Automatic Multiview Alignment of RGB-D Range Maps of Upper Limb Anatomy.

Digital representations of anatomical parts are crucial for various biomedical applications. This paper presents an automatic alignment procedure for creating accurate 3D models of upper limb anatomy using a low-cost handheld 3D scanner. The goal is to overcome the challenges associated with forearm 3D scanning, such as needing multiple views, stability requirements, and optical undercuts. While bulky and expensive multi-camera systems have been used in previous research, this study explores the feasibility of using multiple consumer RGB-D sensors for scanning human anatomies. The proposed scanner comprises three Intel® RealSenseTM D415 depth cameras assembled on a lightweight circular jig, enabling simultaneous acquisition from three viewpoints. To achieve automatic alignment, the paper introduces a procedure that extracts common key points between acquisitions deriving from different scanner poses. Relevant hand key points are detected using a neural network, which works on the RGB images captured by the depth cameras. A set of forearm key points is meanwhile identified by processing the acquired data through a specifically developed algorithm that seeks the forearm's skeleton line. The alignment process involves automatic, rough 3D alignment and fine registration using an iterative-closest-point (ICP) algorithm expressly developed for this application. The proposed method was tested on forearm scans and compared the results obtained by a manual coarse alignment followed by an ICP algorithm for fine registration using commercial software. Deviations below 5 mm, with a mean value of 1.5 mm, were found. The obtained results are critically discussed and compared with the available implementations of published methods. The results demonstrate significant improvements to the state of the art and the potential of the proposed approach to accelerate the acquisition process and automatically register point clouds from different scanner poses without the intervention of skilled operators. This study contributes to developing effective upper limb rehabilitation frameworks and personalized biomedical applications by addressing these critical challenges.

Strategies to decrease morbidity in surgical management of esophageal cancer: a single center experience.

BACKGROUND: In this study we described our experience in decreasing morbidity by performing a few changes during and after the Ivor Lewis esophagectomy. METHODS: This is a retrospective single center experience comparing a control period (group A) and a study period (group B) in patients who underwent esophagectomy for esophageal cancer (control group: 23; study group: 17). Control group had postero-lateral thoracotomy and a gastric tube without aspiration during postoperative period. Study group had limited lateral muscle sparing thoracotomy and postoperatively the gastric tube was routinely left for 1 week with intermittent aspiration (10 times every two hours for 1 week). RESULTS: Average operation time was 312±56 minutes in control period, in study period 189±36 min. Average ICU stay was 10 (7-32) days in the control group, in study group 4 (1-8) days. Anastomotic leak rate was significantly higher in control vs. study group (53.3% vs. 16.6%; P<0.05). Respiratory complications were significantly lower in the study group (47.8% vs. 17.6%). CONCLUSIONS: The combination of a limited lateral thoracotomy and postoperative intermittent aspiration seem to reduce the rate of respiratory and anastomotic complication after Ivor-Lewis' procedure.

An automatic method for feature segmentation of human thoracic and lumbar vertebrae.

BACKGROUND AND OBJECTIVE: Because of the three-dimensional distribution of morphological features of human vertebrae and the whole spine, in recent years, to make more precise diagnoses and to design optimized surgical procedures, new protocols have been proposed based on analysing their three-dimensional (3D) models. In the related literature, processes of segmentation and morphological features recognition are essentially performed by a skilled operator that selects the interesting areas. So, being affected by the preparation and experience of the operator, this produces an evaluation that is poorly reproducible and repeatable for the uncertainties of a typical manual measurement process. METHODS: To overcome this limitation, in this paper a new automatic method is proposed for feature segmentation and recognition of human vertebrae. The proposed computer-based method, starting from 3D high density discretized models of thoracic and lumbar vertebrae, automatically performs both the semantic and geometric segmentation of their morphological features. The segmentation and recognition rules codify some important definitions used in the traditional manual method, considering all the vertebra morphology information that is invariant inter-subject. RESULTS: The automatic method proposed here is verified by analysing many real vertebrae, both acquired using a 3D scanner and coming from Computerized Tomography (CT) scans. The obtained results are critically discussed and compared with the traditional manual methods for vertebra analysis. The method has proven to be robust and reliable in the segmentation and recognition of morphological features of vertebrae. Furthermore, the proposed automatic method avoids the blurring of quantitative parameters get from vertebrae, resulting from poor repeatability and reproducibility of manual methods used in the state-of-the-art. CONCLUSIONS: Starting from the automatic segmentation and recognition here proposed, it is possible to automatically calculate the parameters of thoracic or lumbar vertebrae used in archaeology, medicine, or biomechanics or define their new ones.

Retrospective case-control study on the outcomes of early minimally invasive pleural lavage for pleural empyema in oncology patients.

BACKGROUND: Oncology patients carry a substantial risk of developing pleural empyema. Here, we report the preliminary results of our early video-assisted thoracoscopic surgery (VATS) lavage strategy in cases of empyema occurring in patients undergoing (radio-) chemotherapy. METHODS: This was a retrospective case-control study comparing early VATS lavage (test group, current therapy since January 2018, n = 46) versus VATS pleurectomy (historical control; before January 2018, n = 46). RESULTS: Five patients in the control group and one in the test group developed recurrence of empyema within 30 days. Complications were more severe and more frequently observed in the historical control group than in the test group (30/46 vs. 12/46 CI: 5%-95%, p = < 0.05). Early VATS lavage saved operating time, allowed a shorter ICU stay (2.6 days CI: 5%-95% vs. 5.1 days CI: 5%-95%, p = ns) and an earlier hospital discharge (6.1 days CI: 5%-95% vs. 13.5 days CI: 5%-95%, p < 0.05). Moreover, radio and/or chemotherapy could be reinitiated earlier (15 ± 20.5 days CI: 5%-95% vs. 40 ± 12 days CI: 5%-95%, p < 0.05). CONCLUSIONS: In this retrospective cohort study, early VATS lavage was found to have a beneficial effect especially on hospital stay and enabling an earlier restart of radio- and/or chemotherapy.

A 3D Informational Database for Automatic Archiving of Archaeological Pottery Finds.

From archaeological excavations, huge quantities of material are recovered, usually in the form of fragments. Their correct interpretation and classification are laborious and time-consuming and requires measurement, analysis and comparison of several items. Basing these activities on quantitative methods that process 3D digital data from experimental measurements allows optimizing the entire restoration process, making it faster, more accurate and cheaper. The 3D point clouds, captured by the scanning process, are raw data that must be properly processed to be used in automatic systems for the analysis of archeological finds. This paper focuses on the integration of a shape feature recognizer, able to support the semantic decomposition of the ancient artifact into archaeological features, with a structured database, able to query the large amount of information extracted. Through the automatic measurement of the dimensional attributes of the various features, it is possible to facilitate the comparative analyses between archaeological artifacts and the inferences of the archaeologist and to reduce the routine work. Here, a dedicated database has been proposed, able to store the information extracted from huge quantities of archaeological material using a specific shape feature recognizer. This information is useful for making comparisons but also to improve the archaeological knowledge. The database has been implemented and used for the identification of pottery fragments and the reconstruction of archaeological vessels. Reconstruction, in particular, often requires the solution of complex problems, especially when it involves types of potsherds that cannot be treated with traditional methods.

3D Virtual Reconstruction of the Ancient Roman Incile of the Fucino Lake.

The construction of the artificial emissary of Fucino Lake is one of the most ambitious engineering buildings of antiquity. It was the longest tunnel ever made until the 19th century and, due to the depth of the adduction inlet, it required a monumental and complex incile, which, for functionality, cannot be compared to other ancient emissaries. The Roman emissary and its "incile" (Latin name of the inlet structure) were almost completely destroyed in the 19th century, when Fucino Lake was finally dried. Today, only few auxiliary structures such as wells, tunnels, and winzes remain of this ancient work. As evidence of the ancient incile remains a description made by those who also destroyed it and some drawings made by travelers who, on various occasions, visited the site. This paper presents a virtual reconstruction of the Roman incile, obtained both through the philological study of the known documentation, interpreting iconographic sources that represent the last evidence of this structure, and through the survey on the territory. The main purpose is to understand its technical functionalities, the original structures, and its evolution during the time, taking into account the evolution of the Fucino Lake water levels, technological issues, and finally offering its visual reconstruction.

A method for 3D detection of symmetry line in asymmetric postures.

The methods for symmetry line detection presented in the literature are typically suited to analyse symmetric upright postures, both standing and seated. The proposed method focuses on the symmetry line detection in subjects assuming asymmetric postures in which this line falls far outside the sagittal plane. The proposed approach evaluates the symmetry line by means of an autoregressive process in order to determine the set of planes suited to slice the back coherently with its geometric spatial configuration. The method is analysed assuming the cutaneous marking as reference and it is compared with a previous one, also developed by these authors. Results are analysed and critically discussed.