and performed a univariate analysis of predictors of outcomes using Cox regression method. RESULTS: Over the study period, 196 patients underwent liver transplant, with 33 (16.8%) undergoing simultaneous liver-kidney transplant. In this cohort, 23 and 10 patients, respectively, received grafts from donors after brain death versus circulatory death. Both groups were comparable with respect to age, sex, hepatitis C virus status, and presence of hepatocellular carcinoma. Median (range) Model for End-Stage Liver Disease score was higher in recipients of donation after brain death grafts (37 [26-40] vs 23 [21-24]; P < .01). Liver allograft survival was comparable in donation after brain death versus donation after circulatory death recipients (P = .82) at 1 year (64.0% vs 66.7%), 3 years (57.6% vs 55.6%), and 5 years (57.6% vs 55.6%). Patient survival was also comparable (P = .89) at 1 year (70.1% vs 77.8%), 3 years (63.1% vs 55.6%), and 5 years (63.1% vs 55.6%). Graft outcomes remained similar even after adjustment for Model for End-Stage Liver Disease score at transplant (hazard ratio 0.58; 95% CI, 0.14-2.44; P = .45). Univariate analysis of predictors of patient survival after simultaneous liver- kidney transplant showed a trend toward statistical significance with recipient age and donor male sex. CONCLUSIONS: Grafts from donors after circulatory death could help safely expand the donor pool in patients undergoing simultaneous liver-kidney transplant without compromising outcomes.

Validation of an LC-MS/MS method for quantitation of fostemsavir in plasma.

BACKGROUND: A novel, sensitive and specific LC-MS/MS technique was developed and validated for the quantification of fostemsavir in human plasma and its pharmacokinetic application in rabbits. METHODS: Chromatographic separation of the fostemsavir and fosamprenavir (internal standard) were achieved on Zorbax C18 (50 mm × 2 mm × 5 µm) column with 0.80 mL/min flow rate and coupled with API6000 triple quadrupole MS in multi reaction monitoring mode by applying mass transitions m/z 584.16/105.03 for fostemsavir and m/z 586.19/57.07 for the internal standard. RESULTS: The calibration curve exhibited linearity in concentration range of 58.5-2340.0 ng/mL for fostemsavir. The LLOQ was 58.5 ng/mL. The validated LC-MS/MS process was effectively applied for the analysis of plasma in healthy rabbits for determinations of Fostemsavir. From the pharmacokinetic data, the mean of Cmax and Tmax were 198.19 ± 5.85 ng/mL and 2.42 ± 0.13, respectively. Plasma concentration reduced with t1/2 of 7.02 ± 0.14. AUC0→Last value obtained was 2374.87 ± 29.75 ng. h/ml, respectively. CONCLUSION: In summary, the developed method has been successfully validated and pharmacokinetic parameters were demonstrated after oral administration of Fostemsavir to healthy rabbits.

Natural Intelligence as the Brain of Intelligent Systems.

This article discusses the concept and applications of cognitive dynamic systems (CDS), which are a type of intelligent system inspired by the brain. There are two branches of CDS, one for linear and Gaussian environments (LGEs), such as cognitive radio and cognitive radar, and another one for non-Gaussian and nonlinear environments (NGNLEs), such as cyber processing in smart systems. Both branches use the same principle, called the perception action cycle (PAC), to make decisions. The focus of this review is on the applications of CDS, including cognitive radios, cognitive radar, cognitive control, cyber security, self-driving cars, and smart grids for LGEs. For NGNLEs, the article reviews the use of CDS in smart e-healthcare applications and software-defined optical communication systems (SDOCS), such as smart fiber optic links. The results of implementing CDS in these systems are very promising, with improved accuracy, performance, and lower computational costs. For example, CDS implementation in cognitive radars achieved a range estimation error that is as good as 0.47 (m) and a velocity estimation error of 3.30 (m/s), outperforming traditional active radars. Similarly, CDS implementation in smart fiber optic links improved the quality factor by 7 dB and the maximum achievable data rate by 43% compared to those of other mitigation techniques.

Generation of High-Value Genomic Resource in Rice: A "Subgenomic Library" of Low-Light Tolerant Rice Cultivar Swarnaprabha.

Rice is the major staple food crop for more than 50% of the world's total population, and its production is of immense importance for global food security. As a photophilic plant, its yield is governed by the quality and duration of light. Like all photosynthesizing plants, rice perceives the changes in the intensity of environmental light using phytochromes as photoreceptors, and it initiates a morphological response that is termed as the shade-avoidance response (SAR). Phytochromes (PHYs) are the most important photoreceptor family, and they are primarily responsible for the absorption of the red (R) and far-red (FR) spectra of light. In our endeavor, we identified the morphological differences between two contrasting cultivars of rice: IR-64 (low-light susceptible) and Swarnaprabha (low-light tolerant), and we observed the phenological differences in their growth in response to the reduced light conditions. In order to create genomic resources for low-light tolerant rice, we constructed a subgenomic library of Swarnaprabha that expedited our efforts to isolate light-responsive photoreceptors. The titer of the library was found to be 3.22 × 105 cfu/mL, and the constructed library comprised clones of 4-9 kb in length. The library was found to be highly efficient as per the number of recombinant clones. The subgenomic library will serve as a genomic resource for the Gramineae community to isolate photoreceptors and other genes from rice.

Limitations of radiosensitization by direct telomerase inhibition to treat high-risk medulloblastoma.

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Previous studies have elucidated the genomic landscape of MB leading to the recognition of four core molecular subgroups (WNT, SHH, group 3 and group 4) with distinct clinical outcomes. Group 3 has the worst prognosis of all MB. Radiotherapy (RT) remains a major component in the treatment of poor prognosis MB but is rarely curative alone and is associated with acute and long-term toxicities. A hallmark of cancer cells is their unlimited proliferative potential which correlates closely with telomere length. The vast majority of malignant tumors activate telomerase to maintain telomere length, whereas this activity is barely detectable in most normal human somatic tissues, making telomerase inhibition a rational therapeutic target in the setting of cancer recurrence and therapy resistance. We and others have previously shown that short telomeres confer sensitivity to ionizing radiation (IR) suggesting that telomerase inhibition mediated telomere shortening will improve the efficacy of RT while minimizing its side effects. Here, we investigated the efficacy of the combination of IR with IMT, a potent telomerase inhibitor, in an in vivo model of group 3 MB. Our results indicate that although IMT inhibited MB telomerase activity resulting in telomere shortening and delayed tumor growth, the combination with IR did not prevent tumor recurrence and did not improve survival compared to the treatment with IR alone. Together, these findings suggest that the radiosensitization by direct telomerase inhibition is not an effective approach to treat high-risk pediatric brain tumors.

Whipple's Disease (WD) Without Arthropathy in an Immunocompromised Patient.

Whipple's disease (WD) is a rare disorder caused by the pathogen Tropheryma whipplei (T. whipplei). We report a unique presentation of WD in which the patient did not exhibit arthralgia which is characteristic of this disease. A 67-year-old man with a history of chronic hepatitis B infection and human immunodeficiency virus (HIV) infection presented with weight loss, nausea, vomiting, and myalgia. Endoscopy demonstrated erythema in the gastric body, lymphangiectasia of the duodenum, and increased granularity of the terminal ileum. Mucosal biopsies revealed macrophages in the lamina propria with focal histiocytic aggregates throughout the small bowel and cecum, consistent with WD. Confirmatory T. whipplei polymerase chain reaction(PCR) testing was positive. WD is a rare diagnosis that must be considered in the differential diagnoses of patients presenting with unexplained nausea, vomiting, diarrhea, and anemia. Furthermore, in patients with HIV, the possibilities would also include opportunistic gastrointestinal pathogens. Classic WD is characterized by diarrhea, weight loss, abdominal pain, and extra-intestinal involvement manifesting as joint pain. We describe a case of WD occurring in a patient with HIV, without the disease's characteristic joint involvement.

Impact of Donation After Circulatory Death Allografts on Outcomes After Liver Transplant for Hepatitis C: A Single-Center Experience and Review of the Literature.

OBJECTIVES: We investigated the impact of liver transplant from donors after circulatory death on incidence and severity of recurrent hepatitis C virus infection, graft and patient survival and aimed to identify predictors of outcomes. MATERIALS AND METHODS: We retrospectively reviewed all liver transplants performed at a single center (July 2007-February 2014). Patients with hepatitis C who underwent liver transplant from donors after circulatory death (group 1) were compared with hepatitis C patients who received grafts from donors after brain death (group 2) and patients without hepatitis C who received grafts from donors after circulatory death (group 3).We used the Kaplan-Meier method for survival analysis and performed a multivariable analysis for predictors of outcomes using Cox regression. Competing risk was used to analyze hepatitis C recurrence. RESULTS: Of 196 patients, 107 were included: 25 in group 1, 46 in group 2, and 36 in group 3. All 3 groups were comparable, except for longer cold ischemia time (P < .01) in group 1, lower Model for End-Stage Liver Disease score at transplant in groups 1 and 3 (P < .01), and greater proportion of recipients with hepatocellular carcinoma in groups 1 and 2 (P = .02). Hepatitis C recurrence and severe recurrence at 1 and 3 years were higher in group 1 (but not statistically significant). Severe recurrence was noted in 17% versus 8% at 1 year (P = .12) and 30% versus 14% at 3 years (P = .08). Graft and patient survival rates at 1, 3, and 5 years were comparable in all 3 study groups. CONCLUSIONS: Recurrent hepatitis C, including severe recurrence, was greater following donation after circulatory death compared with donation after brain death liver transplant. However, graft survival and patient survival were comparable, including in recipients of donation after circulatory death grafts without hepatitis C.

Adaptive digital back propagation exploiting adjoint-based optimization for fiber-optic communications.

This work proposes a novel and powerful adaptive digital back propagation (A-DBP) method with a fast adaption process. Given that the total transmission distance is known, the proposed A-DBP algorithm blindly compensates for the linear and nonlinear distortions of optical fiber transmission systems and networks, without knowing the launch power and channel parameters. An adjoint-based optimization (ABO) technique is proposed to significantly accelerate the parameters estimation of the A-DBP. The ABO algorithm utilizes a sequential quadratic programming (SQP) method coupled with an adjoint sensitivity analysis (ASA) approach to rapidly solve the A-DBP training problem. The design parameters are optimized using the minimum overhead of only one extra system simulation. Regardless of the number of A-DBP design parameters, the derivatives of the training objective function with respect to all parameters are estimated using only one extra adjoint system simulation per optimization iterate. This is contrasted with the traditional finite-difference (FD)-based optimization methods whose sensitivity analysis calculations cost per iterate scales linearly with the number of parameters. The robustness, performance, and efficiency of the proposed A-DBP algorithm are demonstrated through applying it to mitigate the distortions of 4-span and 20-span optical fiber communication systems. Coarse-mesh A-DBPs with less number of virtual spans are also used to significantly reduce the computational complexity of the equalizer, achieving compensation performance higher than that obtained using the coarse-mesh DBP with the exact channel parameters and full number of virtual spans.

Living Donor Liver Transplantation With Augmented Venous Outflow and Splenectomy: A Promised Land for Small Left Lobe Grafts.

OBJECTIVE: Living donor liver transplantation (LDLT) using small grafts, especially left lobe grafts (H1234-MHV) (LLG), continues to be a challenge due to small-for-size syndrome (SFSS). We herein demonstrate that with surgical modifications, outcomes with small grafts can be improved. METHODS: Between 2012 and 2020, we performed 130 adult LDLT using 61 (47%) LLG (H1234-MHV) in a single Enterprise. The median graft-to-recipient weight ratio was 0.84%, with graft-to-recipient weight ratio <0.7% accounting for 22%. Splenectomy was performed in 72 (56%) patients for inflow modulation before (n=50) or after (n=22) graft reperfusion. In LLG-LDLT, venous outflow was achieved using all three recipient hepatic veins. In right lobe graft (H5678) (RLG)-LDLT, the augmented graft right hepatic vein was anastomosed to the recipient's cava with a large cavotomy. Outcome measures include SFSS, early allograft dysfunction (EAD), and survival. RESULTS: Graft survival rates at 1, 3, and 5 years were 94%, 90%, and 83%, respectively, with no differences between LLG (H1234-MHV) and RLG (H5678). Splenectomy significantly reduced portal flow without increasing the complication rate. Despite the aggressive use of small grafts, SFSS and EAD developed in only 1 (0.8%) and 18 (13.8%) patients, respectively. Multivariable logistic regression revealed model for end-stage liver disease score and LLG (H1234-MHV) as independent risk factors for EAD and splenectomy as a protective factor (odds ratio: 0.09; P =0.03). For LLG (H1234-MHV)-LDLT, patients who underwent prereperfusion splenectomy tended to have better 1-year graft survival than those receiving postreperfusion splenectomy. CONCLUSIONS: LLG (H1234-MHV) are feasible in adult LDLT with excellent outcomes comparable to RLG (H5678). Venous outflow augmentation and splenectomy help lower the threshold of using small-for-size grafts without compromising graft survival.

Post-cholecystectomy Mirizzi Syndrome.

Post-cholecystectomy Mirizzi syndrome (PCMS) is characterized by symptoms of recurrent abdominal pain, jaundice, and fever in patients who underwent cholecystectomy. Imaging is crucial in the diagnosis of PCMS and Mirizzi syndrome. Imaging modalities have evolved over the years with abdominal ultrasonography, computed tomography of the abdomen, and magnetic resonance cholangiopancreatography being used in the diagnosis of PCMS and Mirizzi syndrome. The imaging findings show obstruction of the common hepatic duct due to impingement by a stone in the cystic duct or gallbladder infundibulum. PCMS management has evolved over the years with the current first-line management being endoscopic intervention. This case describes a 61-year-old male presenting with recurrent right upper quadrant pain two years after undergoing cholecystectomy due to cholelithiasis. The patient was later diagnosed with PCMS, and endoscopic management was performed with complete resolution of the symptoms.

Phase I study of ribociclib and everolimus in children with newly diagnosed DIPG and high-grade glioma: A CONNECT pediatric neuro-oncology consortium report.

Background: Genomic aberrations in the cell cycle and PI3K/Akt/mTOR pathways have been reported in diffuse intrinsic pontine glioma (DIPG) and high-grade glioma (HGG). Dual inhibition of CDK4/6 and mTOR has biologic rationale and minimal overlapping toxicities. This study determined the recommended phase 2 dose (RP2D) of ribociclib and everolimus following radiotherapy in children with DIPG and HGG. Methods: Patients were enrolled according to a Rolling-6 design and received ribociclib and everolimus once daily for 21 and 28 days, respectively. All patients with HGG and biopsied DIPG were screened for retinoblastoma protein presence by immunohistochemistry. Pharmacokinetics were analyzed. Results: Nineteen patients enrolled (median age: 8 years [range: 2-18]). Three patients enrolled at each dose level 1 and 2 without dose-limiting toxicities (DLT). Thirteen patients were enrolled at dose level 3, with one patient experiencing a DLT (grade 3 infection). One patient came off therapy before cycle 9 due to cardiac toxicity. The most common grade 3/4 toxicities were neutropenia (33%), leucopenia (17%), and lymphopenia (11%). Steady-state everolimus exposures in combination were 1.9 ± 0.9-fold higher than single-agent administration. Median overall survival for 15 patients with DIPG was 13.9 months; median event-free survival for four patients with HGG was 10.5 months. Two longer survivors had tumor molecular profiling identifying CDKN2A/B deletion and CDK4 overexpression. Conclusion: The combination of ribociclib and everolimus following radiotherapy in children with newly diagnosed DIPG and HGG was well tolerated, with a RP2D of ribociclib 170 mg/m2 and everolimus 1.5 mg/m2. Results will inform a molecularly guided phase II study underway to evaluate efficacy.

Free Space Ground to Satellite Optical Communications Using Kramers-Kronig Transceiver in the Presence of Atmospheric Turbulence.

Coherent detection provides the optimum performance for free space optical (FSO) communication systems. However, such detection systems are expensive and require digital phase noise compensation. In this paper, the transmission performance of long-haul FSO system for ground-to-satellite communication based on a Kramers-Kronig (KK) transceiver is evaluated. KK transceivers utilize inexpensive direct detection receivers and the signal phase is retrieved from the received current using the well-known KK relations. KK transceivers are not sensitive to the laser phase noise and, hence, inexpensive lasers with large linewidths can be used at the transmitter. The transmission performance of coherent and KK transceivers is compared in various scenarios such as satellite-to-ground, satellite-to-satellite, and ground-to-satellite for weak, moderate, and strong turbulence. The results show that the transmission performance of a system based on the KK transceiver is comparable to that based on a coherent transceiver, but at a significantly lower system cost and complexity. It is shown that in the absence of turbulence, the coherent receiver has a ~3 dB performance advantage over the KK receiver. However, in the presence of strong turbulence, this performance advantage becomes negligible.

Demographic Profile and Prescribing Patterns of Anti-epileptic Drugs in Indian Epilepsy Patients: Electronic Medical Record-Based Nation-Wide Retrospective Cohort Study.

The aim of this study was to provide real-world data on clinical characteristics, risk factors, and treatment patterns in Indian patients with epilepsy. Electronic medical record (EMR) data of patients diagnosed with epilepsy between January 2001 and December 2019, which included demographics, diagnosis, anti-epileptic drug usage, and underlying risk factors were evaluated. The majority of patients were between the age group of 18 and 55 years (n=3,186), with males accounting for 62% and the remaining 38% being females. Further, the most common comorbidity was hypertension (23.3%, n=1,470), followed by diabetes mellitus (10.8%, n=683) and depression (9.4%, n=597). The most prevalent form of epilepsy was focal epilepsy (n=5,141 81.4%), followed by generalized epilepsy (n=601). Focal epilepsy was most prevalent in males (62%, n=3,167) and most common in the age group of 18-55 years (50.3%, n=2588). Anti-epileptic drug (AED) usage data from 6,318 patients showed that the most commonly prescribed AED alone or in combination for both focal and generalized epilepsy was levetiracetam (41.8%, n= 2645). Data collected from this study are aligned but do not completely agree with the Guidelines for the Management of Epilepsy in India (GEMIND). This affirms treatment initiation with AED monotherapy; however, the treatment choices do not necessarily follow the recommended guidelines to select conventional AEDs, at low strengths, at initiation.

Impact of pediatric versus adult colonoscope on terminal ileum intubation: a retrospective study.

Background: Various possible predictors of successful terminal ileal intubation (TII) have been explored but the role of the type of colonoscope is unclear. Methods: We carried out a retrospective review of a prospectively collected database of all colonoscopies performed at a single endoscopy unit between May 2015 and July 2020. The primary outcome measure was successful TII in patients with specific indications for ileal examination. The primary predictor was the type of endoscope, pediatric or adult, used during the procedure. Univariate and multivariate analyses were performed. Results: In 5845 colonoscopies fulfilling the study criteria, the overall TII rate was 67.8%. In univariate analysis, the use of a pediatric colonoscope was associated with a higher TII rate (72.1% vs. 58.8%, P<0.001). Other variables associated with successful TII based on univariate analysis included the patient's age, male sex, body mass index, endoscopists' specialty, place of training, shorter colonoscope insertion time, shorter duration of the procedure, longer withdrawal time, procedures performed in the afternoon, type of sedation administered during colonoscopy, and cleanliness of the colon. Multivariate analysis yielded an adjusted odds ratio (OR) of 1.40 (95% confidence interval [CI] 1.21-1.62) for the use of a pediatric colonoscope. Propensity score-matching analysis also showed superiority of the pediatric colonoscope in achieving TII compared to an adult colonoscope, OR 1.35 (95%CI 1.17-1.57). Conclusions: Pediatric colonoscope increases the success of TII during colonoscopy. For endoscopists performing colonoscopy with intent to examine the terminal ileum, it is recommended to choose a pediatric colonoscope to maximize the success rate.