Mystery Case Research Articles

Verbal information exchange enhances collective performance through increasing group identification

Information exchange is a key factor in the attainment of collective outcomes and the navigation of social life. In the current study, we investigated whether and how information exchange enhanced collective performance by combining behavioral and neuroimaging approaches from the perspective of multiparticipant neuroscience. To evaluate collective performance, we measured the collaborative problem-solving abilities of triads working on a murder mystery case. We first found that verbal information exchange significantly enhanced collective performance compared to nonverbal exchange. Moreover, both group sharing and group discussion positively contributed to this effect, with group discussion being more essential. Importantly, group identification mediated the positive effect of verbal information exchange on collective performance. This mediation was supported by higher interactive frequency and enhanced within-group neural synchronization (GNS) in the dorsolateral prefrontal cortex (DLPFC). Taken together, we provided a multiparticipant theoretical model to explain how verbal information exchange enhanced collective performance. Our findings deepen the insight into the workings of group decision-making.

The feasibility of a mystery case curriculum to enhance diagnostic reasoning skills among medical students: a process evaluation.

Within a Hospital Medicine division at a large academic institution, an innovative program has been developed to offer third year medical learners enrolled in their Internal Medicine Clerkship the opportunity to deepen their diagnostic reasoning skills with a weekly case-based learning activity entitled "Hospital Medicine's Mystery Case of the Week". The mystery case curriculum has four primary learning objectives (1): To understand the value of employing a multisystem approach to a common presenting problem (2); To apply a diagnostic schema to a clinical problem (3); To apply knowledge of cost appropriate workups to a clinical case and (4) To identify cognitive biases that can influence decision making in the context of treating a clinical problem. A process evaluation of the mystery case curriculum was conducted over a 6-month implementation period. The process evaluation was guided by eight domains of focus: program acceptability, demand, implementation, practicality, adaptation, integration, expansion and limited-efficacy testing. Measures included a pre/post mixed-methods survey, attendance log and timesheet. Pre/post survey data was analyzed via paired samples t-tests and open-ended responses were analyzed via a deductive content analysis. Process evaluation findings demonstrated the program had high levels of acceptability and demand. Survey findings suggest the curriculum may increase feelings of preparedness for Internal Medicine exams as well as student interest, comfort and confidence related to diagnostic processes. Future evaluations should work to understand the influence this curriculum has on diagnostic accuracy within a clinical setting.

COVID-19 epidemic modelling for policy decision support in Victoria, Australia 2020–2021

BackgroundPolicy responses to COVID-19 in Victoria, Australia over 2020–2021 have been supported by evidence generated through mathematical modelling. This study describes the design, key findings, and process for policy translation of a series of modelling studies conducted for the Victorian Department of Health COVID-19 response team during this period.MethodsAn agent-based model, Covasim, was used to simulate the impact of policy interventions on COVID-19 outbreaks and epidemic waves. The model was continually adapted to enable scenario analysis of settings or policies being considered at the time (e.g. elimination of community transmission versus disease control). Model scenarios were co-designed with government, to fill evidence gaps prior to key decisions.ResultsUnderstanding outbreak risk following incursions was critical to eliminating community COVID-19 transmission. Analyses showed risk depended on whether the first detected case was the index case, a primary contact of the index case, or a ‘mystery case’. There were benefits of early lockdown on first case detection and gradual easing of restrictions to minimise resurgence risk from undetected cases. As vaccination coverage increased and the focus shifted to controlling rather than eliminating community transmission, understanding health system demand was critical. Analyses showed that vaccines alone could not protect health systems and need to be complemented with other public health measures.ConclusionsModel evidence offered the greatest value when decisions needed to be made pre-emptively, or for questions that could not be answered with empiric data and data analysis alone. Co-designing scenarios with policy-makers ensured relevance and increased policy translation.

S3182 The Mystery Case of Chronic Thrombocytopenia in a Firefighter

S3182 The Mystery Case of Chronic Thrombocytopenia in a Firefighter

COVID-19 Sudden Outbreak of Mystery Case Transmissions in Victoria, Australia, May-June 2021: Strong Evidence of Tropospheric Transport of Human Passaged Infective Virions from the Indian Epidemic

COVID-19 Sudden Outbreak of Mystery Case Transmissions in Victoria, Australia, May-June 2021: Strong Evidence of Tropospheric Transport of Human Passaged Infective Virions from the Indian Epidemic

Mystery Case of Parathyroid Carcinoma Masquerading as a Thyroid Nodule

Introduction: Parathyroid carcinoma is a rare malignancy with a prevalence of 0.005%. Patients typically present with symptoms of hypercalcemia and elevated parathyroid hormone (PTH) levels. Non-functional parathyroid carcinoma presenting with neck pain and normal calcium is a unique and challenging entity. We describe a challenging case of normocalcemic parathyroid carcinoma presenting as neck pain. Case Description: A 59-year old woman with a history of asthma, type 2 diabetes, and tobacco use presented with neck pain and swelling worsening over months. On physical exam, she was noted to have right-sided thyroid mass. CT scan of the neck showed an enlarged thyroid gland with a 1.6 cm nodule with evidence of the trachea’s compression. Subsequent thyroid US revealed a 2.1 cm dominant solid, hypoechoic nodule in the right thyroid lobe. Initial testing revealed normal calcium levels; however, PTH level was not available. FNA of the nodule was non-diagnostic with subsequent repeat FNA interpreted as benign mass. Due to suspicious imaging features and significant neck discomfort, she underwent right hemithyroidectomy. During the surgery, the nodule was noted to be invasive with evidence of extrathyroidal extension. Postoperatively calcium was 8.9 mg/dl (8.6–10.4 mg/dl), ionized calcium 4.7 mg/dl (4.8–5.6mg/dl), PTH 48 pg/mL (14–64 pg/ml), and vitamin D25OH 48 ng/dL (30-100ng/dl). TSH was mildly elevated at 4.59 uIU/ml (0.27–4.2 uIU/ml) with free T4 of 1.09 ng/dl (0.93–1.70ng/dl). The preliminary pathology report described follicular thyroid carcinoma; however, immunostains failed to confirm primary thyroid cancer. The lesion was negative for TTF-1, PAX8, TG, CEA, calcitonin, chromogranin, and synaptophysin. The tumor was strongly positive for GATA3, PTH and positive in nuclear staining for parafibroma. The specimen was evaluated by two pathologists who favored the diagnosis of parathyroid carcinoma. A separate incidental microscopic 4mm papillary thyroid carcinoma (PTC) was found and tested positive for BRAF mutation. Genetic testing for CDC73 was negative. PET scan showed increased uptake in the right thyroid bed. Given microscopic PTC and mildly elevated TSH, she was started on levothyroxine. The patient recovered successfully after the surgery with the resolution of symptoms. She was evaluated by an oncologist, and adjuvant radiation therapy was recommended. Conclusion: Non-functional parathyroid carcinoma is a unique entity, and its diagnosis may be delayed given an atypical presentation and normal endocrine function. Differentiation between nonfunctioning parathyroid carcinoma, parathyroid adenoma, and thyroid disease based on location and proximity to the thyroid may be challenging. Although concomitant thyroid disease is not uncommon, synchronous thyroid cancer is very rare.

Xanthelasmata secondary to underlying vasculopathy: A mystery case report

Xanthelasmata secondary to underlying vasculopathy: A mystery case report

Mystery Case: Parietal lobe epilepsy with ictal manifestation of Gerstmann syndrome

Gerstmann syndrome, comprising finger agnosia, right–left disorientation, dysgraphia, and dyscalculia, is an uncommon manifestation of epileptic seizures. These signs can be easily overlooked unless tested specifically.

Teaching Medical Students Optimal Consulting Skills: The Challenge of Generating Better Referring Physicians.

Rationale and objectivesWe sought to incorporate a new teaching module into the traditional medical student radiology clerkship, to improve the necessary skills for future referring physicians.Materials and methodsA new required and graded module was introduced in 2014 into the radiology clerkship in year three of medical school: the Mystery Case. Each student was provided a unique and undifferentiated case from a dedicated teaching file containing de-identified images and requisition data. Students were expected to complete three serial tasks over one week: 1) prepare a voice recognition-derived, structured radiological report utilizing appropriate and relevant vocabulary; 2) discuss pertinent additional clinical information; and 3) discuss appropriate follow-up imaging, in addition to information on how to best prepare patients for these potential patient exams (e.g., with or without contrast, bowel preparation, and length of study). Students were provided written examples and dedicated class instruction with interactive discussions covering specific cases and associated related cases through random pairing with radiology resident and attending mentors. At the close of the week, students gave brief oral presentations of their cases and submitted the tasks for a written evaluation. Upon completion of the clerkship, the students completed a Likert-type six-item survey to evaluate the perceived improvement in select skills.ResultsThe survey was completed by 82% (54/66) of the enrolled students, with 85% finding the Mystery Case an effective use of time. Medical students perceived an improved awareness of the patient care process (77%), awareness of the medical imaging resources available (89%), ability to understand a radiology report (74%), and ability to advise patients (69%).ConclusionIntroduction of the Mystery Case as a graded exercise in the medical school radiology clerkship was perceived by students as effective use of time, with an improvement in the skills essential for future referring physicians.

Mystery Case: Missed diagnosis of hereditary hemorrhagic telangiectasia presenting with recurrent ischemia

A 35-year-old patient presented with hemianopia, decreased consciousness, and bilateral cortical foci of restricted diffusion (figure). Investigations for migraine, vasculitis, and cardiogenic stroke were negative. Four months later, the patient developed left foot claudication and discoloration. She was found to have lingual mucocutaneous telangiectasias and epistaxis. Further workup revealed pulmonary and cerebral arterial–venous malformations (AVMs). The patient met 3/4 Curacao criteria and had a definite hereditary hemorrhagic telangiectasia (HHT) diagnosis. Paradoxical emboli were the cause of her infarcts and lower extremity ischemia.

Reader response: Mystery Case: Bilateral temporal crescent sparing after cardiac arrest.

I was surprised that the Mystery Case by Lindegger et al.1 was published in the Resident & Fellow Section. Although there is clear temporal crescent sparing, there are also smaller—but equally clear—residual nasal crescents in both the superior and inferior fields that cross the vertical meridian. The case seems to teach that the anterior most portion of the calcarine cortex has not only peripheral temporal fibers, but also fibers serving a peripheral nasal crescent.

Editors' note: Mystery Case: Bilateral temporal crescent sparing after cardiac arrest

In their Mystery Case, Lindegger et al. presented the unique visual fields of a middle-aged man who complained of tunnel vision 6 months following a cardiac arrest. One challenge to the case was the appearance of the Goldmann perimetry findings, which are nearly the opposite of what would be seen in a lesion affecting the optic chiasm. Instead of having bitemporal loss of vision, the patient had sparing of the most peripheral temporal visual fields with additional sparing of the binocular central fields. Among the 394 survey responses to the case, only 22% of readers correctly localized the lesion to the bilateral calcarine cortex (38% localized the lesion incorrectly to the chiasm). Dr. Rosenberg, a neuro-ophthalmologist, appropriately considers these Goldmann visual field findings controversial, and even contrary to our current understanding of visual pathways. Sparing of the far peripheral nasal fields and crossing of the vertical meridian peripherally would be untenable for bilateral occipital lobe lesions and probably explains why the survey participants had great difficulty localizing the lesion. Lindegger et al. respond that the manual perimetry was performed by an experienced technician, but that some of these atypical visual field findings may have resulted from the fixation losses and cognitive impairment that follows cardiac arrest. In the article “Deep brain stimulation improves restless legs syndrome in patients with Parkinson disease,” Dr. Klepitskaya et al. reported sustained improvement in symptoms of restless legs syndrome (RLS) over 2 years in 22 patients with Parkinson disease (PD) who underwent subthalamic nucleus (STN) deep brain stimulation (DBS), despite a decrease in dopaminergic treatment. Drs. Marques et al. point out that the article misinterpreted the results of their previous study, which showed an emergence of RLS in patients with PD with a higher dose of dopamine agonists and a lower decrease in dopaminergic treatment after STN DBS.

Author response: Mystery Case: Bilateral temporal crescent sparing after cardiac arrest.

My coauthors and I appreciate Dr. Rosenberg's comments on our article,1 and we agree in principle. The scope of the case report did not allow for the elaboration of the additional teaching points that Dr. Rosenberg elucidates, namely that there may be a contribution by the so-called peripheral nasal crescent, and that central sparing is typically very congruous. The visual field published is a copy of the exact visual field as it was obtained in the acute clinical setting.1 It depicts precisely what was extracted from the patient shortly after the original CNS insult by an experienced perimetrist. The patient was not cognitively entirely fit at the time due to the insult itself, which limits the precision of perimetry. However, it demonstrates the main principles offered as teaching points in the short communication. Regarding the comment pertaining to the notch, it is difficult to demonstrate such a finding even by experienced perimetrists, let alone in patients coming out of the intensive care unit.

E-Marketing Campaign for a University. Case Study

Abstract The subject of this work is an e-marketing campaign for a university from theoretical and practical perspective. Starting from a definition of e-marketing and the set of instruments used in e-marketing, the stages of implementation of e-marketing campaigns dedicated to entities from the sector of education will be discussed. Methodology of research for the purposes of the article covered literature studies, meta-analysis of available Internet sources and authors’ own qualitative research with the application of the methods of mystery client and case study. The object of the research is a private university and the subject of research are e-marketing activities, including identified campaigns, conducted for the university. The authors’ goal is to present an e-marketing campaign for a university in theory and practice. The purpose of the article is working out guidelines and recommendations for marketing specialists interested in efficient marketing activities on the Internet for the analyzed entities.

Mystery Case: Eccentric target sign in CNS toxoplasmosis: A rare presentation of Good syndrome.

A 61-year-old man with myasthenia gravis who previously underwent post-thymectomy radiotherapy for a metastatic thymoma presented with altered mental status. Examination revealed papilledema and frontoexecutive dysfunction.

Inelastic transverse magnetic dipole electron scattering form factors in 48Ca (restricted optimum configurations)

Inelastic transverse magnetic dipole electron scattering formfactors in 48Ca have been investigated through nuclear shell modelin an excited state energy Ex= 10.23 MeV which is so called"mystery case" with different optional choices like effectiveinteraction, restricted occupation and core polarization interaction.40Ca as an inert core will be adopted and four orbits with eightparticles distributed mainly in 2p1f model space and in some extendrestricted to make sure about the major accuse about this type oftransition. Theoretical results have been constituted mainly withexperimental data and compared with some important theoreticalresults of the same transition.

Editors' note: Mystery Case: A case of fulminant encephalopathy in a 69-year-old woman

In “Mystery Case: A case of fulminant encephalopathy in a 69-year-old woman,” Dr. Lamotte and Williams discuss fat embolic encephalopathy in a patient with sickle cell disease. Commenting on the article, Dr. Ganesh wonders about the diagnosis of sarcoidosis and the absence of a right-to-left shunt in the patient. He also suggests that transcranial Doppler imaging can be more sensitive than echocardiography in identifying right-to-left shunts. In response, Dr. Lamotte explains that there is no known association between sarcoidosis and fat emboli syndrome. He adds that the use of transcranial Doppler in the detection of right-to-left shunt, which requires active participation of the patient with immediate feedback provided by forced expiration against a manometer to 40 mm Hg, would not have been possible in their comatose patient. In “Mystery Case: A case of fulminant encephalopathy in a 69-year-old woman,” Dr. Lamotte and Williams discuss fat embolic encephalopathy in a patient with sickle cell disease. Commenting on the article, Dr. Ganesh wonders about the diagnosis of sarcoidosis and the absence of a right-to-left shunt in the patient. He also suggests that transcranial Doppler imaging can be more sensitive than echocardiography in identifying right-to-left shunts. In response, Dr. Lamotte explains that there is no known association between sarcoidosis and fat emboli syndrome. He adds that the use of transcranial Doppler in the detection of right-to-left shunt, which requires active participation of the patient with immediate feedback provided by forced expiration against a manometer to 40 mm Hg, would not have been possible in their comatose patient.

Author response: Mystery Case: A case of fulminant encephalopathy in a 69-year-old woman.

I thank Dr. Ganesh for the interesting comment on our Mystery Case.1 The patient had a diagnosis of pulmonary sarcoidosis (biopsy-proven) 30 years prior to presentation at our institution, but was not on any sarcoidosis treatment for the last 10 years. We agree that neurosarcoidosis can present with a variety of neurologic symptoms, including, but not limited to, cranial neuropathies, meningeal disease, hypothalamic-pituitary axis involvement, and sclerotic or osteolytic lesions.2 However, to our knowledge, there is no known association between sarcoidosis and fat emboli syndrome. We thank Dr. Ganesh for bringing to our attention the study comparing transcranial Doppler vs intracardiac echocardiography in the detection of right-to-left shunt.3 The protocol used in that study required active participation of the patient with immediate feedback provided by forced expiration against a manometer to 40 mm Hg. This method would not have been possible in our comatose patient.1 Furthermore, the pathophysiology of fat embolism syndrome in patients with sickle cell disease is unclear and a biochemical theory has also been proposed, suggesting that fat embolism syndrome may be secondary to a proinflammatory state with high concentrations of glycerol and toxic free fatty acids causing emboli in the arterial circulation.4

Reader response: Mystery Case: A case of fulminant encephalopathy in a 69-year-old woman.

I enjoyed reading the Resident & Fellow Section Mystery Case by Drs. Lamotte and Williams1 on fat embolic encephalopathy in a patient with sickle cell disease. However, there is a potentially confusing point that requires clarification by the authors.

Mystery Case: CSF-1R mutation is a cause of intracranial cerebral calcifications, cysts, and leukoencephalopathy.

Mystery Case: CSF-1R mutation is a cause of intracranial cerebral calcifications, cysts, and leukoencephalopathy.