Laparoscopic partial splenectomy in distal pancreatectomy may preserve splenic function.

INTRODUCTION: Splenectomy is known to carry a risk of infection with encapsulated organisms and associated sepsis. Current Australian guidelines recommend intensive vaccination schedules and long-term antibiotic therapy. We postulate that in some clinical scenarios where distal pancreatectomy (DP) and splenectomy is being performed, a partial splenectomy is feasible. This may preserve splenic function and help retain immunocompetence. METHODS: Five patients underwent laparoscopic distal pancreatectomy with partial splenectomy (LDPPS). The DP is performed with proximal division and resection of the splenic artery and vein. The inferior portion of the spleen is removed en bloc with the distal pancreas with ligasure and linear cutting staplers. The line of demarcation on the spleen after the division of the splenic artery identifies the portion supplied by the short gastric vessels. Temporary clamping of the short gastrics during splenic parenchymal transection reduces blood loss. All operations were completed laparoscopically and within 4 h. RESULTS: The pathology of resected lesions includes a serous cystadenoma, a pseudocyst, an IPMN and two small medial pancreatic ductal adenocarcinomas. The benign lesions involved splenic vessels at the hilum, making Kimura or Warshaw procedures untenable. No patient required blood transfusion. One patient suffered a postoperative collection consistent with postoperative pancreatic fistula requiring a drain for 10 days. Follow-up ranged from 6 to 24 months. Following surgery, all patients had a perfused splenic remnant on imaging and benign blood films, which suggests retained splenic function. CONCLUSION: Preserving some spleen when performing distal pancreatectomy may provide long-term benefits for patients.

How to do laparoscopic repair of perforated anterior duodenal ulcers: a 'three arches' falciform patch technique simplifies the approach.

Laparoscopic repair of perforated duodenal ulcers has proven superior results to open procedures though uptake has been poor. We describe the 'three arches' technique as a means of reducing technical difficulty and improving operative efficiency. Our case series of patients undergoing this technique for perforated peptic ulcer disease demonstrates comparable results to other methods of repair.

Are the screening guidelines for branch duct intraductal papillary mucinous neoplasms cost-effective in an Australian setting?

BACKGROUNDS: Intraductal papillary mucinous neoplasms (IPMN) are cystic neoplasms of the pancreatic ductal system. These incidental cystic lesions are increasingly found on radiological imaging and screened for malignant transformation. The Fukuoka consensus guidelines recommend screening with computed tomography, magnetic resonance imaging or endoscopic ultrasound. Branch duct IPMN (BD-IPMN) have significantly lower malignancy and mortality rates compared to main duct IPMN. Our aim was to assess the cost-effectiveness of guideline's recommendations for BD-IPMN screening of cysts between 2 and 3 cm in an Australian context. METHODS: Markov model decision analysis was used to calculate the incremental cost-effectiveness ratio (ICER) of screening. The ICER was compared to a willingness to pay (WTP) threshold of $50 000. We performed scenario analysis to examine the effect of cyst size and non-linearity of malignancy rate on ICER. Probabilistic sensitivity analyses (PSA) were performed on our input parameters. RESULTS: Screening resulted in 586 quality adjusted life years gained and a net present value of $20 379 939, resulting in a base-case ICER of $34 758. After scenario analysis for non-linearity of malignancy rate the ICER increases to $64 555, which is above the WTP threshold. PSA indicates that ICER is most susceptible to the pre-test malignancy rate. CONCLUSION: This cost analysis demonstrates that screening of 2-3 cm BD-IPMN according to current guidelines is unlikely to be cost-effective in an Australian context. To determine the true ICER, a cost analysis on real-world data is required.

Acinar cystic transformation of the pancreas causing progressive main pancreatic duct dilation: a diagnostic dilemma.

Acinar cystic transformation (ACT) of the pancreas is a rare benign lesion. We describe a case of ACT with progressive main pancreatic duct dilation concerning for malignancy, not previously described. We discuss the difficulties associated with imaging and biopsy in differentiating this pathology from other cystic lesions, including intraductal mucinous papillary neoplasms.

Targeted surgical coaching can improve operative self-assessment ability: A single-blinded nonrandomized trial.

BACKGROUND: The aim of the study was to investigate the effect of targeted surgical coaching on self-assessment of laparoscopic operative skill. Accurate self-assessment is vital for autonomous professional development. Surgical coaching can be used for performance improvement, but its role in this domain has been insufficiently investigated. METHODS: This was a single site, nonrandomized, interrupted time series design trial. Participants were residents, fellows, and attending surgeons regularly performing laparoscopic general surgery operations. Each participant was enrolled in an individualized coaching program using review of personal and peer laparoscopic videos. The program involved 3 to 5 sessions over a period of 6 to 19 weeks. Coaching used case debriefing to target self-assessment proficiency, with a focus on objective interpretation of observations and facilitative capacity building. The primary outcome measure was self-assessment accuracy and correlation to expert ratings. The Objective Structured Assessment of Technical Skill global rating scale was utilized for evaluation. RESULTS: Twelve participants were recruited and completed the coaching program. At baseline, there was no correlation between self-assessment and expert ratings. After completion of the coaching program there was correlation between self-assessment and expert ratings (P = .003) and improved self-assessment accuracy compared to baseline (P = .041). CONCLUSION: This study has demonstrated that targeted coaching using video review of laparoscopic cases can improve operative self-assessment accuracy using the Objective Structured Assessment of Technical Skill.

Reformed gallbladder after laparoscopic subtotal cholecystectomy: correlation of surgical findings with ultrasound and CT imaging†.

Laparoscopic subtotal cholecystectomy is a technique that is becoming increasingly prevalent in modern surgery. It avoids the cystic duct and artery where acute or chronic cholecystitis prevents a safe laparoscopic dissection of these structures. There are numerous reports of symptomatic cystic duct remnants after subtotal cholecystectomy in the literature on post-cholecystectomy syndrome. We present a case report of a 62-year-old man who underwent emergent laparoscopic subtotal cholecystectomy complicated by the development of a persistent, controlled bile leak. This was followed on serial ultrasound examinations and managed with multiple drain insertions and endoscopic retrograde cholangiopancreatography. The patient represented 4 months later with right upper quadrant pain and was found to have an apparently normal gallbladder on CT abdomen. Repeat laparoscopic cholecystectomy demonstrated a reformed gallbladder wall and was completed in the standard fashion. This case demonstrates an unexpected complication of laparoscopic cholecystectomy with correlation of radiological and surgical findings.

Molecular phylogenetics of the allodapine bee genus Braunsapis: A-T bias and heterogeneous substitution parameters.

Extreme AT bias in Hymenopteran mitochondrial genes have created difficulties for molecular phylogenetic analyses, especially for older divergences where multiple substitutions can erode signal. Heterogeneity in the evolutionary rates of different codon positions and different genes also appears to have been a major problem in resolving ancient divergences in allodapine bees. Here we examine the phylogeny of relatively recent divergences in the allodapine bee genus Braunsapis. We examined heterogeneity in nucleotide substitution parameters for one nuclear gene and codon positions in two mitochondrial genes, exploring various phylogenetic analyses for recovering relationships among species from Africa, Madagascar, southern Asia, and Australia. We explored maximum parsimony, maximum likelihood, Log determinant and Bayesian analyses. Broad topological features of best fit trees tended to be similar for equivalent data sets (e.g., total, or with 3rd mt positions excluded), regardless of the analytic method used (e.g., maximum likelihood or Bayesian). Analyses that used the total data set without modelling partitions separately gave unlikely results, indicating that the Malagasy species was most closely related to Australian species. However, analyses that excluded 3rd mitochondrial positions, or modelled partitions separately, suggested that the Malagasy species falls within the African clade. The unlikely topologies apparently result from long branch attraction, and this problem is ameliorated where modelling allows more realistic estimates of base composition and evolutionary rates for 3rd mitochondrial positions. However, we found that even when codon positions are modelled separately, estimated evolutionary rates for 3rd mitochondrial positions are likely to underestimate true rates. Long branch attraction and multiple substitutions are likely to be much more difficult to circumvent in analyses that explore older, generic-level, divergences in allodapine bees where overwriting is expected to be much more extreme. Our results indicate an African origin for Braunsapis, followed by a single, very early, dispersal event into Asia and then by a later dispersal event into Australia. The Malagasy species is derived from within the African clade.

Phylogenetic divergence of the Australian allodapine bees (Hymenoptera: Apidae).

Allodapine bees are most diverse in Africa but are distributed throughout the Old World tropical and Austral regions. They are considered useful for studies into the evolution of social behaviour since they exhibit the full range of social organisation from solitary to highly eusocial (sensu; ). Five genera are found in Australia, namely Braunsapis, Exoneurella, Exoneura, Brevineura, and Inquilina. Sociality and life histories are well documented for the exoneurine genera (review in ) and Inquilina is an obligate social parasite of species of Exoneura (). In this paper, maximum parsimony and maximum likelihood methods using molecular sequence data from two mitochondrial gene regions (cyt b and COI) and a single nuclear gene region (EF-1alpha) are used to reconstruct phylogenetic relationships of the Australian allodapine genera. Results suggest that the exoneurine group (Brevineura, Exoneurella, and Exoneura+Inquilina) diverged very rapidly and are monophyletic to the exclusion of other (primarily African) allodapine genera. A clade containing Australian species of Braunsapis is also monophyletic to the exclusion of African congeners. Braunsapis is not phylogenetically close to, and is a more derived group than the exoneurine group and probably came to occupy the Australian plate via a later dispersal through the southern Asian region. It is unclear at this point how the exoneurine group came to occupy the Australian plate and possible scenarios are discussed.

Molecular phylogenetics of allodapine bees, with implications for the evolution of sociality and progressive rearing.

Allodapine bees have long been regarded as providing useful material for examining the origins of social behavior. Previous researchers have assumed that sociality arose within the Allodapini and have linked the evolution of sociality to a transition from mass provisioning to progressive provisioning of brood. Early phylogenetic studies of allodapines were based on morphological and life-history data, but critical aspects of these studies relied on small character sets, where the polarity and coding of characters is problematic. We used nucleotide sequence data from one nuclear and two mitochondrial gene fragments to examine phylogenetic structure among nine allodapine genera. Our data set comprised 1506 nucleotide positions, of which 402 were parsimony informative. Maximum parsimony, log determinant, and maximum likelihood analyses produced highly similar phylogenetic topologies, and all analyses indicated that the tropical African genus Macrogalea was the sister group to all other allodapines. This finding conflicts with that of previous studies, in which Compsomelissa + Halterapis formed the most basal group. Changing the basal node of the Allodapini has major consequences for understanding evolution in this tribe. Our results cast doubt on the previous hypotheses that progressive provisioning and castelike social behavior evolved among lineages leading to the extant allodapine taxa. Instead, our results suggest that mass provisioning in Halterapis is a derived feature and that social behavior is an ancestral trait for all allodapine lineages. The forms of social behavior present in extant allodapines are likely to have resulted from a long evolutionary history, which may help explain the complexity of social traits found in many allodapine bees.