Ann Zumwalt

Incorporating radiology into medical gross anatomy: Does the use of cadaver CT scans improve students' academic performance in anatomy?

Radiological images show anatomical structures in multiple planes and may be effective for teaching anatomical spatial relationships, something that students often find difficult to master. This study tests the hypotheses that (1) the use of cadaveric computed tomography (CT) scans in the anatomy laboratory is positively associated with performance in the gross anatomy course and (2) dissection of the CT‐scanned cadaver is positively associated with performance on this course. One hundred and seventy‐nine first‐year medical students enrolled in gross anatomy at Boston University School of Medicine were provided with CT scans of four cadavers, and students were given the opportunity to choose whether or not to use these images. The hypotheses were tested using logistic regression analysis adjusting for student demographic characteristics. Students who used the CT scans were more likely to score greater than 90% as an average practical examination score (odds ratio OR 3.6; 95% CI 1.4, 9.2), final course grade (OR 2.6; 95% CI 1.01, 6.8), and on spatial anatomy examination questions (OR 2.4; 95% CI 1.03, 5.6) than were students who did not use the CT scans. There were no differences in performance between students who dissected the scanned cadavers and those who dissected a different cadaver. These results demonstrate that the use of CT scans in medical gross anatomy is predictive of performance in the course and on questions requiring knowledge of anatomical spatial relationships, but it is not necessary to scan the actual cadaver dissected by each student. Anat Sci Educ 3: 56–63, 2010.

Evaluating Swallowing Muscles Essential for Hyolaryngeal Elevation by Using Muscle Functional Magnetic Resonance Imaging

PURPOSE Reduced hyolaryngeal elevation, a critical event in swallowing, is associated with radiation therapy. Two muscle groups that suspend the hyoid, larynx, and pharynx have been proposed to elevate the hyolaryngeal complex: the suprahyoid and longitudinal pharyngeal muscles. Thought to assist both groups is the thyrohyoid, a muscle intrinsic to the hyolaryngeal complex. Intensity modulated radiation therapy guidelines designed to preserve structures important to swallowing currently exclude the suprahyoid and thyrohyoid muscles. This study used muscle functional magnetic resonance imaging (mfMRI) in normal healthy adults to determine whether both muscle groups are active in swallowing and to test therapeutic exercises thought to be specific to hyolaryngeal elevation. METHODS AND MATERIALS mfMRI data were acquired from 11 healthy subjects before and after normal swallowing and after swallowing exercise regimens (the Mendelsohn maneuver and effortful pitch glide). Whole-muscle transverse relaxation time (T2 signal, measured in milliseconds) profiles of 7 test muscles were used to evaluate the physiologic response of each muscle to each condition. Changes in effect size (using the Cohen d measure) of whole-muscle T2 profiles were used to determine which muscles underlie swallowing and swallowing exercises. RESULTS Post-swallowing effect size changes (where a d value of >0.20 indicates significant activity during swallowing) for the T2 signal profile of the thyrohyoid was a d value of 0.09; a d value of 0.40 for the mylohyoid, 0.80 for the geniohyoid, 0.04 for the anterior digastric, and 0.25 for the posterior digastric-stylohyoid in the suprahyoid muscle group; and d values of 0.47 for the palatopharyngeus and 0.28 for the stylopharyngeus muscles in the longitudinal pharyngeal muscle group. The Mendelsohn maneuver and effortful pitch glide swallowing exercises showed significant effect size changes for all muscles tested, except for the thyrohyoid. CONCLUSIONS Muscles of both the suprahyoid and the longitudinal pharyngeal muscle groups are active in swallowing, and both swallowing exercises effectively target muscles elevating the hyolaryngeal complex. mfMRI is useful in testing swallowing muscle function.

Association between patella alta and the prevalence and worsening of structural features of patellofemoral joint osteoarthritis: the multicenter osteoarthritis study.

To examine the relationship between patella alta and the prevalence and worsening at followup of structural features of patellofemoral joint (PFJ) osteoarthritis (OA) on magnetic resonance imaging (MRI).

Association between measures of trochlear morphology and structural features of patellofemoral joint osteoarthritis on MRI: the MOST study.

The sulcus angle has been widely used in the literature as a measure of trochlear morphology. Recently, lateral trochlear inclination and trochlear angle have been reported as alternatives. The purpose of this study was to determine the association between measures of trochlear morphology and patellofemoral joint (PFJ) cartilage damage and bone marrow lesions (BMLs). Nine hundred seven knees were selected from the Multicenter Osteoarthritis Study, a cohort study of persons aged 50–79 years with or at risk for knee OA. Trochlear morphology was measured using lateral trochlear inclination, trochlear angle, and sulcus angle on axial MRI images; cartilage damage and BMLs were graded on MRI. We determined the association between quartiles of each trochlear morphology variable with the presence or absence of cartilage damage and BMLs in the PFJ using logistic regression. The strongest associations were seen with lateral trochlear inclination and lateral PFJ cartilage damage and BMLs, with knees in the lowest quartile (flattened lateral trochlea) having more than two times the odds of lateral cartilage damage and BMLs compared to those in the highest quartile (p < 0.0001). Lateral trochlear inclination may be the best method for assessment of trochlear morphology as it was strongly association with structural damage in the PFJ.

Quadriceps weakness, patella alta, and structural features of patellofemoral osteoarthritis.

To determine the relationship between quadriceps weakness and cartilage damage and bone marrow lesions (BMLs) in the patellofemoral joint (PFJ) and if this relationship is modified by patella alta.

Making Education Effective and Fun: Stations-Based Approach to Teaching Radiology and Anatomy to Third-Year Medical Students

RATIONALE AND OBJECTIVES A hands-on stations-based approach to teaching anatomy to third-year medical students is used at Boston University. The goal of our study was to demonstrate that such an interactive, team-based approach to teaching anatomy would be well received and be helpful in recall, comprehension, and reinforcement of anatomy learned in the first year of medical school. MATERIALS AND METHODS Each radiology-anatomy correlation lab was focused on one particular anatomic part, such as skull base, pelvis, coronary anatomy, etc. Four stations, including a three-dimensional model, computer, ultrasound, and posters, were created for each lab. Informed consent was obtained before online survey dissemination to assess the effectiveness and quality of radiology-anatomy correlation lab. This study was approved by our institutional institutional review board, and data were analyzed using a χ(2) test. RESULTS Survey data were collected from February 2010 through March 2012. The response rate was 33.5%. Overall, the highest percentage of students (46%) found the three-dimensional model station to be the most valuable. The computer station was most helpful in recall of the anatomic principles from the first year of medical school. Regarding the quality of the anatomy lab, less than 2% of the students thought that the images were of poor quality or the material presented was not clinically relevant. DISCUSSION Our results indicate that an interactive, team-based approach to teaching anatomy was well received by the medical students. It was engaging and students were able to benefit from it in multiple ways.

Radiologic EducationMaking Education Effective and Fun: Stations-Based Approach to Teaching Radiology and Anatomy to Third-Year Medical Students

RATIONALE AND OBJECTIVES A hands-on stations-based approach to teaching anatomy to third-year medical students is used at Boston University. The goal of our study was to demonstrate that such an interactive, team-based approach to teaching anatomy would be well received and be helpful in recall, comprehension, and reinforcement of anatomy learned in the first year of medical school. MATERIALS AND METHODS Each radiology-anatomy correlation lab was focused on one particular anatomic part, such as skull base, pelvis, coronary anatomy, etc. Four stations, including a three-dimensional model, computer, ultrasound, and posters, were created for each lab. Informed consent was obtained before online survey dissemination to assess the effectiveness and quality of radiology-anatomy correlation lab. This study was approved by our institutional institutional review board, and data were analyzed using a χ(2) test. RESULTS Survey data were collected from February 2010 through March 2012. The response rate was 33.5%. Overall, the highest percentage of students (46%) found the three-dimensional model station to be the most valuable. The computer station was most helpful in recall of the anatomic principles from the first year of medical school. Regarding the quality of the anatomy lab, less than 2% of the students thought that the images were of poor quality or the material presented was not clinically relevant. DISCUSSION Our results indicate that an interactive, team-based approach to teaching anatomy was well received by the medical students. It was engaging and students were able to benefit from it in multiple ways.

Gaze Patterns of Gross Anatomy Students Change with Classroom Learning.

Numerous studies have documented that experts exhibit more efficient gaze patterns than those of less experienced individuals. In visual search tasks, experts use fewer, longer fixations to fixate for relatively longer on salient regions of the visual field while less experienced observers spend more time examining nonsalient regions. This study investigates whether changes in gaze patterns reflect learning by students in a medical gross anatomy course. Students were asked to examine photographs of dissections similar to those they experienced in class and to identify the tagged structure in each image. We postulated that, compared to naive behavior (behavior at baseline and when examining unfamiliar content) students would examine familiar content for longer and would direct proportionally more fixation time on cognitively salient regions of the images while using fewer, longer duration fixations. Our students examined familiar images for significantly longer than they did at baseline (P < 0.0001) or for unfamiliar images (P < 0.0001). They also spent significantly longer examining cognitively salient regions of familiar images, as compared to examining those regions at baseline (P < 0.0001) and on unfamiliar images (P < 0.0001). However, these gaze patterns were characterized by more numerous fixations rather than fewer, longer fixations. These individuals are successful learners in a challenging gross anatomy course, but are not experts in anatomy. Therefore we speculate that the gaze pattern they exhibit characterizes an earlier stage of the learning process than has previously been documented in studies of expertise, which have primarily focused on the gaze patterns of true experts. Anat Sci Educ 8: 230–241.

Visualising hyolaryngeal mechanics in swallowing using dynamic MRI

In this study, coordinates of anatomical landmarks were captured using dynamic MRI (dMRI) to explore whether a proposed two-sling mechanism underlies hyolaryngeal elevation in pharyngeal swallowing. A principal component analysis (PCA) was applied to coordinates to determine the covariant function of the proposed mechanism. dMRI data were acquired from 11 healthy subjects during a repeated swallow task. Coordinates mapping the proposed mechanism were collected from each dynamic (frame) of a dMRI swallowing series of a randomly selected subject in order to demonstrate shape changes in a single subject. Coordinates representing minimum and maximum hyolaryngeal elevation of all 11 subjects were also mapped to demonstrate shape changes in the system among all subjects. MophoJ software was used to perform PCA and determine vectors of shape change (eigenvectors) for elements of the two-sling mechanism of hyolaryngeal elevation. For both single subject and group PCAs, hyolaryngeal elevation accounted for the first principal component of variation. For the single subject PCA, the first principal component accounted for 81.5% of the variance. For the between-subjects PCA, the first principal component accounted for 58.5% of the variance. Eigenvectors and shape changes associated with this first principal component are reported. Thus, it was concluded that eigenvectors indicate that two muscular slings and associated skeletal elements function as components of a covariant mechanism to elevate the hyolaryngeal complex. Also, morphological analysis is useful to model shape changes in the two-sling mechanism of hyolaryngeal elevation.

Imaging the cadavers being dissected does not appear to improve the gross anatomy dissection experience

In their Letter to the Editor entitled “Are computed tomography scans of cadavers perceived as a useful educational adjunct in a surgical anatomy course?” Cornwall and Stringer argue that incorporating CT scans of the actual cadavers being dissected is of limited value in a surgical anatomy course (Cornwall and Stringer, 2014). The authors of this letter cite our study (Lufler et al., 2010), in which we examined the utility of providing CT scans of some of the cadavers being dissected in a large first-year medical gross anatomy course. Despite numerous methodological differences, the conclusions of both studies are consistent with each other. In the study by Lufler et al. (2010), we provided the CT scans of four of the 22 bodies being dissected in the first year medical gross anatomy course. All students had access to the scans, but only 18% of the students dissected the bodies that had been scanned. Individual student use of the scans was tracked by requiring that individuals log in to the computers in order to access the scans. The results of that study demonstrated that those individuals who used the scans performed more strongly on numerous measures of academic performance in the course. However, there were no differences in performance between students who dissected the specific cadaver that was scanned and those that dissected one of the other bodies. Despite being targeted at different populations (first-year undergraduate medical students versus surgical residents) and having used different methods of assessment (examination grades versus surveys), our study and that of Cornwall and Stringer find similar conclusions. Namely, making available the scans of the actual cadavers being dissected does not seem to impart any benefit beyond that of providing a generic CT scan. However, the methodological differences between the studies should be emphasized. Unlike Cornwall and Stringer, we did not solicit any feedback from the students to determine how they perceived the CT scans educationally. It is possible that the students who used the CT scans in our study felt that this practice was educationally useful, even if their examination scores later proved to be indistinguishable from those of their peers. Because of the different methodologies it is difficult to directly compare the results of these two studies. Both sets of authors also make the caveat that this conclusion may change if trainees are required to correlate their dissections with their scans in some way. The students’ use of the CT scans in both of these studies was optional and self-directed. It has been shown that self-directed learning principles can elicit mixed feedback from students on their educational value (Bergman et al., 2013). In our study, students with kinesthetic learning styles were most likely to use the scans, indicating that selfdirected use of scans in the laboratory may only be appealing to a subset of the trainees. Given any lack of concrete purpose for the scans, it is not surprising that there was no obvious benefit to being able to correlate the scans to particular cadavers. However, it is not difficult to imagine educational scenarios in which it would be very useful to be able to correlate cadaverspecific CT scans with the students’ dissection activities. For example, Bohl et al. (2011) describe the use of web-based, selfguided clinical cases based on findings in postmortem CT scans of the cadavers in their first-year undergraduate course. Similarly, Jacobson et al. (2009) describe the creation of “virtual patients” from the CT scans of the cadavers in their laboratory. The pathological findings from the CT images were used to develop plausible clinical cases designed to highlight and explain the abnormal anatomic findings encountered during the cadaveric dissection. In both of these studies, students were encouraged but not required to use these cases. However, with little additional work, tasks could be designed that require the students dissecting the scanned cadavers to use these virtual patients’ findings to prospectively guide their dissections, especially in the context of interesting pathologies or anomalies. In conclusion, Cornwall and Stringer (2014) generally agree with our conclusions by Lufler et al. (2010) that there is limited utility of providing the CT scans of the actual cadavers being dissected. It is reasonable to postulate that activities could be designed that would increase the utility of scanning the actual bodies being dissected. However, the pedagogical benefit of such activities must be weighed against the significant financial and time expenses required to acquire the scans and produce the corresponding educational tasks every year. Although the benefit of scanning the same donors may be limited, evidence does support a robust educational benefit of providing generic high quality radiological images in the gross anatomy laboratory.