Jerzy A. Walocha

Telocytes: new insight into the pathogenesis of gallstone disease

The major mechanisms of gallstone formation include biliary cholesterol hypersecretion, supersaturation and crystallization, mucus hypersecretion, gel formation and bile stasis. Gallbladder hypomotility seems to be a key event that triggers the precipitation of cholesterol microcrystals from supersaturated lithogenic bile. Telocytes, a new type of interstitial cells, have been recently identified in many organs, including gallbladder. Considering telocyte functions, it is presumed that these cells might be involved in the signalling processes. The purpose of this study was to correlate the quantity of telocytes in the gallbladder with the lithogenicity of bile. Gallbladder specimens were collected from 24 patients who underwent elective laparoscopic cholecystectomy for symptomatic gallstone disease. The control group consisted of 25 consecutive patients who received elective treatment for pancreatic head tumours. Telocytes were visualized in paraffin sections of gallbladders with double immunofluorescence using primary antibodies against c‐Kit (anti‐CD117) and anti‐mast cell tryptase. Cholesterol, phospholipid and bile acid levels were measured in gallbladder bile. The number of telocytes in the gallbladder wall was significantly lower in the study group than that in the control group (3.03 ± 1.43 versus 6.34 ± 1.66 cell/field of view in the muscularis propria, P < 0.001) and correlated with a significant increase in the cholesterol saturation index. The glycocholic and taurocholic acid levels were significantly elevated in the control subjects compared with the study group. The results suggest that bile composition may play an important role in the reduction in telocytes density in the gallbladder.

Methods of Evidence-Based Anatomy: a guide to conducting systematic reviews and meta-analysis of anatomical studies.

Evidence-Based Anatomy (EBA) is the concept of applying evidence-based principles and research methods to the anatomical sciences. While narrative reviews are common in the anatomical sciences, true systematic reviews (SR) and meta-analysis (MA) are only beginning to grow in popularity. In order to enhance the quality of future EBA studies, and ensure the clinical reliability of their results, a uniform methodology is needed. In this paper, we present a step-by-step methodological guide for performing SRs and MAs of anatomical studies. We address the EBA-specific challenges in each step of the SR and MA process, and discuss methods and strategies to overcome these difficulties. Furthermore, we discuss in detail the statistical methods used in MA of anatomical data, including multi-categorical and single-categorical pooled prevalence estimates, as well as pooled means of one group. Lastly, we discuss the major limitations of EBA, including the lack of a proper quality assessment tool for anatomical studies. The methods described in this paper present a uniform road map for future EBA studies.

Development of the Anatomical Quality Assurance (AQUA) checklist: Guidelines for reporting original anatomical studies

The rise of evidence‐based anatomy has emphasized the need for original anatomical studies with high clarity, transparency, and comprehensiveness in reporting. Currently, inconsistencies in the quality and reporting of such studies have placed limits on accurate reliability and impact assessment. Our aim was to develop a checklist of reporting items that should be addressed by authors of original anatomical studies. The study steering committee formulated a preliminary conceptual design and began to generate items on the basis of a literature review and expert opinion. This led to the development of a preliminary checklist. The validity of this checklist was assessed by a Delphi procedure, and feedback from the Delphi panelists, who were experts in the area of anatomical research, was used to improve it. The Delphi procedure involved 12 experts in anatomical research. It comprised two rounds, after which unanimous consensus was reached regarding the items to be included in the checklist. The steering committee agreed to name the checklist AQUA. The preliminary AQUA Checklist consisted of 26 items divided into eight sections. Following round 1, some of the items underwent major revision and three new ones were introduced. The checklist was revised only for minor language inaccuracies after round 2. The final version of the AQUA Checklist consisted of the initial eight sections with a total of 29 items. The steering committee hopes the AQUA Checklist will improve the quality and reporting of anatomical studies. Clin. Anat. 30:14–20, 2017.

Development of the anatomical quality assessment (AQUA) tool for the quality assessment of anatomical studies included in meta‐analyses and systematic reviews

Critical appraisal of anatomical studies is essential before the evidence from them undergoes meta‐epidemiological synthesis. However, no instrument for appraising anatomical studies with inherent applicability to different study designs is available. We aim to develop a generic yet comprehensive tool for assessing the quality of anatomical studies using a formal consensus method. The study steering committee formulated an initial conceptual design and generated items for a preliminary tool on the basis of a literature review and expert opinion. A Delphi procedure was then adopted to assess the validity of the preliminary tool. Feedback from the Delphi panelists was used to improve it. The Delphi procedure involved 12 experts in anatomical research. It comprised two rounds, after which unanimous consensus was reached about the items to be included. The preliminary tool consisted of 20 items, which were phrased as signaling questions and organized into five domains: 1. Aim and subject characteristics, 2. Study design, 3. Characterization of methods, 4. Descriptive anatomy, and 5. Results reporting. Each domain was set to end with a risk of bias question. Following round 1, some of the items underwent major revision, although agreement was reached regarding inclusion of all the domains and signaling questions in the preliminary tool. The tool was revised only for minor language inaccuracies after round 2. The AQUA Tool was designed to assess the quality and reliability of anatomical studies. It is currently undergoing a validation process. Clin. Anat. 30:6–13, 2017.

The Prevalence of Anatomical Variations of the Median Nerve in the Carpal Tunnel: A Systematic Review and Meta-Analysis

Background and Objective The course and branches of the median nerve (MN) in the wrist vary widely among the population. Due to significant differences in the reported prevalence of such variations, extensive knowledge on the anatomy of the MN is essential to avoid iatrogenic nerve injury. Our aim was to determine the prevalence rates of anatomical variations of the MN in the carpal tunnel and the most common course patterns and variations in its thenar motor branch (TMB). Study Design A systematic search of all major databases was performed to identify articles that studied the prevalence of MN variations in the carpal tunnel and the TMB. No date or language restrictions were set. Extracted data was classified according to Lanzs classification system: variations in the course of the single TMB—extraligamentous, subligamentous, and transligamentous (type 1); accessory branches of the MN at the distal carpal tunnel (type 2); high division of the MN (type 3); and the MN and its accessory branches proximal to the carpal tunnel (type 4). Pooled prevalence rates were calculated using MetaXL 2.0. Results Thirty-one studies (n = 3918 hands) were included in the meta-analysis. The pooled prevalence rates of the extraligamentous, subligamentous, and transligamentous courses were 75.2% (95%CI:55.4%-84.7%), 13.5% (95%CI:3.6%-25.7%), and 11.3% (95%CI:2.4%-23.0%), respectively. The prevalence of Lanz group 2, 3, and 4 were 4.6% (95%CI:1.6%-9.1%), 2.6% (95%CI:0.1%-2.8%), and 2.3% (95%CI:0.3%-5.6%), respectively. Ulnar side of branching of the TMB was found in 2.1% (95%CI:0.9%-3.6%) of hands. The prevalence of hypertrophic thenar muscles over the transverse carpal ligament was 18.2% (95%CI:6.8%-33.0%). A transligamentous course of the TMB was more commonly found in hands with hypertrophic thenar muscles (23.4%, 95%CI:5.0%-43.4%) compared to those without hypertrophic musculature (1.7%, 95%CI:0%-100%). In four studies (n = 423 hands), identical bilateral course of the TMB was found in 72.3% (95%CI:58.4%-84.4%) of patients. Conclusions Anatomical variations in the course of the TMB and the MN in the carpal tunnel are common in the population. Thus, we recommend an ulnar side approach to carpal tunnel release, with a careful layer by layer dissection, to avoid iatrogenic damage to the TMB.

The role of serum procalcitonin in the diagnosis of bacterial meningitis in adults: a systematic review and meta-analysis

OBJECTIVE Clinically, it is often difficult to differentiate between bacterial and viral aetiologies in adults with suspected meningitis. Several studies have demonstrated the potential use of serum procalcitonin (PCT) in making this differentiation. The aim was to pool these studies into a meta-analysis to determine the diagnostic accuracy of PCT. METHODS Major electronic databases were searched for articles studying the use of serum PCT in the differentiation of bacterial and viral meningitis in adult patients. No date or language restrictions were applied. Data analysis was performed using Meta-DiSc 1.4 and MIX 2.0. RESULTS Nine studies (n=725 patients) were included in the meta-analysis. Serum PCT was found to be a highly accurate test for diagnosing meningitis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio (DOR) for PCT were 0.90 (95% confidence interval (CI) 0.84-0.94), 0.98 (95% CI 0.97-0.99), 27.3 (95% CI 8.2-91.1), 0.13 (95% CI 0.07-0.26), and 287.0 (95% CI 58.5-1409.0), respectively. PCT was found to be far superior to C-reactive protein, which had a pooled DOR of only 22.1 (95% CI 12.7-38.3). CONCLUSIONS Serum PCT is a highly accurate diagnostic test that can be used by physicians for rapid differentiation between bacterial and viral causes of meningitis in adults.

Loss of gallbladder interstitial Cajal-like cells in patients with cholelithiasis

Background  Interstitial cells of Cajal (ICCs) play an important role in the regulation of gut motility. There is growing evidence that interstitial Cajal‐like cells (ICLCs) are present in the gallbladder wall. We hypothesize that changes in the density of ICLCs in the gallbladder wall may lead to the development of cholelithiasis due to the impairment of the gallbladder motility. The purpose of this study was to identify ICLCs in the gallbladders of patients with gallstones and to assess their densities.

Absence of the musculocutaneous nerve associated with a supernumerary head of biceps brachii: a case report

Unusual neural and muscular variations in the right upper limb were noted during anatomical dissection of a 54-year-old male cadaver. The absence of the musculocutaneous nerve was correlated with a three-headed biceps brachii muscle. The distribution of muscular branches innervating the anterior compartment of the muscles of the arm was different to the cases described in literature hitherto. This report contains a comparison of various instances where the musculocutaneous nerve is absent. We discuss the embryological explanation for this anomaly and its clinical results. It is important to be aware of such possible anatomical variations during clinical practice.

Median and Ulnar Nerve Anastomoses in the Upper Limb: A Meta-Analysis.

The most frequently described anomalous neural connections between the median and ulnar nerves in the upper limb are: Martin‐Gruber anastomosis (MGA), Marinacci anastomosis (MA), Riche‐Cannieu anastomosis (RCA), and Berrettini anastomosis (BA). The reported prevalence rates and characteristics of these anastomoses vary significantly between studies.

Evidence of interstitial Cajal-like cells in human gallbladder.

The aim of this study was to assess the presence of interstitial Cajal-like cells (ICLCs) in the human gallbladder and to determine their distinctive characteristics on the basis of double immunohistochemical stain- ing. Gallbladder specimens were obtained from 30 patients subjected to elective laparoscopic cholecystectomy for symptomatic gallstone disease. Tissue samples were fixed in 4% phosphate-buffered paraformaldehyde, processed, embedded in paraffin, and, after sectioning, routinely stained with HE. Tissue antigens were re- trieved using the heat-induced epitope retrieval (HIER) method. For simultaneous visualisation of two anti- gens, an indirect double immunofluorescence procedure was applied. ICLCs were defined as CD117-immunop- ositive and tryptase-immunonegative objects. They were predominantly fusiform in shape with sparse branches that were visible in some sections. ICLCs were observed throughout the organ including the gallbladders fun- dus, body (corpus) and neck, being most numerous in the corpus. The ICLCs were detected almost exclusively within the muscularis propria and they were arranged parallel to smooth muscle cells. The following subpopula- tions of ICLCs were observed: ICLC-IM (intramuscular ICLCs) localised between smooth muscle fibres form- ing one muscle bundle; and ICLC-IB (interbundle ICLCs) localised within the connective tissue separating smooth muscle bundles. Thus, the presence of ICLCs in the human gallbladder was clearly identified, demon- strated by double immunohistochemistry which was found to be a reliable method for differentiating ICLCs from mast cells. (Folia Histochemica et Cytobiologica 2012, Vol. 50, No. 4, 581-585)