Osteoarthritis Development Following Meniscectomy vs. Meniscal Repair for Posterior Medial Meniscus Injuries: A Systematic Review.

This systematic review aims to evaluate critically and synthesize the existing literature on the outcomes of meniscectomy versus meniscal repair for posterior medial meniscus injuries, with a focus on osteoarthritis (OA) development. We sought to assess the incidence of OA following both treatment modalities, compare functional outcomes post-treatment, and identify factors influencing treatment choice, providing evidence-based recommendations for clinical decision-making. A comprehensive search strategy was employed across PubMed, Scopus, and Embase up until December 2023, adhering to PRISMA guidelines. The primary outcomes included OA development, functional knee outcomes, and quality of life measures. Six studies met the inclusion criteria, encompassing 298 patients. The systematic review revealed a significant association between meniscal repair and decreased progression of OA compared to meniscectomy. Meniscectomy patients demonstrated a 51.42% progression rate towards OA, significantly higher than the 21.28% observed in meniscal repair patients. Functional outcomes, as measured by the International Knee Documentation Committee (IKDC) and Lysholm scores, were notably better in the repair group, with average scores of 74.68 (IKDC) and 83.78 (Lysholm) compared to 67.55 (IKDC) and 74.56 (Lysholm) in the meniscectomy group. Furthermore, the rate of complete healing in the repair group was reported at 71.4%, as one study reported, indicating a favorable prognosis for meniscal preservation. However, these pooled data should be interpreted with consideration to the heterogeneity of the analyzed studies. Meniscal repair for posterior medial meniscus injuries is superior to meniscectomy in preventing OA development and achieving better functional outcomes and quality of life post-treatment. These findings strongly suggest the adoption of meniscal repair as the preferred treatment modality for such injuries, emphasizing the need for a paradigm shift in clinical practice towards preserving meniscal integrity to optimize patient outcomes.

Angiosome-Targeted Infrapopliteal Angioplasty: Impact on Clinical Outcomes-An Observational Study.

Background: Revascularization based on the angiosome concept (AC) is a controversial subject because there is currently no clear evidence of its efficacy, due to the heterogeneity of patients (multiple and diverse risk factors and comorbidities, multiple variations in the affected angiosomes). Choke vessels change the paradigm of the AC, and the presence or absence of the plantar arch directly affects the course of targeted revascularization. The aim of this study was to evaluate the effect of revascularization based on the AC in diabetic patients with chronic limb-threatening ischemia (CLTI). Methods: This retrospective analysis included 51 patients (40 men, 11 women), with a mean age of 69 years (66-72) and a total of 51 limbs, who presented with Rutherford 5-6 CLTI, before and after having undergone a drug-coated balloon angioplasty (8 patients) or plain balloon angioplasty (43). Between November 2018 and November 2019, all patients underwent below-the-knee balloon angioplasties and were followed up for an average of 12 months. The alteration of microcirculation was compared between directly and indirectly revascularized angiosomes. The study assessed clinical findings and patient outcomes, with follow-up investigations, comparing wound healing rates between the different revascularization methods. Patient records and periprocedural leg digital subtraction angiographies (DSA) were analyzed. Differences in outcomes after direct revascularization and indirect percutaneous transluminal angioplasty (PTa) were examined using Cox proportional hazards analysis, with the following endpoints: ulcer healing, limb salvage, and also amputation-free survival. Results: Direct blood flow to the angiosome supplying the ulcer area was achieved in 38 legs, in contrast to 13 legs with indirect revascularization. Among the cases, there were 39 lesions in the anterior tibial artery (ATA), 42 lesions in the posterior tibial artery (PTA), and 8 lesions in the peroneal artery (PA). According to a Cox proportional hazards analysis, having fewer than three (<3) affected angiosomes (HR 0.49, 95% CI 0.19-1.25, p = 0.136) was associated with improved wound healing. Conversely, wound healing outcomes were least favorable after indirect angioplasty (p = 0.206). When adjusting the Cox proportional hazard analysis for the number of affected angiosomes, it was found that direct drug-coated angioplasty resulted in the most favorable wound healing (p = 0.091). At the 1-year follow-up, the major amputation rate was 17.7%, and, according to a Cox proportional hazards analysis, atrial fibrillation (HR 0.85, 95% CI 0.42-1.69, p = 0.637), hemodialysis (HR 1.26, 95% CI 0.39-4.04, p = 0.699), and number of affected angiosomes > 3 (HR 0.94, 95% CI 0.63-1.39, p = 0.748) were significantly associated with poor leg salvage. Additionally, direct endovascular revascularization was associated with a lower rate of major amputation compared to indirect angioplasty (HR 1.09, 95% CI 0.34-3.50, p = 0.884). Conclusions: Observing the angiosomes concept in decision-making appears to result in improved rates of arterial ulcer healing and leg salvage, particularly in targeted drug-coated balloon angioplasty for diabetic critical limb ischemia, where multiple angiosomes are typically affected.

Diagnostic criteria for Buerger's disease: International Consensus of VAS - European Independent Foundation in Angiology/Vascular Medicine.

Buerger's disease (BD) remains a debilitating condition and early diagnosis is paramount for its effective management. Despite many published diagnostic criteria for BD, selective criteria have been utilized in different vascular centers to manage patients with BD worldwide. A recent international Delphi Consensus Study on the diagnostic criteria of BD showed that none of these published diagnostic criteria have been universally accepted as a gold standard. Apart from the presence of smoking, these published diagnostic criteria have distinct differences between them, rendering the direct comparison of patient outcomes difficult. Hence, the expert committees from the Working Group of the VAS-European Independent Foundation in Angiology/Vascular Medicine critically reviewed the findings from the Delphi study and provided practical recommendations on the diagnostic criteria for BD, facilitating its universal use. We recommend that the 'definitive' diagnosis of BD must require the presence of three features (history of smoking, typical angiographic features and typical histopathological features) and the use of a combination of major and minor criteria for the 'suspected' diagnosis of BD. The major criterion is the history of active tobacco smoking. The five minor criteria are disease onset at age less than 45 years, ischemic involvement of the lower limbs, ischemic involvement of one or both of the upper limbs, thrombophlebitis migrans and red-blue shade of purple discoloration on edematous toes or fingers. We recommend that a 'suspected' diagnosis of BD is confirmed in the presence of a major criterion plus four or more minor criteria. In the absence of the major criterion or in cases of fewer than four minor criteria, imaging and laboratory data could facilitate the diagnosis. Validation studies on the use of these major and minor criteria are underway.

Patients' Buying Behavior for Non-Reimbursed Off-Loading Devices Used in Diabetic Foot Ulcer Treatment-An Observational Study during COVID-19 Pandemic from a Romanian Physical Therapy Unit.

Diabetic foot ulcer non-reimbursed treatment depends on multiple factors, including the patient's buying behaviors. Factors affecting buying behaviors for the removable off-loading devices are not completely understood. The aim of this study was to investigate the patients' buying behaviors of the removable off-loading devices and their influence on the DFU treatment outcomes remotely monitored during the COVID-19 pandemic. In this prospective observational study, 45 patients affected by diabetic peripheral neuropathy, with/without peripheral arterial disease, with foot ulcers treated with removable devices were remotely monitored. Prefabricated removable cast walkers, insoles, and therapeutic footwear were the proposed off-loading methods. Patients affected by high blood pressure (p = 0.018), peripheral arterial disease (p = 0.029), past amputations (p = 0.018), and ulcer on the left foot (p = 0.007) bought removable cast walkers. Rural provenience (p = 0.011) and male (p = 0.034) did not buy a removable walker. The healing rate was 69.4%, while the median healing time was 20 weeks. High blood pressure negatively influenced healing time (p = 0.020). Patients who bought the most efficient treatment method for DFUs were females from urban provenience, with amputation in the past, with peripheral arterial disease, and with high blood pressure.

Lower Extremity Amputation and Peripheral Revascularisation Rates in Romania and Their Relationship with Comorbidities and Vascular Care.

(1) Background: This retrospective Romanian study aimed to calculate the rate of, and comparison between, amputation and revascularisation for patients with either cardiovascular or diabetic comorbidities. (2) Materials: In our hospital-based database, we analysed patient-level data from a series of 61 hospitals for 2019, which covers 44.9% of the amputation patients for that year. The national database is compiled by the national houses of insurance and was used to follow amputations and revascularisations between 2016 and 2021. (3) Results: During the six-year period, the mean number of amputations and revascularisations was 72.4 per 100,000 inhabitants per year for both groups. In this period, a decline in open-surgical revascularisation was observed from 58.3% to 47.5% in all interventions but was not statistically significant (r = -0.20, p = 0.70). The mean age of patients with amputation (hospital-based database) was 67 years. Of these patients, only 5.1% underwent revascularisation in the same hospital prior to amputation. The most common comorbidities in those undergoing amputations were peripheral arterial disease (76.8%), diabetes (60.8%), and arterial hypertension (53.5%). Most amputations were undertaken by general surgeons (73.0%) and only a small number of patients were treated by vascular surgeons (17.4%). (4) Conclusions: The signal from our data indicates that Romanian patients probably have a high risk of amputation > 5 years earlier than Western European countries, such as Denmark, Finland, and Germany. The prevalence of revascularisations in Romania is 64% lower than in the Western European countries.

A Signal Processing Method for Assessing Ankle Torque with a Custom-Made Electronic Dynamometer in Participants Affected by Diabetic Peripheral Neuropathy.

Portable, custom-made electronic dynamometry for the foot and ankle is a promising assessment method that enables foot and ankle muscle function to be established in healthy participants and those affected by chronic conditions. Diabetic peripheral neuropathy (DPN) can alter foot and ankle muscle function. This study assessed ankle toque in participants with diabetic peripheral neuropathy and healthy participants, with the aim of developing an algorithm for optimizing the precision of data processing and interpretation of the results and to define a reference frame for ankle torque measurement in both healthy participants and those affected by DPN. This paper discloses the software chain and the signal processing methods used for voltage-torque conversion, filtering, offset detection and the muscle effort type identification, which further allowed for a primary statistical report. The full description of the signal processing methods will make our research reproducible. The applied algorithm for signal processing is proposed as a reference frame for ankle torque assessment when using a custom-made electronic dynamometer. While evaluating multiple measurements, our algorithm permits for a more detailed parametrization of the ankle torque results in healthy participants and those affected by DPN.

Acute Effects of Sedentary Behavior on Ankle Torque Assessed with a Custom-Made Electronic Dynamometer.

Inactivity negatively influences general health, and sedentary behaviour is known to impact the musculoskeletal system. The aim of the study was to assess the impact of time spent in active and sedentary behaviour on foot muscle strength. In this observational study, we compared the acute effects of one day of prolonged sitting and one day of low-to-moderate level of activity on ankle torque in one group of eight healthy participants. Peak ankle torque was measured using a portable custom-made electronic dynamometer. Three consecutive maximal voluntary isometric contractions for bilateral plantar flexor and dorsiflexor muscles were captured at different moments in time. The average peak torque significant statistically decreased at 6 h (p = 0.019) in both static and active behaviours, with a higher average peak torque in the active behaviour (p < 0.001). Age, gender, body mass index and average steps did not have any significant influence on the average value of maximal voluntary isometric contraction. The more time participants maintained either static or active behaviour, the less force was observed during ankle torque testation. The static behaviour represented by the sitting position was associated with a higher reduction in the average peak ankle torque during a maximal voluntary isometric contraction when compared to the active behaviour.

An International Delphi Consensus on Diagnostic Criteria for Buerger's Disease.

BACKGROUND: Buerger's disease (BD) remains a debilitating condition. Despite multiple published diagnostic criteria for BD, none is universally accepted as a gold standard. METHODS: We conducted a 2-round modified Delphi consensus study to establish a consensus on the diagnostic. The questionnaire included statements from several commonly used diagnostic criteria for BD. Qualitative and quantitative analysis methods were performed. An agreement level of 70% was applied. RESULTS: Twenty nine experts from 18 countries participated in this study. Overall, 75 statements were circulated in Round 1. Of these, 28% of statements were accepted. Following comments, 21 statements were recirculated in Round 2 and 90% were accepted. Although more than 90% of the experts did not agree that the diagnosis of BD can be based only on clinical manifestation, none of the nonclinical manifestations of BD were agreed as a part of the diagnostic criteria. There was an agreement that a history of tobacco consumption in any form, not necessarily confined to the current use, should be a part of the diagnostic criteria of BD. The history of thrombophlebitis migrans, even if not present at presentation, was accepted as a clue for BD diagnosis. It was also agreed that discoloration of the toes or fingers could be included in the diagnostic criteria of BD. Experts agreed that histology results could differentiate BD from atherosclerosis obliterans and other types of vasculitis. The presence of corkscrew collaterals on imaging and burning pain reached the agreement at the first round but not at the second. There was no consensus regarding age cut-off, the requirement of normal lipid profile, and normal blood glucose for BD diagnosis. CONCLUSIONS: The present study demonstrated discrepancies in the various published diagnostic criteria for BD and their selective utilization in routine clinical practice worldwide. We propose that all published diagnostic criteria for BD be re-evaluated for harmonization and universal use.

Experimental swine models for perforator flap dissection in reconstructive microsurgery.

BACKGROUND: Perforator flaps account for a fraction of reconstructive procedures despite their growing popularity. Specific microsurgical skills are required for successful harvesting of perforator flaps, which are difficult to attain through direct operating room training. Cadaver and small animal dissection cannot simulate human perforator dissection, lacking either bleeding and vessel feedback or providing too small calibers. Thus, we have developed and refined over the last ten years five perforator flaps models in living pig, described their harvesting technique and provided evidence for their effectiveness as perforator flap training models. METHOD: CT angiography data from ten living pigs was used for detailed examination of the integument's vascular anatomy. Microsurgical techniques were used to standardize and harvest the perforator flaps in acute models. The same operator-assistant team, with no prior perforator flap harvesting experience, raised all flaps in a sequential manner, one animal per day, during a 7 weeks timespan. Porcine flaps were compared to human counterparts in terms of vessel caliber, dissection times. Immediate flap survival was measured as duration of perforator pulsation after completion of flap harvesting, measured every 10 minutes for up to two hours. RESULTS: Five perforator flaps were standardized, based on the deep cranial epigastric, thoracodorsal, lateral intercostal, cranial gluteal and dorsal cervical arteries and the operative technique was described in detail. Mean pig perforator size was 1.24±0.36 mm and mean pedicle diameter was 2.78±0.8 mm, which matched closely the human calibers for each flap. Total harvesting time increased 22.4% between the first two experiments due to a more cautious approach following the lack of perforator pulsation in all flaps in the first experimental animal. A total decrease of 44.4% harvesting time between second and last experiment was observed, as expected with all repetitive surgical procedures. Post-operative perforator pulsation time revealed a steep learning curve, with no or short-term pulsatile perforators in the first five pigs, followed by a 275% increase in total perforator pulsation time between 5th and 6th experimental animal. Based on these findings we provide a description of the most common mistakes, their consequences and gestures which can be trained using the pig perforator flaps, in order to overcome these mistakes. CONCLUSION: These five pig perforator flap models provide a fast and efficient learning tool to develop perforator flap harvesting skills safely. Surgical training using these five experimental models offers a similar hands-on perforator flap dissection experience as with human tissue, based on the similar sized calibers of both perforators and pedicles with their human counterparts.

A Custom-Made Electronic Dynamometer for Evaluation of Peak Ankle Torque after COVID-19.

The negative effects of SARS-CoV-2 infection on the musculoskeletal system include symptoms of fatigue and sarcopenia. The aim of this study is to assess the impact of COVID-19 on foot muscle strength and evaluate the reproducibility of peak ankle torque measurements in time by using a custom-made electronic dynamometer. In this observational cohort study, we compare two groups of four participants, one exposed to COVID-19 throughout measurements and one unexposed. Peak ankle torque was measured using a portable custom-made electronic dynamometer. Ankle plantar flexor and dorsiflexor muscle strength was captured for both feet at different ankle angles prior and post COVID-19. Average peak torque demonstrated no significant statistical differences between initial and final moment for both groups (p = 0.945). An increase of 4.8%, p = 0.746 was obtained in the group with COVID-19 and a decrease of 1.3%, p = 0.953 was obtained in the group without COVID-19. Multivariate analysis demonstrated no significant differences between the two groups (p = 0.797). There was a very good test−retest reproducibility between the measurements in initial and final moments (ICC = 0.78, p < 0.001). In conclusion, peak torque variability is similar in both COVID-19 and non-COVID-19 groups and the custom-made electronic dynamometer is a reproducible method for repetitive ankle peak torque measurements.

Dataset of the vascular e-Learning during the COVID-19 pandemic (EL-COVID) survey.

This dataset supports the findings of the vascular e-Learning during the COVID-19 pandemic survey (the EL-COVID survey). The General Data Protection Regulation (GDPR) of the European Union was taken into consideration in all steps of data handling. The survey was approved by the institutional ethics committee of the Primary Investigator and an online English survey consisting of 18 questions was developed ad-hoc. A bilingual English-Mandarin version of the questionnaire was developed according to the instructions of the Chinese Medical Association in order to be used in mainland People's Republic of China. Differences between the two questionnaires were minor and did affect the process of data collection. Both questionnaires were hosted online. The EL-COVID survey was advertised through major social media. All national and regional contributors contacted their respective colleagues through direct messaging on social media or by email. Eight national societies or groups supported the dissemination of the EL-COVID survey. The data provided demographics information of the EL-COVID participants and an insight on the level of difficulty in accessing or citing previously attended online activities and whether participants were keen on citing these activities in their Curricula Vitae. A categorization of additional comments made by the participants are also based on the data. The survey responses were filtered, anonymized and submitted to descriptive analysis of percentage.

Vascular e-Learning During the COVID-19 Pandemic: The EL-COVID Survey.

BACKGROUND: The corona virus disease (COVID-19) pandemic has radically changed the possibilities for vascular surgeons and trainees to exchange knowledge and experience. The aim of the present survey is to inventorize the e-learning needs of vascular surgeons and trainees as well as the strengths and weaknesses of vascular e-Learning. METHODS: An online survey consisting of 18 questions was created in English, with a separate bilingual English-Mandarin version. The survey was dispersed to vascular surgeons and trainees worldwide through social media and via direct messaging from June 15, 2020 to October 15, 2020. RESULTS: Eight hundred and fifty-six records from 84 different countries could be included. Most participants attended several online activities (>4: n = 461, 54%; 2-4: n = 300, 35%; 1: n = 95, 11%) and evaluated online activities as positive or very positive (84.7%). In deciding upon participation, the topic of the activity was most important (n = 440, 51.4%), followed by the reputation of the presenter or the panel (n = 178, 20.8%), but not necessarily receiving accreditation or certification (n = 52, 6.1%). The survey identified several shortcomings in vascular e-Learning during the pandemic: limited possibility to attend due to lack of time and increased workload (n = 432, 50.5%), no protected/allocated time (n = 488, 57%) and no accreditation or certification, while technical shortcomings were only a minor problem (n = 25, 2.9%). CONCLUSIONS: During the COVID-19 pandemic vascular e-Learning has been used frequently and was appreciated by vascular professionals from around the globe. The survey identified strengths and weaknesses in current e-Learning that can be used to further improve online learning in vascular surgery.

Milestones in thromboangiitis obliterans: a position paper of the VAS-European independent foundation in angiology/vascular medicine.

Even today thromboangiitis obliterans has disease features that remain misunderstood or underappreciated. The epidemiology, etiology and pathophysiology of the disease are still unclear. Biomarkers and disease activity markers are lacking, thus clinical assessment is difficult. We are still struggling to establish unique diagnostic, staging and treatment criteria. This is an academic-collaborative effort to describe the pathophysiology, the clinical manifestations, the diagnostic approach, and the challenges of management of patients with TAO. A systematic search for relevant studies dating from 1900 to the end of 2020 was performed on the PubMed, SCOPUS, and Science Direct databases. Given the intriguing nature of presentation of TAO, its management, to some extent is not only different in different regions of the world but also varies within the same region. Following this project, we discovered ambiguity, overlap and lack of clear-cut criteria for management of TAO. An international group of experts however came to one conclusion. They all agree that management of TAO needs a call for action for a renewed global look with multi-center studies, to update the geographical distribution of the disease and to establish a unique set of diagnostic criteria and a consensus-based guideline for best treatment based on current evidence.

A Custom-Made Lower Limb Dynamometer for Assessing Ankle Joint Torque in Humans: Calibration and Measurement Procedures.

Custom-made dynamometry was shown to objectively analyze human muscle strength around the ankle joint with accuracy, easy portability and low costs. This paper describes the full method of calibration and measurement setup and the measurement procedure when capturing ankle torque for establishing reliability of a portable custom-built electronic dynamometer. After considering the load cell offset voltage, the pivotal position was determined, and calibration with loads followed. Linear regression was used for calculating the proportionality constant between torque and measured voltage. Digital means were used for data collection and processing. Four healthy consenting participants were enrolled in the study. Three consecutive maximum voluntary isometric contractions of five seconds each were registered for both feet during plantar flexion/dorsiflexion, and ankle torque was then calculated for three ankle inclinations. A calibration procedure resulted, comprising determination of the pivotal axis and pedal constant. Using the obtained data, a measurement procedure was proposed. Obtained contraction time graphs led to easier filtering of the results. When calculating the interclass correlation, the portable apparatus demonstrated to be reliable when measuring ankle torque. When a custom-made dynamometer was used for capturing ankle torque, accuracy of the method was assured by a rigorous calibration and measurement protocol elaboration.

Role of Reconstructive Microsurgery in Tubal Infertility in Young Women.

AIM: Here, we retrospectively analyzed the success rate of reconstructive microsurgery for tubal infertility (RMTI) as a "first-line" approach to achieving tubal reversal and pregnancy after tubal infertility. PATIENTS AND METHODS: During 9 consecutive years (2005-2014), 96 patients diagnosed with obstructive tubal infertility underwent RMTI (tubal reversal, salpingostomy, and/or tubal implantation) in our centre. The outcomes are presented in terms of tubal reversal rate and pregnancy and correlated with age, level of tubal obstruction, and duration of tubal infertility. RESULTS: The overall tubal reversal rate was 87.56% (84 patients). The 48-month cumulative pregnancy rate was 78.04% (64 patients), of which seven ectopic pregnancies occurred (8.53%). The reversibility rate for women under 35 yo was 90.47%, with a birth rate of 73.01%. The reconstruction at the infundibular segments favored higher ectopic pregnancy rates (four ectopic pregnancies for anastomosis at infundibular level-57.14%, two for ampullary level-28.57%, and one for replantation technique-14.28%), with a significant value for p < 0.05. CONCLUSIONS: In the context of IVF "industrialization", reconstructive microsurgery for tubal infertility has become increasingly less favored. However, under available expertise and proper indication, RMTI can be successfully used to restore a woman's ability to conceive naturally with a high postoperative pregnancy rate overall, especially in women under 35 yo.

A sequence of flaps and dissection exercises in the living model to improve the learning curve for perforator flap surgery.

INTRODUCTION: The training to learn how to perform perforator flaps requires practice on a living model to optimize dissection and to evaluate outcome. The purpose of this study was to describe a training model that optimizes the use of animals in order to perform the maximum number of exercises per animal. MATERIAL AND METHODS: The sequence has been planned and practiced by the first and last author, recorded perfected and implemented in a two-day surgical course. The sequence was then evaluated by the trainers and the trainees by means of a questionnaire. RESULTS: All students were able to complete the sequence of exercises before the end of the second day except two (8/10) who could not complete one exercise each. The students considered the Deep Superior Epigastric Artery Perforator flap the most difficult to perform, being the most technically demanding. The sequence of exercises was judged either easily reproducible or reproducible by all the students. Two students suggested to postpone the DSEAP flap to the second day, after some training, to optimize the experience with the most challenging and rewarding flap. CONCLUSIONS: The training sequence proposed offers a wide range of exercises and allows four trainees, divided in two teams, to work and learn on the same animal. They can perform a wide range of flaps and also harvest the internal mammary vessels. The living model allows for evaluation of the quality of the surgical performance, judged by the difficulties and complications encountered during dissection, and finally through the feedback of flap perfusion.

Chronic Hindlimb Ischemia Assessment; Quantitative Evaluation Using Laser Doppler in a Rodent Model of Surgically Induced Peripheral Arterial Occlusion.

Therapeutic neoangiogenesis (TNA) holds promise as a treatment for peripheral arterial disease. Nevertheless, proper tools for in vivo pre-clinical investigation of different TNA approaches and their effects are still lacking. Here we describe a chronic ischemic hindlimb model in rats using laser Doppler quantitative evaluation of tissue perfusion. Male Wistar rats (n = 20), aged between 6-8 months, with an average weight of 287 ± 26.74 g, were used. Animals were divided into two experimental groups: group A (n = 17; hindlimb chronic ischemia model) and group B (n = 3; control). Hindlimb ischemia was induced by concomitant ligation of the right femoral and popliteal artery. Evaluation of tissue perfusion was quantified in perfusion units (PU) on a scale from 0 to 500 (500 PU = maximal detectable perfusion) by laser Doppler analysis at day 0, day 15 and day 30 after induction of ischemia. Induction of chronic ischemia in the rat hindlimb by concomitant ligation of the femoral and popliteal artery can be readily obtained but requires basic microsurgical skills. Laser Doppler analysis has shown unaltered ischemia levels throughout the study (129,17 PU ± 3.13 day 0 vs. 130,33 PU day 30 ± 3,27, p = not significant (n.s.)). We demonstrate a simple and reproducible model of chronic hindlimb ischemia in rats, with stable tissue perfusion levels that are accurately quantified using laser Doppler technology. Hence, this model can represent a valid tool for further studies involving therapeutic neoangiogenesis.

Intestinal Preservation Injury: A Comparison Between Rat, Porcine and Human Intestines.

Advanced preservation injury (PI) after intestinal transplantation has deleterious short- and long-term effects and constitutes a major research topic. Logistics and costs favor rodent studies, whereas clinical translation mandates studies in larger animals or using human material. Despite diverging reports, no direct comparison between the development of intestinal PI in rats, pigs, and humans is available. We compared the development of PI in rat, porcine, and human intestines. Intestinal procurement and cold storage (CS) using histidine-tryptophan-ketoglutarate solution was performed in rats, pigs, and humans. Tissue samples were obtained after 8, 14, and 24 h of CS), and PI was assessed morphologically and at the molecular level (cleaved caspase-3, zonula occludens, claudin-3 and 4, tricellulin, occludin, cytokeratin-8) using immunohistochemistry and Western blot. Intestinal PI developed slower in pigs compared to rats and humans. Tissue injury and apoptosis were significantly higher in rats. Tight junction proteins showed quantitative and qualitative changes differing between species. Significant interspecies differences exist between rats, pigs, and humans regarding intestinal PI progression at tissue and molecular levels. These differences should be taken into account both with regards to study design and the interpretation of findings when relating them to the clinical setting.