Evaluation of a pain management program for patients with median arcuate ligament syndrome.

Objectives: Median arcuate ligament syndrome is a complex disorder potentially caused by variation in the position of the median arcuate ligament. Symptomology involves chronic abdominal pain, nausea, and malnourishment. Pain management modalities and short-term outcomes for patients undergoing operative surgery for median arcuate ligament syndrome have yet to be fully evaluated. Our hospital implemented a pain management consultation program in 2017 focused on perioperative pain management. The objective of this study is to assess if the introduction of a pain management consultation program concurrent with median arcuate ligament syndrome surgery impacts patient outcomes and post-operative pain management strategies in these patients. Methods: De-identified data was collected retrospectively from our hospital's electronic medical records system, identifying median arcuate ligament syndrome patients and using International Classification of Diseases (ICD) and Current Procedural Terminology (CPT) codes from September 2017 to August 2021. Patients were grouped into the "consultation" cohort if they had scheduled and attended a pre-operative pain consultation. Pre-operative and discharge medications, pain scores, and demographics were collected to evaluate if the initiative impacted outcomes. Results: Median arcuate ligament syndrome patients who had a pre-operative pain management consultation had higher rates of pre-operative opioid (35.5%; p = 0.01) and non-opioid use (60.7%; p < 0.001). Patients without a pre-operative consultation that did not use opioids pre-operatively were more likely to be discharged on one or more opioids. Differences were also found for psychiatric medication at discharge (p < 0.001) with patients receiving pain consultation indicating higher percentages of use. Conclusion: Special consideration on prescribing pain medication should be part of discharge planning for median arcuate ligament syndrome patients. Addition of a pain management consultation can aid in these decisions.

Maternal circulating concentrations of soluble Fas and Elabela in early- and late-onset preeclampsia.

OBJECTIVE: The Fas/Fas ligand (FASL) system and Elabela-apelin receptor signaling pathways are implicated in the pathophysiology of preeclampsia. The aim of the current study was to investigate whether a model combining the measurement of sFas and Elabela in the maternal circulation may serve as a clinical biomarker for early- and/or late-onset preeclampsia more effectively than measures of each biomarker individually. METHODS: Blood samples were collected from 214 women in the following groups: (1) normal pregnancy sampled <34 weeks of gestation (n = 56); (2) patients who developed early-onset preeclampsia (n = 54); (3) normal pregnancy sampled ≥34 weeks of gestation (n = 52); (4) patients who developed late-onset preeclampsia (n = 52). Maternal circulating soluble Fas and Elabela concentrations were determined using sensitive and validated immunoassays. Two sample t-tests, multivariate logistic regression, and receiver operating characteristic curves were used for analyses. RESULTS: (1) Women with early-onset preeclampsia, and those with late-onset preeclampsia with placental lesions of maternal vascular malperfusion, had increased concentrations of sFas compared to their gestational age-matched normal controls; (2) women with late-onset preeclampsia, but not those with early-onset preeclampsia, had increased concentrations of Elabela compared to their gestational age-matched counterparts; and (3) an increase in both Elabela and sFas concentrations was more strongly associated with late-onset preeclampsia than early-onset preeclampsia relative to models including either of the markers alone. CONCLUSIONS: A combined model of maternal sFas and Elabela concentrations provides a stronger association with late-onset preeclampsia than either protein alone. This finding demonstrates the possibility to improve the classification of late-onset preeclampsia by combining the results of both molecular biomarkers.

Clinical Response to Celiac Plexus Block Confirms the Neurogenic Etiology of Median Arcuate Ligament Syndrome.

PURPOSE: To evaluate the response of median arcuate ligament syndrome (MALS) symptoms, including postprandial pain, nausea, and vomiting, to celiac plexus block (CPB) and correlate the response with arterial anatomy. MATERIALS AND METHODS: In a single-institution, retrospective cohort of clinically diagnosed MALS patients, 96 patients (female, 75; male, 21; mean age, 27 years) underwent 103 computed tomography‒guided percutaneous CPB procedures. Imaging, procedural, and clinical reports were reviewed. Primary outcomes evaluated were technical success, change in self-reported pain score, and change in nausea and vomiting. RESULTS: Computed tomography imaging before the procedure was available for 81 of 96 patients and demonstrated findings of celiac artery compression in 22 of 81 (27%) patients. Technical success was achieved in 102 of 103 cases. No major adverse events and 1 moderate adverse event were reported. The postprandial pain score decreased in 86 (84%) patients, and the mean score decreased from 6.3 to 0.9 points (P < .001). The prevalence of postprandial nausea decreased from 37.9% to 11.6% (P < .001) and that of vomiting decreased from 15.5% to 4.9% (P = .019). No differences were noted in pain relief after CPB between patients with and without celiac artery compression (P = .745). CONCLUSIONS: In patients with a clinical diagnosis of MALS, a large majority reported pain relief and decreased gastrointestinal symptoms after CPB. Pain relief did not correlate with the presence of celiac arterial abnormalities. This supports neuropathy as the primary etiology of MALS and suggests that the absence of celiac stenosis should not be used as an exclusion criterion.

Spectroscopic photoacoustic imaging of cervical tissue composition in excised human samples.

OBJECTIVE: Cervical remodeling is an important component in determining the pathway of parturition; therefore, assessing changes in cervical tissue composition may provide information about the cervix's status beyond the measurement of cervical length. Photoacoustic imaging is a non-invasive ultrasound-based technology that captures acoustic signals emitted by tissue components in response to laser pulses. This optical information allows for the determination of the collagen-to-water ratio (CWR). The purpose of this study was to compare the CWR evaluated by using spectroscopic photoacoustic (sPA) imaging in cervical samples obtained from pregnant and non-pregnant women. METHODS: This cross-sectional study comprised cervical biopsies obtained at the time of hysterectomy (n = 8) and at the scheduled cesarean delivery in pregnant women at term who were not in labor (n = 8). The cervical CWR was analyzed using a fiber-optic light-delivery system integrated to an ultrasound probe. The photoacoustic signals were acquired within the range of wavelengths that cover the peak absorption of collagen and water. Differences in the CWR between cervical samples from pregnant and non-pregnant women were analyzed. Hematoxylin and eosin and Sirius Red stains were used to compare the collagen content of cervical samples in these two groups. RESULTS: Eight cervix samples were obtained after hysterectomy, four from women ≤41 years of age and four from women ≥43 years of age; all cervical samples (n = 8) from pregnant women were obtained after 37 weeks of gestation at the time of cesarean section. The average CWR in cervical tissue samples from pregnant women was 18.7% (SD 7.5%), while in samples from non-pregnant women, it was 55.0% (SD 20.3%). There was a significantly higher CWR in the non-pregnant group compared to the pregnant group with a p-value <0.001. A subgroup analysis that compared the CWR in cervical samples from pregnant women and non-pregnant women ≤41 years of age (mean 46.3%, SD 23.1%) also showed a significantly higher CWR (p <0.01). Lower collagen content in the pregnancy group was confirmed by histological analysis, which revealed the loss of tissue composition, increased water content, and collagen degradation. CONCLUSION: The proposed bimodal ultrasound and sPA imaging system can provide information on the biochemical composition of cervical tissue in pregnant and non-pregnant women. Photoacoustic imaging showed a higher collagen content in cervical samples from non-pregnant women as compared to those from pregnant women, which matched with the histological analysis. This novel imaging method envisions a new potential for a sensitive diagnostic tool in the evaluation of cervical tissue composition.

Hypervolemic Hyponatremia as a Reversible Cause of Cardiopulmonary Arrest in a Postpartum Patient with Preeclampsia.

Although the incidence of preeclampsia complicated by hyponatremia is reportedly rare, the effects on the maternal outcome are severe and life-threatening. Here, we describe a case of a patient with preeclampsia who coded postpartum and was discovered to have hypervolemic hyponatremia and subsequently recovered after fluid diuresis and resolution of hyponatremia. While hyponatremia in preeclampsia is rare, it is even more unique for it to lead to cardiopulmonary arrest consequently. Therefore, sodium levels and fluid status should be monitored closely and promptly corrected without delay to prevent cardiopulmonary arrest in patients with preeclampsia.

Obesity and Pregnancy.

The worldwide rates of obesity have increased significantly in recent decades. In the United States, more than 50% of pregnant women are overweight or obese. Obese gravid women are more prone to adverse pregnancy outcomes, including gestational diabetes, hypertensive disorders, and cardiovascular diseases. The adverse outcomes extend beyond the pregnant obese woman; offspring of obese women are themselves at increased risk of prematurity, fetal death, injury during birth, and transient respiratory problems and metabolic effects (ie, neonatal hypoglycemia). Furthermore, maternal obesity can predispose their offspring to long-term health problems, potentially generating an intergenerational cycle of obesity and insulin resistance.

Fetal Heart Rate Tracing Category II: A Broad Category in Need of Stratification.

Fetal heart rate (FHR) tracings are classified into 3 categories per the National Institute of Child Health and Human Development guidelines. There exists broad consensus on the recognition and management of categories I and III. However, a category II FHR tracing is considered "indeterminate" and cannot be classified as either reassuring or non-reassuring. Absence of variability and high frequency and increased depth of decelerations are the key determining factors that make a category II tracing non-reassuring and are associated with fetal metabolic acidosis. Periodic category II tracing is present in the majority of normal laboring patients. In the setting of a category II tracing, an initial attempt should be made for in utero resuscitation of the fetus. If the tracing fails to improve over a period of 1 to 2 hours, or the fetal tracing gradually deteriorates, a decision should be made for operative vaginal or cesarean delivery. Category II tracing management algorithms can aid in decision-making in this uncertain clinical scenario. Team training and simulation may improve team performance and have a positive impact on neonatal outcomes.

Vaginal host immune-microbiome interactions in a cohort of primarily African-American women who ultimately underwent spontaneous preterm birth or delivered at term.

BACKGROUND: Recent studies suggest that alterations in the vaginal microbiome allow for the assessment of the risk for spontaneous preterm birth (PTB), the leading cause of neonatal morbidity and mortality worldwide. However, the associations between the local immune response and the vaginal microbiome are still poorly understood. Herein, we characterize the vaginal host immune-microbiome interactions in women who ultimately underwent PTB and in those who delivered at term. METHODS: Vaginal fluid samples from 52 pregnant women (of whom 18 underwent PTB and 34 delivered at term) were collected between 10 and 32 weeks of gestation in a case-control study. Concentrations of 33 immune mediators were determined using sensitive and specific immunoassays. The previously published 16S rRNA gene sequence and bacterial phylotype data of these subjects were utilized in this study. Linear mixed effects models were utilized to test associations between vaginal immune mediator concentrations and bacterial phylotype relative abundances. RESULTS: 1) In the overall study population, vaginal concentrations of CXCL10, CCL2, CCL3, SLP1 and VEGF negatively correlated with non-Lactobacillus, Community State Type IV (CST IV) members of the vaginal microbiome; 2) CXCL10, in particular, negatively correlated with 15 bacterial phylotypes, most of which are typical members of CST IV, such as Gardnerella vaginalis, Megasphaera spp., and Atopobium vaginae; 3) Gemella spp., also members of CST IV, negatively correlated with vaginal concentrations of VEGF, CCL2, CCL3, SLPI, and CXCL10; 4) when comparing PTB cases to term controls, five soluble immune mediators (CCL26, CCL22, CCL2, CXCL10, and IL-16), especially CCL26, were negatively correlated with five typical members of CST IV: Sneathia sanguinegens, Parvimonas micra, Veillonellaceae, BVAB2, and Gemella spp.; and 5) Sneathia sanguinegens had stronger negative associations with all five soluble immune mediators (CCL26, CCL22, CCL2, CXCL10, and IL-16) in PTB cases than in term controls. CONCLUSIONS: The assessment of vaginal host immune-microbiome interactions revealed that specific soluble immune mediators, mainly CXCL10, negatively correlated with typical members of CST IV of the vaginal microbiome. Sneathia sanguinegens, in particular, had stronger negative associations with different immune mediators, including CXCL10 and CCL26, in women who ultimately underwent PTB compared to those who delivered at term. These findings provide insight into the vaginal host immune-microbiome interactions in normal and complicated pregnancies.

Cellular immune responses in amniotic fluid of women with a sonographic short cervix.

Objectives A sonographic short cervix is one of the strongest predictors of preterm delivery. However, the cellular immune composition of amniotic fluid in women with a short cervix has not yet been described. Herein, we determined cellular and soluble immune responses in amniotic fluid from pregnant women with a mid-trimester asymptomatic short cervix. Methods Amniotic fluid samples (n=77) were collected from asymptomatic women with a cervical length between 15 and 25 mm (n=36, short cervix) or ≤15 mm (n=41, severely short cervix) diagnosed by ultrasound. Flow cytometry and multiplex measurement of cytokines/chemokines were performed. Results (1) The cellular immune composition of amniotic fluid did not differ between women with a severely short cervix (≤15 mm) and those with a short cervix 15-25 mm; (2) amniotic fluid concentrations of multiple cytokines/chemokines were higher in women with a severely short cervix (≤15 mm) than in those with a short cervix 15-25 mm; (3) the cellular immune composition of amniotic fluid did not differ between women with a severely short cervix (≤15 mm) who ultimately underwent preterm delivery and those who delivered at term; and (4) amniotic fluid concentrations of IL-2, but not other immune mediators, were increased in women with a severely short cervix (≤15 mm) who ultimately delivered preterm compared to those who delivered at term. Conclusions Women with a severely short cervix (≤15 mm) have increased concentrations of pro-inflammatory mediators in the amniotic cavity; yet, these do not translate to changes in the cellular immune response.

Nursing Students' Attitudes Toward Lesbian, Gay, Bisexual, and Transgender Persons: An Integrative Review.

AIM: The aim of this study was to critically appraise and synthesize findings from studies on the attitudes of nursing students toward lesbian, gay, bisexual, and transgender (LGBT) persons. BACKGROUND: There is paucity of research to assess the attitudes of nursing students toward LGBT persons. METHOD: An electronic search was conducted using PubMed, Medline, Web of Science, EbscoHost, PsycInfo, and the Cumulative Index to Nursing and Allied Health Literature using medical subject headings terminologies. Search terms used included gay, lesbian, transgender, bisexual, LGBT, nursing students, baccalaureate nursing, undergraduate nursing, homophobia, homosexuality, sexual minority, attitudes, discrimination, and prejudice. RESULTS: Less than 50 percent of the studies (5 out of 12) suggested positively leaning attitudes of nursing students toward LGBT persons; six studies reported negative attitudes, and one study reported neutral attitudes. CONCLUSION: There are some indications that student attitudes may be moving toward positively leaning. Studies published before 2000 reported a preponderance of negative attitudes.

Publishing Trends in Two American Journals in Anesthesiology-Results of an 80-Year Geographical Survey.

BACKGROUND: We examined publication trends in two major American journals devoted to anesthesia to understand the geographical distribution of authorship and attempt to decipher the factors that influence this distribution. METHODS: In addition to bibliometric information for all articles published in Anesthesiology between 1941 and 2010 and Anesthesia & Analgesia between 1931 and 2010, we also collected information about the country, continent, and medical school or institution from which the articles were submitted. RESULTS: The top five countries that published research in these journals were the United States, Japan, Germany, Canada, and France. More than 50% of the published articles were submitted from the United States. However, US publications have steadily and significantly declined over the decades. Contributions from Europe and Asia (especially China) have shown marked increases. US spending on research, especially biomedical research, has remained essentially unchanged and declined in some areas, whereas it has increased steadily in some of the other countries we discuss. CONCLUSIONS: There is a significantly increased prominence in publishing from countries other than the United States. The reasons for this include the convenience of Web-based submission, an increased desire by researchers from around the world to publish in journals considered prestigious, English becoming the preferred language of communication amongst academicians in science, the advent of globalization, and a decrease in public research funding in the United States relative to other countries.

Angiojet thrombolysis and vena cava filter insertion in a case of a duplicated inferior vena cava.

OBJECTIVES: Duplication of the inferior vena cava (IVC) complicates interventional procedures. This case report aims to shed light on this unusual anomaly and the preoperative considerations necessary when treatment of venous thromboembolism is undertaken. METHODS: An IRB approved case report of a 58 year old woman presented emergently with right lower extremity phlegmasia due to extensive thrombosis of her right iliofemoral and infrarenal portion of her duplicated IVC. RESULTS: The patient underwent IVC filter placement and rheolytic thrombectomy with thrombolysis using the Angiojet device followed by venoplasty and stenting of the iliofemoral system and right IVC. Complete symptomatic and radiographic resolution on duplex imaging was achieved at 1 year follow up. CONCLUSIONS: With adequate preoperative awareness of IVC anomalies and treatment options available satisfactory results can be achieved and complications minimized for this unique patient population.

Angiogenesis: an adaptive dynamic biological patterning problem.

Formation of functionally adequate vascular networks by angiogenesis presents a problem in biological patterning. Generated without predetermined spatial patterns, networks must develop hierarchical tree-like structures for efficient convective transport over large distances, combined with dense space-filling meshes for short diffusion distances to every point in the tissue. Moreover, networks must be capable of restructuring in response to changing functional demands without interruption of blood flow. Here, theoretical simulations based on experimental data are used to demonstrate that this patterning problem can be solved through over-abundant stochastic generation of vessels in response to a growth factor generated in hypoxic tissue regions, in parallel with refinement by structural adaptation and pruning. Essential biological mechanisms for generation of adequate and efficient vascular patterns are identified and impairments in vascular properties resulting from defects in these mechanisms are predicted. The results provide a framework for understanding vascular network formation in normal or pathological conditions and for predicting effects of therapies targeting angiogenesis.

Clinical and anatomic outcomes of endovenous radiofrequency ablation performed on symptomatic small-diameter great saphenous veins.

OBJECTIVE: The efficacy of radiofrequency ablation (RFA) for symptomatic varicose veins is well established. Alternatively, there is less consensus and little data on outcomes when treating great saphenous veins (GSV) of small diameter (≤5 mm). The purpose of this study is to assess clinical and anatomical outcomes of RFA on symptomatic patients with small GSV. METHODS: A retrospective analysis was performed on our symptomatic patients who received RFA of incompetent GSV without any concomitant adjunctive procedures between January 2008 and December 2011. Limbs with GSV thigh diameter ≤5 mm and >5 mm on duplex while standing were subject to review. Clinical success was defined as an improvement in Venous Clinical Severity Score (VCSS) at 3 months. Anatomic success was defined as absence of venous flow ≤3 cm distal to the saphenofemoral junction on duplex ultrasound examination. Changes in CEAP class were noted. RESULTS: In 307 patients, 55 limbs in 44 patients met inclusion criteria. Baseline median VCSS was 4 (interquartile range [IQR], 4, 5) for those patients with diameter ≤5 mm. Clinical success was seen in 83% of limbs at 3 months with a median VCSS change of -2 (IQR, -3, -1). None of the treated limbs had phlebectomy for symptomatic refluxing GSV varicosities prior to 3-month follow up. One phlebectomy was performed for cosmesis at 78 days postprocedure. Anatomic success was achieved in 96% of limbs at 3 months. Baseline median CEAP was 2 (IQR, 2, 2). The median CEAP change at 3 months was 0 (IQR, -1, 0). One patient experienced thrombus extension into the saphenofemoral junction at 4 days. CONCLUSIONS: In our experience, RFA of symptomatic small-diameter GSV provides comparable clinical and anatomic outcomes to that of current published data. Our findings suggest that these patients benefit clinically from RFA.

Anesthetic Challenges in Robotic-assisted Urologic Surgery.

Robotic-assisted surgery has evolved over the past two decades with constantly improving technology, assisting surgeons in multiple subspecialty disciplines. The surgical requirements of lithotomy and steep Trendelenburg positions, along with the creation of a pneumoperitoneum and limited access to the patient, all present anesthetic management challenges in urologic surgery. Patient positioning requirements can cause significant physiologic effects and may result in many complications. Good communication among team members and knowledge of the nuances of robotic surgery have the potential to improve patient outcomes, increase efficiency, and reduce surgical and anesthetic complications.

Endovascular vs open repair for ruptured abdominal aortic aneurysm.

OBJECTIVE: Endovascular repair (EVAR) of ruptured abdominal aortic aneurysm (rAAA) has become first-line therapy at our institution and is performed under a standardized protocol. We compare perioperative mortality, midterm survival, and morbidity after EVAR and open surgical repair (OSR). METHODS: Records were retrospectively reviewed from May 2000 to September 2010 for repair of infrarenal rAAAs. Primary end points included perioperative mortality and midterm survival. Secondary end points included acute limb ischemia, length of stay, ventilator-dependent respiratory failure, myocardial infarction, renal failure, abdominal compartment syndrome, and secondary intervention. Statistical analysis was performed using the t-test, χ(2) test, the Fisher exact test, and logistic regression calculations. Midterm survival was assessed with Kaplan-Meier analysis and Cox proportional hazard models. RESULTS: Seventy-four infrarenal rAAAs were repaired, 19 by EVAR and 55 by OSR. Despite increased age and comorbidity in the EVAR patients, perioperative mortality was 15.7% for EVAR, which was significantly lower than the 49% for OSR (odds ratio, 0.19; 95% CI, 0.05-0.74; P = .008). Midterm survival also favored EVAR (hazard ratio, 0.40; 95% CI, 0.21-0.77; P = .028, adjusted for age and sex). Mean follow-up was 20 months, and 1-year survival was 60% for EVAR vs 45% for OSR. Mean length of stay for patients surviving >1 day was 10 days for EVAR and 21 days for OSR (P = .004). Ventilator-dependent respiratory failure was 5% in the EVAR group vs 42% for OSR (odds ratio, 0.08; 95% CI, 0.01-0.62; P = .001). CONCLUSIONS: EVAR of rAAA has a superior perioperative survival advantage and decreased morbidity vs OSR. Although not statistically significant, overall survival favors EVAR. We recommend that EVAR be considered as the first-line treatment of rAAAs and practiced as the standard of care.

Seizure sensitivity is ameliorated by targeted expression of K+-Cl- cotransporter function in the mushroom body of the Drosophila brain.

The kcc(DHS1) allele of kazachoc (kcc) was identified as a seizure-enhancer mutation exacerbating the bang-sensitive (BS) paralytic behavioral phenotypes of several seizure-sensitive Drosophila mutants. On their own, young kcc(DHS1) flies also display seizure-like behavior and demonstrate a reduced threshold for seizures induced by electroconvulsive shock. The product of kcc shows substantial homology to KCC2, the mammalian neuronal K(+)-Cl(-) cotransporter. The kcc(DHS1) allele is a hypomorph, and its seizure-like phenotype reflects reduced expression of the kcc gene. We report here that kcc functions as a K(+)-Cl(-) cotransporter when expressed heterologously in Xenopus laevis oocytes: under hypotonic conditions that induce oocyte swelling, oocytes that express Drosophila kcc display robust ion transport activity observed as a Cl(-)-dependent uptake of the K(+) congener (86)Rb(+). Ectopic, spatially restricted expression of a UAS-kcc(+) transgene was used to determine where cotransporter function is required in order to rescue the kcc(DHS1) BS paralytic phenotype. Interestingly, phenotypic rescue is largely accounted for by targeted, circumscribed expression in the mushroom bodies (MBs) and the ellipsoid body (EB) of the central complex. Intriguingly, we observed that MB induction of kcc(+) functioned as a general seizure suppressor in Drosophila. Drosophila MBs have generated considerable interest especially for their role as the neural substrate for olfactory learning and memory; they have not been previously implicated in seizure susceptibility. We show that kcc(DHS1) seizure sensitivity in MB neurons acts via a weakening of chemical synaptic inhibition by GABAergic transmission and suggest that this is due to disruption of intracellular Cl(-) gradients in MB neurons.

CT colonography versus colonoscopy for the detection of advanced neoplasia.

BACKGROUND: Advanced neoplasia represents the primary target for colorectal-cancer screening and prevention. We compared the diagnostic yield from parallel computed tomographic colonography (CTC) and optical colonoscopy (OC) screening programs. METHODS: We compared primary CTC screening in 3120 consecutive adults (mean [+/-SD] age, 57.0+/-7.2 years) with primary OC screening in 3163 consecutive adults (mean age, 58.1+/-7.8 years). The main outcome measures included the detection of advanced neoplasia (advanced adenomas and carcinomas) and the total number of harvested polyps. Referral for polypectomy during OC was offered for all CTC-detected polyps of at least 6 mm in size. Patients with one or two small polyps (6 to 9 mm) also were offered the option of CTC surveillance. During primary OC, nearly all detected polyps were removed, regardless of size, according to established practice guidelines. RESULTS: During CTC and OC screening, 123 and 121 advanced neoplasms were found, including 14 and 4 invasive cancers, respectively. The referral rate for OC in the primary CTC screening group was 7.9% (246 of 3120 patients). Advanced neoplasia was confirmed in 100 of the 3120 patients in the CTC group (3.2%) and in 107 of the 3163 patients in the OC group (3.4%), not including 158 patients with 193 unresected CTC-detected polyps of 6 to 9 mm who were undergoing surveillance. The total numbers of polyps removed in the CTC and OC groups were 561 and 2434, respectively. There were seven colonic perforations in the OC group and none in the CTC group. CONCLUSIONS: Primary CTC and OC screening strategies resulted in similar detection rates for advanced neoplasia, although the numbers of polypectomies and complications were considerably smaller in the CTC group. These findings support the use of CTC as a primary screening test before therapeutic OC.