THE EFFECT OF THE SARS-COV-2 PANDEMIC ON THE INCIDENCE OF PSYCHIATRIC DISORDERS: AN OVERVIEW.

The SARS-CoV-2 pandemic exerted an unprecedented threat to the population worldwide. This led to a sharp increase in symptoms of depression, anxiety, and PTSD, especially in the early phase of the pandemic. As far as data allowed a comparison with the pre-pandemic era, an increase by odds ratios of up to 3,5 was found. People affected by the virus showed an even greater amount of symptomatology as compared to the general population. Next to psychological stress, direct and indirect effects of the virus on the brain in these persons could be observed. Only on very few occasions, a direct invasion of the virus in the brain could be observed. Yet far more important seems to be the induction of a low-grade inflammation in the brain ("neuroinflammation"). This kind of processes have been observed earlier accompanying many psychiatric and neurologic diseases. In this way, especially cognitive symptoms might persist long after the acute infection has abated.

Electromechanical Reciprocity Applied to the Sensing Properties of Guided Elastic Wave Transducers.

Guided elastic wave (GEW) transducers for structural health monitoring (SHM) can act as transmitters (senders) and receivers (sensors). Their performance in both cases depends on the structure to which they are coupled. Therefore, they must be characterized as system transducer- structure. The characterization of the transducer-structure as transmitter using a Scanning Laser Doppler Vibrometer (SLDV) is straightforward, whereas its characterization as receiver is non-trivial. We propose to exploit electromechanical reciprocity, which is an identity between the transfer functions of electrical-to-mechanical and mechanical-to-electrical conversions. For this purpose, the well-known electromechanical reciprocity theorem was adapted to the following situation: The two reciprocal states are "electrical excitation and detection of the surface velocity at point P" and "mechanical excitation at P and measurement of the electrical quantities". According to the derived formulas, the quantities on the mechanical and electrical sides must be chosen appropriately to ensure reciprocity as well as that the corresponding transfer functions are equal. We demonstrate the reciprocity with experimental data for correctly chosen transfer functions and show the deviation in reciprocity for a different choice. Furthermore, we propose further applications of electromechanical reciprocity.

First-episode psychotic disorders in the wake of the COVID-19 pandemic: a descriptive review of casereports.

OBJECTIVE: Since the onset of COVID-19 pandemic, many case reports and case series dealt with new-onset psychotic disorders in patients either infected with SARS-CoV-2 or thematically linked to the pandemic, but without an infection. Our aim was to provide a comprehensive collection of these reports to illustrate the nature of these psychoses. METHODS: We conducted a literature search in MEDLINE, Embase, PsycINFO, using search terms regarding first-episode psychotic disorders in the context of corona. RESULTS: 96 case reports or case series covering 146 patients (62 without and 84 with SARS-CoV-2 infection) were found. Compared to patients without infection, patients with infection showed significantly more often visual hallucinations (28.6% vs 8.1%), confusion (36.9% vs 11.3%), an acute onset of illness (88.5% vs 59.6%) and less often depression (13.1% vs 35.5%) and a delusional content related to the pandemic (29.5% vs 78.3%). Both groups had an equally favourable outcome with a duration of psychosis ≤2 weeks in half and full remission in two-thirds of patients. In patients with infection, signs of inflammation were reported in 78.3% and increased CRP in 58.6%. While reports on patients with infection are continuously published, no report about patients without infection was found after July 2020. CONCLUSION: Cases without infection were considered reactive and originated all from the first wave of the corona pandemic. In cases with infection, inflammation was considered as the main pathogenetic factor but was not found in all patients. Diagnosis was impeded by the overlap of psychosis with delirium.

[Neuropsychiatric Aspects of COVID-19 - A Narrative Overview]. / Neuropsychiatrische Aspekte von COVID-19 ­ Eine narrative Übersicht.

The SARS-CoV-2 virus (Severe Acute Respiratory Syndrome Coronavirus Type 2) and COVID-19 (Coronavirus Disease 2019) can affect numerous organ systems. In the present paper we offer an overview of the current state of knowledge about the psychiatric aspects of SARS-CoV-2 infection.Medline, Embase und LIVIVO were searched for relevant literature, the last query dating from March 2nd, 2021. Different stress factors in the context of the pandemic can lead to manifest mental illnesses. In addition, there is a risk of neuropsychological changes due to the biological effects of the virus itself.Our work describes the psychological symptoms of COVID-19 sufferers themselves and the psychological effects of the epidemic and the associated socio-economic and psychosocial stress factors on those who are not sick.The most common psychiatric complication among people with COVID-19 is delirium, while hospitalized patients seem to have an increased incidence of symptoms of anxiety, depression and PTSD. There are many case reports on psychotic disorders. In general, an existing psychiatric illness (especially dementia and psychotic disorders) also increases the risk of infection and of a more severe course of the disease. After recovery from COVID-19 infection, there is also a higher incidence of mental illnesses, in particular "Chronic Post-SARS Syndrome" with its manifestations such as fatigue, anxiety, depression and PTSD. In addition, the course of dementia seems to be negatively influenced by an infection with SARS-CoV-2.The second part deals with the effects of the epidemic as a stressor and the established socio-political measures on the mental health of people with and without previous mental illnesses. The literature currently available shows high symptom values for anxiety and depressive disorders as well as post-traumatic stress disorders, stress, suicidality, sleep disorders etc. Risk factors seem to include female gender, younger age and fewer resources, as well as previous psychiatric or physical illnesses. Extrinsic factors such as high infection rates, large numbers of deaths, long curfews/lockdowns, low trust in the government and ineffective measures against economic and social consequences increase the burden.

Intraoperative findings, complications, and short-term results after lumbar microdiscectomy with or without implantation of annular closure device.

BACKGROUND: Standard microscopic lumbar discectomy (MLD) is a short operation with minimal blood loss, and a low rate of peri- and intraoperative complications. The objective of this study was to evaluate intraoperative findings, complications, and early postoperative neurological outcome (< 105 days) in patients undergoing MLD with or without implantation of an annular closure device (ACD). METHODS: This study is based on data analysis of a post-marketing, prospective, multicenter RCT in Europe including patients undergoing standard MLD with or without implantation of an ACD (Barricaid®, Intrinsic Therapeutics, Inc., Woburn, MA). Enrollment of 554 patients in 21 centers in Europe (Germany, Switzerland, Austria, Belgium, The Netherlands, and France) started in 2010 and was completed in October 2014, with 276 patients randomized to the ACD group and 278 to the control group. RESULTS: Mean operation time was 70 min in the ACD group and 52 min in the control group (p < 0.0001). Intraoperative fluoroscopy time was 24 s in the ACD group and 7 s in the control group (p < 0.0001). Average blood loss was 94.2 ml in the ACD group and 64.7 ml in the control group (p = 0.0001). Serious device- or procedure-related adverse events occurred in 3.7% (10/272) of the ACD group and 7.9% (22/278) of the control group. Dural injuries occurred in 13 (4.8%) patients in the ACD group and 7 (2.5%) in the control group. There was one device-related nerve root injury resulting in a nerve root amputation. Surgical complications included 3 hematomas in the ACD group and 4 in the control group; 3 infections occurred in both groups. Device migrations were documented in 3 patients in the ACD group. Patients in the ACD group (n = 7, 2.6%) underwent fewer reoperations compared with that in the control group (n = 16, 5.8%, OR = 2.3 (0.9-5.7)). Mean VAS leg pain at 3 months was 11.9 in the ACD and 15.1 in the control group, respectively. CONCLUSION: Short-term outcome after MLD with or without implantation of ACD was similar in both groups. Patients included in the ACD group underwent fewer reoperations in the first 3 months after surgery. Nevertheless, longer operation time, higher amount of blood loss, and risk of nerve root lesion during device implantation should be considered additional risks in patients undergoing ACD implantation after MLD.

Serotonin 1A receptor density measured by F18-Mefway PET/CT in mesiotemporal cortex and raphe does not discriminate therapeutic response in patients with major depressive episode.

BACKGROUND: More than 50% of patients with major depressive episode (MDE) fail to respond to initial treatment with first line pharmacological therapy. Altered receptor and serotonin transporter function are considered to be associated with mental disorders. Our investigation aimed on the density of the HT1A receptor in mesiotemporal cortex (MTC) and raphe measured by F18-Mefway in patients with MDD. METHODS: Patients with untreated clinically suspected major depressive episode were recruited from June 2012 to May 2014. 49 patients were included into the study: 36 patients (73%) were identified as responders, whereas 13 (27%) were non-responders. Gender distribution was 26 men (56%) and 23 women (44%). For treatment, only a standard medication of a selective serotonin reuptake inhibitor (SSRI) with escitalopram in a range of 10-20 mg/day was permitted. Responders were defined by improvement of the MADRS>50%. Visually MTC had the highest uptake of F18-Mefway among all brain regions, an asymmetry could not be observed in any patient. An elliptical region was drawn over the amygdala and hippocampus area and a small circular region was drawn over the raphe nuclei. All data were calculated related to (unspecific) cerebellar uptake. RESULTS: The quotient of the right MTC was 5.00 [4.33; 5.50] in all patients, in responders 5.00 [4.00; 5.75] and in non-responders 5.00 [4.50; 5.50] (P=0.56). The quotient of the left MTC presented with a median level of 4.50 [4.50; 5.50] in all persons. The responders had 4.50 [4.50; 5.75] which was not statistically significant to the data of the non-responders with 5.00 [4.50; 5.50] at P=0.64. The raphe had a median quotient of 2.50 [2.00; 3.00] in all and the cohort of responders, whereas non-responders had 2.50 [2.00; 2.50] (P=0.61). Also the absolute values of SUV in the three brain regions were not statistically different between the cohorts. Additionally, we did not find any sex-related differences in our patient group. CONCLUSIONS: Serotonin 1A receptor density can be assessed efficiently by F18-Mefway and PET-CT in patients with MDE. The method can be estimated as a possible tool for clinical and academic investigation, marked tracer uptake can constantly be observed at MTC and the raphe. Anyhow, under conditions of real life in patient care, it is not possible to distinguish patients with a good prognosis who will respond to standard SSRI therapy from non-responders who would benefit from a different therapeutic approach starting earlier.

New insights into the natural course and clinical relevance of Modic changes over 2 years following lumbar limited discectomy: analysis of prospective collected data.

PURPOSE: Few retrospective studies have addressed Modic changes (MC) following lumbar spine surgery, though it is usually assumed that MC increase in grade and incidence. To test this conventional wisdom, we investigated the natural course of MC following primary lumbar limited discectomy with two-year follow-up. In addition, a possible clinical relevance to those changes was assessed. METHODS: The data of the control group (278 subjects) of a prospective randomized, controlled trial (RCT) were evaluated retrospectively. RESULTS: We did not observe a simple increase in MC with regard to grade. There is variable activity observed in Type 2 (at 12 months) and in Type 1 (at 24 months). Conversion from one grade to another may occur and may be upward or downward. The incidence of MC increased slightly over time, as after surgery a decreasing percentage of the study group remained without MC over two years (1 year: 34% (85/250); 2 years: 30% (72/237)). Radiological parameters (rotation, translation, and spondylolisthesis) had no significant correlation to MC or MC subtypes. Lastly, we found that neither the different MC types nor their changes were correlated with clinical parameters (VAS back, VAS leg, ODI score) preoperatively or during follow-up. CONCLUSION: The pattern of Modic changes following lumbar limited discectomy is complex, not simply increasing. There is variable activity in MC Types 1 and 2 at the different time points of follow-up, and conversion from a higher grader to a lower one or vice versa is possible. These slides can be retrieved under Electronic Supplementary Material.

Red blood cell transfusion probability and associated costs in neurosurgical procedures.

BACKGROUND: The extent of red blood cell units (RBC) needed for different neurosurgical procedures and the time point of their administration are widely unknown, which results in generously cross-matching prior to surgery. However, RBC are increasingly requested in the aging western populations, and blood donations are significantly reduced. Therefore, the knowledge of the extent and time point of administration of RBC is of major importance. METHODS: This is a retrospective single center analysis. The incidence of RBC transfusion during surgery or within 48 h after surgery was analyzed for all neurosurgical patients within 3 years. Costs for cross-matched and transfused RBC were calculated and risk factors for RBC transfusion analyzed. RESULTS: The risk of intraoperative RBC administration was low for spinal and intracranial tumor resections (1.87%) and exceeded 10% only in spinal fusion procedures. This was dependent on the number of fused segments with an intraoperative transfusion risk of > 12.5% with fusion of more than three levels. Multiple logistic regression analysis showed a significantly increased risk for RBC transfusion for female gender (p = 0.006; OR 1.655), higher age (N = 4812; p < 0.0001; OR 1.028), and number of fused segments (N = 737; p < 0.0001; OR 1.433). Annual costs for cross-matching were 783,820.88 USD and for intraoperative RBC administration 121,322.13 USD. CONCLUSIONS: Neurosurgical procedures are associated with a low number of RBC needed intraoperatively. Only elective spine fusion procedures with ≥ 3 levels involved and AVM resections seem to require cross-matching of RBC. The present data may allow changing the preoperative algorithm of RBC cross-matching in neurosurgical procedures and help to save resources and costs.

Endplate changes after lumbar discectomy with and without implantation of an annular closure device.

BACKGROUND: The implantation of a bone-anchored annular closure device (ACD) might be associated with the developed new endplate changes (EPC) after surgery. METHODS: A post hoc analysis has been done in patients from a prospective randomized multicenter study. All patients underwent limited lumbar discectomy with intraoperative randomization into the groups limited lumbar discectomy alone or additional ACD implantation. Low-dose lumbar computed tomography (CT) and clinical investigations were performed preoperatively and 12 months after the operation. RESULTS: A total of 554 patients were randomized. After exclusion of dropouts, the per-protocol population included 493 patients (251 in the control group and 242 in the ACD group); the follow-up rate was ≥ 90%. The number of patients showing EPC at baseline was similar in both groups. The number of patients showing EPC and the total EPC lesion area significantly increased in both groups over time, but significantly increased more in the EPC group for the superior and inferior endplate (all P < 0.0001). There was no association of pre-existing number and size of EPC with sex, age, or smoking habits. Correlation of clinical variables showed no relation with number, size, and increase of EPC area after surgery. CONCLUSIONS: Patients with primary lumbar disc herniation show EPC in the corresponding segments. There is a significant increase of lesion number and size within 12 months after discectomy. This increase is significantly more pronounced in the ACD group. Presence and growth of EPC is not correlated with low-back pain or ODI.

Reliability and scientific use of a surgical planning software for anterior cervical discectomy and fusion (ACDF).

PURPOSE: Software-based planning of a spinal implant inheres in the promise of precision and superior results. The purpose of the study was to analyze the measurement reliability, prognostic value, and scientific use of a surgical planning software in patients receiving anterior cervical discectomy and fusion (ACDF). METHODS: Lateral neutral, flexion, and extension radiographs of patients receiving tailored cages as suggested by the planning software were available for analysis. Differences of vertebral wedging angles and segmental height of all cervical segments were determined at different timepoints using intraclass correlation coefficients (ICC). Cervical lordosis (C2/C7), segmental heights, global, and segmental range of motion (ROM) were determined at different timepoints. Clinical and radiological variables were correlated 12 months after surgery. RESULTS: 282 radiographs of 35 patients with a mean age of 53.1 ± 12.0 years were analyzed. Measurement of segmental height was highly accurate with an ICC near to 1, but angle measurements showed low ICC values. Likewise, the ICCs of the prognosticated values were low. Postoperatively, there was a significant decrease of segmental height (p < 0.0001) and loss of C2/C7 ROM (p = 0.036). ROM of unfused segments also significantly decreased (p = 0.016). High NDI was associated with low subsidence rates. CONCLUSIONS: The surgical planning software showed high accuracy in the measurement of height differences and lower accuracy values with angle measurements. Both the prognosticated height and angle values were arbitrary. Global ROM, ROM of the fused and intact segments, is restricted after ACDF.

Core herniation after implantation of a cervical artificial disc: case report.

INTRODUCTION: Cervical artificial discs (CADs) represent an established surgical option in selected patients with cervical spinal disc degeneration. Though CADs have been available for many years, there is a lack of information concerning long-term safety, durability and implant-related failure rates. MATERIALS AND METHODS: The authors describe the failure of a M6-C CAD (Spinal Kinetics, Sunnyvale, CA, USA). RESULTS: Eight years after implantation of a CAD of the M6 type, a 39-year-old female presented with new clinical signs of cervical myelopathy. Radiologically, medullar compression due to posterior core herniation was the suspected cause. The damaged CAD was removed and the segment fused. During revision surgery, rupture of the posterior structures could be detected. Possible mechanisms leading to implant failure are discussed. CONCLUSION: As there is no standard regarding clinical and radiological follow-up for patients with CADs, radiological long-term follow-up investigations seem to be justified for exclusion of implant failure.

Influence of cervical bone mineral density on cage subsidence in patients following stand-alone anterior cervical discectomy and fusion.

PURPOSE: Anterior cervical discectomy and fusion (ACDF) is a common procedure for the treatment of cervical degenerative diseases. However, cage subsidence remains a frequent problem. We therefore investigated if cage design and site-specific bone mineral density (BMD) contribute to the rate and direction of subsidence following ACDF. METHODS: Patients were prospectively included and received two different cages (groups 1 and 2) using minimization randomization. The degree and direction of cage subsidence were determined using plain radiographs. Neck pain intensity on the visual analogue scale (VAS), the neck disability index (NDI), and the patient satisfaction index were recorded up to 12 months after surgery. RESULTS: 88 patients were analysed with a mean age of 53.7 ± 11.8 years. BMD values decreased in craniocaudal direction from 302.0 ± 62.2 to 235.5 ± 38.9 mg/cm(3). Both groups showed significant height gain after the operation (both p < 0.001), followed by height loss at 3 months (both p < 0.05) and at 3-12 months after the operation (both p > 0.05). Both groups showed improvement of VAS neck pain intensity (both p < 0.05) and NDI (both p < 0.05). The direction of cage subsidence was similar, no correlations were found between cage subsidence and BMD or various clinical parameters. CONCLUSIONS: Implant geometry of both cages and variations of the operative procedure promoted a relatively high degree of cage subsidence. Further studies are necessary to identify a relation of BMD and subsidence using optimized implant geometry and by controlling additional intraoperative variables.

Dynamic Autoregulatory Response After Aneurysmal Subarachnoid Hemorrhage and Its Relation to Angiographic Vasospasm and Clinical Outcome.

BACKGROUND: Impaired cerebral autoregulation (CA) is increasingly recognized to contribute to sequelae after aneurysmal subarachnoid hemorrhage (SAH). The current study characterizes the course of the dynamic autoregulation index (ARI) during the first 8 days after SAH and its coherence with angiographic vasospasm (VS) and clinical outcome. METHODS: Fifty-one patients with SAH were prospectively included within 48 h after the ictus. The ARI was determined daily for each hemisphere with the thigh cuff test. The degree of cerebral VS was evaluated based on a baseline digital subtraction angiography (DSA) after the ictus and a follow-up DSA on day 8. The clinical outcome was determined by the Modified Rankin Scale (mRS), the Glasgow Outcome Scale Extended (GOSE), and the National Institute of Health Stroke Scale (NIHSS) at discharge from the intensive care unit. RESULTS: Impaired CA significantly correlated with unfavorable clinical outcome scores (mRS, p = 0.0021; GOSE, p = 0.0027; NIHSS, p = 0.0091). ARI-values of patients with a favorable clinical outcome (mRS 0-3) showed a significant improvement during the first 8 days (+0.1964/day; p = 0.0148) compared to a significant decrease of ARI-values in patients with an unfavorable clinical outcome (-0.2976/day; p = 0.0182). The degree of CA impairment significantly correlated with the severity of VS in the middle cerebral artery (p = 0.0184). CONCLUSIONS: Early deterioration of CA significantly correlates with unfavorable clinical outcome and severity of angiographic vasospasm. Dynamic CA measurements might represent an important tool in stratifying therapy guidelines in patients after SAH.

Clinical relevance of neuroforaminal patency after anterior cervical discectomy and fusion.

BACKGROUND: We sought to investigate the clinical relevance of neuroforaminal patency and facet degeneration one year after anterior cervical discectomy and fusion (ACDF). Previous studies were characterized by imprecise techniques and fragmentary measurements, and most lacked reliable clinical data and correlation analyses. METHODS: Patients with cervical mono- or bi-level degenerative pathology were prospectively included. Neuroforaminal size and segmental height were determined quantitatively, and the degree of facet degeneration was assessed qualitatively before and one year after the operation, by computed tomography. Clinical data, such as the severity of neck and arm pain, were assessed on a visual analogue scale (VAS) from 0 to 10, and neck disability index (NDI) was recorded before and one year after the operation. Their correlation with radiological data was investigated. RESULTS: Seventy-nine patients aged 53.3 ± 11.3 years were included. One year after surgery, median VAS pain intensity was still significantly improved (neck, from 5 to 1; right arm, from 2 to 1; left arm, from 4 to 1) as was NDI (from 40 to 20). Neuroforaminal size showed a reduction on both sides (left, 0.0289 ± 0.09 cm(2); right, 0.0149 ± 0.08 cm(2)). One year after the operation, segmental height decreased and facet degeneration increased from measures taken before the operation. No correlations were found between neuroforaminal stenosis or the degree of facet degeneration and various clinical outcome parameters. CONCLUSIONS: The decrease in segmental height one year after ACDF leads in turn to secondary neuroforaminal stenosis and progressive facet degeneration. Of the various neuroforaminal variables used, none revealed a threshold value indicative of the presence or severity of radicular arm pain. This absence of correlation between imaging and clinical information is important and should be considered when allocating patients for surgical interventions.

[Interaction of somatic findings and psychiatric symptoms in COVID-19. A scoping review]. / Interaktion von körperlichen Veränderungen und psychischen Störungen bei COVID-19. Ein Scoping Review.

An infection with SARS-CoV­2 can affect the central nervous system, leading to neurological as well as psychiatric symptoms. In this respect, mechanisms of inflammation seem to be of much greater importance than the virus itself. This paper deals with the possible contributions of organic changes to psychiatric symptomatology and deals especially with delirium, cognitive symptoms, depression, anxiety, posttraumatic stress disorder and psychosis. Processes of neuroinflammation with infection of capillary endothelial cells and activation of microglia and astrocytes releasing high amounts of cytokines seem to be of key importance in all kinds of disturbances. They can lead to damage in grey and white matter, impairment of cerebral metabolism and loss of connectivity. Such neuroimmunological processes have been described as a organic basis for many psychiatric disorders, as affective disorders, psychoses and dementia. As the activation of the glia cells can persist for a long time after the offending agent has been cleared, this can contribute to long term sequalae of the infection.

The high-risk discectomy patient: prevention of reherniation in patients with large anular defects using an anular closure device.

PURPOSE: With lumbar discectomy for disc herniation, surgeons must choose between limited nucleus removal associated with higher reherniation risk or more aggressive nucleus removal associated with increased back pain and disc degeneration. This trade-off is particularly challenging in patients with large anular defects, which carry the highest risk of reherniation. We examined the effect of an anular closure device on reherniation and clinical outcomes. METHODS: Seventy-five primary discectomy patients had a limited discectomy followed by implantation of an anular closure device and were followed-up to 2 years. Anular defect size and volume of removed nucleus was recorded at surgery. Reherniations were reported, pain and function were monitored throughout, and imaging was performed at annual visits. RESULTS: The overall symptomatic reherniation rate was 1.4%, and the asymptomatic reherniation rate was 1.5% at 12 months and 5.1% at 24 months. Both rates compare favorably with literature reports which include symptomatic rates ranging between 2 and 18% (up to 27% for patients with large anular defects) and an asymptomatic rate of 13%. CONCLUSIONS: The low reherniation rate in patients at high-risk of reherniation based on anular defect size, despite discectomy being only limited, suggests that an anular closure device may reduce reherniation risk. Clinical outcomes for pain and function at 1 and 2 years post-operatively compared favorably with literature reports. Further study in a randomized controlled trial is required to confirm these results.

Unique Device Identification-Based Linkage of Hierarchically Accessible Data Domains in Prospective Surgical Hospital Data Ecosystems: User-Centered Design Approach.

BACKGROUND: The electronic health record (EHR) targets systematized collection of patient-specific, electronically stored health data. The EHR is an evolving concept driven by ongoing developments and open or unclear legal issues concerning medical technologies, cross-domain data integration, and unclear access roles. Consequently, an interdisciplinary discourse based on representative pilot scenarios is required to connect previously unconnected domains. OBJECTIVE: We address cross-domain data integration including access control using the specific example of a unique device identification (UDI)-expanded hip implant. In fact, the integration of technical focus data into the hospital information system (HIS) is considered based on surgically relevant information. Moreover, the acquisition of social focus data based on mobile health (mHealth) is addressed, covering data integration and networking with therapeutic intervention and acute diagnostics data. METHODS: In addition to the additive manufacturing of a hip implant with the integration of a UDI, we built a database that combines database technology and a wrapper layer known from extract, transform, load systems and brings it into a SQL database, WEB application programming interface (API) layer (back end), interface layer (rest API), and front end. It also provides semantic integration through connection mechanisms between data elements. RESULTS: A hip implant is approached by design, production, and verification while linking operation-relevant specifics like implant-bone fit by merging patient-specific image material (computed tomography, magnetic resonance imaging, or a biomodel) and the digital implant twin for well-founded selection pairing. This decision-facilitating linkage, which improves surgical planning, relates to patient-specific postoperative influencing factors during the healing phase. A unique product identification approach is presented, allowing a postoperative read-out with state-of-the-art hospital technology while enabling future access scenarios for patient and implant data. The latter was considered from the manufacturing perspective using the process manufacturing chain for a (patient-specific) implant to identify quality-relevant data for later access. In addition, sensor concepts were identified to use to monitor the patient-implant interaction during the healing phase using wearables, for example. A data aggregation and integration concept for heterogeneous data sources from the considered focus domains is also presented. Finally, a hierarchical data access concept is shown, protecting sensitive patient data from misuse using existing scenarios. CONCLUSIONS: Personalized medicine requires cross-domain linkage of data, which, in turn, require an appropriate data infrastructure and adequate hierarchical data access solutions in a shared and federated data space. The hip implant is used as an example for the usefulness of cross-domain data linkage since it bundles social, medical, and technical aspects of the implantation. It is necessary to open existing databases using interfaces for secure integration of data from end devices and to assure availability through suitable access models while guaranteeing long-term, independent data persistence. A suitable strategy requires the combination of technical solutions from the areas of identity and trust, federated data storage, cryptographic procedures, and software engineering as well as organizational changes.

Correlation of clinical outcome and angiographic vasospasm with the dynamic autoregulatory response after aneurysmal subarachnoid hemorrhage.

BACKGROUND: A certain correlation between unfavorable clinical outcome, incidence of vasospasm, and impaired pressure autoregulation in patients following aneurysmal subarachnoid hemorrhage (aSAH) has been suggested. However, determination of vasospasm is inaccurate and the measurement technique of cerebral vasoreactivity seems not to have been sufficiently validated. Therefore, a correlation of clinical outcome and the extent of angiographic VS was performed using an established autoregulation test. MATERIAL AND METHODS: Proximal and global angiographic vasospasm (pVS, gVS) were determined in bilateral M1 segments. Dynamic tests of pressure autoregulation were performed 1 day before and after, and on the day of angiography using Aaslid's thigh leg cuff test. Patient outcome was assessed using the Extended Glasgow Outcome Scale (GOSE). KEY RESULTS: Complete datasets were available for 22 patients. Mean autoregulatory indices (ARI) around the day of angiography were 3.9 ± 2.3. Proximal mean reduction of vessel diameter was -23.3% ± 9.1%. Global vasospasm was not present in 10 hemispheres, mild in 15, moderate in 15, and severe in 4. Hemispheric ARI values and angiographic data showed a significant correlation (pVS -0.382, p = 0.015; gVS -0.477, p = 0.002). The degree of angiographic vasospasm and low ARI values correlated significantly with an unfavorable outcome (0.677, p = 0.001). CONCLUSION: Incidence of angiographic vasospasm and impaired clinical outcome seems to be related to impaired pressure autoregulation following aSAH.

Nicardipine pellets for the prevention of cerebral vasospasm.

Regardless of numerous efforts there is no prophylactic treatment proven to be effective in the prevention of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH). As systemic administration of vasoactive drugs has been associated with significant side effects and insufficient efficacy, intrathecal administration of nicardipine prolonged-release implants (NPRI) has been developed. At the time of surgical clipping of the ruptured aneurysm, NPRIs are positioned next to the large cerebral arteries. Several clinical protocols revealed that NPRIs dramatically reduce the incidence and severity of angiographic vasospasm, which was paralled by a reduction in cerebral infarction and delayed ischemic neurologic deficit. On average, the incidence of angiographic vasospasm decreased from approximately 70% to less than 10%. Efficacy seemed to be dose-dependent and reduced for peripheral vasospasm. Nevertheless, a significant improvement of functional outcome was demonstrated. A separate patient series demonstrated the efficacy of fewer NPRIs in the perichiasmatic cistern. Further investigations were performed in comparison to coiled patients and with intraventricular implantation of NPRIs, which had a less pronounced effect. Overall, NPRIs are a most promising option for the prevention of cerebral vasospasm after SAH and large controlled trials are needed to further confirm these results.