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Presents letters to the editor of the 2001 issue of the 'British Journal of Surgery.' Effect of colectomy on gastric emptying in idiopathic slow-transit constipation; Causes of polytetrafluoroethylene patch saphenoplasty re-recurrence; Factors influencing the outcome after surgery for fecal incontinence.

Background: There is limited knowledge regarding the impact of perioperative critical care on frequency of neurological imaging findings following esophageal atresia (EA) repair., Methods: This is a retrospective study of infants (n = 70) following EA repair at a single institution (2009-2020). Sex, gestational age at birth, type of surgical repair, underlying disease severity, and frequency of neurologic imaging findings were obtained. We quantified the length of postoperative pain/sedation treatment and anesthesia exposure in the first year of life. Data were presented as numerical sums and percentages, while associations were measured using Spearman's Rho., Results: Vertebral/spinal cord imaging was performed in all infants revealing abnormalities in 44% (31/70). Cranial/brain imaging findings were identified in 67% (22/33) of infants in the context of clinically indicated imaging (47%; 33/70). Long-gap EA patients (n = 16) received 10 times longer postoperative pain/sedation treatment and twice the anesthesia exposure compared with short-gap EA patients (n = 54). The frequency of neurologic imaging findings did not correlate with underlying disease severity scores, length of pain/sedation treatment, or cumulative anesthesia exposure. Lack of associations between clinical measures and imaging findings should be interpreted with caution given possible underestimation of cranial/brain findings., Conclusions: We propose that all infants with EA undergo brain imaging in addition to routine spinal imaging given the high burden of abnormal brain/cranial findings in our cohort. Quantification of pain/sedation and anesthesia exposure in long-gap EA patients could be used as indirect markers in future studies assessing the risk of neurological sequelae as evidenced by early abnormalities on brain imaging., (© 2023 Wiley Periodicals LLC.)

Objectives: To determine incidence of death in residential care facilities for people with disability in Ireland, primary cause of death, associations of facility characteristics and deaths, and to compare characteristics of deaths reported as expected and unexpected., Design: Descriptive cross-sectional study., Setting: All residential care facilities for people with disability operational in Ireland in 2019 and 2020 (n=1356)., Participants: n=9483 beds., Main Outcome Measures: All expected and unexpected deaths notified to the social services regulator. Cause of death as reported by the facility., Results: 395 death notifications were received in 2019 (n=189) and 2020 (n=206). 45% (n=178) were for unexpected deaths. Incidence of death per 1000 beds per year was 20.83 for all, 11.44 for expected and 9.39 for unexpected deaths. Respiratory disease was the most common cause of death, accounting for 38% (n=151) of all deaths. In adjusted negative binomial regression analysis, congregated settings versus non-congregated (incidence rate ratio (95% CI): 2.59 (1.80 to 3.73)) and higher bed numbers (highest vs lowest quartile) (4.02 (2.19 to 7.40)) were positively associated with mortality. There was also a positive n-shaped association with category of nursing staff-to-resident ratio when compared with zero nurses. Emergency services were contacted for 6% of expected deaths. Of the deaths reported as unexpected, 29% were receiving palliative care and 10.8% had a terminal illness., Conclusion: Although incidence of death was low, residents of congregated and larger settings had higher incidence of death than residents of other settings. This should be a consideration for practice and policy. Given the high contribution of respiratory diseases to deaths and the potential avoidability of these, there is a need for improved respiratory health management in this population. Nearly half of all deaths were reported as unexpected; however, overlap in the characteristics of expected and unexpected deaths highlights the need for clearer definitions., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Coronavirus disease 2019 (COVID-19) is a significant cause for intensive care unit (ICU) admission worldwide. Most COVID-19 infections are associated with lower respiratory abnormalities but it has been increasingly associated with extra-pulmonary manifestations. Guillain-Barre syndrome (GBS) is a rarely diagnosed but severe disease associated with COVID-19 infection. We describe the diagnostic process behind diagnosing GBS in an elderly male who developed acute-onset quadriparesis and respiratory muscle failure associated with severe COVID-19 pneumonia in a military ICU. A 69-year-old male was admitted to the ICU for acute hypoxemic respiratory failure due to COVID-19 pneumonia. He was subsequently intubated and treated with dexamethasone and remdesivir with improvement. On hospital day 32, the patient was extubated. Three days later, he developed acute, symmetric limb quadriparesis and respiratory muscle failure requiring reintubation. Analysis of his cerebrospinal fluid showed a cytoalbuminologic dissociation, and electromyography/nerve conduction study showed slowed nerve conduction velocity. These findings are consistent with GBS. Blood cultures, serum polymerase chain reaction testing, and clinical symptoms were not suggestive of other common pathogens causing his GBS. The patient's acute GBS in the setting of recent severe COVID-19 infection strongly suggests association between the two entities, as supported by a growing body of case literature. The patient was subjected to intravenous immunoglobulin treatment and was discharged with greatly improved strength in the upper and lower extremities. Our goal in describing this case is to highlight the need for providers to consider, accurately diagnose, and treat GBS as a consequence of severe COVID-19 infection., (Published by Oxford University Press on behalf of the Association of Military Surgeons of the United States 2021. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Background: Posttraumatic stress disorder (PTSD) has been linked to respiratory symptoms and functional limitations, but the mechanisms leading to this association are poorly defined., Research Question: What is the relationship between PTSD, lung function, and the cardiopulmonary response to exercise in combat veterans presenting with chronic respiratory symptoms?, Study Design and Methods: This study prospectively enrolled military service members with respiratory symptoms following deployment to southwest Asia. All participants underwent a comprehensive evaluation that included pulmonary function testing and cardiopulmonary exercise testing. Pulmonary function test variables and cardiopulmonary response to exercise were compared in subjects with and without PTSD by using multivariable linear regression to adjust for confounders., Results: A total of 303 participants were included (PTSD, n = 70; non-PTSD, n = 233). Those with PTSD had a greater frequency of current respiratory symptoms. There were no differences in measures for airway disease or lung volumes, but patients with PTSD had a reduction in diffusing capacity that was eliminated following adjustment for differences in hemoglobin levels. Participants with PTSD had a lower anaerobic threshold (23.9 vs 26.4 cc/kg per minute; P = .004), peak oxygen pulse (19.7 vs 18.5 cc/beat; P = .03), and peak oxygen uptake (34.5 vs 38.8 cc/kg per minute; P < .001). No significant difference was observed in gas exchange, respiratory reserve, or effort at peak exercise between participants with and without PTSD., Interpretation: A diagnosis of PTSD was associated with a reduced anaerobic threshold, oxygen pulse, and peak oxygen uptake. This objective reduction in cardiopulmonary work is independent of baseline lung function, was not associated with abnormalities in gas exchange or respiratory reserve, and may be related to deconditioning., (Copyright © 2021 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

The National Heart, Lung, and Blood Institute has developed a strategic approach to fostering diversity and inclusion within its community of small business innovators. The approach is focused on three central goals: 1) Increase awareness of NHLBI's support for small businesses among underrepresented groups through focused outreach; 2) Identify and eliminate barriers to entry into small business funding programs and entrepreneurial activities for minority and female applicants through specific, targeted training and support; and 3) Expand diversity and inclusivity within our networks by providing additional support for NHLBI-funded small businesses to hire members of underrepresented groups. Key partnerships with biomedical accelerators in underserved regions will be leveraged to maximize impact and achieve all three goals. This article describes the historical context and current state of policies in this arena; it also provides details about mechanisms and approaches used to achieve the goals., Competing Interests: Competing Interests: None declared.

In specialty clinics, a staff physician is often required to direct patient flow through the clinic and performs all documentation for coding/billing. In response to the workload created by increased patient volume, many specialty clinics have implemented protocols for both disease treatment and coordination of clinic flow. In this article, we review the literature on using mobile technology to assist with patient care, clinic flow, disease treatment, and documentation/billing. We also describe the development and implementation of a mobile application in our pulmonary clinic designed to automate patient flow, assist the physician in documentation/billing, and gather research data including review of initial user data and lessons learned., (Published by Elsevier Inc.)

Integration of the sphenoid and ethmoid bones during early postnatal development is poorly described in the literature. A uniquely prolonged patency of sphenoethmoidal synchondrosis or prespheno-septal synchondrosis (PSept) has been attributed to humans. However, the sphenoethmoidal junction has not been studied using a comparative primate sample. Here, we examined development of the sphenoethmoidal interface using ontogenetic samples of Old and New World monkeys, strepsirrhine primates (lemurs and lorises), and a comparative sample of other mammals. Specimens ranging from late fetal to 1 month postnatal age were studied using histology, immunohistochemistry, and micro-computed tomography methods. Our results demonstrate that humans are not unique in anterior cranial base growth at PSept, as it is patent in all newborn primates. We found two distinctions within our sample. First, nearly all primates exhibit an earlier breakdown of the nasal capsule cartilage that abuts the orbitosphenoid when compared to nonprimates. This may facilitate earlier postnatal integration of the basicranium and midface and may enhance morphological plasticity in the region. Second, the PSept exhibits a basic dichotomy between strepsirrhines and monkeys. In strepsirrhines, the PSept has proliferating chondrocytes that are primarily oriented in a longitudinal plane, as in other mammals. In contrast, monkeys have a convex anterior end of the presphenoid with a radial boundary of cartilaginous growth at PSept. Our findings suggest that the PSept acts as a "pacemaker" of longitudinal facial growth in mammals with relatively long snouts, but may also contribute to facial height and produce a relatively taller midface in anthropoid primates. Anat Rec, 300:2115-2137, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Background: The STOPBANG questionnaire is used to predict the presence of obstructive sleep apnea (OSA). We sought to assess the performance of the STOPBANG questionnaire in younger, thinner patients referred to a sleep medicine clinic., Methods: We applied the STOPBANG questionnaire to patients referred for level I polysomnography (PSG) at our sleep center. We calculated likelihood ratios and area under the receiver operator characteristic (AUROC) curve and performed sensitivity analyses., Results: We performed our analysis on 338 patients referred for PSG. Only 17.2% (n = 58) were above age 50 years, and 30.5 and 6.8% had a BMI above 30 and 35 years, respectively. The mean apnea-hypopnea index (AHI) was 12.9 ± 16.4 and 63.9% had an AHI ≥5. The STOPBANG (threshold ≥3) identified 83.1% of patients as high risk for an AHI ≥5, and sensitivity, specificity, positive (PPV), and negative predictive values (NPV) were 83.8, 18.0, 64.4, and 38.0%, respectively. Positive and negative likelihood ratios were poor at 1.02-1.11 and 0.55-0.90, respectively, across AHI thresholds (AHI ≥5, AHI ≥15 and AHI ≥30), and AUROCs were 0.52 (AHI ≥5) and 0.56 (AHI ≥15). Sensitivity analyses adjusting for insomnia, combat deployment, traumatic brain injury, post-traumatic stress disorder, clinically significant OSA (ESS >10 and/or co-morbid disease), and obesity did not significantly alter STOPBANG performance., Conclusions: In a younger, thinner population with predominantly mild-to-moderate OSA, the STOPBANG Score does not accurately predict the presence of obstructive sleep apnea.

Objectives: A recently proposed nomogram is an attempt to define the subset of acetabular fractures at risk for primary total hip arthroplasty (THA) within 2 years of open reduction and internal fixation (ORIF). Our objectives were to determine whether this nomogram provides information adequate to reliably (1) prognosticate outcome within 2 years after ORIF or (2) identify optimal initial treatment choice (THA vs. ORIF) for patients with a posterior wall fracture., Design: Retrospective case series., Setting: University level 1 Trauma Center., Patients: From a database of consecutive posterior wall fractures treated by ORIF, 103 patients were identified for analysis: 6 with an unsatisfactory result at less than 2 years and 97 followed 2-14 years., Intervention: Calculation of percent risk of requiring THA within 2 years using the nomogram., Main Outcome Measurements: Comparison of this percent risk to the actual clinical outcome within 2 years after ORIF, measured in 2 ways: (1) THA performed (5 patients) and (2) overall unsatisfactory hip function determined by the modified Merle d'Aubigné score (9 patients total: the 5 with THA plus 4 additional without THA but having unsatisfactory hip function)., Results: The calculated percent risk ranged widely, with much overlap among patients having satisfactory or unsatisfactory results of ORIF. Statistical analysis did not yield a clinically useful positive predictive value: 0.25 [95% confidence interval (CI), 0.08-0.53] for THA and 0.44 (95% CI, 0.21-0.69) for an overall unsatisfactory clinical result., Conclusions: The acetabular fracture prognostic nomogram in its current form does not provide sufficient information to prognosticate outcome after ORIF or to determine appropriate surgical management for posterior wall fractures., Level of Evidence: Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

The sit-and-reach test (SRT) has been included in standard fitness test batteries for decades, but empirical evidence of actual muscle activity has been lacking. Furthermore, the positioning of the ankle joint during the execution of this test has received relatively scant attention. Therefore, the purpose of this investigation was to compare surface electromyographic (sEMG) activity of selected lower extremity and back musculature and examine the impact of ankle positioning during the standard SRT and the modified sit-and-reach test (MSRT). Seven male and 7 female subjects performed 3 trials of the SRT and MSRT, each in a dorsiflexed and plantar flexed ankle position. During all trials, muscle activity (sEMG) was measured from the right semimembranous (SM), erector spinae (ES), and gastrocnemius (G). Mean sEMG data from each muscle (SM, ES, and G) were normalized by being expressed as a percent contribution to the total electrical activity (100%). Surface electromyographic activity data were also used to determine muscle activation ratios (e.g., SM to ES). Results revealed significantly higher flexibility scores during the plantar flexion condition for both test modalities. The SM exhibited the greatest percent contribution to total sEMG activity within all testing conditions. The SM to G and SM to ES muscle activation ratios were significantly greater than their inverse counterparts within all 4 testing conditions. Based on the 2 sEMG analysis techniques, the SM seemed to exhibit the greatest muscle activity. This investigation provides direct evidence of sEMG muscle activity during the SRT and MSRT, further confirming these tests to be a valid measure of hamstring flexibility.

Purpose: The Argus II epiretinal prosthesis has been developed to provide partial restoration of vision to subjects blinded from outer retinal degenerative disease. Participants were surgically implanted with the system in the United States and Europe in a single arm, prospective, multicenter clinical trial. The purpose of this investigation was to determine which factors affect electrical thresholds in order to inform surgical placement of the device., Methods: Electrode-retina and electrode-fovea distances were determined using SD-OCT and fundus photography, respectively. Perceptual threshold to electrical stimulation of electrodes was measured using custom developed software, in which current amplitude was varied until the threshold was found. Full field stimulus light threshold was measured using the Espion D-FST test. Relationships between electrical threshold and these three explanatory variables (electrode-retina distance, electrode-fovea distance, and monocular light threshold) were quantified using regression., Results: Regression analysis showed a significant correlation between electrical threshold and electrode-retina distance ( R 2 = 0.50, P = 0.0002; n = 703 electrodes). 90.3% of electrodes in contact with the macula ( n = 207) elicited percepts at charge densities less than 1 mC/cm 2 /phase. These threshold data also correlated well with ganglion cell density profile ( P = 0.03). A weaker, but still significant, inverse correlation was found between light threshold and electrical threshold ( R 2 < 0.52, P = 0.01). Multivariate modeling indicated that electrode-retina distance and light threshold are highly predictive of electrode threshold ( R 2 = 0.87; P < 0.0005)., Conclusions: Taken together, these results suggest that while light threshold should be used to inform patient selection, macular contact of the array is paramount., Translational Relevance: Reported Argus II clinical study results are in good agreement with prior in vitro and in vivo studies, and support the development of higher-density systems that employ smaller diameter electrodes. (clinicaltrials.gov identifier: NCT00407602).

Objective: To investigate the ability of 28 blind subjects implanted with a 60-electrode Argus II (Second Sight Medical Products Inc) retinal prosthesis system to detect the direction of a moving object., Methods: Blind subjects (bare light perception or worse in both eyes) with retinitis pigmentosa were implanted with the Argus II prosthesis as part of a phase 1/2 feasibility study at multiple clinical sites worldwide. The experiment measured their ability to detect the direction of motion of a high-contrast moving bar on a flatscreen monitor in 3 conditions: with the prosthesis system on and a 1-to-1 mapping of spatial information, with the system off, and with the system on but with randomly scrambled spatial information., Results: Fifteen subjects (54%) were able to perform the task significantly better with their prosthesis system than they were with their residual vision, 2 subjects had significantly better performance with their residual vision, and no difference was found for 11 subjects. Of the 15 better-performing subjects, 11 were available for follow-up testing, and 10 of them had significantly better performance with normal rather than with scrambled spatial information., Conclusions: This work demonstrates that blind subjects implanted with the Argus II retinal prosthesis were able to perform a motion detection task they could not do with their native vision, confirming that electrical stimulation of the retina provides spatial information from synchronized activation of multiple electrodes., Trial Registration: clinicaltrials.gov Identifier:NCT00407602

Background: Laparoscopic sleeve gastrectomy (LSG) has rapidly gained popularity as a definitive bariatric procedure despite the sparse long-term follow-up data. On the basis of extensive experience with the open Magenstrasse and Mill operation, we began practice of LSG in 2000. The objective of the present study was to analyze 8-9 years of our follow-up data for LSG at a university hospital in the United Kingdom., Methods: From January 2000 to December 2001, 20 patients underwent LSG. A 32F bougie was used for calibration in all cases., Results: The preoperative median body mass index was 45.8 kg/m(2) (range 35.8-63.7), and 9 patients (45%) were superobese (body mass index ≥ 50 kg/m(2)). For LSG as a definitive bariatric procedure, 8-9-year follow-up data were available for 13 patients. Of the remainder, 4 patients underwent revision surgery and 3 were lost to follow-up after 2 years. For the entire cohort, the median excess weight loss (EWL) was 73% (range 13-105%) at 1 year, 78% (range 22-98%) at 2 years, 73% (range 28-90%) at 3 years, and 68% (range 18-85%) at 8 or 9 years (P = .074). Of the 13 LSG-only patients with 8-9 years of follow-up, 11 (55% of the starting cohort) had >50% EWL at 8 or 9 years. No significant difference was found in the initial body mass index between the LSG-only patients with >50% EWL and others (45.9 kg/m(2), range 35.8-59.4 versus 45.7 kg/m(2), range 38.9-63.7, respectively; P = .70). The LSG-only patients with >50% EWL had a marginally significantly greater EWL at 1 year compared with the others (76%, range 48-103% versus 45%, range 13-99%, respectively; P = .058)., Conclusion: At 8-9 years of follow-up, 55% of patients had >50% EWL from LSG as a definitive bariatric procedure., (Copyright © 2012 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

We reevaluate the predictive accuracy of intravascular ultrasound (IVUS)-derived per cent plaque area stenosis (PAS) in significant coronary lesions (CLs) with or without proximal and distal reference vessel area adjustment. IVUS is valuable in defining moderate CL severity (30 to 70%) in left main (LM) or non-left main (NLM) coronaries using minimum luminal area (MLA) of ≤5.9 and ≤4 mm(2), respectively. Despite a strong correlation with severe CLs, PAS (≥ 70% for NLM and ≥67% for LM) remains underutilized because of confusion about an appropriate reference standard. We studied 120 patients with symptomatic moderate CLs (74 NLM, 46 LM) who underwent IVUS. In-lesion and adjusted PAS were derived by subtracting MLA from in-lesion and proximal or distal reference's external elastic membrane (EEM) area, respectively, divided by corresponding EEM area multiplied by 100. In-lesion PAS was correlated with MLA cutoffs of ≤5.9 and ≤7.5 mm(2) for LM and ≤4 mm(2) for NLM. Adjusted PAS strongly correlated with in-lesion PAS irrespective of reference segment (proximal reference, r = 0.879, p < 0.001; distal reference, r = 0.833, p < 0.001; mean proximal and distal reference, r = 0.896, p < 0.001). Considering MLA of ≤4 mm(2) (for NLM) and ≤5.9 mm(2) (for LM), in-lesion PAS of ≥70 and ≥67%, respectively, explained the majority of severe CLs but the sensitive LM MLA cutoff of ≤7.5 mm(2) showed higher predictive accuracy. Based on results, both in-lesion PAS and adjusted PAS can be used interchangeably and correlate strongly with MLA.

Background: This study aimed to evaluate the role of the Obesity Surgery Mortality Risk Score (OS-MRS) to predict the risk of post-operative adverse events, in addition to death, from any laparoscopic bariatric procedure., Methods: The OS-MRS was applied to consecutive patients at a single hospital during October 2008-September 2009. The composite end point comprised one or more of the following adverse events: mortality, re-intervention, re-admission to hospital, venous thromboemobolism, or blood transfusion., Results: There were 381 patients (men, 19%). The median age was 43 years (range, 19-67 years), with 42% patients aged ≥45 years. The median weight was 126 kg (75-295 kg) and median BMI 46 kg/m(2) (30-84 kg/m(2)); 37% had BMI ≥50 kg/m(2). Twenty-seven percent of patients had hypertension and 3% had a past history of venous thromboembolism. The OS-MRS classes were A (60.1%), B (35.9%), or C (4.0%). Operations comprised adjustable gastric band (37%), Roux-en-Y gastric bypass (54%), sleeve gastrectomy (8%), or biliopancreatic diversion (1%). Of the operations, 1.6% were revisional procedures. An adverse outcome occurred in 19 patients, with distribution in 3.5% of class A patients, 5.8% of class B, and 20.0% of class C (A vs. B, P = 0.451; A vs. C, P = 0.002; B vs. C, P = 0.025). There was one death: OS-MRS class C. On multivariate analysis, OS-MRS (class C vs. A or B; Odds Ratio [OR], 4; P = 0.050) and type of operation (band vs. bypass or sleeve; OR, 9.2; P = 0.033) were independently predictive of the composite end point., Conclusion: OS-MRS and type of the bariatric operation are independently predictive of the risk of post-operative adverse events.

Chronic pancreatitis is a progressive fibroinflammatory disease that exists in large-duct (often with intraductal calculi) or small-duct form. In many patients this disease results from a complex mix of environmental (eg, alcohol, cigarettes, and occupational chemicals) and genetic factors (eg, mutation in a trypsin-controlling gene or the cystic fibrosis transmembrane conductance regulator); a few patients have hereditary or autoimmune disease. Pain in the form of recurrent attacks of pancreatitis (representing paralysis of apical exocytosis in acinar cells) or constant and disabling pain is usually the main symptom. Management of the pain is mainly empirical, involving potent analgesics, duct drainage by endoscopic or surgical means, and partial or total pancreatectomy. However, steroids rapidly reduce symptoms in patients with autoimmune pancreatitis, and micronutrient therapy to correct electrophilic stress is emerging as a promising treatment in the other patients. Steatorrhoea, diabetes, local complications, and psychosocial issues associated with the disease are additional therapeutic challenges., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background/aims: To determine to what extent subjects implanted with the Argus II retinal prosthesis can improve performance compared with residual native vision in a spatial-motor task., Methods: High-contrast square stimuli (5.85 cm sides) were displayed in random locations on a 19″ (48.3 cm) touch screen monitor located 12″ (30.5 cm) in front of the subject. Subjects were instructed to locate and touch the square centre with the system on and then off (40 trials each). The coordinates of the square centre and location touched were recorded., Results: Ninety-six percent (26/27) of subjects showed a significant improvement in accuracy and 93% (25/27) show a significant improvement in repeatability with the system on compared with off (p<0.05, Student t test). A group of five subjects that had both accuracy and repeatability values <250 pixels (7.4 cm) with the system off (ie, using only their residual vision) was significantly more accurate and repeatable than the remainder of the cohort (p<0.01). Of this group, four subjects showed a significant improvement in both accuracy and repeatability with the system on., Conclusion: In a study on the largest cohort of visual prosthesis recipients to date, we found that artificial vision augments information from existing vision in a spatial-motor task. Clinical trials registry no NCT00407602.

Purpose: With the goal of eventually restoring functional vision in patients with retinal degenerative diseases, USC/Second Sight Medical Products, Inc. chronically implanted blind human subjects with a prototype epiretinal prosthesis consisting of a 4 x 4 array of 16 stimulating electrodes. To accurately represent a visual scene, a visual prosthesis must convey luminance information across a range of brightness levels. To achieve this, the brightness of phosphenes produced by an individual electrode should scale appropriately with luminance, and the same luminance should produce equivalently bright phosphenes across the entire electrode array. The goal was to examine how apparent brightness changes as a function of stimulation intensity across electrodes., Methods: As described in previous studies, electrical stimulation of intact cells of the neural retina using this prosthetic device reliably elicits visual percepts in human subjects blinded by retinitis pigmentosa. Here, apparent brightness for a range of electrical amplitudes was measured using both subjective magnitude rating and brightness-matching procedures in chronically implanted human subjects., Results: It was found that apparent brightness can be described as a power function of stimulation intensity. The same model can also predict brightness matching across electrodes., Conclusions: These results suggest that a relatively simple model for scaling current across electrodes may be capable of producing equivalently bright phosphenes across an entire array. (ClinicalTrials.gov number, NCT00279500.).

Background: Conventional ultrasonically activated devices use linear mode vibration. Torsional mode ultrasonically activated device (TM) that oscillate around an arc have been recently introduced in the hope that the design may result in faster cutting and better hemostasis., Methods: Patients undergoing elective laparoscopic cholecystectomy were randomized to TM or linear mode ultrasonically activated device (LM). Intraoperative events were recorded. Postoperatively, a sample of suction fluid was analyzed for hemoglobin concentration to calculate intraoperative blood loss., Results: Seventy-five patients were randomized to TM and 76 patients to LM. Median blood loss was 5 (interquartile range (IQR), 1-19.7) ml with TM and 10.5 (IQR, 2.3-23) ml with LM (p = 0.105). The 95% confidence interval for the difference in median operative blood loss was -1.3 to +9.5 ml. Median gallbladder dissection time was similar in both groups (17 (IQR 11-29) minutes for TM vs. 21 (IQR, 12-29) minutes for LM; p = 0.248). Other modalities of hemostasis were required in 14 patients (19%) in the TM group compared with 21 patients (28%) in the LM group. One patient in the LM group developed postoperative hemoperitoneum and required urgent laparoscopic exploration. No patient required blood transfusion or suffered any other significant complication., Conclusion: TM has similar effectiveness to LM for laparoscopic cholecystectomy., Registration Number: ISRCTN87527062 ( http://www.controlled-trials.com ).

Objective: To demonstrate that an epiretinal prosthesis can produce patterned visual perception in patients blinded by photoreceptor degeneration who have no other treatment options., Methods: A totally blind subject with retinitis pigmentosa had a 16-electrode epiretinal prosthesis implanted. The implant is controlled wirelessly by an external computer or a head-mounted video camera. Spatial vision was assessed by measuring the subject's response to direct stimulation of patterns and by comparing the ability of the subject to identify the orientation of gratings with the system on and off., Results: In response to stimulation of 2 orthogonal rows of electrodes, the subject drew 2 lines with a mean (SEM) angle of 87.4 degrees (1.8 degrees) between them. With the system on, the subject identified the orientation of the grating target up to a spatial resolution that matches the spacing between the adjacent electrodes. In contrast, with the system off, the subject could not detect or identify the target's orientation., Conclusion: Synchronized stimulation of different retinal locations with an epiretinal prosthesis implanted long-term can produce spatial vision with an acuity level determined by the distance between the electrodes., Trial Registration: clinicaltrials.gov Identifier: NCT00279500.

Purpose: With the long-term goal of restoring functional vision in patients with retinal degenerative diseases, the eyes of blind human subjects were implanted chronically with epiretinal prostheses consisting of two-dimensional electrode arrays that directly stimulated cells of the neural retina., Methods: Psychophysical techniques were used to measure the brightness of electrically generated percepts on single electrodes using a variety of electrical stimulation patterns., Results: It was possible to predict the sensitivity of the human visual system to a wide variety of retinal electrical stimulation patterns using a simple and biologically plausible model., Conclusions: This is the first study to demonstrate that, on the single-electrode level, retinal electrical stimulation in humans can produce visual qualia that are predictable using a quantitative model, a prerequisite for a successful retinal prosthesis. (ClinicalTrials.gov number, NCT00279500.).

The Argus II 60 channel epiretinal prosthesis has been developed in order to provide partial restoration of vision to subjects blinded from outer retinal degenerative disease. To date the device has been implanted in 21 subjects as part of a feasibility study. In 6 month post-implantation door finding and line tracking orientation and mobility testing, subjects have shown improvements of 86% and 73%, respectively, for system on vs. system off. In high-contrast Square Localization tests using a touch screen monitor 87% of tested subjects performed significantly better with the system on compared with off. These preliminary results show that the Argus II system provides some functional vision to blind subjects.

Background: Torsional mode ultrasonic coagulating shears are an alternative device to linear mode shears for hemostatic cutting. The aim of this study was to compare the vessel-sealing quality of torsional and linear mode ultrasonic coagulating shears on human veins., Materials and Methods: Veins were harvested from 15 patients during varicose vein surgery. Each vessel was sealed and cut by both devices at different sites. The seals were either tested for burst pressure or examined microscopically to compare mural thickness, seal length, and extent of coagulation and lateral thermal effect., Results: For veins 2.0-3.0 mm in diameter, the median burst pressure was higher on seals made with torsional mode shears (245, IQR 161-360 mm Hg vs. 133, IQR 101-165 mm Hg; P = 0.001). Similarly, for veins 3.5-4.5 mm in diameter, the median burst pressure was higher with torsional mode shears (149, IQR 118-212 mm Hg vs. 94, IQR 82-126 mm Hg; P = 0.001). There was no significant difference in the median burst pressure for veins 5.0-6.0 mm in diameter (82, IQR 61-132 mm Hg vs. 76, IQR 40-114 mm Hg; P = 0.268). Seals made with torsional mode shears showed significantly greater seal length (517 +/- 300 microm vs. 316 +/- 147 microm; P = 0.016), more tissue coagulation (467 +/- 197 microm vs. 335 +/- 128 microm; P = 0.015), and greater lateral thermal effect (1479 +/- 340 microm vs. 1116 +/- 253 mum; P < 0.001)., Conclusion: Torsional mode ultrasonic shears produced more secure seals on veins up to 4.5 mm in diameter. This can be explained by the greater seal length produced by torsional mode shears.

Background: Obesity predisposes to incisional herniation and increased the incidence of recurrence after conventional open repair. Only sparse data on the safety and security of laparoscopic ventral hernia repair (LVHR) for morbidly obese patients are available. This study compared the incidence of perioperative complications and early recurrence after LVHR between morbidly obese and non-morbidly obese patients., Methods: The case records of consecutive patients who underwent LVHR between December 2002 and August 2007 were reviewed. Patients with a body mass index (BMI) lower than 35 kg/m2 were compared with morbidly obesity patients who had a BMI of 35 kg/m2 or higher., Results: The study included 168 patients (87 men) with a median age of 55 years (range, 24-92 years). Two conversions to open repair (1.2%) were performed, both for non-morbidly obese patients. Of the 168 patients, 42 (25%) were morbidly obese (BMI range, 35.0-58.0 kg/m2) and 126 (75%) were non-morbidly obese (BMI range, 15.5-34.9 kg/m2). The groups showed no significant differences in age, gender, number or size of fascial defects, operative time, length of hospital stay, or incidence of perioperative complications. At a median follow-up period of 19 months (range, 6-62 months), 20 patients (12%) had recurrent hernias. The incidence of recurrence was significantly associated with the size of the fascial defect and the size of the mesh, but not with morbid obesity., Conclusion: No significant difference in the incidence of perioperative complications or recurrence after LVHR was observed between the morbidly obese patients and the non-morbidly obese patients.

Sulfate reducing bacteria (SRB) are commonly used in environmental bioprocesses for the treatment of acid mine drainage and sulfate wastewaters. Biogenic H(2)S is also a potential source of H(2) fuel with the recent development of H(2)S splitting technologies. In this study, a sulfate reducing packed bed bioreactor (PBR) capable of rapidly achieving high volumetric productivities was developed using a novel method of rational inoculum design and the selection of improved biomass carrier materials. An inoculum with initial composition of approximately 95% Desulfovibrio desulfuricans (ATCC 7757) and 5% SRB consortium was designed based on the pure strain's superior immobilization potential and the SRB consortium's superior kinetics. Diatomaceous earth (DE) pellets, porous glass beads, polyurethane foam and bone char were evaluated as potential biomass carrier materials. The DE pellets immobilized the most biomass and were employed in two packed bed bioreactor fermentations. Using the designed inoculum and DE pellets, a packed bed bioreactor achieved a volumetric productivity of 493 mol H(2)S m(-3) day(-1) (based on a 308 mL working volume) with a dissolved sulfide concentration of 9.9 mM. This occurred after 8.3 days of operation and represents a tenfold reduction in the start-up period compared to other sulfate reducing PBRs described in the literature., ((c) 2008 Wiley Periodicals, Inc.)

Purpose: The goal was to evaluate how perceptual thresholds are related to electrode impedance, electrode size, the distance of electrodes from the retinal surface, and retinal thickness in six subjects blind as a result of retinitis pigmentosa, who received epiretinal prostheses implanted monocularly as part of a U.S. Food and Drug Administration (FDA)-approved clinical trial., Methods: The implant consisted of an extraocular unit containing electronics for wireless data, power recovery, and generation of stimulus current, and an intraocular unit containing 16 platinum stimulating electrodes (260- or 520-microm diameter) arranged in a 4 x 4 pattern. The electrode array was held onto the retina by a small tack. Stimulation was controlled by a computer-based external system that allowed independent control over each electrode. Perceptual thresholds (the current necessary to see a percept on 79% of trials) and impedance were measured for each electrode on a biweekly basis. The distance of electrodes from the retinal surface and retinal thickness were measured by optical coherence tomography on a less regular basis., Results: Stimulation thresholds for detecting phosphenes correlated with the distance of the electrodes from the retinal surface, but not with electrode size, electrode impedance, or retinal thickness., Conclusions: Maintaining close proximity between the electrode array and the retinal surface is critical in developing a successful retinal implant. With the development of chronic electrode arrays that are stable and flush on the retinal surface, it is likely that the influence of other factors such as electrode size, retinal degeneration, and subject age will become more apparent. (ClinicalTrials.gov number, NCT00279500.).

An N(2) strip gas was used in a packed bed sulfate-reducing bioreactor to recover the dissolved sulfide product and improve sulfate conversion. The highest volumetric productivity obtained was 261 mol H(2)S m(-3) d(-1). Lowering the initial pH of the medium from 7 to 6 increased the H(2)S content of the strip gas from 3.6 to 5.8 mol%. The ratio of strip gas to liquid flow rates (G/L) was found be to a suitable basis for scaling the process. Calculations indicated that modest G/L values (<10(2)) were required to recover the residual dissolved sulfide in a downstream stripping column.

A retinal prosthesis system to restore sight for the blind is under development. The system is analogous to cochlear implants, in which photoreceptor input is bypassed and replaced by direct electrical stimulation of the retinal ganglion cells. Currently, six test subjects have been implanted with a 4x4 electrode array and stimulator. We report here psychophysical clinical data examining how stimulation amplitude affects phosphene shape and repeatability on a single electrode. Phosphene shape data was quantified by a set of numerical descriptors calculated from image moments. Comparison of phosphene descriptors for a single electrode across repeated trials and amplitude levels measured the repeatability within an amplitude group. Our experimental findings show that stimulation of the retina creates repeatable percept shapes and that an increase in stimulation amplitude causes a significant change in size and shape of phosphenes.

Hepatocellular carcinoma is the most common primary tumour of the liver. Metastasis is frequent in these aggressive tumours and is commonly to the lungs, regional lymph nodes, or bone. Metastasis as a discrete subcutaneous nodule has not been described before. We report a case of hepatocellular carcinoma with a solitary subcutaneous metastatic deposit identified 18 months after the initial hepatic surgery.