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In the current study, we evaluated whether neoadjuvant chemoradiotherapy with reduced treatment volumes due to the exclusion of elective pelvic nodal irradiation is a feasible strategy for selected patients with locally advanced rectal cancer. Patients with T2 low-lying/T3, N0-N1 rectal lesions without evidence of disease in the lateral lymph nodes were prospectively recruited. All patients underwent pretreatment testing, including computed tomography imaging of the chest, abdomen, and pelvis with intravenous contrast, pelvic magnetic resonance imaging with intravenous contrast, and 18-fluorodeoxyglucose positron emission/computed tomography. The clinical target volume included the primary tumor and the mesorectum with vascular supply containing the perirectal and presacral nodes, with the upper border at the S2/S3 interspace. The total radiation dose was 50.4 Gy, and fluoropyrimidine-based chemotherapy was associated concomitantly. The primary endpoint of the study was the reduction of gastrointestinal (GI) toxicity, and the secondary endpoints were pathologic complete response, local control, overall survival, and disease-free survival. Fifty-two patients (30 men, 22 women) with a median age of 67 years (range, 45-85 years) were enrolled in the study. Acute grade 3 GI toxicity was 7.6%, and there were no cases of grade 4 toxicity. Three patients (5.7%) developed a local recurrence. No relapse occurred in the lateral lymph nodes. The local control rate at 5 years was 96.1%. With a median follow-up time of 72.9 months (range, 2.5-127.6 months), the 3- and 5-year overall survival rates were 89.4% and 87%, respectively. The 3- and 5-year disease-free survival rates were 82.4% and 82.4%, respectively. De-escalation of radiation therapy target volume reduces GI side effects without compromising efficacy in patients with rectal cancer. These results cannot be clearly extended to high-risk disease and need further evaluation in future randomized trials. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The purpose of this study is to verify the effectiveness and complications occurrence of radiofrequency ablation (RFA) in the treatment of osteoid osteoma (OO) in non-operating room anesthesia (N.O.R.A.). PATIENTS AND METHODS: From 2014 to 2017, 61 patients affected by OO (40 men and 21 women) with an age of 20.7 years on average (range, 4-51 years; 12 patients aged 20 years or younger) underwent computed tomography-guided percutaneous radiofrequency ablation (RFA) in N.O.R.A. (Non-Operating Room Anesthesia). Lesion sites treated were: femur (27), tibia (22), pelvis (2), talar bone (3), distal radius (1), and humerus (6). Mean follow-up time was 36 months. In each case, anesthesiologic support followed a new protocol (N.O.R.A. protocol), approved by our Institute. Primary success rate, complications, symptom-free intervals, and follow-up results were evaluated. RESULTS: Pain relief (evaluated with Visual Analogue Scale -- VAS) was significant in 97% of patients; it disappeared within 24 hours of the procedure in 44 patients, within 3 days in 10 patients, and within 7 days in 7 patients. After 6 months of observation time, 60 of 61 patients were successfully treated and had no more complaints. In 2 patients, two major complications were found: infection of the site treated, healed with antibiotics, and a nerve lesion, healed with steroid therapy. No other complications were observed. CONCLUSIONS: RFA is a highly effective, efficient, minimally invasive and safe method for the treatment of OO following N.O.R.A. protocol. [ABSTRACT FROM AUTHOR]

Objective The aim of the present study was to assess the temperature map and its reproducibility while applying two different MWA systems (915 MHz vs 2.45 GHz) in ex vivo porcine livers. Materials and methods Fifteen fresh pig livers were treated using the two antennae at three different settings: treatment time of 10 min and power of 45 W for both systems; 4 min and 100 W for the 2.45 GHz system. Trends of temperature were recorded during all procedures by means of fiber optic-based probes located at five fixed distances from the antenna, ranging between 10 mm and 30 mm. Each trial was repeated twice to assess the reproducibility of temperature distribution. Results Temperature as function of distance from the antenna can be modeled by a decreasing exponential trend. At the same settings, temperature obtained with the 2.45 GHz system was higher than that obtained with the 915 MHz thus resulting into a wider area of ablation (diameter 17 mm vs 15 mm). Both systems showed good reproducibility in terms of temperature distribution (root mean squared difference for both systems ranged between 2.8 °C and 3.4 °C). Conclusions When both MWA systems are applied, a decreasing exponential model can predict the temperature map. The 2.45 GHz antenna causes higher temperatures as compared to the 915 MHz thus, resulting into larger areas of ablation. Both systems showed good reproducibility although better results were achieved with the 2.45 GHz antenna. [ABSTRACT FROM AUTHOR]

Bone metastases can be treated by interventional radiologists with a minimally invasive approach. Such treatments are performed percutaneously under radiological imaging guidance. Different interventional techniques can be applied with curative or palliative intent depending on lesions and patients' status. In the whole, available interventional techniques are distinguished into “ablative” and “consolidative”. Ablative techniques achieve bone tumor necrosis by dramatically increasing or decreasing intra-tumoral temperature. This option can be performed in order to alleviate pain or to eradicate the lesion. On the other hand, consolidative techniques aim at obtaining bone defect reinforcement mainly to alleviate pain and prevent pathological fractures. We herein present evidence supporting the application of each different interventional technique, as well as common strategies followed by interventional radiologists while approaching bone metastases. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate bone density changes at the level of normal bone and bone metastases after zoledronic acid (ZA) treatment in oncologic patients. Materials and methods: We retrospectively evaluated 72 consecutive adult patients with histologically confirmed solid tumors with at least 1 newly diagnosed bone metastatic lesion. Bone metastases were diagnosed by bone scans and confirmed with computed tomography (CT). Patients received intravenous ZA, 4mg, by 15-min infusion every 28 day through a peripheral or a central venous access and were monitored for at least 3 months and a maximum of 24 months. Bone density was determined at the level of bone metastases and at the level of normal trabecular and cortical bone using a ROI-based approach. Results: A significant increase was demonstrated at the level of normal trabecular bone of the calvarium and the femoral neck. No significant increase of density was observed at the level of the normal cortical bone. Bone metastases showed a significant increase in CT density as compared to baseline up to 24 months after zoledronic acid. Conclusion: We have found that long term treatment with ZA increases trabecular bone density in oncologic patients whereas normal cortical bone changes are not detectable. [Copyright &y& Elsevier]

We present the case of an 83-year-old woman with an isolated bilateral middle cerebellar peduncles stroke caused by complete occlusion of the right vertebral artery and focal occlusion of the left vertebral artery due to giant cell arteritis. The diagnosis was achieved by integrating MRI, ultrasound study, laboratory data and subsequent pathology analysis after biopsy of the temporal artery. [ABSTRACT FROM AUTHOR]

A systematic review of the clinical safety and efficacy of percutaneous breast cancer cryoablation was performed. Of 202 papers screened, seven matched the inclusion criteria. Cryoablation was mainly performed under ultrasound guidance, and on average two cryoprobes were used. Complete local tumor control was noted in 73% of patients (mean follow-up, 8 mo). No major complications were noted. The cosmetic outcome was satisfactory. Breast cancer cryoablation is safe, although local tumor control is suboptimal. The best results are achieved with small (<15 mm) ductal tumors treated by application of multiple cryoprobes. [ABSTRACT FROM AUTHOR]

The study of bio-inspired structures and their reproduction has always fascinated humans. The advent of soft robotics, thanks to soft materials, has enabled considerable progress in this field. Over the years, polyps, worms, cockroaches, jellyfish, and multiple anthropomorphic structures such as hands or limbs have been reproduced. These structures have often been used for gripping and handling delicate objects or those with complex unknown a priori shapes. Several studies have also been conducted on grippers inspired by the seahorse tail. In this paper, a novel biomimetic soft pneumatic actuator inspired by the tail of the seahorse Hippocampus reidi is presented. The actuator has been developed to make a leg to sustain a multi-legged robot. The prototyping of the actuator was possible by combining a 3D-printed reinforcement in thermoplastic polyurethane, mimicking the skeletal apparatus, within a silicone rubber structure, replicating the functions of the external epithelial tissue. The latter has an internal channel for pneumatic actuation that acts as the inner muscle. The study on the anatomy and kinematic behaviour of the seahorse tail suggested the mechanical design of the actuator. Through a test campaign, the actuator prototype was characterized by isotonic tests with an external null load, isometric tests, and activation/deactivation times. Specifically, the full actuator distension of 154.5 mm occurs at 1.8 bar, exerting a maximum force of 11.9 N, with an activation and deactivation time of 74.9 and 94.5 ms, respectively.

This paper illustrates an experimental activity for the closed-loop position control of an actuator made using shape memory alloy (SMA) wire. A solution with the self-sensing effect was implemented to miniaturize the systems, i.e., without external sensors. A proportional control algorithm was initially used, demonstrating the idea's feasibility; the wire can behave simultaneously as an actuator and sensor. An experimental investigation was subsequently conducted for the optimization of the developed actuator. As for the material, a Flexinol wire, Ni-Ti alloy, with a diameter of 0.150 mm and a length of 200 mm, was used. Preliminarily, characterization of the SMA wire at constant and variable loads was carried out; the characteristics detected were elongation vs. electric current and elongation vs. electrical resistance. The control system is PC based with a data acquisition card (DAQ). A drive board was designed and built to read the wire's electrical resistance and power it by pulse width modulation (PWM). A notable result is that the actuator works with good precision and in dynamic conditions, even when it is called to support a load up to 65% different from that for which the electrical resistance-length correlation has previously been experimentally obtained, on which the control is based. This opens up the possibility of using the actuator in a counteracting configuration with a spring, which makes hardware implementation and control management simple.

This paper reports on the design, implementation, and characterization of a current-mode analog-front-end circuit for capacitance-to-voltage conversion that can be used in connection with a large variety of sensors and actuators in industrial and rehabilitation medicine applications. The circuit is composed by: (i) an oscillator generating a square wave signal whose frequency and pulse width is a function of the value of input capacitance; (ii) a passive low-pass filter that extracts the DC average component of the square wave signal; (iii) a DC-DC amplifier with variable gain ranging from 1 to 1000. The circuit has been designed in the current-mode approach by employing the second-generation current conveyor circuit, and has been implemented by using commercial discrete components as the basic blocks. The circuit allows for gain and sensitivity tunability, offset compensation and regulation, and the capability to manage various ranges of variations of the input capacitance. For a circuit gain of 1000, the measured circuit sensitivity is equal to 167.34 mV/pF with a resolution in terms of capacitance of 5 fF. The implemented circuit has been employed to measure the variations of the capacitance of a McKibben pneumatic muscle associated with the variations of its length that linearly depend on the circuit output voltage. Under step-to-step conditions of movement of the pneumatic muscle, the overall system sensitivity is equal to 70 mV/mm with a standard deviation error of the muscle length variation of 0.008 mm.

In this paper, the design of a 2-dof (degrees of freedom) rehabilitation robot for upper limbs driven by pneumatic muscle actuators is presented. This paper includes the different aspects of the mechanical design and the control system and the results of the first experimental tests. The robot prototype is constructed and at this preliminary step a position and trajectory control by fuzzy logic is implemented. The pneumatic muscle actuators used in this arm are designed and constructed by the authors' research group.

This paper describes the results of research projects developed at the University of L'Aquila by the research group of the authors in the field of biomedical engineering, which have seen an important use of additive manufacturing technologies in the prototyping step and, in some cases, also for the realization of preindustrialization prototypes. For these projects, commercial 3D printers and technologies such as fused deposition modelling (FDM) were used; the most commonly used polymers in these technologies are acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). The research projects concern the development of innovative actuators, such as pneumatic muscles and soft pneumatic actuators (SPAs), the development of active orthoses, such as a lower limb orthosis and, finally, the development of a variable-stiffness grasper to be used in natural orifice transluminal endoscopic surgery (NOTES). The main aspects of these research projects are described in the paper, highlighting the technologies used such as the finite element analysis and additive manufacturing.

The emerging demographic trends toward an aging population, demand new ways and solutions to improve the quality of elderly life. These include, prolonged independent living, improved health care, and reduced social isolation. Recent technological advances in the field of assistive robotics bring higher sophistication and various assistive abilities that can help in achieving these goals. In this paper, we present design and validation of a low-cost telepresence robot that can assist the elderly and their professional caregivers, in everyday activities. The developed robot structure and its control objectives were tested in, both, a simulation and experimental environment. On-field experiments were done in a private elderly care center involving elderly persons and caregivers as participants. The goal of the evaluation study was to test the software architecture and the robot capabilities for navigation, as well as the robot manipulator. Moreover, participants' reactions toward a possible adoption of the developed robot system in everyday activities were assessed. The obtained results of the conducted evaluation study are also presented and discussed.