Hyperspectral Imaging (HSI) as a new diagnostic tool in free flap monitoring for soft tissue reconstruction: a proof of concept study.

OBJECTIVES: Free flap surgery is an essential procedure in soft tissue reconstruction. Complications due to vascular compromise often require revision surgery or flap removal. We present hyperspectral imaging (HSI) as a new tool in flap monitoring to improve sensitivity compared to established monitoring tools. METHODS: We performed a prospective observational cohort study including 22 patients. Flap perfusion was assessed by standard clinical parameters, Doppler ultrasound, and HSI on t0 (0 h), t1 (16-28 h postoperatively), and t2 (39-77 h postoperatively). HSI records light spectra from 500 to 1000 nm and provides information on tissue morphology, composition, and physiology. These parameters contain tissue oxygenation (StO2), near-infrared perfusion- (NIR PI), tissue hemoglobin- (THI), and tissue water index (TWI). RESULTS: Total flap loss was seen in n = 4 and partial loss in n = 2 cases. Every patient with StO2 or NIR PI below 40 at t1 had to be revised. No single patient with StO2 or NIR PI above 40 at t1 had to be revised. Significant differences between feasable (StO2 = 49; NIR PI = 45; THI = 16; TWI = 56) and flaps with revision surgery [StO2 = 28 (p < 0.001); NIR PI = 26 (p = 0.002); THI = 56 (p = 0.002); TWI = 47 (p = 0.045)] were present in all HSI parameters at t1 and even more significant at t2 (p < 0.0001). CONCLUSION: HSI provides valuable data in free flap monitoring. The technique seems to be superior to the gold standard of flap monitoring. StO2 and NIR PI deliver the most valuable data and 40 could be used as a future threshold in surgical decision making. Clinical Trial Register This study is registered at the German Clinical Trials Register (DRKS) under the registration number DRKS00020926.

Erratum to: Management of pelvic discontinuity in revision hip arthroplasty using a cementless acetabular cup with an iliac stem in combination with a cranial strap.

Erratum to: Orthopäde 2018 https://doi.org/10.1007/s00132-018-03675-5 Dear Reader,in the original online version of the article "Management of pelvic discontinuity in revision hip arthroplasty using a cementless acetabular cup with an iliac stem in combination with a cranial strap" in the section ….

Management of pelvic discontinuity in revision arthroplasty : Cementless acetabular cup with iliac stem and cranial strap.

BACKGROUND: Pelvic discontinuity causes severe destruction of the acetabular bony walls and is particularly difficult to manage. This article reports the short-term results and complications encountered in the management of loosening of the acetabular cup with pelvic discontinuity using an acetabular cup with an intramedullary iliac stem combined with an extramedullary iliac plate. MATERIAL AND METHODS: As part of this monocentric retrospective case analysis all patients who underwent acetabular revision surgery after THR due to loosening of the acetabular cup with pelvic discontinuity in this clinic from January 2016 to June 2017 were identified (n = 16). All patients underwent routine clinical and radiological follow-up. In addition, the Harris hip score (HHS) and the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) were evaluated as part of a 1-year follow-up. RESULTS: All patients were treated with an acetabular revision cup of appropriate size with intramedullary iliac stem combined with an anatomical extramedullary iliac plate. On clinical follow-up at 1 year (median follow-up time 14.5 ± 3.3 months), the average HHS was 69.3 ± 14.1 and the average WOMAC was 79.3 ± 11.7. Complications were registered in 7 out of the 16 patients whereby 1 showed aseptic loosening of the revision cup, dislocations were reported in 4 cases and infections in 2 cases. In the case of the two patients with infections a Girdlestone resection arthroplasty had to be performed. CONCLUSION: The overall complications and postoperative outcome in revision surgery after THR reported in the literature were compared to the results of this study. Compared to the results of salvage procedures using large or bipolar heads and Girdlestone resection arthroplasty, satisfactory results were obtained using the acetabular cup with an intramedullary iliac stem combined with an extramedullary iliac plate.

Two-stage posterior cross-labial transposition flap: a novel technique for labium minus reconstruction.

Distinctive asymmetry of the labia minora is an underestimated complication that can be congenital, post-traumatic, or occur after oncological intervention or aesthetic labioplasty. Affected women can be restricted functionally and in their sense of self-worth, aesthetic appearance and sexual life. In presenting this case of post-oncological labia minora asymmetry, we demonstrate our method of the two-stage posterior cross-labial transposition flap as a reliable technique for unilateral labium minus reconstruction.

[Cost comparison of conservative vs. surgical treatment of chronic lymphedema]. / Kostenvergleich der konservativen vs. operativen Therapie des chronischen Lymphödems.

BACKGROUND: Lymphedema is primarily treated conservatively using complex physical decongestion treatment (CDT). Lymphovenous anastomosis (LVA), vascularized lymph node transplantation (VLNT) and liposuction are available as surgical treatment methods; however, reimbursement in the diagnosis-related groups (DRG) system is sometimes inadequate or only possible following an individual application. The costs of these relatively new surgical procedures have not yet been set in relation to those of CDT. METHOD: The costs of conservative treatment were determined in accordance with the guidelines. The costs for LVA, VLNT and liposuction of the upper and lower extremities were estimated on the basis of the DRG reimbursement per case and the expected reduction in conservative measures according to current knowledge. The annual treatment costs were then compared. RESULTS: The annual treatment costs of LVA and VLNT are already lower than conservative treatment alone in the second postoperative year. Liposuction reaches this point in the 6th (upper extremity) or 47th postoperative year (lower extremity). CONCLUSION: The evidence for the positive effects of lymphatic surgery is still limited; however, it is recognizable that the curative surgical approach can significantly reduce the treatment costs and improve the quality of life of lymphedema patients; however, there is a lack of adequate reflection of the surgical effort in the reimbursement.

Hyperspectral Imaging Detects Clitoral Vascular Issues in Gender-Affirming Surgery.

The aim of this study was to assess the efficacy of hyperspectral imaging (HSI) as an intraoperative perfusion imaging modality during gender affirmation surgery (GAS). The hypothesis posited that HSI could quantify perfusion to the clitoral complex, thereby enabling the prediction of either uneventful wound healing or the occurrence of necrosis. In this non-randomised prospective clinical study, we enrolled 30 patients who underwent GAS in the form of vaginoplasty with the preparation of a clitoral complex from 2020 to 2024 and compared patients' characteristics as well as HSI data regarding clitoris necrosis. Individuals demonstrating uneventful wound healing pertaining to the clitoral complex were designated as Group A. Patients with complete necrosis of the neo-clitoris were assigned to Group B. Patient characteristics were collected and subsequently a comparative analysis carried out. No significant difference in patient characteristics was observed between the two groups. Necrosis occurred when both StO2 and NIR PI parameters fell below 40%. For the simultaneous occurrence of StO2 and NIR PI of 40% or less, a sensitivity of 92% and specificity of 72% was calculated. Intraoperatively, the onset of necrosis in the clitoral complex can be reliably predicted with the assistance of HSI.

Translation, Cross-Cultural Adaptation and Validation of the Lymphedema Quality of Life Questionnaire (LYMQOL) in German-Speaking Patients with Lymphedema of the Lower Limbs.

The LYMQOL Leg questionnaire is the most widely used, evidence-based tool for the assessment of health-related quality of life (HRQoL) in patients with lower limb lymphedema (LLL). It has been translated into several languages, but a German version is currently lacking. The aim of our study was to validate a German translation of LYMQOL Leg. Translation and cross-cultural adaptation were performed in accordance with ISPOR principles. A total of 103 patients with LLL from Germany, Austria, and Switzerland were interviewed twice. The content and face validity assessments indicated that the German LYMQOL Leg questionnaire was acceptable for interviewing patients with lymphedema. Comparing the LYMQOL Leg with the SF-36 demonstrated good construct validity. Reliability determined by the test-retest procedure was good (intra-class-correlation coefficients 0.68-0.92). Cronbach's alpha values ranged from 0.76 to 0.90 in both interviews, showing an acceptable internal consistency. The four domains of the questionnaire reached a cumulative variance of 52.7% in the factor analysis. The association between the lymphedema stages and the LYMQOL Leg domain scores was not significant. In conclusion, the validity of the German version of LYMQOL Leg, called LYMQOL Bein, was confirmed and thus represents a suitable tool for measuring HRQoL in German-speaking patients with LLL.

Translation, Cross-Cultural Adaptation and Validation of the Lymphedema Quality of Life Questionnaire (LYMQOL) in German-Speaking Patients with Upper Limb Lymphedema.

Objectives: The LYMQOL is the most frequently translated, validated, objective tool for assessing Health-Related Quality of Life (HRQoL) in individuals with upper limb lymphedema (ULL). There have been adaptations and validations in a number of different countries. While a German version of LYMQOL Leg for lower limb lymphedema is available, a validated translation of LYMQOL Arm to German is lacking. We aimed to perform a cross-cultural adaption and translation according to ISPOR principles. Methods: Patients suffering from ULL from Germany, Austria, and Switzerland (n = 52) were questioned twice using the translated LYMQOL Arm, SF-36, and an evaluation questionnaire. The assessment of the content validity and face validity proved this version of LYMQOL Arm to be acceptable for interviewing German-speaking patients with ULL in Germany. Results: Comparison of LYMQOL Arm and SF-36 demonstrated good construct validity. Test-retest reliability was moderate to good (intraclass correlation coefficients 0.66-0.73). Cronbach's alpha values varied between 0.79 and 0.89 in both interviews, indicating good internal consistency. Factor analysis revealed a cumulative variance of 59.5% for the four domains of the questionnaire. Conclusion: There was no significant association between lymphedema stage and LYMQOL Arm score. This trial tested the appropriateness of the German version of the LYMQOL Arm for measuring HRQoL in German-speaking individuals with ULL.

A Platform for Testing the Biocompatibility of Implants: Silicone Induces a Proinflammatory Response in a 3D Skin Equivalent.

Biocompatibility testing of materials is carried out in 2D cell cultures or animal models despite serious limitations. 3D skin equivalents are advanced in vitro models for human skin. Silicone has been shown to be noncytotoxic but capable of eliciting an immune response. Our aim was to (1) establish a 3D skin equivalent to (2) assess the proinflammatory properties of silicone. We developed a coculture of keratinocytes and fibroblasts resulting in a 3D skin equivalent with an implant using samples from a breast implant. Samples with and without the silicone implant were studied histologically and immunohistochemically in comparison to native human skin samples. Cytotoxicity was assessed via LDH-assay, and cytokine response was assessed via ELISA. Histologically, our 3D skin equivalents had a four-layered epidermal and a dermal component. The presence of tight junctions was demonstrated in immunofluorescence. The only difference in 3D skin equivalents with implants was an epidermal thinning. Implanting the silicone samples did not cause more cell death, however, an inflammatory cytokine response was triggered. We were able to establish an organotypical 3D skin equivalent with an implant, which can be utilised for studies on biocompatibility of materials. This first integration of silicone into a 3D skin equivalent confirmed previous findings on silicone being non-cell-toxic but capable of exerting a proinflammatory effect.

Diagnostical accuracy of hyperspectral imaging after free flap surgery.

Microsurgical free-tissue transfer has been a safe option for tissue reconstruction. This study aimed to analyze the diagnostic accuracy of hyperspectral imaging (HSI) after free-tissue transfer surgery. From January 2017 to October 2019, 42 consecutive free-flap surgeries were performed, and their outcomes were analyzed via HSI. Clinical examination of free-flap perfusion was initially performed. Clinical examination findings were subsequently compared with those of HSI. Potential venous congestion with subsequent necrosis was defined as a tissue hemoglobin index of ≥53%. Student's t-test was used to compare the results of the analysis. The evaluation of sensitivity and specificity for flap failure detection was time dependent using the Fisher's exact test. A p-value of ≤0.05 was considered statistically significant. Microsurgical tissue transfer success rate was 84%. Seven patients presented with venous congestion that caused total flap necrosis. Overall, 124 assessments were made. HSI accurately identified 12 out of 19 pathological images: four as false positive and seven as false negative. The sensitivity and specificity of HSI were 57 and 94%, respectively, compared to those of clinical examination that were 28 and 100%, respectively, within 24 h following tissue transfer. The sensitivity and specificity of HSI were 63 and 96%, respectively, compared to those of clinical examination that were 63 and 100%, respectively, within the first 72 h. A tissue hemoglobin index of ≥53% could predict venous congestion after free-flap surgery. HSI demonstrated higher sensitivity than clinical examination within the first 24 h; however, it was not superior compared to clinical findings within 72 h.

Organotypic 3D Co-Culture of Human Pleura as a Novel In Vitro Model of Staphylococcus aureus Infection and Biofilm Development.

Bacterial pleural infections are associated with high mortality. Treatment is complicated due to biofilm formation. A common causative pathogen is Staphylococcus aureus (S. aureus). Since it is distinctly human-specific, rodent models do not provide adequate conditions for research. The purpose of this study was to examine the effects of S. aureus infection on human pleural mesothelial cells using a recently established 3D organotypic co-culture model of pleura derived from human specimens. After infection of our model with S. aureus, samples were harvested at defined time points. Histological analysis and immunostaining for tight junction proteins (c-Jun, VE-cadherin, and ZO-1) were performed, demonstrating changes comparable to in vivo empyema. The measurement of secreted cytokine levels (TNF-α, MCP-1, and IL-1ß) proved host-pathogen interactions in our model. Similarly, mesothelial cells produced VEGF on in vivo levels. These findings were contrasted by vital, unimpaired cells in a sterile control model. We were able to establish a 3D organotypic in vitro co-culture model of human pleura infected with S. aureus resulting in the formation of biofilm, including host-pathogen interactions. This novel model could be a useful microenvironment tool for in vitro studies on biofilm in pleural empyema.