Blue–Yellow VEP with Projector-Stimulation in Glaucoma

Abstract Background and aim In the past, increased latencies of the blue-on-yellow pattern visually evoked potentials (BY-VEP), which predominantly originate in the koniocellular pathway, have proven to be a sensitive biomarker for early glaucoma. However, a complex experimental setup based on an optical bench was necessary to obtain these measurements because computer screens lack sufficient temporal, spatial, spectral, and luminance resolution. Here, we evaluated the diagnostic value of a novel setup based on a commercially available video projector. Methods BY-VEPs were recorded in 126 participants (42 healthy control participants, 12 patients with ocular hypertension, 17 with “preperimetric” glaucoma, and 55 with perimetric glaucoma). Stimuli were created with a video projector (DLP technology) by rear projection of a blue checkerboard pattern (460 nm) for 200 ms (onset) superimposed on a bright yellow background (574 nm), followed by an offset interval where only the background was active. Thus, predominantly S-cones were stimulated while L- and M-cone responses were suppressed by light adaptation. Times of stimulus onset to VEP onset-trough (N-peak time) and offset-peak (P-peak time) were analyzed after age-correction based on linear regression in the normal participants. Results The resulting BY-VEPs were quite similar to those obtained in the past with the optical bench: pattern-onset generated a negative deflection of the VEP, whereas the offset-response was dominated by a positive component. N-peak times were significantly increased in glaucoma patients (preperimetric 136.1 ± 10 ms, p < 0.05; perimetric 153.1 ± 17.8 ms, p < 0.001) compared with normal participants (123.6 ± 7.7 ms). Furthermore, they were significantly correlated with disease severity as determined by visual field losses retinal nerve fiber thinning (Spearman R = –0.7, p < 0.001). Conclusions Video projectors can be used to create optical stimuli with high temporal and spatial resolution, thus potentially enabling sophisticated electrophysiological measurements in clinical practice. BY-VEPs based on such a projector had a high diagnostic value for detection of early glaucoma. Registration of study Registration site: www.clinicaltrials.gov Trial registration number: NCT00494923.

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The Continuing Need for Electron Microscopy in Examination of Medical Renal Biopsies: Examples in Practice

Glomerular Diseases ◽

10.1159/000516831 ◽

2021 ◽

pp. 1-15

Author(s):

Michifumi Yamashita ◽

Mercury Y. Lin ◽

Jean Hou ◽

Kevin Y.M. Ren ◽

Mark Haas

Keyword(s):

Electron Microscopy ◽

Renal Biopsy ◽

Renal Allograft ◽

Comprehensive Evaluation ◽

Diagnostic Value ◽

Ultrastructural Studies ◽

The Past ◽

Biopsy Diagnosis ◽

Renal Biopsies ◽

Clinical Consequences

Background: For the better part of the past 6 decades, transmission electron microscopy (EM), together with routine light microscopy and immunofluorescence and/or immunohistochemistry (IHC), has been an essential component of the diagnostic workup of medical renal biopsies, particularly native renal biopsies, with increasing frequency in renal allograft biopsies as well. Studies performed prior to the year 2000 have indeed shown that a substantial fraction of renal biopsies cannot be accurately diagnosed without EM. Still, EM remains costly and labor-intensive, and with increasing pressure to reduce healthcare costs, some centers are de-emphasizing diagnostic EM. This trend has been coupled with advances in IHC and other methods in renal biopsy diagnosis over the past 2–3 decades. Summary: Nonetheless, it has been our experience that the diagnostic value of EM in the comprehensive evaluation of renal biopsies remains similar to what it was 20–30 years ago. In this review, we provide several key examples from our practice where EM was essential in making the correct renal biopsy diagnosis, ranging from relatively common glomerular lesions to rare diseases. Key Messages: EM remains an important component of the diagnostic evaluation of medical renal biopsies. Failure to perform EM in certain cases will result in an incorrect diagnosis, with possible clinical consequences. We strongly recommend that tissue for EM be taken and stored in an appropriate fixative and ultrastructural studies be performed for all native renal biopsies, as well as appropriate renal allograft biopsies as recommended by the Banff consortium.

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Necessity of dural tenting sutures in modern neurosurgery: protocol for a systematic review

BMJ Open ◽

10.1136/bmjopen-2018-027904 ◽

2019 ◽

Vol 9 (2) ◽

pp. e027904 ◽

Cited By ~ 1

Author(s):

Łukasz Przepiórka ◽

Przemysław Kunert ◽

Jarosław Żyłkowski ◽

Jan Fortuniak ◽

Patrycja Larysz ◽

...

Keyword(s):

Systematic Review ◽

Systematic Reviews ◽

Meta Analysis ◽

Potential Space ◽

Inclusion Criteria ◽

The Past ◽

Prisma Statement ◽

Ethical Committee Approval ◽

Registration Number ◽

Review Protocol

IntroductionThe ongoing need for dural tenting sutures in a contemporary neurosurgical practice has been questioned in the literature for over two decades. In the past, these sutures were supposed to prevent blood collecting in the potential space between the skull and the dura by elevating the latter. Theoretically, with modern haemostasis and proper postoperative care, this technique should not be necessary and the surgery time can be shortened. Unfortunately, there is no evidence-based proof to either support or reject this hypothesis.Methods and analysisThe systematic review will be performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement and The Cochrane Handbook for Systematic Reviews of Interventions. Eight electronic databases of peer-reviewed journals will be searched, as well as other sources. Eligible articles will be assessed against inclusion criteria. The intervention is not tenting the dura and this will be compared with the usual dural tenting sutures. Where possible, ‘summary of findings’ tables will be generated.Ethics and disseminationEthical committee approval is not required for a systematic review protocol. Findings will be presented at international neurosurgical conferences and published in a peer-reviewed medical journal.PROSPERO registration numberCRD42018097089.

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M-wave of proximal retina in cat

Journal of Neurophysiology ◽

10.1152/jn.1986.56.4.1039 ◽

1986 ◽

Vol 56 (4) ◽

pp. 1039-1048 ◽

Cited By ~ 16

Author(s):

P. A. Sieving ◽

L. J. Frishman ◽

R. H. Steinberg

Keyword(s):

Light Adaptation ◽

Pattern Electroretinogram ◽

Stimulus Onset ◽

Stray Light ◽

M Wave ◽

Stimulus Response ◽

Response Characteristics ◽

Cat Retina ◽

Small Spot ◽

Dc Component

There has been relatively little known about responses from proximal retina in mammals that could contribute to the electroretinogram (ERG). Recently, there has been evidence that the proximal retina is involved in generating the pattern electroretinogram (PERG). In the present work we investigated proximal retinal activity in the intact cat eye during light adaptation. Extracellular potentials evoked in response to circular spots of light, flashed on steady backgrounds, were recorded with microelectrodes placed intraretinally at different depths. Prominent negative responses were found in proximal retina that could be identified as the M-wave previously observed only in cold-blooded retinas. Like the cold-blooded responses, the cat's M-wave consisted of negative-going potentials at stimulus onset and offset that were maximum in amplitude with small spots. By analogy to the cold-blooded data, the cat M-wave is presumed to be the extracellular voltage arising from Muller cell responses to K+ released by proximal retinal neurons. In addition, the cat M-wave only appeared with backgrounds at and above rod saturation and had short latencies (30 ms) at stimulus onset and offset, indicating that it is a cone-driven response. The M-wave could be clearly distinguished from PII (b-wave and DC component) on the basis of its form, depth distribution, and stimulus-response characteristics. For example, photopic PII had its maximum voltage in the distal retinal at 55% retinal depth, whereas the M-wave was maximal in the proximal retina at 25% retinal depth. Also, PII simply increased in amplitude as stimulus spots were enlarged, whereas the M-wave exhibited spatial tuning. Under light-adapted conditions and with small-spot stimuli the M-wave is the largest extracellular voltage in cat retina. By recording the vitreal ERG near the retinal surface with the microelectrode referenced to a silver wire in the vitreous, we found that the M-wave in response to a small spot always had a negative polarity in the vitreous. Thus, unlike PII, the M-wave does not reverse polarity at the vitreo-retinal border. Because of stray-light effects, however, we were not able to assess the amplitude of the M-wave's contribution to the ERG obtained with diffuse retinal illumination. We conclude that the M-wave is present in the cat as a prominent cone-driven response of proximal retina that is separate from the b-wave, and whose significance for electroretinographic recordings remains to be determined.

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Nuclear Medicine in Diagnosis of Prosthetic Valve Endocarditis: An Update

BioMed Research International ◽

10.1155/2015/127325 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Maria Musso ◽

Nicola Petrosillo

Keyword(s):

Nuclear Medicine ◽

Diagnostic Accuracy ◽

Prosthetic Valve ◽

Prosthetic Valve Endocarditis ◽

Diagnostic Value ◽

The Past ◽

Prosthetic Valves ◽

Duke Criteria ◽

Yearly Rate

Over the past decades cardiovascular disease management has been substantially improved by the increasing introduction of medical devices as prosthetic valves. The yearly rate of infective endocarditis (IE) in patient with a prosthetic valve is approximately 3 cases per 1,000 patients. The fatality rate of prosthetic valve endocarditis (PVE) remains stable over the years, in part due to the aging of the population. The diagnostic value of echocardiography in diagnosis is operator-dependent and its sensitivity can decrease in presence of intracardiac devices and valvular prosthesis. The modified Duke criteria are considered the gold standard for diagnosing IE; their sensibility is 80%, but in clinical practice their diagnostic accuracy in PVE is lower, resulting inconclusively in nearly 30% of cases. In the last years, these new imaging modalities have gained an increasing attention because they make it possible to diagnose an IE earlier than the structural alterations occurring. Several studies have been conducted in order to assess the diagnostic accuracy of various nuclear medicine techniques in diagnosis of PVE. We performed a review of the literature to assess the available evidence on the role of nuclear medicine techniques in the diagnosis of PVE.

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Molecular markers as risk factors for thyroid cancer

Terapevticheskii arkhiv ◽

10.26442/00403660.2019.10.000357 ◽

2019 ◽

Vol 91 (10) ◽

pp. 119-123

Author(s):

M O Rogova ◽

S V Novosad ◽

N S Martirosian ◽

L V Trukhina ◽

N A Petunina

Keyword(s):

Thyroid Cancer ◽

Thyroid Nodules ◽

Malignant Tumors ◽

Molecular Genetic ◽

Endocrine System ◽

Diagnostic Value ◽

Needle Aspiration ◽

Molecular Genetic Testing ◽

Papillary Cancer ◽

The Past

Thyroid cancer is the most common malignant tumor of the endocrine system. An increase in the incidence of thyroid cancer has been noted over the past decade, mainly due to papillary cancer. The influence of environmental factors, increased availability of medical care, including sensitive diagnostic tests, such as ultrasound and fine - needle aspiration (FNA), can affect the fact of the growth of this incidence. Palpation of thyroid gland has very low diagnostic value for detecting thyroid cancer, while thyroid ultrasound and FNA can detect malignant tumors in 20% of cases. Today, the FNA is the fastest, most accurate, economically accessible, and quite safe method for cytological diagnosis of the thyroid nodules. And molecular genetic testing of FNA samples could serve as an additional reliable diagnostic tool in the case of atypia of undetermined significance.

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Comparison Radiographs of Extremities in Childhood: Recommended Usage

PEDIATRICS ◽

10.1542/peds.65.1.a57 ◽

1980 ◽

Vol 65 (1) ◽

pp. A57-A58

Author(s):

David F. Merten ◽

Alvin H. Felman ◽

Norman Glaser ◽

William J. McSweeney ◽

William Northway ◽

...

Keyword(s):

The United States ◽

Diagnostic Value ◽

Radiologic Diagnosis ◽

Pediatric Practice ◽

Governmental Agencies ◽

The Past ◽

Orthopedic Surgeons ◽

Accepted Practice ◽

Extremity Injuries ◽

Rule Out

Extremity injuries, a common problem in pediatric practice, are responsible for a significant number of radiographic examinations performed on children each year. Radiologic diagnosis in these injuries may be complicated by the variable appearance of the growing skeleton, especially around the epiphyses and the physeal plate. In the past, it has been a common and accepted practice for pediatricians, generalists, orthopedic surgeons, and radiologists to obtain routinely radiographs of the uninjured limb1-3 for comparison with those of the injured extremity to rule out subtle fractures or dislocations. Recently, increasing concern about potential dangers of ionizing radiation, coupled with agitation from insurance carriers and governmental agencies to reduce escalating medical costs, has resulted in mounting pressure to limit diagnostic radiographic examinations. At the same time, however, rising malpractice litigation has, in many instances, forced physicians to obtain additional radiographic studies to "protect" themselves, especially in trauma cases. Radiographs of traumatized extremities contribute significant numbers of medicolegally oriented radiologic examinations each year. Although comparison views are no doubt helpful in some instances, until recently there has not been any effort to document the extent of use or diagnostic value of comparison views, especially those routinely obtained. Within the past two years there have been two studies on this problem. In 1977, a survey4 of pediatric radiologists throughout the United States and Canada sought to determine individual application of comparison views, whether selective or routine; factors that influence this use; extent of comparison views, whether single or multiple; and cost of the additional radiographic studies.

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MRI and muscle enzymes do not support the diagnosis of local anesthetic myotoxicity: a descriptive case series

Regional Anesthesia and Pain Medicine ◽

10.1136/rapm-2021-102772 ◽

2021 ◽

pp. rapm-2021-102772

Author(s):

Lauren Mahyar ◽

Joseph M Neal ◽

C Craig Blackmore ◽

Dane W Jackson ◽

Neil A Hanson ◽

...

Keyword(s):

Local Anesthetic ◽

Case Series ◽

Diagnostic Value ◽

Thigh Muscle ◽

Muscle Enzymes ◽

Muscle Enzyme ◽

Postoperative Mri ◽

Registration Number ◽

Total Knee ◽

Muscle Edema

BackgroundThe presence of thigh muscle edema as characterized by increased signal intensity on MRI has been used to support the diagnosis of presumed local anesthetic-induced myotoxicity reported after total knee arthroplasty (TKA) with continuous adductor canal block (CACB). However, neither postoperative baseline imaging appearance nor muscle enzyme values have been described in conjunction with this clinical scenario. Thus, the usefulness of MRI or enzymatic biomarkers of muscle injury for supporting the diagnosis of local anesthetic myotoxicity is unknown.MethodsThis descriptive case series documents postoperative MRI appearance of the ipsilateral upper leg, plus preoperative and postoperative creatine phosphokinase and aldolase values in volunteer patients who underwent uncomplicated TKA with CACB.ResultsIn 27 volunteer patients with no postsurgical evidence of clinically relevant myotoxicity, anterior thigh muscle edema was universally evident on imaging (n=12) and muscle enzyme values (n=19) were normal or only slightly elevated.ConclusionsThe non-specificity of these findings suggests that MRI and near normal muscle enzyme levels are of limited diagnostic value when there is clinical suspicion of local anesthetic myotoxicity in the setting of TKA with CACB.Trial registration numberNCT04821245.

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Visual Electrodiagnostic Testing in Birdshot Chorioretinopathy

Journal of Ophthalmology ◽

10.1155/2015/680215 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 9

Author(s):

Radouil Tzekov ◽

Brian Madow

Keyword(s):

Posterior Uveitis ◽

Peak Time ◽

Birdshot Chorioretinopathy ◽

Full Field ◽

Electrodiagnostic Testing ◽

The Past ◽

Therapeutic Decisions ◽

Visual Electrophysiology ◽

Comparison Of The Results ◽

Electrophysiological Methods

Birdshot chorioretinopathy (BSCR) is a rare form of autoimmune posterior uveitis that can affect the visual function and, if left untreated, can lead to sight-threatening complications and loss of central vision. We performed a systematic search of the literature focused on visual electrophysiology studies, including electroretinography (ERG), electrooculography (EOG), and visual evoked potentials (VEP), used to monitor the progression of BSCR and estimate treatment efficacy. Many reports were identified, including using a variety of methodologies and patient populations, which makes a direct comparison of the results difficult, especially with some of the earlier studies using nonstandardized methodology. Several different electrophysiological parameters, like EOG Arden’s ratio and the multifocal ERG response densities, are reported to be widely affected. However, informal consensus emerged in the past decade that the full-field ERG light-adapted 30 Hz flicker peak time is one of the most sensitive electrophysiological parameters. As such, it has been used widely in clinical trials to evaluate drug safety and efficacy and to guide therapeutic decisions in clinical practice. Despite its wide use, a well-designed longitudinal multicenter study to systematically evaluate and compare different electrophysiological methods or parameters in BSCR is still lacking but would benefit both diagnostic and therapeutic decisions.

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Characteristic Analysis of Complementary and Alternative Medicine in Randomized Controlled Trials of Oncology: A Comparison of Published Studies

Integrative Cancer Therapies ◽

10.1177/1534735417696722 ◽

2017 ◽

Vol 17 (2) ◽

pp. 551-557 ◽

Cited By ~ 3

Author(s):

Huiqing Zhang ◽

Geliang Yang ◽

Wei Zhang ◽

Wei Gu ◽

Yonghua Su ◽

...

Keyword(s):

Alternative Medicine ◽

Complementary And Alternative Medicine ◽

Controlled Trial ◽

Characteristic Analysis ◽

Randomized Controlled ◽

The Past ◽

Registration Rate ◽

Registration Number ◽

Basic Characteristics ◽

Complementary And Alternative

Background: Complementary and alternative medicine (CAM) has been widely used by cancer patients and oncologists in the past decades. The present study aimed to examine and compare the characteristics and registration status of published studies in a sample of recently published CAM randomized controlled trial (RCT) reports of oncology in leading journals of 3 categories: general and internal medicine (GIM), clinical oncology (CO), and CAM. Methods: Articles published in the top 5 journals of the 3 categories from 2006 to 2015 were searched in PubMed. Basic characteristics, registration information, impact factor, and citations were identified and extracted from the included RCTs. Data were summarized by frequency, mean, and median and compared using χ2 test and Kruskal-Wallis H test. Results: A total of 59 RCTs were included; among them, 34 (58%) could be identified with a registration number. GIM journals (15) enjoyed the highest average number of citations per article, followed by CO (12) and CAM (3) journals ( P < .0001). ClinicalTrials.gov was the most popular registry for these RCTs. Of the RCTs registered in ClinicalTrials.gov , 24% (4/17) of the published studies in CO journals put their results in the registry; however, no study in GIM and CAM journals put the result in the registry ( P = .372). Conclusion: The top GIM, CO, and CAM journals rarely published CAM RCTs of oncology from 2006 to 2015, and the CAM articles of oncology were less cited. However, there was a clear improvement in the trial registration rate over the past decades.

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Evidence assessing the diagnostic performance of medical smartphone apps: a systematic review and exploratory meta-analysis

BMJ Open ◽

10.1136/bmjopen-2017-018280 ◽

2017 ◽

Vol 7 (12) ◽

pp. e018280 ◽

Cited By ~ 22

Author(s):

Rahel Buechi ◽

Livia Faes ◽

Lucas M Bachmann ◽

Michael A Thiel ◽

Nicolas S Bodmer ◽

...

Keyword(s):

Systematic Review ◽

Diagnostic Accuracy ◽

Quality Assessment ◽

Meta Analysis ◽

Reporting Quality ◽

Diagnostic Value ◽

Summary Estimate ◽

Registration Number ◽

Business Source Premier ◽

Smartphone Sensors

ObjectiveThe number of mobile applications addressing health topics is increasing. Whether these apps underwent scientific evaluation is unclear. We comprehensively assessed papers investigating the diagnostic value of available diagnostic health applications using inbuilt smartphone sensors.MethodsSystematic Review—MEDLINE, Scopus, Web of Science inclusive Medical Informatics and Business Source Premier (by citation of reference) were searched from inception until 15 December 2016. Checking of reference lists of review articles and of included articles complemented electronic searches. We included all studies investigating a health application that used inbuilt sensors of a smartphone for diagnosis of disease. The methodological quality of 11 studies used in an exploratory meta-analysis was assessed with the Quality Assessment of Diagnostic Accuracy Studies 2 tool and the reporting quality with the ’STAndards for the Reporting of Diagnostic accuracy studies' (STARD) statement. Sensitivity and specificity of studies reporting two-by-two tables were calculated and summarised.ResultsWe screened 3296 references for eligibility. Eleven studies, most of them assessing melanoma screening apps, reported 17 two-by-two tables. Quality assessment revealed high risk of bias in all studies. Included papers studied 1048 subjects (758 with the target conditions and 290 healthy volunteers). Overall, the summary estimate for sensitivity was 0.82 (95 % CI 0.56 to 0.94) and 0.89 (95 %CI 0.70 to 0.97) for specificity.ConclusionsThe diagnostic evidence of available health apps on Apple’s and Google’s app stores is scarce. Consumers and healthcare professionals should be aware of this when using or recommending them.PROSPERO registration number42016033049.

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