Evaluating the antibody response elicited by diverse HIV envelope immunogens in the African green monkey (Vervet) model.

African Green (Vervet) monkeys have been extensively studied to understand the pathogenesis of infectious diseases. Using vervet monkeys as pre-clinical models may be an attractive option for low-resourced areas as they are found abundantly and their maintenance is more cost-effective than bigger primates such as rhesus macaques. We assessed the feasibility of using vervet monkeys as animal models to examine the immunogenicity of HIV envelope trimer immunogens in pre-clinical testing. Three groups of vervet monkeys were subcutaneously immunized with either the BG505 SOSIP.664 trimer, a novel subtype C SOSIP.664 trimer, CAP255, or a combination of BG505, CAP255 and CAP256.SU SOSIP.664 trimers. All groups of vervet monkeys developed robust binding antibodies by the second immunization with the peak antibody response occurring after the third immunization. Similar to binding, antibody dependent cellular phagocytosis was also observed in all the monkeys. While all animals developed potent, heterologous Tier 1 neutralizing antibody responses, autologous neutralization was limited with only half of the animals in each group developing responses to their vaccine-matched pseudovirus. These data suggest that the vervet monkey model may yield distinct antibody responses compared to other models. Further study is required to further determine the utility of this model in HIV immunization studies.

A novel velocity band energy workflow for fiber-optic DAS interpretation and multiphase flow characterization.

Distributed fiber-optic sensing continues to gain widespread adoption in the energy industry because of the numerous benefits it offers for real-time surface and subsurface monitoring of pipelines, wellbores, reservoirs, and storage infrastructure. In this study, we introduce a novel workflow to analyze optical fiber-based distributed acoustic sensor (DAS) data, which takes into account the speed of sound for a certain phase to filter the acoustic energy or signal contributed by that phase. This information is then utilized for the characterization of multiphase flow. The application of the proposed velocity band energy (VBE) workflow is demonstrated using a dataset acquired in a 5163-ft-deep wellbore, for estimating gas void fraction and real-time gas-liquid interface tracking across the length of the well. The workflow utilizes a series of signal processing and conditioning steps that aim to reduce noise and enhance the signals of interest. The insights from the new methodology will further assist in validating DAS-based flow monitoring algorithms, leak detection and quantification, and reservoir characterization.

Clinical Outcomes of Upper Extremity Nerve Transfers in Neuralgic Amyotrophy.

SUMMARY: Neuralgic amyotrophy (NA) is a disease affecting peripheral nerves. Treatment has historically been conservative, as the natural course of the disease was thought to be self-limiting. Recent work has demonstrated that as many as two-thirds of people with NA have persistent pain, fatigue, or weakness. At the authors' center, supercharged end-to-side (SETS) nerve transfers are commonly performed in patients with NA to optimize motor recovery while allowing for native axonal regrowth. The authors describe the technique and clinical outcomes of patients with NA affecting the anterior interosseous nerve (AIN) who were treated with SETS nerve transfer from extensor carpi radialis brevis to AIN. Ten patients (90% male; mean age, 51.3 ± 9.7 years) underwent extensor carpi radialis brevis-to-AIN transfer at a mean period of 6.4 ± 1.4 months after onset of symptoms. Mean postoperative follow-up duration was 14.8 ± 3.2 months. Before surgery, all patients demonstrated clinically significant weakness in the flexor pollicis longus (FPL), flexor digitorum profundus muscle to the index finger (FDP2), or both. FPL strength improved from a median Medical Research Council (MRC) grade of 1.5 to 4 ( P = 0.011) and FDP2 strength improved from a median MRC grade of 1 to 5 ( P = 0.016). A postoperative MRC grade of 4 or greater was achieved in nine of 10 (90%) FPL and 10 of 10 (100%) FDP muscles. This is the first report of SETS nerve transfer for the treatment of NA. The outcomes of this work suggest that SETS nerve transfers may be an option to optimize motor outcomes in patients with NA. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Swarm Intelligence Internet of Vehicles Approaches for Opportunistic Data Collection and Traffic Engineering in Smart City Waste Management.

Recent studies have shown the efficacy of mobile elements in optimizing the energy consumption of sensor nodes. Current data collection approaches for waste management applications focus on exploiting IoT-enabled technologies. However, these techniques are no longer sustainable in the context of smart city (SC) waste management applications due to the emergence of large-scale wireless sensor networks (LS-WSNs) in smart cities with sensor-based big data architectures. This paper proposes an energy-efficient swarm intelligence (SI) Internet of Vehicles (IoV)-based technique for opportunistic data collection and traffic engineering for SC waste management strategies. This is a novel IoV-based architecture exploiting the potential of vehicular networks for SC waste management strategies. The proposed technique involves deploying multiple data collector vehicles (DCVs) traversing the entire network for data gathering via a single-hop transmission. However, employing multiple DCVs comes with additional challenges including costs and network complexity. Thus, this paper proposes analytical-based methods to investigate critical tradeoffs in optimizing energy consumption for big data collection and transmission in an LS-WSN such as (1) finding the optimal number of data collector vehicles (DCVs) required in the network and (2) determining the optimal number of data collection points (DCPs) for the DCVs. These critical issues affect efficient SC waste management and have been overlooked by previous studies exploring waste management strategies. Simulation-based experiments using SI-based routing protocols validate the efficacy of the proposed method in terms of the evaluation metrics.

The Road to Elimination: Current State of Schistosomiasis Research and Progress Towards the End Game.

The new WHO Roadmap for Neglected Tropical Diseases targets the global elimination of schistosomiasis as a public health problem. To date, control strategies have focused on effective diagnostics, mass drug administration, complementary and integrative public health interventions. Non-mammalian intermediate hosts and other vertebrates promote transmission of schistosomiasis and have been utilized as experimental model systems. Experimental animal models that recapitulate schistosomiasis immunology, disease progression, and pathology observed in humans are important in testing and validation of control interventions. We discuss the pivotal value of these models in contributing to elimination of schistosomiasis. Treatment of schistosomiasis relies heavily on mass drug administration of praziquantel whose efficacy is comprised due to re-infections and experimental systems have revealed the inability to kill juvenile schistosomes. In terms of diagnosis, nonhuman primate models have demonstrated the low sensitivity of the gold standard Kato Katz smear technique. Antibody assays are valuable tools for evaluating efficacy of candidate vaccines, and sera from graded infection experiments are useful for evaluating diagnostic sensitivity of different targets. Lastly, the presence of Schistosomes can compromise the efficacy of vaccines to other infectious diseases and its elimination will benefit control programs of the other diseases. As the focus moves towards schistosomiasis elimination, it will be critical to integrate treatment, diagnostics, novel research tools such as sequencing, improved understanding of disease pathogenesis and utilization of experimental models to assist with evaluating performance of new approaches.

Relative Importance of Stochastic Assembly Process of Membrane Biofilm Increased as Biofilm Aged.

The relative importance of different ecological processes controlling biofilm community assembly over time on membranes with different surface characteristics has never been investigated in membrane bioreactors (MBRs). In this study, five ultrafiltration hollow-fiber membranes - having identical nominal pore size (0.1µm) but different hydrophobic or hydrophilic surface characteristics - were operated simultaneously in the same MBR tank with a constant flux of 10 liters per square meter per hour (LMH). In parallel, membrane modules operated without permeate flux (0 LMH) were submerged in the same MBR tank, to investigate the passive microbial adsorption onto different hydrophobic or hydrophilic membranes. Samples from the membrane biofilm were collected after 1, 10, 20, and 30days of continuous filtration. The membrane biofilm microbiome were investigated using 16S rRNA gene amplicon sequencing from DNA and cDNA samples. Similar beta diversity trends were observed for both DNA- and cDNA-based analyses. Beta diversity analyses revealed that the nature of the membrane surface (i.e., hydrophobic vs. hydrophilic) did not seem to have an effect in shaping the bacterial community, and a similar biofilm microbiome evolved for all types of membranes. Similarly, membrane modules operated with and without permeate flux did not significantly influence alpha and beta diversity of the membrane biofilm. Nevertheless, different-aged membrane biofilm samples exhibited significant differences. Proteobacteria was the most dominant phylum in early-stage membrane biofilm after 1 and 10days of filtration. Subsequently, the relative reads abundance of the phyla Bacteroidetes and Firmicutes increased within the membrane biofilm communities after 20 and 30days of filtration, possibly due to successional steps that lead to the formation of a relatively aged biofilm. Our findings indicate distinct membrane biofilm assembly patterns with different-aged biofilm. Ecological null model analyses revealed that the assembly of early-stage biofilm community developed after 1 and 10days of filtration was mainly governed by homogenous selection. As the biofilm aged (days 20 and 30), stochastic processes (e.g., ecological drift) started to become important in shaping the assembly of biofilm community.

Well-scale demonstration of distributed pressure sensing using fiber-optic DAS and DTS.

In this study, we used data from optical fiber-based Distributed Acoustic Sensor (DAS) and Distributed Temperature Sensor (DTS) to estimate pressure along the fiber. A machine learning workflow was developed and demonstrated using experimental datasets from gas-water flow tests conducted in a 5163-ft deep well instrumented with DAS, DTS, and four downhole pressure gauges. The workflow is successfully demonstrated on two experimental datasets, corresponding to different gas injection volumes, backpressure, injection methods, and water circulation rates. The workflow utilizes the random forest algorithm and involves a two-step process for distributed pressure prediction. In the first step, single-depth predictive modeling is performed to explore the underlying relationship between the DAS (in seven different frequency bands), DTS, and the gauge pressures at the four downhole locations. The single-depth analysis showed that the low-frequency components (< 2 Hz) of the DAS data, when combined with DTS, consistently demonstrate a superior capability in predicting pressure as compared to the higher frequency bands for both the datasets achieving an average coefficient of determination (or R2) of 0.96. This can be explained by the unique characteristic of low-frequency DAS which is sensitive to both the strain and temperature perturbations. In the second step, the DTS and the low-frequency DAS data from two gauge locations were used to predict pressures at different depths. The distributed pressure modeling achieved an average R2 of 0.95 and an average root mean squared error (RMSE) of 24 psi for the two datasets across the depths analyzed, demonstrating the distributed pressure measurement capability using the proposed workflow. A majority of the current DAS applications rely on the higher frequency components. This study presents a novel application of the low-frequency DAS combined with DTS for distributed pressure measurement.

Remind Me Again: Physician Response to Web Surveys: The Effect of Email Reminders Across 11 Opinion Survey Efforts at the American Board of Internal Medicine from 2017 to 2019.

For survey researchers, physicians in the United States are a difficult-to-reach subgroup. The purpose of this study is to quantify the effect of email reminders on web-based survey response rates targeting physicians. We conducted a retrospective analysis of 11 American Board of Internal Medicine surveys from 2017 to 2019. We compute aggregate response rates for the periods between weekly email contacts across the 11 surveys, while controlling for survey time to complete, physician age, gender, region, board certification status, and initial exam performance. The overall predicted response rate after six weekly email contacts was 23.7%, 95% CI: (17.1%, 33.0%). Across the 11 surveys, we found response rate for the first period to be 8.9%, 95% CI: (6.5%, 12.2%). We observed a 50% decrease in response from the first to the second period, which had a 4.4%, 95% CI: (3.2%, 6.2%), response rate. The third and fourth response periods yielded similar response rates of 3.0%, 95% CI: (2.3%, 3.9%) and 3.3%, 95%CI: (2.4%, 4.6%), respectively. The fifth and sixth response periods yielded similar response rates of 2.2%, 95%CI: (1.5%, 3.3%) and 1.9%, 95% CI: (1.3%, 2.7%), respectively. The results were further stratified into different levels of participant survey interest, and are helpful for cost and sample size considerations when designing a physician survey.

Infection of Chinese Rhesus Monkeys with a Subtype C SHIV Resulted in Attenuated In Vivo Viral Replication Despite Successful Animal-to-Animal Serial Passages.

Rhesus macaques can be readily infected with chimeric simian-human immunodeficiency viruses (SHIV) as a suitable virus challenge system for testing the efficacy of HIV vaccines. Three Chinese-origin rhesus macaques (ChRM) were inoculated intravenously (IV) with SHIVC109P4 in a rapid serial in vivo passage. SHIV recovered from the peripheral blood of the final ChRM was used to generate a ChRM-adapted virus challenge stock. This stock was titrated for the intrarectal route (IR) in 8 ChRMs using undiluted, 1:10 or 1:100 dilutions, to determine a suitable dose for use in future vaccine efficacy testing via repeated low-dose IR challenges. All 11 ChRMs were successfully infected, reaching similar median peak viraemias at 1-2 weeks post inoculation but undetectable levels by 8 weeks post inoculation. T-cell responses were detected in all animals and Tier 1 neutralizing antibodies (Nab) developed in 10 of 11 infected ChRMs. All ChRMs remained healthy and maintained normal CD4+ T cell counts. Sequence analyses showed >98% amino acid identity between the original inoculum and virus recovered at peak viraemia indicating only minimal changes in the env gene. Thus, while replication is limited over time, our adapted SHIV can be used to test for protection of virus acquisition in ChRMs.

The Perfect Storm: Exam of a Medical Error and Factors Contributing to Its Possible Escalation.

OBJECTIVE: After an initial medical misadventure, failure of recognition and continuing factors that could perpetuate the error are examined. METHODS: A critical evaluation of the continuum of care after the initial error was conducted through chart review and comparison to published standards. RESULTS: Analysis of the continuum of care after the original error demonstrated numerous system failures that should have alerted the providers to the initial error. DISCUSSION: Technology, electronic medical records, lack of critical communications, and short cuts have the potential to not recognize patient care safety issues and potential harm. CONCLUSIONS: Medical errors are multifactorial. Blame casting and accusations are not productive. Critical analysis of systems/processes, current technology, eliminating shortcuts, and critical communications may increase patient safety.

Noise induced quiescence of epileptic spike generation in patients with epilepsy.

Clinical scalp electroencephalographic recordings from patients with epilepsy are distinguished by the presence of epileptic discharges i.e. spikes or sharp waves. These often occur randomly on a background of fluctuating potentials. The spike rate varies between different brain states (sleep and awake) and patients. Epileptogenic tissue and regions near these often show increased spike rates in comparison to other cortical regions. Several studies have shown a relation between spike rate and background activity although the underlying reason for this is still poorly understood. Both these processes, spike occurrence and background activity show evidence of being at least partly stochastic processes. In this study we show that epileptic discharges seen on scalp electroencephalographic recordings and background activity are driven at least partly by a common biological noise. Furthermore, our results indicate noise induced quiescence of spike generation which, in analogy with computational models of spiking, indicate spikes to be generated by transitions between semi-stable states of the brain, similar to the generation of epileptic seizure activity. The deepened physiological understanding of spike generation in epilepsy that this study provides could be useful in the electrophysiological assessment of different therapies for epilepsy including the effect of different drugs or electrical stimulation.

A Specific Capsular Repair Technique Lowered Early Dislocations in Primary Total Hip Arthroplasty Through a Posterior Approach.

BACKGROUND: Dislocation is a challenging problem after total hip arthroplasty (THA). We sought to evaluate the incidence of early dislocation with 2 different posterior repair techniques after THA using a posterior approach. METHODS: From September of 2008 to August of 2019, we evaluated 841 THAs performed by a single surgeon using a posterior approach. Before November of 2015, the capsule was repaired to the greater trochanter (group 1, 605 patients). Starting November 2015, the posterior capsule was repaired in a side-to-side fashion (direct soft-tissue repair) (group 2, 236 patients). There was a mean follow-up of 31.1 months (range, 2.5-122.5 months). A multivariable logistic regression model was constructed to assess the impact of baseline patient and operative factors on the dislocation rate. RESULTS: There were 22 dislocations, all of which occurred in group 1. There were no dislocations in group 2. After adjusting for patient and operative factors, the direct soft-tissue repair had a large impact on the overall multivariable model as indicated by its effect likelihood ratio of 10.33 (P = .001); however, the odds ratio was not calculable for this factor, given that there were no dislocations in hips with direct soft-tissue repair. Increasing age was associated with an increased odds of dislocation (odds ratio, 1.04, P = .017), with an effect likelihood ratio of 6.25 (P = .012). CONCLUSIONS: Switching from a capsular repair to the greater trochanter to a side-to-side capsular repair was associated with a decreased rate of dislocation in primary THA through a posterior approach.

When worlds collide: Challenges to implementing communication research in community oncology practices.

OBJECTIVE: During a recent trial assessing the effectiveness of an online communication training for community practice oncologists, we encountered multiple barriers. METHODS: We asked oncologists to participate through the American Board of Internal Medicine (ABIM) Maintenance of Certification program. Oncologists collected 25 Clinician and Group Consumer Assessment of Healthcare Providers (CAHPS) surveys from patients and 4 audio-recorded clinic encounters. They then completed either the ABIM Action Plan (control) or the online Study of Communication in Oncologist Patient Encounters (SCOPE) program (intervention). Oncologists collected another 25 CAHPS surveys and 4 audio-recorded encounters as follow-up. RESULTS: We enrolled 146 oncologists in the study. Only 27 completed the study; another 27 actively withdrew, and 94 did not complete the study. We identified four main challenges to participation: commitment discrepancies, burden of research, informed consent, and technology. We introduced efforts to overcome these barriers with success limited by time and resources. CONCLUSION: When conducting research in community practices, investigators must provide significant support, limit burden, increase flexibility, and conduct thorough pilot testing. PRACTICE IMPLICATIONS: To improve patient care, research must translate well into the workflow of actual practices. Assessing our experience, we identified challenges and effective solutions to be used by investigators as they plan and implement future communication interventions.

Mechanism of visual network dysfunction in relapsing-remitting multiple sclerosis and its relation to cognition.

OBJECTIVE: To investigate if changes in brain network function and connectivity contribute to the abnormalities in visual event related potentials (ERP) in relapsing-remitting multiple sclerosis (RRMS), and explore their relation to a decrease in cognitive performance. METHODS: We evaluated 72 patients with RRMS and 89 healthy control subjects in a cross-sectional study. Visual ERP were generated using illusory and non-illusory stimuli and recorded using 21 EEG scalp electrodes. The measured activity was modelled using Dynamic Causal Modelling. The model network consisted of 4 symmetric nodes including the primary visual cortex (V1/V2) and the Lateral Occipital Complex. Patients and controls were tested with a neuropsychological test battery consisting of 18 cognitive tests covering six cognitive domains. RESULTS: We found reduced cortical connectivity in bottom-up and interhemispheric connections to the right lateral occipital complex in patients (p < 0.001). Furthermore, interhemispherical connections were related to cognitive dysfunction in several domains (attention, executive function, visual perception and organization, processing speed and global cognition) for patients (p < 0.05). No relation was seen between cortical network connectivity and cognitive function in the healthy control subjects. CONCLUSION: Changes in the functional connectivity to higher cortical regions provide a neurobiological explanation for the changes of the visual ERP in RRMS. SIGNIFICANCE: This study suggests that changes in connectivity to higher cortical regions partly explain visual network dysfunction in RRMS where a lower interhemispheric connectivity may contribute to impaired cognitive function.

The Association Between Maintaining American Board of Emergency Medicine Certification and State Medical Board Disciplinary Actions.

BACKGROUND: In certain medical specialties, board certification is associated with a lower risk of state medical board disciplinary actions. OBJECTIVE: The association between maintaining American Board of Emergency Medicine (ABEM) certification and state medical disciplinary actions had not been studied. This study was undertaken to determine if maintaining ABEM certification was associated with a lower risk of disciplinary action. METHODS: This investigation was a historical cohort study using Cox regression. Physicians who did not have a lapse in ABEM certification were compared with physicians who had a lapse to determine the risk of disciplinary action. Lapsing was determined at the expiration of the initial certificate. This study included all physicians who obtained initial ABEM certification from 1980-2005. Additional covariates of interest included the number of attempts on the ABEM Qualifying Examination (1 vs. >1), the geographic region of the physician's residence, and the country of medical school. RESULTS: There were 23,002 physicians in the study cohort. Of these, 3370 (14.7%) let their certification lapse after initial certification. There were 701 (3.0%) physicians with disciplinary events. Lapsed physicians had higher rates of disciplinary actions than physicians who did not lapse (6.4% vs. 2.5%). ABEM-certified physicians who did not lapse were significantly less likely to be disciplined as physicians who let their certificate lapse (hazard ratio 0.50 [95% confidence interval 0.42-0.59]). CONCLUSIONS: The absolute incidence of physicians with a disciplinary action in this study cohort was low (3.0%). Maintaining ABEM certification was associated with a lower risk of state medical board disciplinary actions.

Chronic schistosomiasis suppresses HIV-specific responses to DNA-MVA and MVA-gp140 Env vaccine regimens despite antihelminthic treatment and increases helminth-associated pathology in a mouse model.

Future HIV vaccines are expected to induce effective Th1 cell-mediated and Env-specific antibody responses that are necessary to offer protective immunity to HIV infection. However, HIV infections are highly prevalent in helminth endemic areas. Helminth infections induce polarised Th2 responses that may impair HIV vaccine-generated Th1 responses. In this study, we tested if Schistosoma mansoni (Sm) infection altered immune responses to SAAVI candidate HIV vaccines (DNA and MVA) and an HIV-1 gp140 Env protein vaccine (gp140) and whether parasite elimination by chemotherapy or the presence of Sm eggs (SmE) in the absence of active infection influenced the immunogenicity of these vaccines. In addition, we evaluated helminth-associated pathology in DNA and MVA vaccination groups. Mice were chronically infected with Sm and vaccinated with DNA+MVA in a prime+boost combination or MVA+gp140 in concurrent combination regimens. Some Sm-infected mice were treated with praziquantel (PZQ) prior to vaccinations. Other mice were inoculated with SmE before receiving vaccinations. Unvaccinated mice without Sm infection or SmE inoculation served as controls. HIV responses were evaluated in the blood and spleen while Sm-associated pathology was evaluated in the livers. Sm-infected mice had significantly lower magnitudes of HIV-specific cellular responses after vaccination with DNA+MVA or MVA+gp140 compared to uninfected control mice. Similarly, gp140 Env-specific antibody responses were significantly lower in vaccinated Sm-infected mice compared to controls. Treatment with PZQ partially restored cellular but not humoral immune responses in vaccinated Sm-infected mice. Gp140 Env-specific antibody responses were attenuated in mice that were inoculated with SmE compared to controls. Lastly, Sm-infected mice that were vaccinated with DNA+MVA displayed exacerbated liver pathology as indicated by larger granulomas and increased hepatosplenomegaly when compared with unvaccinated Sm-infected mice. This study shows that chronic schistosomiasis attenuates both HIV-specific T-cell and antibody responses and parasite elimination by chemotherapy may partially restore cellular but not antibody immunity, with additional data suggesting that the presence of SmE retained in the tissues after antihelminthic therapy contributes to lack of full immune restoration. Our data further suggest that helminthiasis may compromise HIV vaccine safety. Overall, these findings suggested a potential negative impact on future HIV vaccinations by helminthiasis in endemic areas.

The American Board of Internal Medicine Maintenance of Certification Examination and State Medical Board Disciplinary Actions: a Population Cohort Study.

BACKGROUND: Some have questioned whether successful performance in the American Board of Internal Medicine (ABIM) Maintenance of Certification (MOC) program is meaningful. The association of the ABIM Internal Medicine (IM) MOC examination with state medical board disciplinary actions is unknown. OBJECTIVE: To assess risk of disciplinary actions among general internists who did and did not pass the MOC examination within 10 years of initial certification. DESIGN: Historical population cohort study. PARTICIPANTS: The population of internists certified in internal medicine, but not a subspecialty, from 1990 through 2003 (n = 47,971). INTERVENTION: ABIM IM MOC examination. SETTING: General internal medicine in the USA. MAIN MEASURES: The primary outcome measure was time to disciplinary action assessed in association with whether the physician passed the ABIM IM MOC examination within 10 years of initial certification, adjusted for training, certification, demographic, and regulatory variables including state medical board Continuing Medical Education (CME) requirements. KEY RESULTS: The risk for discipline among physicians who did not pass the IM MOC examination within the 10 year requirement window was more than double than that of those who did pass the examination (adjusted HR 2.09; 95% CI, 1.83 to 2.39). Disciplinary actions did not vary by state CME requirements (adjusted HR 1.02; 95% CI, 0.94 to 1.16), but declined with increasing MOC examination scores (Kendall's tau-b coefficient = - 0.98 for trend, p < 0.001). Among disciplined physicians, actions were less severe among those passing the IM MOC examination within the 10-year requirement window than among those who did not pass the examination. CONCLUSIONS: Passing a periodic assessment of medical knowledge is associated with decreased state medical board disciplinary actions, an important quality outcome of relevance to patients and the profession.

Cervicocranial artery dissection and scuba diving: Is there a link or is it serendipity?

INTRODUCTION: Numerous reports have documented cervicocranial artery dissection (CCAD) associated with scuba diving. The question remains as to whether there are risk factors unique to scuba diving related to the occurrence of CCAD. OBJECTIVES: This article aims to perform an examination of the reported cases to demonstrate any commonality among the injured divers and association with known risk factors for CCAD. METHODS: A PubMed search was performed utilizing the key words: carotid artery dissection, dissection, arterial dissection, cranial artery dissection, scuba, diving, scuba diving. Articles including reports, reviews, trials, case series, and letters were considered. Each report was critically dissected for information specific to the dive itself and the diver and analyzed for similarities and consistency with known risks. RESULTS: Twelve (12) reports of CCAD associated with scuba diving were identified. Activities involved with scuba diving appear to be consistent with CCAD risk factors. It is unclear if hyperbaric stress and physiological changes during a dive present specific risk. Trauma - e.g., environmental protection and activities associated with diving - was identified as a common risk factor in all cases. Ten (10) cases involved arteries at anatomic sites commonly associated with dissections. Seven divers documented to have dive profiles suspicious of decompression sickness were identified. CONCLUSIONS: There appears to be a correlation with minor traumas that occur with diving and CCAD. The inconsistency of the dive-related specific information reported makes it impossible for investigation of hyperbaric stress-related risk factors for CCAD to be analyzed.