Advancements in reconstructive microsurgery have evolved into supermicrosurgery; connecting vessels with diameter between 0.3 and 0.8 mm for reconstruction of lymphatic flow and vascularized tissue transplantation. Supermicrosurgery is limited by the precision and dexterity of the surgeon's hands. Robot assistance can help overcome these human limitations, thereby enabling a breakthrough in supermicrosurgery. We report the first-inhuman study of robot-assisted supermicrosurgery using a dedicated microsurgical robotic platform. A prospective randomized pilot study is conducted comparing robot-assisted and manual supermicrosurgical lymphatico-venous anastomosis (LVA) in treating breast cancer-related lymphedema. We evaluate patient outcome at 1 and 3 months post surgery, duration of the surgery, and quality of the anastomosis. At 3 months, patient outcome improves. Furthermore, a steep decline in duration of time required to complete the anastomosis is observed in the robot-assisted group (33-16 min). Here, we report the feasibility of robot-assisted supermicrosurgical anastomosis in LVA, indicating promising results for the future of reconstructive supermicrosurgery.

We propose a new definition for erosions visualized with HR-pQCT imaging. Interreader reliability for erosion detection is good, but further refinement of selection of landmarks for erosion size measurement, or automated volumetric methods, will be pursued.

Advanced microsurgical procedures are currently limited by human precision and manual dexterity. The potential of robotics in microsurgery is highlighted, including a general overview of applications of robotic assistance in microsurgery and its introduction in different surgical specialties. A new robotic platform especially designed for (super) microsurgery is presented. Results of an in vivo animal study underline its feasibility and encourage further development toward clinical studies. Future directions of robotic microsurgery are proposed.

Background: Lymphaticovenous anastomosis, a supermicrosurgical technique, creates bypasses between the lymphatic and venous systems. The quality of lymphaticovenous anastomosis depends on the surgeon's dexterity and precision, and is subject to imperfections caused by the physiologic tremor of the human hand. A dedicated robot for microsurgery has been created to overcome these limitations (MUSA, MicroSure, Eindhoven, The Netherlands). This study describes 1-year clinical outcomes of the first-in-human trial of robot-assisted and manual lymphaticovenous anastomosis in patients with breast cancer-related lymphedema. Methods: In this prospective pilot study, women with breast cancer-related lymphedema were randomized into the robot-assisted or manual lymphaticovenous anastomosis group. Outcomes were quality of life, arm circumference, conservative treatment frequency, arm dermal backflow stage, and anastomosis patency. Results: Twenty women were included, of whom eight underwent robot-assisted lymphaticovenous anastomosis surgery and 12 underwent manual surgery. In both groups, quality of life significantly improved at 12 months (robot-assisted surgery, p = 0.045; manual surgery, p = 0.001). Arm circumference did not decrease (robot-assisted surgery, p = 0.094; manual surgery, p = 0.240). Daily use of compression garments decreased by 61.9 percent (robot-assisted surgery) and 70.2 percent (manual surgery). The frequency of manual lymphatic drainage remained similar compared with baseline. Arm dermal backflow stage was reduced in one patient in the robot-assisted group and in five cases in the manual group. Overall, 76.5 percent of the anastomoses were patent (robotassisted surgery, 66.6 percent; manual surgery, 81.8 percent). Conclusions: After evaluating 1-year follow-up data, this study confirms the feasibility of robot-assisted lymphaticovenous anastomosis surgery. Clinical outcomes were comparable between robot-assisted and manual lymphaticovenous anastomosis. This encourages further research using the new microsurgical robot MUSA for lymphaticovenous anastomosis and other (super)microsurgical procedures.

BackgroundTo study the reliability and validity of high-resolution peripheral quantitative CT (HR-pQCT) with microCT (μCT) as gold standard in the visual detection of cortical breaks in metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints.MethodsTen cadaveric fingers (10 MCP and 9 PIP joints) were imaged by HR-pQCT and μCT and visually analyzed by two independent readers. Intra- and interreader reliability were evaluated for the presence (yes/no, kappa statistics) and the total number (intraclass correlation coefficient, ICC) of cortical breaks. Sensitivity, specificity, positive and negative predictive value (PPV respectively NPV) of HR-pQCT in detecting cortical breaks were calculated.ResultsWith HR-pQCT, mean 149 cortical breaks were identified and with μCT mean 129 (p < 0.05). Intrareader reliability for the presence of a cortical break per quadrant was 0.52 (95 % CI 0.48–0.56) and 0.71 (95 % CI 0.67–0.75) for HR-pQCT and μCT, respectively, and for the total number of cortical breaks 0.61 (95 % CI 0.49–0.70) and 0.75 (95 % CI 0.68–0.82). Interreader reliability for the presence of a cortical break per quadrant was 0.37 (95 % CI 0.33–0.41) and 0.45 (95 % CI 0.41–0.49) for HR-pQCT and μCT, respectively, and for the number of cortical breaks 0.55 (95 % CI 0.43–0.65) and 0.54 (95 % CI 0.35–0.67). Sensitivity, specificity, PPV and NPV of HR-pQCT were 81.6, 64.0, 81.6, and 64 % respectively.ConclusionCortical breaks were commonly visualized in MCP and PIP joints with HR-pQCT and μCT. Reliability of both HR-pQCT and μCT was fair to moderate. HR-pQCT was highly sensitive to detect cortical breaks with μCT as gold standard.Electronic supplementary materialThe online version of this article (doi:10.1186/s12891-016-1148-y) contains supplementary material, which is available to authorized users.

Small cortical interruptions may be the first sign of an erosion, and more interruptions can be found in patients with rheumatoid arthritis (RA) compared with healthy subjects. First, we compared the number and size of interruptions in patients with RA with healthy subjects using high-resolution peripheral quantitative CT (HR-pQCT). Second, we investigated the association between structural damage and inflammatory markers on conventional radiography (CR) and MRI with interruptions on HR-pQCT. Third, the added value of HR-pQCT over CR and MRI was investigated. The finger joints of 39 patients with RA and 38 healthy subjects were examined through CR, MRI, and HR-pQCT. CRs were scored using the Sharp/Van der Heijde method. MRI images were analyzed for the presence of erosions, bone marrow edema, and synovitis. HR-pQCT images were analyzed for the number, surface area, and volume of interruptions using a semiautomated algorithm. Descriptives were calculated and associations were tested using generalized estimating equations. Significantly more interruptions and both a larger surface area and the volume of interruptions were detected in the metacarpophalangeal joints of patients with RA compared with healthy subjects (median, 2.0, 1.42 mm , and 0.48 mm versus 1.0, 0.69 mm , and 0.23 mm , respectively; all p < 0.01). Findings on CR and MRI were significantly associated with more and larger interruptions on HR-pQCT (prevalence ratios [PRs] ranging from 1.03 to 7.74; all p < 0.01) in all subjects, and were consistent in patients with RA alone. Having RA was significantly associated with more and larger interruptions on HR-pQCT (PRs, 2.33 to 5.39; all p < 0.01), also after adjustment for findings on CR or MRI. More and larger cortical interruptions were found in the finger joints of patients with RA versus healthy subjects, also after adjustment for findings on CR or MRI, implying that HR-pQCT imaging may be of value in addition to CR and MRI for the evaluation of structural damage in patients with RA. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.

Objectives The purpose of the study was to prospectively investigate change (repair or progression) in the number, surface area and volume of cortical interruptions, bone density (vBMD) and micro-structural parameters assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT) in finger joints of patients with rheumatoid arthritis (RA) treated with synthetic disease modifying anti-rheumatic drugs (sDMARDs) and/or biologic DMARDs (bDMARDs) over a 1-year follow-up period, and in comparison with healthy subjects (HS). Methods Thirty-two patients with RA (221 joints, 53% on bDMARDs) and 32 HS (117 joints) were assessed at baseline and after 1 year using semi-automatic analysis of HR-pQCT images. Mean changes (group level) and the proportion of joints (joint level) with changes beyond the least significant change were calculated. Results At baseline, 530 interruptions were identified in patients, and 136 in HS. The mean of the interruption parameters did not significantly change in either group Mean vBMD decreased more in patients than in HS (− 4.4 versus − 1.1 mgHA/ cm 3 , respectively). In patients versus HS, proportionally more joints showed repair in interruption volume (6.6% versus 1.7%, respectively) and loss of vBMD (26.7% versus 12.9%, respectively). In patients on sDMARDs versus patients on bDMARDs, proportionally more joints showed progression in the number of interruptions and loss of vBMD (6.1% versus 1.8% and 31.3% versus 17.2%, respectively). Conclusions HR-pQCT is able to quantify bone repair and progression. Cortical interruption-, vBMD-, and micro-structure were impaired in RA, of which vBMD and micro-structure further deteriorated, particularly in patients on sDMARDs.

ObjectivesTo introduce a fully-automated algorithm for the detection of small cortical interruptions (≥0.246mm in diameter) on high resolution peripheral quantitative computed tomography (HR-pQCT) images, and to investigate the additional value of manual correction of the automatically obtained contours (semi-automated procedure).MethodsTen metacarpophalangeal joints from seven patients with rheumatoid arthritis (RA) and three healthy controls were imaged with HR-pQCT. The images were evaluated by an algorithm according to the fully- and semi-automated procedure for the number and surface of interruptions per joint. Reliability between the fully- and semi-automated procedure and between two independent operators was tested using intra-class correlation coefficient (ICC) and the proportion of matching interruptions. Validity of single interruptions detected was tested by comparing it to visual scoring, as gold standard. The positive predictive value (PPV) and sensitivity were calculated.ResultsThe median number of interruptions per joint was 14 (range 2 to 59) and did not significantly differ between the fully- and semi-automated procedure (p = 0.37). The median interruption surface per joint was significantly higher with the fully- vs. semi-automated procedure (respectively, 8.6mm2 vs. 5.8mm2 and 6.1mm2, p = 0.01). Reliability was almost perfect between the fully- and semi-automated procedure for both the number and surface of interruptions (ICC≥0.95) and the proportion of matching interruptions was high (≥76%). Also the inter-operator reliability was almost perfect (ICC≥0.97, proportion of matching interruptions 92%). The PPV ranged from 27.6% to 29.9%, and sensitivity from 69.7% to 76.3%. Most interruptions detected with the algorithm, did show an interruption on a 2D grayscale image. However, this interruption did not meet the criteria of an interruption with visual scoring.ConclusionThe algorithm for HR-pQCT images detects cortical interruptions, and its interruption surface. Reliability and validity was comparable for the fully- and semi-automated procedures. However, we advise the use of the semi-automated procedure to assure quality. The algorithm is a promising tool for a sensitive and objective assessment of cortical interruptions in finger joints assessed by HR-pQCT.