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11.

Purpose

To test the face and content validity of 3D virtual-rendered printed models used before robot-assisted prostate cancer and nephron-sparing surgery.

Methods

Patients who underwent live surgery during an international urological meeting organized in January 2017 were enrolled. Those with organ-confined prostate cancer underwent robot-assisted radical prostatectomy. Patients with a single renal tumor underwent minimally invasive nephron-sparing surgery. High-resolution (HR) imaging was obtained for all patients. Those with kidney tumors received contrast-enhanced CT scan with angiography; those with prostate cancer underwent mp-MRI. Images in DICOM format were processed by dedicated software. The first step was the rendering of a 3D virtual model. The models were then printed. They were presented during the live surgery of the urological meeting. All the participants and the operated patients were asked to fill a questionnaire about their opinion expressed in Likert scale (1–10) about the use and application of the 3D printed models.

Results

18 patients were enrolled, including 8 undergoing robot-assisted radical prostatectomy and 10 undergoing minimally invasive partial nephrectomy. For each patient, a virtual 3D printed model was created. The attendants rated the utility of printed models in surgical planning, anatomical representation and the role of technology in surgical training as 8/10, 10/10 and 9/10, respectively. All patients reported favorable feedbacks (from 9 to 10/10) about the use of the technology during the case discussion with the surgeon.

Conclusions

In our experience, 3D printing technology has been perceived as a useful tool for the purpose of surgical planning, physician education/training and patient counseling. Further researches are expected to increase the level of evidence.
  相似文献   
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13.

Purpose

This investigation aimed to examine the extent to which case-based discussion with experts could influence the audience’s opinions on the treatment of patients during a continuing medical education event for spine surgeons.

Methods

We conducted a prospective controlled crossover study of 90 surgeons. During a continuing medical education activity using case-based discussion, quiz questions were used which asked participants (attendants and faculty group) their opinions on the best choices about diagnosis and treatment in a number of cases. No answer was considered correct, but we evaluated the number of participants choosing each specific answer among a number of valid options. Quiz questions were collected with an automated response system at the entry and at the end of each case discussion. Change in participant’s opinions was estimated from the change in the preferred answers between the entry and exit quizzes. Chi-square analysis was performed to determine significance.

Results

Sixty-two attendants out of eighty three (75%) and six faculties out of twelve (50%) responded to the survey. After the case discussion, 68.2% (p < 0.04, Chi-square test) of the attendants changed their opinion on the appropriate treatment. The faculty answers, however, showed no significant change in opinions regarding the identification of the appropriate treatment.

Conclusions

On the basis of our results, case-based discussion driven by experts, as a form of teaching, has a measurable effect in terms of changes in the learners’ opinions.
  相似文献   
14.

Objective

The aim of the study was to provide, by means of computational fluid dynamics, a comparative analysis after carotid endarterectomy (CEA) between patch graft (PG) and primary closure (PC) techniques performed in real carotid geometries to identify disturbed flow conditions potentially involved in the development of restenosis.

Methods

Eight carotid geometries in seven asymptomatic patients who underwent CEA were analyzed. In six cases (A-F), CEA was performed using PG closure; in two cases (G and H), PC was performed. Three-dimensional carotid geometries, derived from postoperative magnetic resonance angiography, were reconstructed, and a computational fluid dynamics analysis was performed. A virtual scenario with PC closure was designed in patients in whom PG was originally inserted and vice versa. This allowed us to compare for each patient hemodynamic effects in the PG and PC scenarios in terms of oscillatory shear index (OSI) and relative residence time (RRT), considered indicators of disturbed flow.

Results

For the six original PG cases, the mean averaged-in-space OSI was 0.07 ± 0.01 for PG and 0.03 ± 0.02 for virtual-PC (difference, 0.04 ± 0.01; P = .0016). The mean of the percentage of area (%A) with OSI >0.2 resulted in 10.08% ± 3.38% for PG and 3.80% ± 3.22% for virtual-PC (difference, 6.28 ± 1.91; P = .008). For the same cases, the mean of the averaged-in-space RRT resulted in 5.48 ± 3.40 1/Pa for PG and 2.62 ± 1.12 1/Pa for virtual-PC (difference, 2.87 ± 1.46; P = .097). The mean of %A RRT >4.0 1/Pa resulted in 26.53% ± 12.98% for PG and 9.95% ± 6.53% for virtual-PC (difference, 16.58 ± 5.93; P = .025). For the two original PC cases, the averaged-in-space OSIs were 0.02 and 0.04 for PC and 0.03 and 0.02 for virtual-PG; the %A OSIs >0.2 were 0.9% and 7.6% for PC and 3.0% and 2.2% for virtual-PG; the averaged-in-space RRTs were 1.8 and 2.0 1/Pa for PC and 2.9 and 1.9 1/Pa for virtual-PG; the %A RRTs >4.0 1/Pa were 6.8% and 9.8% for PC and 9.4% and 6.2% for virtual-PG. These results revealed generally higher disturbed flows in the PG configurations with respect to the PC ones.

Conclusions

OSI and RRT values were generally higher in PG cases with respect to PC, especially for high carotids or when the arteriotomy is mainly at the bulb region. Thus, an elective use of patch should be considered to prevent disturbed flows.  相似文献   
15.
16.
A subset of familial and sporadic clear cell renal cell carcinomas (ccRCCs) is believed to develop from cystic precursor lesions. Loss of function of the von Hippel-Lindau tumor suppressor gene (VHL) predisposes renal epithelial cells to loss of the primary cilium in response to specific signals. Because the primary cilium suppresses renal cyst formation, loss of the cilium may be an initiating event in the formation of ccRCC. To test this hypothesis, we analyzed the consequences of inducible renal epithelium–specific deletion of Vhl together with ablation of the primary cilium via deletion of the kinesin family member 3A (Kif3a) gene. We developed a microcomputed tomography–based imaging approach to allow quantitative longitudinal monitoring of cystic burden, revealing that combined loss of Vhl and Kif3a shortened the latency of cyst initiation, increased the number of cysts per kidney, and increased the total cystic burden. In contrast with findings in other cystic models, cysts in Kif3a mutant mice did not display accumulation of hypoxia-inducible factor 1-α (HIF1α), and deletion of both Hif1a and Kif3a did not affect cyst development or progression. Vhl/Kif3a double mutation also increased the frequency of cysts that displayed multilayered epithelial growth, which correlated with an increased frequency of misoriented cystic epithelial cell divisions. These results argue against the involvement of HIF1α in promoting renal cyst growth and suggest that the formation of simple and atypical renal cysts that resemble ccRCC precursor lesions is greatly accelerated by the combined loss of Vhl and the primary cilium.  相似文献   
17.

Background

Proximal inter-phalangeal (PIP) joint arthrodesis today represents the standard treatment for structured hammertoes; however, recently, a lot of new intramedullary devices for the fixation of this arthrodesis have been introduced. The purpose of this work is to look at the currently available devices and to perform a review of the present literature.

Materials and methods

A literature search of PubMed/Medline and Google Scholar databases, considering works published up until September 2014 and using the keywords: hammertoe, arthrodesis, PIP joint, fusion, intramedullary devices, and K-wire, was performed. The published papers were included in the present study only if they met the following inclusion criteria: English articles, arthrodesis of PIP joints for hammertoes with new generation intramedullary devices, series with n > 10. Studies using absorbable pins or screws that are considered as another kind of fixation that involved more than one articulation, as well as comments, letters to the editor, or newsletters were excluded.

Results

Nine publications were included. Of the patients’ reports, 93–100 % were good or excellent concerning satisfaction. Radiological arthrodesis was achieved in 60.5–100 % of cases. Three of the publications compared the new devices with the K-wire. Of these three articles, two employed the traditional technique and one the buried technique. The AOFAS score, evaluated in three publications, showed a delta of 19, 45 and 58 points. Major complications, which required a secondary surgical revision, were between 0 and 8.6 %. The complications of the K-wire and the new devices were similar; also the reoperation rate was close to equal (maximal difference 2 %). On the other hand, these kinds of devices definitely have a higher price, compared to the K-wire.

Conclusion

The use of these new devices provides good results; however, their high price is currently a problem. For this reason, cost-benefit studies seem to be necessary to justify their use as standard treatment.

Level of evidence

Level III systematic review.  相似文献   
18.
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20.
Parasitology Research - Free-living amoebae of the genus Acanthamoeba are potentially pathogenic protozoa widespread in the environment. The detection/diagnosis as well as environmental survey...  相似文献   
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