Postictal suppression and seizure durations: A patient‐specific, long‐term
            iEEG
            analysis

AbstractBone remodeling identifies the process of permanent bone change with new bone formation and old bone resorption. Understanding this process is essential in many applications, such as optimizing the treatment of diseases like osteoporosis, maintaining bone density in long-term periods of disuse, or assessing the long-term evolution of the bone surrounding prostheses after implantation. A particular case of study is the bone remodeling process after dental implantation. Despite the overall success of this type of implants, the increasing life expectancy in developed countries has boosted the demand for dental implants in patients with osteoporosis. Although several studies demonstrate a high success rate of dental implants in osteoporotic patients, it is also known that the healing time and the failure rate increase, necessitating the adoption of pharmacological measures to improve bone quality in those patients. However, the general efficacy of these antiresorptive drugs for osteoporotic patients is still controversial, requiring more experimental and clinical studies. In this work, we investigate the effect of different doses of several drugs, used nowadays in osteoporotic patients, on the evolution of bone density after dental implantation. With this aim, we use a pharmacokinetic–pharmacodynamic (PK/PD) mathematical model that includes the effect of antiresorptive drugs on the RANK/RANK-L/OPG pathway, as well as the mechano-chemical coupling with external mechanical loads. This mechano-PK/PD model is then used to analyze the evolution of bone in normal and osteoporotic mandibles after dental implantation with different drug dosages. We show that using antiresorptive agents such as bisphosphonates or denosumab increases bone density and the associated mechanical properties, but at the same time, it also increases bone brittleness. We conclude that, despite the many limitations of these very complex models, the one presented here is capable of predicting qualitatively the evolution of some of the main biological and chemical variables associated with the process of bone remodeling in patients receiving drugs for osteoporosis, so it could be used to optimize dental implant design and coating for osteoporotic patients, as well as the drug dosage protocol for patient-specific treatments.

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Journey of the glenoid in anatomic total shoulder replacement

Shoulder & Elbow ◽

10.1177/1758573218790119 ◽

2018 ◽

Vol 11 (2) ◽

pp. 140-148 ◽

Cited By ~ 4

Author(s):

Alessandro Castagna ◽

Raffaele Garofalo

Keyword(s):

Shoulder Arthroplasty ◽

Current Practice ◽

Total Shoulder Arthroplasty ◽

Shoulder Function ◽

Patient Specific ◽

Glenoid Component ◽

Shoulder Replacement ◽

Final Destination ◽

Component Loosening

Anatomic total shoulder arthroplasty (TSR) has been shown to generate good to excellent results for patients with osteoarthritis and a functioning rotator cuff. Many studies have reported that the glenoid component loosening and failure remain the most common long-term complication of total shoulder arthroplasty. The approach to glenoid component is critical because a surgeon should consider patient-specific anatomy, preserving bone stock and joint line restoration, for a good and durable shoulder function. Over the years, different glenoid design and materials have been tried in various configurations. These include cemented polyethylene, uncemented metal-backed and hybrid implants. Although advances in biomechanics, design and tribology have improved our understanding of the glenoid, the journey of the glenoid component in anatomic total shoulder arthroplasty has not yet reached its final destination. This article attempts to describe the evolution of the glenoid component in anatomic TSR and current practice.

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Approach to the Patient with Endocrine Disorders

10.2310/im.1264 ◽

2016 ◽

Author(s):

Graham T McMahon ◽

Robert G. Dluhy

Keyword(s):

Chronic Care ◽

Adrenal Incidentaloma ◽

Hormone Deficiency ◽

Patient Specific ◽

Endocrine Disorders ◽

Endocrine Disease ◽

Endocrine Diseases ◽

Characteristic Sets ◽

Patients Experience

The distribution of hormones throughout the human body results in presentations of endocrine disease that are diffuse and variable. Although some endocrine syndromes result in characteristic sets of symptoms and features, most patients experience a limited number of components of the syndrome and may note symptoms that are not typically syndromic. This review discusses presentations of endocrine diseases and the endocrine patient. Specific attention is given to endocrine testing, which can be achieved by measuring the hormone itself, stimulating or suppressing a hormone feedback loop, or measuring peripheral hormone receptor function. The chronic care relationship is explored as many patients with endocrine diseases require extended chronic care to achieve control of abnormal hormonal systems. The dependency on chronic care necessitates that endocrinologists develop particular expertise in managing illnesses over the long term. Tables list hormones and their associated syndromes, clusters of contrasting symptoms and signs of over- and underactivity of the thyroid and adrenal glands, approaches to endocrine testing and treatment, and variability in selected hormone concentrations over time. Figures show diagnostic criteria related to hypercalcemia, growth hormone deficiency, acromegaly, and adrenal incidentaloma. The chronic care model is also represented. This review contains 4 highly rendered figures, 4 tables, and 12 references.

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Radiation protection perspective to recurrent medical imaging: what is known and what more is needed?

British Journal of Radiology ◽

10.1259/bjr.20210477 ◽

2021 ◽

pp. 20210477

Author(s):

Jenia Vassileva ◽

Ola Holmberg

Keyword(s):

Radiation Protection ◽

Current Knowledge ◽

Clinical History ◽

Patient Specific ◽

Individual Radiosensitivity ◽

Dose Saving ◽

End Stage ◽

Future Work ◽

Standardised Patient

This review summarises the current knowledge about recurrent radiological imaging and associated cumulative doses to patients. The recent conservative estimates are for around 0.9 million patients globally who cumulate radiation doses above 100 mSv, where evidence exists for cancer risk elevation. Around one in five is estimated to be under the age of 50. Recurrent imaging is used for managing various health conditions and chronic diseases such as malignancies, trauma, end-stage kidney disease, cardiovascular diseases, Crohn’s disease, urolithiasis, cystic pulmonary disease. More studies are needed from different parts of the world to understand the magnitude and appropriateness. The analysis identified areas of future work to improve radiation protection of individuals who are submitted to frequent imaging. These include access to dose saving imaging technologies; improved imaging strategies and appropriateness process; specific optimisation tailored to the clinical condition and patient habitus; wider utilisation of the automatic exposure monitoring systems with an integrated option for individual exposure tracking in standardised patient-specific risk metrics; improved training and communication. The integration of the clinical and exposure history data will support improved knowledge about radiation risks from low doses and individual radiosensitivity. The radiation protection framework will need to respond to the challenge of recurrent imaging and high individual doses. The radiation protection perspective complements the clinical perspective, and the risk to benefit analysis must account holistically for all incidental and long-term benefits and risks for patients, their clinical history and specific needs. This is a step toward the patient-centric health care.

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Statistical Model-Based Classification to Detect Patient-Specific Spike-and-Wave in EEG Signals

10.20944/preprints202010.0616.v1 ◽

2020 ◽

Author(s):

Antonio Quintero Rincón ◽

Hadj Batatia ◽

Jorge Prende ◽

Valeria Muro ◽

Carlos D'Giano

Keyword(s):

Statistical Model ◽

Human Subjects ◽

True Positive Rate ◽

Wave Pattern ◽

Absence Epilepsy ◽

Patient Specific ◽

Eeg Signals ◽

True Negative ◽

Eeg Recordings

Spike-and-wave discharge (SWD) pattern detection in electroencephalography (EEG) signals is a key signal processing problem. It is particularly important for overcoming time-consuming, difficult, and error-prone manual analysis of long-term EEG recordings. This paper presents a new SWD method with a low computational complexity that can be easily trained with data from standard medical protocols. Precisely, EEG signals are divided into time segments for which the Morlet 1-D decomposition is applied. The generalized Gaussian distribution (GGD) statistical model is fitted to the resulting wavelet coefficients. A k-nearest neighbors (k-NN) self-supervised classifier is trained using the GGD parameters to detect the spike-and-wave pattern. Experiments were conducted using 106 spike-and-wave signals and 106 non-spike-and-wave signals for training and another 96 annotated EEG segments from six human subjects for testing. The proposed SWD classification methodology achieved 95 % sensitivity (True positive rate), 87% specificity (True Negative Rate), and 92% accuracy. These results set the path to new research to study causes underlying the so-called absence epilepsy in long-term EEG recordings.

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Early Outcomes of Patient-Specific Modular Cones for Substitution of Methaphysial and Diaphysial Bone Defects in Revision Knee Arthroplasty

Traumatology and Orthopedics of Russia ◽

10.21823/2311-2905-2019-25-2-9-18 ◽

2019 ◽

Vol 25 (2) ◽

pp. 9-18 ◽

Cited By ~ 1

Author(s):

A. A. Cherny ◽

A. N. Kovalenko ◽

S. S. Bilyk ◽

A. O. Denisov ◽

A. V. Kazemirskiy ◽

...

Keyword(s):

Three Dimensional ◽

Scoring Systems ◽

Bone Defects ◽

Patient Specific ◽

Implant Fixation ◽

Diaphyseal Bone ◽

Custom Made ◽

The Stability ◽

Valid Solution

The aim of this study was the assessment of early outcomes of patient-specific three-dimensional titanium cones with specified porosity parameters to compensate for extensive metaphysical-diaphyseal bone defects in RTKA.Materials and Methods. Since 2017 till 2019 30 patient-specific titanium cones (12 femoral and 18 tibial) implanted during 26 RTKAS. Clinical outcomes evaluated using KSS, WOMAC and fjS-12 scoring systems on average 10 (2–18) months after surgery. At the same time the stability of implant fixation analyzed using frontal, lateral and axial knee roentgenograms.Results. During all procedures there were no technical difficulties in positioning and implantation of custom-made titanium cones. At the time of preparation of the publication, none of the patients had indications for further surgical intervention, as well as intra- and postoperative complications. Six months after surgery all scores improved significantly: KSS from 23 (2–42, SD 19.96) to 66.5 (62–78, SD 7.68), WOMAC from 59 (56–96, SD 28.31) to 32.25 (19–46, SD 11.76), the index FJS-12 was 29.16 points (0–68.75, SD 30.19). The average scores continued to improve up to 18 months: KSS — 97.5 (88–108, SD 9.14), WOMAC — 16.5 (9–24, SD 6.45), FJS-12 — 45.85 (25–75, SD 22.03). No radiolucent lines were noticed during this period of observation.Conclusion. The original additive technology of designing and producing patient-specific titanium cones for compensation of extensive metaphyseal-diaphyseal bone defects in RTKA is a valid solution at least in the short term. A longer follow-up period is required to assess its medium-and long-term reliability compared to existing alternative surgical solutions.

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Connectivity-based thalamus parcellation and surgical targeting of somatosensory subnuclei

Journal of Neurosurgery ◽

10.3171/2021.7.jns211140 ◽

2021 ◽

pp. 1-8

Author(s):

Ashley L. B. Raghu ◽

Sean C. Martin ◽

Tariq Parker ◽

Tipu Z. Aziz ◽

Alexander L. Green

Keyword(s):

Electrode Array ◽

Leg Pain ◽

Patient Specific ◽

Chronic Neuropathic Pain ◽

Arm Pain ◽

Face Pain ◽

Pain Patients ◽

And Diffusion ◽

Term Benefit

OBJECTIVE The anatomy of the posterolateral thalamus varies substantially between individuals, presenting a challenge for surgical targeting. Patient-specific, connectivity-based parcellation of the thalamus may effectively approximate the ventrocaudal nucleus (Vc). This remains to be robustly validated or assessed as a method to guide surgical targeting. The authors assessed the validity of connectivity-based parcellation for targeting the Vc and its potential for improving clinical outcomes of pain surgery. METHODS A cohort of 19 patients with regional, chronic neuropathic pain underwent preoperative structural and diffusion MRI, then progressed to deep brain stimulation targeting the Vc based on traditional atlas coordinates. Surgical thalami were retrospectively segmented and then parcellated based on tractography estimates of thalamocortical connectivity. The location of each patient’s electrode array was analyzed with respect to their primary somatosensory cortex (S1) parcel and compared across patients with reference to the thalamic homunculus. RESULTS Ten patients achieved long-term pain relief. Sixty-one percent of an average array (interquartile range 42%–74%) was located in the S1 parcel. In patients who achieved long-term benefit from surgery, array location in the individually generated S1 parcels was medial for face pain, centromedial for arm pain, and centrolateral for leg pain. Patients who did not benefit from surgery did not follow this pattern. Standard stereotactic coordinates of electrode locations diverged from this pattern. CONCLUSIONS Connectivity-based parcellation of the thalamus appears to be a reliable method for segmenting the Vc. Identifying the Vc in this way, and targeting mediolaterally as appropriate for the region of pain, merits exploration in an effort to increase the yield of successful surgical procedures.

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Issues on the Use of White Blood Cell Growth Factors in Oncology Practice

American Society of Clinical Oncology Educational Book ◽

10.1200/edbk_156064 ◽

2016 ◽

pp. e528-e532

Author(s):

Gary H. Lyman

Keyword(s):

Risk Factors ◽

Overall Survival ◽

Growth Factors ◽

Cell Growth ◽

Blood Cell ◽

White Blood Cell ◽

Patient Specific ◽

Appropriate Use ◽

Disease Free

Appropriate use of myeloid growth factors may reduce the risk of neutropenic complications including febrile neutropenia (FN) in patients receiving cancer chemotherapy. The recently updated American Society of Clinical Oncology (ASCO) Guidelines on the Use of the White Blood Cell Growth Factors recommends routine prophylaxis with these agents starting in the first cycle when the risk of FN is 20% or greater. However, the risks for neutropenic complications and the risk of serious adverse consequences from FN vary considerably with different chemotherapy regimens as well as other disease-, treatment-, and patient-specific risk factors. Considerably more information is now available on the major risk factors for FN. Multivariable risk models combining factors look promising but require further validation. Most clinical studies of myeloid growth factor prophylaxis assessed relative risk (RR) of FN but were not powered to evaluate the effect of prophylaxis on disease-free or overall survival. Accumulating evidence suggests, however, that the appropriate use of these agents in selected patients may improve both short-term and long-term survival by reducing the immediate risk of mortality accompanying patients with high-risk disease developing FN as well as improving disease-free and overall survival by enabling the delivery of full dose intensity chemotherapy and reducing the risk of disease recurrence in patients treated with curative intent. Further studies to evaluate risk factors and models for FN are needed to guide clinical and shared decision making for the optimal personalized use of these agents and offer patients at increased risk the best chance of long-term disease control.

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Impact of patient-specific factors and spinopelvic alignment on the development of adjacent segment degeneration after short-segment lumbar fusion

10.21203/rs.3.rs-898513/v1 ◽

2021 ◽

Author(s):

László Kiss ◽

Zsolt Szövérfi ◽

Ferenc Bereczki ◽

Péter Endre Éltes ◽

Balázs Szöllösi ◽

...

Keyword(s):

Disc Degeneration ◽

Lumbar Fusion ◽

Adjacent Segment Degeneration ◽

Patient Specific ◽

Adjacent Segment ◽

Short Segment ◽

Adjacent Disc ◽

Disc Bulge ◽

Specific Factors

Abstract Objectives: The main purpose of the study was to analyse the different demographical, morphological, and surgery-related parameters influencing the development or progress of degeneration in adjacent segments after routine, short-segment lumbar fusions.Summary of Background data: Adjacent segment degeneration (ASD) considered as a major long-term complication after lumbar fusions. Possible risk factors are related to the patients’ demographics, spinopelvic anatomy or preoperative lumbar intervertebral disc conditions. The current literature lacks of well-designed prospective studies focusing on the multidimensional nature of the condition.Methods: A prospective cohort of 100 patients who underwent one- or two-level lumbar transforaminal interbody fusions due to lumbar degenerative pathology was conducted. Demographical, radiological findings (spinopelvic parameters, adjacent segmental radiological as well as magnetic resonance imaging (MRI) features) and long-term outcome data (5-year) were analysed to identify factors associated with ASD. Results: ASD patients showed higher level of pain (p=0.004) and disability (p=0.020) at follow-up. In univariate analysis, older age, upper-level lumbar fusion (p=0.007), lower L4-S1 lordosis (p=0.039), PI-LL mismatch (p=0.021), Pfirrmann grade III or higher disc degeneration (p=0.002) and the presence of disc bulge/herniation were (p=0.007) associated with ASD. Final result of multivariate analysis showed major degenerative sign (disc degeneration and/or disc bulge) as a risk factor (OR 3.85, CI 1.43-10.37, p=0.006).Conclusion: By examining the role of different patient- and procedure-specific factors, we found that preoperative major degenerative signs at the adjacent segment increase the risk of ASD causing significantly worse outcome after short-segment lumbar fusion. Adjacent disc conditions should be considered carefully during surgical planning.

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