Biomedical subjects

Juan Cendan

Publications and source records attributed to Juan Cendan.

5 recordsLinked to original sources

PubMed2006

Developing a multimedia environment for customized teaching of an adrenalectomy.

We have developed a computer based simulation process which allows a surgical expert to create a customized operative environment. This virtual environment, the Toolkit for Illustration of Procedures in Surgery (3D TIPS), is deployed on a low-cost computer system and requires minimal training for the programmer. The learner can be engaged in training immediately and the educator can modify the system and annotate the procedure to highlight specific points using video clips, operative images, and the like. A laparoscopic adrenalectomy is presented as a proof of concept in the accompanying article.

Adrenalectomy↗

PubMed2006

The use of virtual patients to teach medical students history taking and communication skills.

BACKGROUND: At most institutions, medical students learn communication skills through the use of standardized patients (SPs), but SPs are time and resource expensive. Virtual patients (VPs) may offer several advantages over SPs, but little data exist regarding the use of VPs in teaching communication skills. Therefore, we report our initial efforts to create an interactive virtual clinical scenario of a patient with acute abdominal pain to teach medical students history-taking and communication skills. METHODS: In the virtual scenario, a life-sized VP is projected on the wall of an examination room. Before the virtual encounter, the student reviews patient information on a handheld tablet personal computer, and they are directed to take a history and develop a differential diagnosis. The virtual system includes 2 networked personal computers (PCs), 1 data projector, 2 USB2 Web cameras to track the user's head and hand movement, a tablet PC, and a microphone. The VP is programmed with specific answers and gestures in response to questions asked by students. The VP responses to student questions were developed by reviewing videotapes of students' performances with real SPs. After obtaining informed consent, 20 students underwent voice recognition training followed by a videotaped VP encounter. Immediately after the virtual scenario, students completed a technology and SP questionnaire (Maastricht Simulated Patient Assessment). RESULTS: All participants had prior experience with real SPs. Initially, the VP correctly recognized approximately 60% of the student's questions, and improving the script depth and variability of the VP responses enhanced most incorrect voice recognition. Student comments were favorable particularly related to feedback provided by the virtual instructor. The overall student rating of the virtual experience was 6.47 +/- 1.63 (1 = lowest, 10 = highest) for version 1.0 and 7.22 +/- 1.76 for version 2.0 (4 months later) reflecting enhanced voice recognition and other technological improvements. These overall ratings compare favorably to a 7.47 +/- 1.16 student rating for real SPs. CONCLUSIONS: Despite current technological limitations, virtual clinical scenarios could provide students a controllable, secure, and safe learning environment with the opportunity for extensive repetitive practice with feedback without consequence to a real or SP.

Clinical Competence↗

PubMed2006

Exploiting graphics hardware for haptic authoring.

Real-time, plausible visual and haptic feedback of deformable objects without shape artifacts is important in surgical simulation environments to avoid distracting the user. We propose to leverage highly parallel stream processing, available on the newest generation graphics cards, to increase the level of both visual and haptic fidelity. We implemented this as part of the University of Florida's haptic surgical authoring kit.

Computer Graphics↗

PubMed2002

Sequential dermal-peritumoral radiocolloid injection for sentinel node biopsy for breast cancer: the University of Florida experience.

Although sentinel lymph node (SLN) biopsy is rapidly becoming the standard of care for small breast cancers the optimal radiocolloid injection technique remains controversial. We report our experience with sequential dermal-peritumoral radiocolloid injection that takes advantage of both techniques. One hundred eighteen patients with clinical stage T(is), T1, T2 and N0 breast cancer underwent SLN biopsy at the University of Florida. Twelve to 18 hours before surgery patients received either an injection of 0.5 to 1.0 mCi 50:50 filtered:unfiltered technetium sulfur colloid into the dermis overlying the tumor and/or a peritumoral injection of a 3 to 4-mCi of radiocolloid 30 minutes later. Dynamic lymphoscintigraphy was performed and the topographical location of all imaged lymph nodes was marked on the skin. The next morning the surgeon utilized a hand-held gamma probe to remove all SLN(s) defined as any lymph node with radioactive counts 10 per cent or more of the ex vivo counts of the most radioactive SLN [internal mammary (IM) nodes were not removed]. The SLN identification rate was 98.5 per cent (3 IM nodes) for dermal injection (d.), 83.3 per cent (1 IM node) for peritumoral injection (p.), and 100 per cent (14 IM nodes) for sequential dermal-peritumoral injection (d.p.) (p < 0.05 DP versus D). Sequential d.p. 50:50 filtered:unfiltered technetium sulfur colloid injection results in a rapid, high SLN identification rate that persists until surgery the next morning. Delineation of nonaxillary SLNs may lead to more accurate breast cancer staging and may also influence the delivery of IM node radiation.

Aged↗

PubMedDate not supplied

Sentinel lymph node biopsy for ductal carcinoma in situ: an evolving approach at the University of Florida.

While sentinel lymph node biopsy (SLNB) has virtually replaced axillary dissection as the initial diagnostic procedure for invasive breast cancer, the role of SLNB in ductal carcinoma in situ (DCIS) remains controversial. The purpose of this study was to review our experience with SLNB in DCIS. All patients with DCIS or DCIS with microinvasion (DCISM) who underwent SLNB from June 1997 to April 2002 at the University of Florida were included for analysis. The indications for SLNB were at the discretion of the treating surgeon. Lymphatic mapping involved a sequential dermal-peritumoral radiocolloid injection and dynamic lymphoscintigraphy followed by an intraoperative assessment of radioactivity with a handheld gamma probe. All sentinel lymph nodes (SLNs) with radioactive counts>or=10% of the ex vivo counts of the most radioactive SLN were removed. Pathologic analysis consisted of slicing the SLN at 2 mm intervals for permanent section. All paraffin blocks of the SLNs were step sectioned in 4 microm sections (92 microm spacing) through the entire lymph node. Slides were then stained with an immunohistochemical stain for cytokeratin (AE1/AE3) and evaluated by microscopy. Nodal metastases were classified using the 6th edition of the American Joint Committee on Cancer (AJCC) staging manual. From April 1998 to April 2002, 43 patients with DCIS underwent SLNB at the University of Florida. Seven patients (16%) with multifocal or extensive DCIS (five patients) or DCISM (two patients) who underwent SLNB had a positive sentinel node. Two of the three patients considered positive by immunohistochemistry alone had either DCISM or invasive disease. Four (80%) of the five patients with extensive DCIS and a positive sentinel node were ultimately determined to have invasive or microinvasive disease. While SLNB remains controversial in DCIS, our data suggest that patients with extensive DCIS should undergo SLNB at the initial procedure to avoid the need for a second operation. Data from clinical trials are needed to determine the impact of SLNB results on overall survival in patients with DCIS.

Breast Neoplasms↗