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Death following retrobulbar injection of desmopressin for the treatment of non arteritic anterior ischemic optic neuropathy. Which implications of this off-label use?
No full textImplications of Postmortem Magnetic Resonance Imaging in Sudden Cardiac Death
No full textAfter attending this presentation, attendees will understand the importance of the execution of a postmortem cardiac Magnetic
Resonance Imaging (MRI) for the detection of cardiac alterations and as a guide for histological collection in the early stage of
Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D).
This presentation will impact the forensic science community by showing that the interpretation of postmortem radiology, especially
in the cardiovascular field, can help the examiner in performing the autopsy
.
ARVC/D is characterized by fibro-fatty replacement of the Right Ventricular (RV) myocardium and by ventricular arrhythmias
as the main clinical manifestation. It represents an important cause of sudden death in young people. A genetic inheritance can be
demonstrated in at least 40%-50% of the cases.
A case of a fatal arrhythmia that occurred at home in a 25-year-old man due to an early phase of ARVC/D is reported. An autopsy
was carried out in order to determine the cause of death. The execution of a cardiac MRI — performed before the examination of the
heart — was crucial to point out two areas of fatty infiltration not evidenced macroscopically. Histological examination of the specimens
collected under the guidance of imaging was suggestive for typical alterations of ARVC/D whereas no signs of infiltration were observed
in other cardiac specimens.
Case Report:
A 25-year-old male student suddenly collapsed in his apartment before sleeping at night. The event was witnessed
by his girlfriend. Cardiopulmonary resuscitation initiated in a few minutes by an emergency physician was unsuccessful. The family
denied any previous pathology. Family history was negative for sudden death or cardiomyopathy. A complete postmortem examination
was performed 24 hours after death. External examination was insignificant. At internal examination, the pericardium was opened
anteriorly revealing the enclosed heart. The great arteries were transected 3cm above the aortic and pulmonary valves, the pulmonary
veins and the superior and inferior vena cava, and the heart was removed. It was normal in size and weighed 360g. Other organs were
unremarkable. Blood and a full-thickness block of myocardium were retained (frozen) pending onward referral for genetic testing. After
routine autopsy, the heart was suspended and fixated at room temperature with 10% buffered formaldehyde solution. After 24 hours of
fixation, a cardiac MRI was performed using a 1.5T clinical scanner using a brain bird-cage multichannel coil. MRI protocol included
a whole heart 3D-SSFP acquisition with the following parameters: slice thickness 1mm (interpolated to 0.5mm), NEX 1, FOV 19cm,
matrix 512x512, 60° flip angle, TR/TE equal to 8.4/4.1. FSE images with the following parameters were also acquired: slice thickness
2mm, NEX 1, FOV 32cm, matrix 256x256, 90° flip angle, TR/TE equal to 840/8.1. In 3D-SSFP images, two focal areas of suspected
fat infiltration were detected in the sub-tricuspidalic region and in the lateral free-wall. These regions with suspected fat infiltration
were also evidenced in FSE images. The heart underwent macroscopic examination: coronary vessels and main branches, examined by
multiple cross sections, were normal; no atherosclerotic lesions were detected; RV wall thickness was 0.4cm. The investigation of the
two areas clearly highlighted by MRI revealed small foci of fat infiltration without clear pathological significance. Full-thickness blocks
of myocardium were removed for histological examination from anterior, lateral, and posterior left ventricular free wall, from ventricular
septum, from RV outflow tract, and from both atria, according to the recommended guidelines for best practice. Furthermore, other
samples were obtained directly from the areas indicated by the MRI (as being suggestive for fat infiltration). Specimens were embedded
in paraffin and routinely processed.
The histological examination of “MRI guided” cardiac specimens, stained with haematoxylin-eosin and Masson, revealed fibrous
and fatty tissue replacement that had swept inwards from the epicardial aspect to the endocardial aspect of the ventricle chamber.
Myocardial disarray, lymphocytic infiltrates, and foci of contraction band necrosis were also observed. No remarkable alterations were
detected in all other cardiac specimens. Postmortem toxicological analyses were negative for alcohol, drugs, and common toxicants.
The cause of death was attributed to ARVC/D
Death Following Retrobulbar Injection of Desmopressin for the Treatment of Non-Arteritic Anterior Ischemic Optic Neuropathy: Which Implications Indicate This Off-Label Use?
No full textAfter attending this presentation, attendees will be aware of the possible clinical and legal implications following off-label use of
corticosteroids and desmopressin for the treatment of Non-Arteritic Ischemic Optic Neuropathy (NAION).
This presentation will impact the forensic science community by illustrating a case of fatal acute myocardial infarction after
retrobulbar injection of a synthetic replacement of vasopressin.
Since a standard treatment for NAION with proven efficacy is not available to date, most therapeutic approaches are empirical
and include a wide range of agents presumed to act on thrombosis, on the blood vessels, on the disk edema, or presumed to have
a neuroprotective effect. Among other proposed treatments, retrobulbar injection of corticosteroid and desmopressin represents an
invasive approach, with potential for local and systemic complications, which does not appear to have been documented previously. The
rationale of using desmopressin in the treatment of NAION is uncertain and perhaps a result of experimental findings demonstrating that
desmopressin induces ciliary artery relaxation in dogs via V1-receptors through a mechanism which involves nitric oxide. In turn, this
would enhance vascular permeability, thus facilitating the re-absorption of optic edema. A similar vasodilation effect can be attributed
to corticosteroids.
A 60-year-old man, apparently healthy and with a negative history for cardiovascular disease, was hospitalized because of a unilateral
sudden and painless severe visual loss (20/200) upon waking in the morning. The optic disc appeared hyperemic and edematous, with
a focal severe swelling. Relative inferior altitudinal scotoma was present at visual field examination. The patient presented with an
erythrocyte sedimentation rate 20mm/h and normal levels of plasma fibrinogen and C-reactive protein. The diagnosis of NAION
was made. Two separate and immediately consecutive injections of betamethasone (2mg/0.5ml) and desmopressin (2mcg/0.5ml)
were performed in the retrobulbar space. The administration of any preoperative medication or cardiovascular examination was not
documented. In the patient’s medical records, the total volume of the injections and the size of the needle used are not specified. The
procedure was technically uncomplicated without any monitoring in progress during injections such as Electrocardiogram (ECG),
peripheral oxygen saturation, or blood pressure measurement. Fifteen minutes later, the patient suddenly developed a cold sweat,
dyspnea, thoracic pain, and severe hypotension. ST segment elevation acute myocardial infarction was diagnosed by ECG. Intensive
care support was initiated; however, despite cardiopulmonary resuscitation, the patient died from irreversible cardio-respiratory arrest.
At autopsy, the heart presented with a normal shape and weight (350g); coronary arteries showed significant atherosclerotic luminal
narrowing. Histological investigation showed a stenotic atherosclerotic plaque (95%) complicated by culprit thrombosis of the left
anterior descending artery, 2cm after its origin. Examination of the other organs was unremarkable, except for mild pulmonary edema
and polyvisceral stasis. There was no evidence of increased orbital volume or sign of vagal compression secondary to retrobulbar
hemorrhage.
Professional autonomy in the health care decision-making process renders the physician free to prescribe a drug for purposes other
than that for which it has been approved, when the physician considers it both safe and effective according to his/her professional
judgment.
The use of unlicensed and off-label medicines is a widely used medical practice, mainly in certain clinical settings. A physician’s
autonomy in healthcare decision-making represents an instrument to guarantee the progress and evolution of scientific knowledge while
also practicing the most effective safeguards for health protection and promotion.
Though off-label prescription use is common and sometimes necessary for providing a pathway to clinical practice innovation,
it presents significant risks. This practice may lack rigorous scientific scrutiny and there is little known about the degree of scientific
evidence supporting it. According to the literature, a high percentage (approximately the 73% of off-label use) had little or no scientific
confirmation. Unexpected adverse effects represent a possible risk. Since the off-label practice may expose patients to avoidable risks,
it is mandatory for doctors to follow the lawful direction and ethical recommendatio
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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