Ultrasound evaluation of bowel vasculopathy in systemic sclerosis

BACKGROUND

Gastrointestinal (GI) manifestations are frequent in systemic sclerosis (SSc) with an impact on quality of life and morbidity. Bowel vasculopathy is a key pathogenetic factor responsible for GI involvement.

OBJECTIVES

To compare abdominal ultrasound (US) and Color Doppler Ultrasonography (CDU) features of splanchnic vessels of SSc patients with healthy controls.

METHODS

The charts of SSc patients who underwent an abdominal US and CDU study were retrospectively analyzed. For Superior Mesenteric Artery (SMA) and Inferior Mesenteric Artery (IMA) caliber, Peak Systolic Velocity (PSV), Reverse Velocity (RV), End-Diastolic Velocity (EDV), Mean Velocity (mV), Blood-flow, Resistive Index (RI) and Pulsatility Index (PI) were recorded.

RESULTS

28 SSc patients and 28 controls were enrolled. In SSc, caliber of SMA was significantly smaller than in controls (5.75 ± 0.62 mm vs. 6.45 ± 0.60 mm, p < 0.0001 - p adj =0.0002). The flow study of SMA and IMA showed a significant reduction of RV (SMA: 7.25 ± 6.37 cm/s vs. 18.52 ± 6.16 cm/s, p < 0.0001 - p adj <0.0001; IMA: 2.69 ± 6.10 cm/s vs. 17.06 ± 5.75 cm/s, p < 0.0001 - p adj <0.0001) and PI (SMA: 3.33 ± 0.75 vs. 4.53 ± 1.03, p < 0.0001 - p adj =0.0002; IMA: 3.54 ± 0.95 vs. 6.08 ± 1.53, p < 0.0001 - p adj <0.0001) in SSc patients than controls.

CONCLUSION

involvement of splanchnic vessels in SSc may be non-invasively investigated with abdominal US and CDU. Morphological and functional changes of Doppler parameters observed in SMA and IMA clearly demonstrate that these vessels are affected by SSc vasculopathy.

The relevance of signal timing in human-robot collaborative manipulation

To achieve a seamless human-robot collaboration, it is crucial that robots express their intentions without perturbating or interrupting the task that a human partner is performing at that moment. Although it has not received much attention so far, this issue is important when robots assist humans in physical and manipulation tasks. The main question addressed here is whether there is a more appropriate time to inform a human partner that a robot is requesting to pass them an object. This question is posed in a reference scenario where human individuals are involved in a continuous pick-and-place task that cannot be interrupted. Our findings showed that providing a cue at the beginning of a reach-to-grasp movement could severely interfere with the ongoing human action, increasing the number of errors made by humans, slowing down and degrading the smoothness of their arm movement, and deflecting their gaze. These disruptive interferences strongly decreased, until they disappeared, when the robot provided the cue to the human partners shortly after the participants picked up an object, identifying this as the best signaling timing. The results of this work showed how the signaling timing may have a decisive influence on the performances of the human-robot teamwork and contribute to understanding the mechanisms underpinning the phenomenon of cognitive-motor interference in humans.

Dural Metastasis without Subdural Hematoma or Subdural Fluid Collection in a Patient with Signet Ring Cell Gastric Adenocarcinoma

Patient: Female, 39-year-old

Final Diagnosis: Dural metastasis in signet ring cell gastric adenocarcinoma

Symptoms: Confusion • generalized seizure • headache

Medication: —

Clinical Procedure: —

Specialty: General and Internal Medicine • Oncology

Intraoperative bowel cleansing tool in active locomotion capsule endoscopy

Capsule endoscopy (CE) can be considered an example of "disruptive technology" since it represents a bright alternative to traditional diagnostic methodologies. If compared with traditional endoscopy, bowel cleansing procedure in CE becomes of greater importance, due to the impossibility to intraoperatively operate on unclean gastrointestinal tract areas. Considering the promising results and benefits obtained in the field of CE for gastrointestinal diagnosis and intervention, the authors approached the bowel cleansing issue with the final aim to propose an innovative and easy-to-use intraoperative cleansing system to be applied to an active locomotion softly-tethered capsule device, already developed by the authors. The system, that has to be intended as an additional tool for intraoperatively cleansing procedure of the colonic tract, is composed by a flexible tube with a metallic deflector attached to the distal end; it can be headed to the target area through the capsule operating channel. Performances of the colonoscopic capsule and intraoperative cleansing capabilities were successfully confirmed both in an in-vitro and ex-vivo experimental session. The innovative intraoperative cleansing system demonstrated promising results in terms of water injection, colonic wall cleansing procedure and subsequent water suction, thus guaranteeing to reduce the risk of inadequate visualization of the mucosa in endoscopic procedures.

A computer-assisted robotic platform for Focused Ultrasound Surgery: Assessment of high intensity focused ultrasound delivery

In the last century, medicine showed considerable advancements in terms of new technologies, devices and diagnostic/therapeutic strategies. Those advantages led to a significant reduction of invasiveness and an improvement of surgical outcomes. In this framework, a computer-assisted surgical robotic platform able to perform non-invasive Focused Ultrasound Surgery (FUS) - the FUTURA platform - has the ambitious goal to improve accuracy, safety and flexibility of the treatment, with respect to current FUS procedures. Aim of this work is to present the current implementation of the robotic platform and the preliminary results about high intensity focused ultrasound (HIFU) delivery in in-vitro conditions, under 3D ultrasound identification and monitoring. Tests demonstrated that the average accuracy of the HIFU delivery is lower than 0.7 mm in both X and Y radial directions and 3.7 mm in the axial direction (Z) with respect to the HIFU transducer active surface.

Comparison of carotid artery blood velocity measurements by vector and standard Doppler approaches

Although severely affected by the angle dependency, carotid artery peak systolic velocity measurements are widely used for assessment of stenosis. In this study, blood peak systolic velocities in the common and internal carotid arteries of both healthy volunteers and patients with internal carotid artery stenosis were measured by two vector Doppler (VD) methods and compared with measurements obtained with the conventional spectral Doppler approach. Although the two VD techniques were completely different (using the transmission of focused beams and plane waves, respectively), the measurement results indicate that these techniques are nearly equivalent. The peak systolic velocities measured in 22 healthy common carotid arteries by the two VD techniques were very close (according to Bland-Altman analysis, the average difference was 3.2%, with limits of agreement of ± 8.6%). Application of Bland-Altman analysis to comparison of either VD technique with the spectral Doppler method provided a 21%-25% average difference with ± 13%-15% limits of agreement. Analysis of the results obtained from 15 internal carotid arteries led to similar conclusions, indicating significant overestimation of peak systolic velocity with the spectral Doppler method. Inter- and intra-operator repeatability measurements performed in a group of 8 healthy volunteers provided equivalent results for all of the methods (coefficients of variability in the range 2.7%-6.9%), even though the sonographers were not familiar with the VD methods. The results of this study suggest that the introduction of vector Doppler methods in commercial machines may finally be considered mature and capable of overcoming the angle-dependent overestimation typical of the standard spectral Doppler approach.

Biohumoral markers as predictor of right ventricular dysfunction in AL Amyloidosis

AIM

In AL amyloidosis, the importance of right ventricle (RV) involvement has recently been underlined and its role in predicting prognosis has been emphasized. Little is known about the relationship between RV involvement, N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin levels. Aim of our study was to clarify the relationship between NT-proBNP and troponin and RV involvement and analyze their independent value as predictors of RV dysfunction.

METHODS AND RESULTS

We examined 76 consecutive patients with biopsy-proven AL amyloidosis. Each patient received complete clinical evaluation, troponin I, NT-proBNP assay and comprehensive echocardiographic evaluation. Considering a tricuspidal annulus plane systolic excursion (TAPSE) value <16 mm, 23 patients (30%) presented RV systolic dysfunction, whereas 53 (70%) did not. Patient with reduced TAPSE had thicker left ventricle (LV) walls and RV free walls, reduced LV fractional shortening, impaired LV diastolic function and worse LV and RV myocardial performance index. For RV dysfunction the best predictive value for NT-proBNP was identified as 2977 ng/l with sensitivity and specificity of 87% and 84%, respectively; best cut-off for troponin I was identified as 0.085 ng/l, with sensitivity and specificity of 85% and 90% respectively. At multivariable logistic regression analysis, both NT-proBNP and troponin I emerged as independent predictors of RV dysfunction presence but troponin appears to have a higher predictive power.

CONCLUSION

Our study demonstrated that cut-off values of 2977 ng/ml for NT-proBNP and 0.085 ng/l for troponin were able to identify a subgroup of AL patients with RV dysfunction. Troponin I is more accurate and seems to be the best biohumoral marker of RV dysfunction.

Differences between internal jugular vein and vertebral vein flow examined in real time with the use of multigate ultrasound color Doppler

BACKGROUND AND PURPOSE

The hypothesis that MS could be provoked by a derangement of the blood outflow from the brain has been largely discredited. In part, it was because data on the normal pattern of outflow are scarce and obtained with different methods. The aim of this study was to evaluate the normal pattern of outflow for the vertebral and internal jugular veins in healthy subjects with multigate color Doppler.

MATERIALS AND METHODS

Twenty-five volunteers were studied to assess vessel area, mean velocity, and flow for the vertebral and internal jugular veins in the supine and sitting positions.

RESULTS

In the sitting position, flow decreases, both in vertebral veins and internal jugular veins, as the total vessel area decreases (from 0.46 ± 0.57 to 0.09 ± 0.08 cm(2)), even if the mean velocity increases (from 12.58 ± 10.19 to 24.14 ± 17.60 cm/s). Contrary to what happens to the blood inflow, outflow in the supine position, through vertebral and internal jugular veins, is more than twice the outflow in the sitting position (739.80 ± 326.32 versus 278.24 ± 207.94 mL/min). In the sitting position, on application of very low pressure to the skin with the sonography probe, internal jugular veins rarely appear to occlude. A pronounced difference of diameter between internal jugular veins was present in approximately one-third of subjects.

CONCLUSIONS

Our results support the view that other outflow pathways, like the vertebral plexus, play a major role in the normal physiology of brain circulation and must be assessed to obtain a complete picture of blood outflow.

Cardiac amyloidosis: the heart of the matter

Amyloidosis comprises a unique group of diseases that share in common the extracellular deposition of insoluble fibrillar proteins in organs and tissue including the heart. Cardiac amyloidosis could be primary a part of systemic acquired amyloidosis, or a result of heredofamilial amyloidosis. Although the infiltration of the heart from different types of amyloid results in restrictive cardiomyopathy that manifests with refractory congestive heart failure and conduction abnormalities, unequivocal identification of the deposited amyloidogenic protein is mandatory in order to avoid misdiagnosis and inappropriate treatment. Recent developments in imaging techniques and extracardiac tissue biopsy have minimized the need for invasive endomyocardial biopsy for amyloidosis. Despite advances in treatment, the prognosis of a patient with amyloidosis is still poor and depends upon the underlying disease, and the type and degree of dysfunction of the involved organs. Thus, early diagnosis is mandatory because patients with advanced disease are usually too ill for intensive therapy. This review outlines current approaches to diagnosis, assessment of disease severity, and treatment of cardiac amyloidosis.

The thrombophilic pattern of different clinical manifestations of venous thromboembolism: a survey of 443 cases of venous thromboembolism

Although pulmonary embolism (PE) and deep vein thrombosis (DVT) share many risk factors, it is uncertain whether thrombophilic abnormalities may impact differently on the development of these two clinical manifestations of venous thromboembolism (VTE). To give further insight into this issue, we estimated the association of PE with different types of thrombophilia and evaluated whether these abnormalities have a different prevalence in patients presenting with PE, alone or associated with DVT, as compared with those with isolated DVT. In this study 443 consecutive patients with a first episode of VTE and 304 matched healthy controls underwent laboratory screening for thrombophilia, including natural anticoagulants, factor V Leiden and prothrombin G20210A polymorphisms, antiphospholipid antibodies, homocysteine, factor VIII, and lipoprotein(a). Of the 443 patients, 224 patients had isolated DVT, 144 had combined DVT/PE, and 75 had isolated PE. At least one thrombophilic abnormality was detected in 72.8% of DVT, 66% of DVT/EP, and 60% of isolated PE patients. A high prevalence of hyperhomocysteinemia and elevated lipoprotein(a) levels was found in all patients with no significant differences among the three groups. The prevalence of prothrombin G20210A polymorphism and of elevated factor VIII levels was significantly higher in patients with DVT and DVT/PE than in controls, but not in those with isolated PE, whereas factor V Leiden polymorphism was associated with isolated DVT but not with DVT/PE or isolated PE. In conclusion, the thrombophilic burden seems different in isolated PE versus DVT with or without PE, suggesting that PE may encompass a different pathophysiological process of thrombosis to DVT.

[Severe recurrent intrahepatic cholestasis in systemic AL amyloidosis without obvious liver involvement: unexplained hepatic toxicity or a case of misdiagnosed liver amyloidosis?]

We report the case of a 50-year-old woman who was admitted to the hospital for acute abdominal pain with nephrotic proteinuria, rapidly progressive renal failure, and moderate anemia. Laboratory tests showed mild Bence Jones (λ) proteinuria with negative serum immunofixation and a mild increase in λ free light chains. A bone marrow biopsy and a fat tissue aspirate showed multiple myeloma and amyloidosis. Because of the end-stage renal disease, the patient began regular dialysis treatment and was started on bortezomib 1.3 mg/m2 plus dexamethasone 40 mg on days 1, 4, 8 and 11 of 21-day cycles. Ten days later she complained of a new episode of abdominal pain with jaundice. A CT scan and an MRI scan ruled out all secondary causes of cholangitis including cancer. Acute intrahepatic cholestasis due to amyloid deposition was then hypothesized. After 4 well tolerated cycles of bortezomib and dexamethasone, blood tests showed a complete hematological response with full reversal of cholestasis. After three months, a new episode of abdominal pain occurred and this time the patient was operated on and found to have an intestinal volvulus. Because of the jaundice, a transjugular liver biopsy was performed showing no evidence of amyloid deposits. Two months later the patient died of septic shock. Although no autopsy was performed and the ultimate cause of the cholestasis could not be ascertained, amyloidosis remains the major culprit in this unfortunate case.

Magnetic air capsule robotic system: proof of concept of a novel approach for painless colonoscopy

BACKGROUND

Despite being considered the most effective method for colorectal cancer diagnosis, colonoscopy take-up as a mass-screening procedure is limited mainly due to invasiveness, patient discomfort, fear of pain, and the need for sedation. In an effort to mitigate some of the disadvantages associated with colonoscopy, this work provides a preliminary assessment of a novel endoscopic device consisting in a softly tethered capsule for painless colonoscopy under robotic magnetic steering.

METHODS

The proposed platform consists of the endoscopic device, a robotic unit, and a control box. In contrast to the traditional insertion method (i.e., pushing from behind), a "front-wheel" propulsion approach is proposed. A compliant tether connecting the device to an external box is used to provide insufflation, passing a flexible operative tool, enabling lens cleaning, and operating the vision module. To assess the diagnostic and treatment ability of the platform, 12 users were asked to find and remove artificially implanted beads as polyp surrogates in an ex vivo model. In vivo testing consisted of a qualitative study of the platform in pigs, focusing on active locomotion, diagnostic and therapeutic capabilities, safety, and usability.

RESULTS

The mean percentage of beads identified by each user during ex vivo trials was 85 ± 11%. All the identified beads were removed successfully using the polypectomy loop. The mean completion time for accomplishing the entire procedure was 678 ± 179 s. No immediate mucosal damage, acute complications such as perforation, or delayed adverse consequences were observed following application of the proposed method in vivo.

CONCLUSIONS

Use of the proposed platform in ex vivo and preliminary animal studies indicates that it is safe and operates effectively in a manner similar to a standard colonoscope. These studies served to demonstrate the platform's added advantages of reduced size, front-wheel drive strategy, and robotic control over locomotion and orientation.

Robotic versus manual control in magnetic steering of an endoscopic capsule

BACKGROUND AND STUDY AIMS

Capsular endoscopy holds promise for the improved inspection of the gastrointestinal tract. However, this technique is limited by a lack of controlled capsule locomotion. Magnetic steering has been proposed by the main worldwide suppliers of commercial capsular endoscopes and by several research groups. The present study evaluates and discusses how robotics may improve diagnostic outcomes compared with manual magnetic steering of an endoscopic capsule.

MATERIALS AND METHODS

An endoscopic capsule prototype incorporating permanent magnets was deployed in an ex vivo colon segment. An operator controlled the external driving magnet manually or with robotic assistance. The capsule was maneuvered through the colon, visualizing and contacting targets installed on the colon wall. Procedure completion time and number of targets reached were collected for each trial to quantitatively compare manual versus robotic magnetic steering ( T-test analysis with P = 0.01). Then, through a set of in vivo animal trials, the efficacy of both approaches was qualitatively assessed.

RESULTS

In ex vivo conditions, robotic-assisted control was superior to manual control in terms of targets reached (87 % +/- 13 % vs 37 % +/- 14 %). Manual steering demonstrated faster trial completion time (201 +/- 24 seconds vs 423 +/- 48 seconds). Under in vivo conditions, the robotic approach confirmed higher precision of movement and better reliability compared with manual control.

CONCLUSIONS

Robotic control for magnetic steering of a capsular endoscope was demonstrated to be more precise and reliable than manual operation. Validation of the proposed robotic system paves the way for automation of capsular endoscopy and advanced endoscopic techniques.