The chemicals between us-First results of the cluster analyses on anatomy embalming procedures in the German-speaking countries.

Hands-on courses utilizing preserved human tissues for educational training offer an important pathway to acquire basic anatomical knowledge. Owing to the reevaluation of formaldehyde limits by the European Commission, a joint approach was chosen by the German-speaking anatomies in Europe (Germany, Austria, Switzerland) to find commonalities among embalming protocols and infrastructure. A survey comprising 537 items was circulated to all anatomies in German-speaking Europe. Clusters were established for "ethanol"-, formaldehyde-based ("FA"), and "other" embalming procedures, depending on the chemicals considered the most relevant for each protocol. The logistical framework, volumes of chemicals, and infrastructure were found to be highly diverse between the groups and protocols. Formaldehyde quantities deployed per annum were three-fold higher in the "FA" (223 L/a) compared to the "ethanol" (71.0 L/a) group, but not for "other" (97.8 L/a), though the volumes injected per body were similar. "FA" was strongly related to table-borne air ventilation and total fixative volumes ≤1000 L. "Ethanol" was strongly related to total fixative volumes >1000 L, ceiling- and floor-borne air ventilation, and explosion-proof facilities. Air ventilation was found to be installed symmetrically in the mortuary and dissection facilities. Certain predictors exist for the interplay between the embalming used in a given infrastructure and technical measures. The here-established cluster analysis may serve as decision supportive tool when considering altering embalming protocols or establishing joint protocols between institutions, following a best practice approach to cater toward best-suited tissue characteristics for educational purposes, while simultaneously addressing future demands on exposure limits.

Extended reality visualization of medical museum specimens: Online presentation of conjoined twins curated by Dr. Jacob Henle between 1844-1852.

Background: The purpose of this study is to characterize a full-term conjoined twins' cadaver curated by Dr. Jacob Henle sometime between 1844 and 1852 and demonstrate digital distribution of an old and rare medical museum specimen using an extended reality (XR) model workflow. Methods: The cadaver (Preparation 296) is in the Department of Anatomy and Cell Biology at the University of Heidelberg. An XR display workflow comprises image capture, segmentation, and visualization using CT/MR scans derived from the cadaver. Online radiology presentation to medical students focuses on diagnostic characteristics of anatomical systems depicted with XR models. Results: Developmental defects in Preparation 296 include duplicated supradiaphragmatic structures and abnormal osteological features. Subdiaphragmatically, the gut is continuous on the right, but terminates at the distal esophagus on the left. One large liver occupies the abdomen with one spleen located on the left side. Observations suggest duplication of the primitive streak and separate notochords rostrally. Duplication occurs near the yolk sac and involves midgut formation while secondary midline fusion of the upper extremities and ribs likely results from the proximity of the embryos during development. Medical students access the model with device agnostic software during the curricular topic "Human Body Plan" that includes embryology concepts covering mechanisms of twinning. Conclusions: The workflow enables ease-of-access XR visualizations of an old and rare museum specimen. This study also demonstrates digital distribution and utilization of XR models applicable to embryology education.

Low-dose CBCT imaging of alveolar buccal bone adjacent to mandibular anterior teeth- a pilot study.

OBJECTIVES: Accurate description of buccal bone adjacent to mandibular anterior teeth is helpful for planning and monitoring periodontal and orthodontic treatment. Low-dose cone beam computed tomography (LD-CBCT) imaging has shown promising results for very small dental structures in animals. This study asserts that LD-CBCT is sufficiently accurate to measure buccal alveolar bone adjacent to human mandibular anterior teeth. MATERIALS AND METHODS: Buccal bone level adjacent to 16 mandibular anterior teeth from four human cadavers was measured radiographically using one high-dose (HD) CBCT protocol and two LD-CBCT protocols. The resulting radiographic measurements of buccal bone height (bl) and thickness (bt) were compared with reference probe and reflected-light microscopy measurements. Measurement medians and Bland-Altman plots were calculated, and a linear mixed model was used to compare raters and imaging modalities. RESULTS: All regression coefficients were approximately 0, indicating high interrater, intrarater, and intermodality agreement. No significant differences were found between reference measurements and CBCT protocols. The mean differences for bl measurements were 0.07 mm (rater 1 [r1]) and 0.12 mm (rater 2 [r2]) for HD-CBCT; 0.07 mm (r1) and 0.13 mm (r2) for LD-CBCT-1; and 0.02 mm (r1) and 0.01 mm (r2) for LD-CBCT-2. For bt measurements, mean differences were 0.02 mm (r1) and 0.02 mm (r2) for HD-CBCT; 0.01 mm (r1) and 0.01 mm (r2) for LD-CBCT-1; and 0.00 mm (r1) and 0.01 mm (r2) for LD-CBCT-2. CONCLUSIONS: Within the limitations of the present study, LD-CBCT seems to be a precise method for describing buccal bone and its thickness adjacent to mandibular anterior teeth in this experimental setting. CLINICAL RELEVANCE: For the first time, this study showed LD-CBCT produces excellent results and is a reliable modality for imaging buccal bone in vitro. If clinical studies confirm these results, LD-CBCT could enable better treatment planning and monitoring at a radiation dose that is far lower than that of conventional HD-CBCT but similar to that of panoramic views.

Strengths and Weaknesses of Non-enhanced and Contrast-enhanced Cadaver Computed Tomography Scans in the Teaching of Gross Anatomy in an Integrated Curriculum.

Cadaver-specific postmortem computed tomography (PMCT) has become an integral part in anatomy teaching at several universities. Recently, the feasibility of contrast-enhanced (CE)-PMCT has been demonstrated. The purpose of this study was to identify particular strengths and weaknesses of both non-enhanced and contrast-enhanced PMCT compared to conventional cadaver dissection. First, the students' perception of the learning effectiveness of the three different modalities have been assessed using a 34-item survey (five-point Likert scale) covering all anatomy course modules. Results were compared using the nonparametric Friedman Test. Second, the most frequent artifacts in cadaver CT scans, were systematically analyzed in 122 PMCT and 31 CE-PMCT data sets to quantify method-related limitations and characteristics. Perfusion quality was assessed in 57 vascular segments (38 arterial and 19 venous). The survey was answered by n = 257/320 (80.3%) students. Increased learning benefits of PMCT/ CE-PMCT compared to cadaver dissection were found in osteology (2/3 categories, P < 0.001), head and neck (2/5 categories, P < 0.01), and brain anatomy (3/3 categories, P < 0.01). Contrast-enhanced-PMCT was perceived particularly useful in learning vascular anatomy (10/10 categories, P < 0.01). Cadaver dissection received significantly higher scores compared to PMCT and CE-PMCT in all categories of the abdomen and thorax (7/7 categories, P < 0.001), as well as the majority of muscular anatomy (5/6 categories, P < 0.001). Frequent postmortem artifacts (total n = 28, native-phase n = 21, contrast injection-related n = 7) were identified and assessed. The results of this work contribute to the understanding of the value of integrating cadaver-specific PMCT in anatomy teaching.

Contrast-enhanced cadaver-specific computed tomography in gross anatomy teaching.

OBJECTIVES: To establish contrast-enhanced (CE) cadaver-specific post-mortem computed tomography (PMCT) in first-year gross anatomy teaching and quantitatively evaluate its learning benefit. METHODS: 132 first-year medical students were included in this IRB-approved study and randomly assigned to an intervention group (n=59) provided with continuous access to CE and non-enhanced (NE) cadaver-specific PMCT-scans during the first-semester gross anatomy course, and a control group (n=73) that had only NE cadaver-specific PMCT data available. Four multiple-choice tests were carried out (15 questions each) subsequent to completion of the corresponding anatomy module: Head and neck anatomy, extremities, thorax, and abdomen. Median test results were compared in each module between the groups using the Wilcoxon rank-sum test. Additionally, participants of the intervention group answered a 15-item feedback-questionnaire. RESULTS: The intervention group achieved significantly higher test scores in head and neck anatomy (median=12.0, IQR=10.0-13.0) versus the control group (median=10.5, IQR=9.0-12.0) (p<0.01). There were no significant differences in the comparison of other modules. CEPMCT was highly appreciated by undergraduate medical students. CONCLUSIONS: The incorporation of contrast-enhanced cadaver-specific PMCT-scans in gross anatomy teaching was proven to be feasible in the framework of the medical curriculum and significantly improved the students' learning performance in head and neck anatomy. KEY POINTS: • Cadaver-specific contrast-enhanced post-mortem CT (CEPMCT) is feasible in the medical curriculum. • CEPMCT yields significantly improved learning performance in head and neck anatomy (p<0.01). • CEPMCT is highly appreciated by medical students and used in tutor- or self-guided modes.

Cadaver-specific CT scans visualized at the dissection table combined with virtual dissection tables improve learning performance in general gross anatomy.

OBJECTIVES: The purpose of this study was to quantify the benefit of the incorporation of radiologic anatomy (RA), in terms of student training in RA seminars, cadaver CT scans and life-size virtual dissection tables on the learning success in general anatomy. METHODS: Three groups of a total of 238 students were compared in a multiple choice general anatomy exam during first-year gross anatomy: (1) a group (year 2015, n 1 = 50) that received training in radiologic image interpretation (RA seminar) and additional access to cadaver CT scans (CT + seminar group); (2) a group (2011, n 2 = 90) that was trained in the RA seminar only (RA seminar group); (3) a group (2011, n 3 = 98) without any radiologic image interpretation training (conventional anatomy group). Furthermore, the students' perception of the new curriculum was assessed qualitatively through a survey. RESULTS: The average test score of the CT + seminar group (21.8 ± 5.0) was significantly higher when compared to both the RA seminar group (18.3 ± 5.0) and the conventional anatomy group (17.1 ± 4.7) (p < 0.001). CONCLUSIONS: The incorporation of cadaver CT scans and life-size virtual dissection tables significantly improved the performance of medical students in general gross anatomy. Medical imaging and virtual dissection should therefore be considered to be part of the standard curriculum of gross anatomy. KEY POINTS: • Students provided with cadaver CT scans achieved 27 % higher scores in anatomy. • Radiological education integrated into gross anatomy is highly appreciated by medical students. • Simultaneous physical and virtual dissection provide unique conditions to study anatomy.

Single-Incision Mini-Slings: Obturator Complex Pull-Out-Force Measurements.

AIM: To evaluate the different pull-out-force out of the obturator membrane and the obturator internus muscle of 2 mini-sling systems for stress urinary incontinence (SUI) treatment. MATERIAL AND METHODS: In a prospective study, the pull-out-force measurements were performed on 8 female cadaver pelvises, both on the obturator membrane and internal muscle, using the force measurement device PCE-FM50 (PCE Instruments). Tested were the hooks of 2 on the market available mini-sling kits (MiniArc by American Medical System; Ajust by BARD Inc.). Connected to the force measurement device, the hooks were placed into the obturator membrane and the obturator internus muscle. Mean value and SD were documented. RESULTS: On the complete obturator complex, Ajust showed a significantly higher pull-out-force (2,561.75 ± 638.8 g) than did the MiniArc (1,780.69 ± 442.3 g), p = 0.025. No significant differences were performed on the obturator membrane. CONCLUSIONS: The Ajust mini-sling hook is, given the objective results, more stably attached to the obturator complex than the MiniArc. Yet, both systems are sufficiently attachable to the evaluated anatomic structures, fulfilling the needed requirements for their use in the treatment of SUI.

Intraosseous vascular access through the anterior mandible--a cadaver model pilot study.

BACKGROUND: Several insertion sites have been described for intraosseous puncture in cases of emergencies when a conventional vascular access cannot be established. This pilot study has been designed to evaluate the feasibility of the mandibular bone for the use of an intraosseous vascular access in a cadaver model. METHODOLOGY/PRINCIPAL FINDINGS: 17 dentistry and 16 medical students participating in a voluntary course received a short introduction into the method and subsequently used the battery powered EZ-IO system with a 15 mm cannula for a puncture of the anterior mandible in 33 cadavers. The time needed to perform each procedure was evaluated. India ink was injected into the accesses and during the anatomy course cadavers were dissected to retrace the success or failure of the puncture. Dental students needed 25.5±18.9(mean±standard deviation)s and medical students 33±20.4 s for the procedure (p = 0.18). Floor of mouth extravasation occurred in both groups in 3 cases. Success rates were 82 and 75% (p = 0.93). CONCLUSIONS/SIGNIFICANCE: Despite floor of mouth extravasation of injected fluid into a mandibular intraosseous access might severely complicate this procedure, the anterior mandible may be helpful as an alternative to other intraosseous and intravenous insertion sites when these are not available in medical emergencies.

Evaluation of the sternal intraosseous route as alternative emergency vascular access for the dental office: a manikin and cadaver model pilot study.

OBJECTIVE: To evaluate 2 sternal intraosseous access devices as alternatives to emergency intravenous access for dentists, using a manikin and a cadaver model. STUDY DESIGN: A group of 37 students performed a sternal intraosseous access on a manikin using a Vidacare kit including a puncture template and a prepuncture skin incision. Five months later, 9 of the students used the Vidacare and 8 used an Illinois needle (without template and incision) on adult human cadavers. India ink was injected as a tracer. RESULTS: Shorter times were recorded on cadavers compared with manikins in both systems. One Vidacare puncture ended subcutaneously. Two Illinois needle punctures perforated the sternum, one with intense mediastinal ink traces. Vidacare punctures took longer compared with Illinois needle punctures (medians, 32 vs 12 seconds; P = .0002). CONCLUSIONS: Template use to identify the sternal puncture position, combined with additional prepuncture skin incision, may be more efficient and less predisposed to severe complications for dentists' emergency use.

Isolation of Acinetobacter baumannii complex and methicillin-resistant Staphylococcus aureus from hospital rooms following terminal cleaning and disinfection: can we do better?

OBJECTIVE: To study the frequency of isolation of Acinetobacter baumannii complex (ABC) and methicillin-resistant Staphylococcus aureus (MRSA) from surfaces of rooms newly vacated by patients with multidrug-resistant (MDR) ABC following various rounds of routine terminal cleaning and disinfection (C/D) with bleach or 1 round of C/D followed by hydrogen peroxide vapor (HPV) treatment. SETTING: A 900-bed tertiary care hospital. METHODS: ABC and MRSA cultures were obtained from hospital rooms including 312 rooms (mean, 18.3 sites/room) following 4 rounds of C/D, 37 rooms (mean, 20 sites/room) following 1 round of C/D before and after HPV treatment, and 134 rooms (mean, 20 sites/room) following 1 round of C/D and HPV treatment. RESULTS: Following 4 rounds of C/D, 83 (26.6%) rooms had 1 or more culture-positive sites; 102 (1.8%) sites in 51 (16.4%) rooms grew ABC, and 108 (1.9%) sites in 44 (14.1%) rooms grew MRSA. The addition of HPV treatment to 1 round of C/D resulted in a significant drop in ABC- and MRSA-positive room sites (odds ratio, 0 [95% confidence interval, 0-0.8]; P = .04 for both organisms). Following 1 round of C/D and HPV treatment, 6 (4.5%) rooms were culture-positive for ABC, MRSA, or both. CONCLUSIONS: Routine terminal C/D of hospital rooms vacated by MDRABC-positive patients may be associated with a significant number of ABC- or MRSA-positive room surfaces even when up to 4 rounds of C/D are performed. The addition of HPV treatment to 1 round of C/D appears effective in reducing the number of persistently contaminated room sites in this setting.

Integrated teaching of anatomy and radiology using three-dimensional image post-processing.

This article presents a new way of teaching by integrating both anatomy and radiology using three-dimensional image post-processing tools. One preclinical and one clinical module were developed for integrated teaching of anatomy and radiology. Potential benefits were assessed by anonymous evaluation among the 176 participating students. The students highly appreciated the new approach, especially the high degree of interactivity with the post-processing software and the possibility to correlate the real dissection with the virtual dissection. Students agreed that three-dimensional imaging and postprocessing improved their understanding of difficult anatomical topics and topographical relations. We consider the new approach to provide great additional benefits for participating students regarding preparation for everyday clinical practice. In particular, it imparts familiarity with imaging and image post-processing techniques and may improve anatomical understanding, radiological diagnostic skills and three-dimensional appreciation.

Comparison of two intraosseous infusion systems for adult emergency medical use.

INTRODUCTION: The current guidelines of the European Resuscitation Council (ERC) stipulate that an intraosseous access should be placed if establishing a peripheral venous access for cardiopulmonary resuscitation (CPR) would involve delays. The aim of this study was therefore to compare a manual intraosseous infusion technique (MAN-IO) and a semi-automatic intraosseous infusion system (EZ-IO) using adult human cadavers as a model. MATERIALS AND METHODS: After receiving verbal instruction and giving their written informed consent, the participants of the study were randomized into two groups (group I: MAN-IO, and group II: EZ-IO). In addition to the demographic data, the following were evaluated: (1) Number of attempts required to successfully place the infusion, (2) Insertion time, (3) Occurrence of technical complications and (4) User friendliness. RESULTS: Evaluation protocols from 84 study participants could be evaluated (MAN-IO: n=39 vs. EZ-IO: n=45). No significant differences were seen in the study participants' characteristics. Insertion times (MW+/-S.D.) of the respective successful attempts were comparable (MAN-IO: 33+/-28s vs. EZ-IO: 32+/-11s). When using the EZ-IO, the access was successfully established significantly more often on the first attempt (MAN-IO: 79.5% vs. EZ-IO: 97.8%; p<0.01). The EZ-IO was also found to have more advantages in terms of technical complications (MAN-IO: 15.4% vs. EZ-IO: 0.0%; p<0.01) and user friendliness (school grading system: MAN-IO: 1.9+/-0.7 vs. EZ-IO: 1.2+/-0.4; p<0.01). CONCLUSIONS: In an adult human cadaver model, the semi-automatic system was proven to be more effective. The EZ-IO gave more successful results, was associated with fewer technical complications, and is user friendlier.

An overview of FDA medical device regulation as it relates to deep brain stimulation devices.

The United States Food and Drug Administration (FDA) is charged with assuring the safety and effectiveness of a variety of medical products and the FDA's Center for Devices and Radiological Health is responsible for premarket and postmarket regulation of medical devices. In this paper, we review--from device classification and clinical studies to the final marketing application--FDA's premarket requirements and postmarket requirements as they relate to deep brain stimulation devices.

Macroscopic and microangiographic anatomy of the teres major muscle: a new free functional muscle flap?

BACKGROUND: The teres major can be seen as an additional head of the latissimus dorsi muscle for three-dimensional movement of the arm. It gained importance in pedicled muscle transfers for the treatment of plexus palsies and shoulder instability. Its supplying vessels belong to the subscapular system. According to the literature, the muscle was transferred only once as a free microvascular but nonfunctional graft. METHODS: Eleven flaps from fresh cadavers were dissected and perfused with radiopaque media. The detailed macroscopic and microangiographic anatomy was investigated to determine its potential use as a free functional muscle flap. RESULTS: Three different access routes are possible. The mean length of the flap was 158 mm, and the distal and proximal tendinous widths were 24 mm and 52 mm, respectively. A Taylor type 1 nerve and Mathes type 2 vessel distribution was found in all specimens. The main pedicle is situated in the middle third of the superomedial border of the flap and derives almost exclusively from the circumflex scapular artery. Radioangiograms indicate possible splitting of the muscle in the transverse and longitudinal directions. The nerve could always be isolated to a considerable length (66 mm) before reaching the posterior cord. CONCLUSIONS: This anatomical study indicates that the teres major can be seen as a separate entity in the subscapular system and can be transferred as a free flap either alone or in combination. According to what is known from pedicled transfers, the donor-site morbidity should be low if the latissimus dorsi is left intact.

Maturation of executive function in autism.

BACKGROUND: Executive dysfunction has been reported at different ages in autism. It is not clear however, when this impairment emerges or how its expression is affected by development. METHODS: 61 non-mentally retarded autism participants (AUT) and 61 age, gender, and IQ matched typically developing participants (CON) were assessed with two oculomotor executive function tasks, the oculomotor delayed response task (ODR) and the antisaccade task (AS), as well as a visually-guided saccade sensorimotor task (VGS). RESULTS: The AUT group demonstrated impairments in response inhibition and spatial working memory at all ages tested. Developmental improvements in speed of sensorimotor processing and voluntary response inhibition were similar in both groups indicating sparing of some attentional control of behavior. Developmental progression in the speed of initiating a cognitive plan and maintaining information on line over time, however, was impaired in the AUT group indicating abnormal development of working memory. CONCLUSIONS: These results indicate that while executive dysfunction is present throughout development, there is evidence for both typical and atypical developmental progression of executive functions in autism. The plasticity suggested by the developmental improvements may have implications regarding appropriate developmental epochs and types of interventions aimed at enhancing cognitive capacities in individuals with autism.

Prenatal growth of the interorbital septum in Macaca mulatta.

The interorbital septum is the portion of the anterior cranial base directly contiguous with the eyes. It is considered to be a primitive trait that has evolved independently in various primate groups as a result of ocular and olfactory convergence with concomitant encephalization. This process is hypothesized to have reduced the size of the lateral nasal capsule exposing the anterior cranial base to the ocular apparatus and thus creating an interorbital septum. The purpose of this study was to determine whether differential growth trajectories occur among the chondrocranial elements corresponding to this hypothesis. Macaca mulatta embryos from the Zingeser Collection were selected for this analysis since this primate shows a well-developed interorbital septum throughout ontogeny. Embryos between 40 and 90 days of gestation were selected from the collection and coronal sections including the eye, anterior cranial base and lateral nasal capsule were subjected to video microscopy and computerized reconstruction using SURFdriver Software. Tissue volumes were computed for these tissues while chondrocytic growth attributes were measured utilizing stereological techniques. Results showed a strong correlation between the volume of the lateral nasal capsule and anterior cranial base and these two structures showed a consistent correlation with an increasing eye volume. Chondrocytic volume density and average diameter were larger in the lateral nasal capsule while shape, numerical density and average volume did not differ between the two tissues. These data suggest if differential growth does account for a reduction of the nasal capsule compared to the central cranial base stem, it does not appear to result from differential tissue size change. However, certain cellular growth activities leading to premature chondrocytic hypertrophy may be involved.