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1.
Curr Med Sci ; 42(6): 1131-1139, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36542326

RESUMO

OBJECTIVE: Pituitary adenomas (PAs) can adapt an aggressive phenotype by invading adjacent brain structures with rapid cellular proliferation. Previous studies demonstrated that excessive expression of metalloproteases ADAM12 and MMP-14 is instrumental for the active proliferation and invasiveness of PA cells in vitro and of tumors in vivo. However, the mechanisms regulating ADAM12 and MMP-14 expression in PAs remain unclear. METHODS: Target gene prediction and transcriptomic profiling of invasive vs. noninvasive human PA samples were performed to identify miRNA species potentially involved in the regulation of ADAM12 and MMP14. For cellular analyses of miRNA functions, two mouse PA cell lines (AtT20 and TtT/GF) were transfected with miR-149-3p and miR-149-5p, respectively. The effects of miR-149 (3p and 5p) on expression levels of ADAM12 and MMP14 were determined by Western blotting followed by an analysis of proliferation and colony formation assays, scratch migration assays, and invasion assays. RESULTS: A significant downregulation of miRNA-149 was observed in invasive vs. noninvasive PA (0.32 vs. 0.09, P<0.0001). In AtT-20 and TtT/GF mouse PAs cells, transfection of mimic miRNA-149 (3p and 5p) caused a significantly reduced cell proliferation and matrigel invasion, whilst the effect on cell migration was less pronounced. Both strands of miRNA-149 (3p and 5p) markedly reduced protein levels of ADAM12 and MMP-14 by at least 40% in both cell lines. CONCLUSION: This study proved that the invasiveness of PA cells is, at least partly, regulated by miRNA-149-dependent expression of ADAM12 and MMP-14.


Assuntos
MicroRNAs , Neoplasias Hipofisárias , Camundongos , Animais , Humanos , Neoplasias Hipofisárias/genética , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Movimento Celular/genética , Proteína ADAM12/genética , Proteína ADAM12/metabolismo
2.
Healthcare (Basel) ; 10(8)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35893198

RESUMO

Objective: At the beginning of 2020, the COVID-19 pandemic enforced a rapid reallocation of healthcare resources. Our neurosurgical department is located in the German county of Marburg−Biedenkopf, about 80 km from the nearest major city. We were able to maintain our previously established open-door policy after the emergence of COVID-19. Here, we report on dynamics in the catchment area for neurotrauma patients at our department during the pandemic. Methods: 763 consecutive neurotrauma cases admitted to our department between 1 January 2018 and 31 December 2021 were analyzed retrospectively. Patients' age, gender, origin, diagnoses, and outcomes were recorded. The number of patients hospitalized with a COVID-19 infection in Germany (PHCG) were retrieved from the Robert Koch Institute (RKI). We defined calendar weeks with >1000 PHCG as high COVID-19 caseload weeks (HCLW). Chi-square and Fisher's exact served as statistical tests. Results: In 2020 and 2021, we observed a significantly increased number of neurotrauma patients who, with primary residence outside of our district, were admitted to our hospital compared to 2018 and 2019 (p < 0.001), while there were no significant differences in in-house mortality. During HCLW, a significantly increased number of neurotrauma patients with primary residence in the densely populated southwestern margin (SWM) of the contiguous part of our catchment area were referred to us compared to the time prior to the pandemic and between HCLW (p = 0.003). In neurotrauma patients admitted from the SWM during HCLW, there was no tendency towards higher in-house mortality. Conclusion: An open-door policy may moderate the risk of involuntarily triaging neurotrauma patients during a pandemic.

3.
Healthcare (Basel) ; 9(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34574915

RESUMO

BACKGROUND: The coronavirus 2019 (COVID-19) pandemic forced students and teachers to rapidly adopt digital education methods. Proper guidance for and refinement of such methods is continuously required. Here, we report on the educational experience students and academic staff at the neurosurgical department of a German university hospital made with digital teaching modules (DTMs) that were newly developed due to the transition to digital teaching during the first year of the COVID-19 pandemic and on the insights gained therefrom. METHODS: Nine newly created DTMs provided students the option to anonymously evaluate each module by assigning a score from 0 (worst value) to 5 (best value) to it. Access count, evaluation count, average evaluation, number of included (interactive) figures, number of presented cases, number of linked publications, and number of included multiple-choice questions for each DTM were recorded retrospectively. For each DTM, we aimed to correlate access count, evaluation count, and average evaluation with the number of included (interactive) figures, number of presented cases, number of linked publications, and number of included multiple-choice questions. E-mail responses from individual students as to the DTMs were collected. Among students, an anonymous, voluntary online survey regarding the DTMs was conducted. RESULTS: Number of figures and average evaluation per DTM were significantly positively correlated (Spearman's rho = 0.85; p = 0.0037). Number of figures and number of evaluations per DTM were also significantly positively correlated (Spearman's rho = 0.78; p = 0.0137). Responses from individual students indicated that illustrative cases and interactive figures might further increase DTM popularity. CONCLUSION: As a valuable adjunct in medical student education, DTMs should contain (interactive) figures, illustrative cases, a scoring option, and the option to give individual feedback towards the academic staff.

4.
J Neurosurg Anesthesiol ; 33(1): 10-20, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31567726

RESUMO

BACKGROUND: Mannitol and hypertonic saline are widely used to treat raised intracranial pressure (ICP) after traumatic brain injury (TBI), but the clinical superiority of one over the other has not been demonstrated. METHODS: According to the PRISMA statement, this meta-analysis reports on randomized controlled trials investigating hypertonic saline compared with mannitol in the treatment of elevated ICP following TBI. The protocol for the literature searches (Medline, Embase, Central databases), quality assessment, endpoints (mortality, favorable outcome, brain perfusion parameters), and statistical analysis plan (including a trial sequential analysis) were prospectively specified and registered on the PROSPERO database (CRD42017057112). RESULTS: A total of 12 randomized controlled trials with 464 patients were eligible for inclusion in this analysis. Although there was a nonsignificant trend in favor of hypertonic saline, there were no significant differences in mortality between the 2 treatments (relative risk [RR]: 0.69, 95% confidence interval [CI]: 0.45, 1.04; P=0.08). There were also no significant differences in favorable neurological outcome between hypertonic saline (HS) and mannitol (RR: 1.28, 95% CI: 0.86, 1.90; P=0.23). There was no difference in ICP at 30 to 60 minutes after treatment (mean difference [MD]: -0.19 mm Hg, 95% CI: -0.54, 0.17; P=0.30), whereas ICP was significantly lower after HS compared with mannitol at 90 to 120 minutes (MD: -2.33 mm Hg, 95% CI: -3.17, -1.50; P<0.00001). Cerebral perfusion pressure was higher between 30 to 60 and 90 to 120 minutes after treatment with HS compared with after treatment with mannitol (MD: 5.48 mm Hg, 95% CI: 4.84, 6.12; P<0.00001 and 9.08 mm Hg, 95% CI: 7.54, 10.62; P<0.00001, respectively). Trial sequential analysis showed that the number of cases was insufficient to produce reliable statements on long-term outcomes. CONCLUSION: There are indications that HS might be superior to mannitol in the treatment of TBI-related raised ICP. However, there are insufficient data to reach a definitive conclusion, and further studies are warranted.


Assuntos
Lesões Encefálicas Traumáticas/complicações , Diuréticos Osmóticos/uso terapêutico , Hipertensão Intracraniana/etiologia , Hipertensão Intracraniana/terapia , Manitol/uso terapêutico , Solução Salina Hipertônica/uso terapêutico , Humanos
5.
J Clin Med ; 11(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35011868

RESUMO

Pituitary adenomas (PAs) are mostly benign endocrine tumors that can be treated by resection or medication. However, up to 10% of PAs show an aggressive behavior with invasion of adjacent tissue, rapid proliferation, or recurrence. Here, we provide an overview of target structures in aggressive PAs and summarize current clinical trials including, but not limited to, PAs. Mainly, drug targets in PAs are based on general features of tumor cells such as immune checkpoints, so that programmed cell death 1 (ligand 1) (PD-1/PD-L1) targeting may bear potential to cure aggressive PAs. In addition, epidermal growth factor receptor (EGFR), mammalian target of rapamycin (mTOR), vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF) and their downstream pathways are triggered in PAs, thereby modulating tumor cell proliferation, migration and/or tumor angiogenesis. Temozolomide (TMZ) can be an effective treatment of aggressive PAs. Combination of TMZ with 5-Fluorouracil (5-FU) or with radiotherapy could strengthen the therapeutic effects as compared to TMZ alone. Dopamine agonists (DAs) are the first line treatment for prolactinomas. Dopamine receptors are also expressed in other subtypes of PAs which renders Das potentially suitable to treat other subtypes of PAs. Furthermore, targeting the invasive behavior of PAs could improve therapy. In this regard, human matrix metalloproteinase (MMP) family members and estrogens receptors (ERs) are highly expressed in aggressive PAs, and numerous studies demonstrated the role of these proteins to modulate invasiveness of PAs. This leaves a number of treatment options for aggressive PAs as reviewed here.

6.
Healthcare (Basel) ; 8(4)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202727

RESUMO

BACKGROUND: Patients' fear of the coronavirus disease 2019 (COVID-19) may delay inevitable treatment, putting potential benefits at risk. This single-center retrospective study aims to analyze temporal relationships of the first wave of the COVID-19 pandemic in Germany with the number of patients who sought and received elective neurosurgical treatment at a German university hospital. METHODS: Daily outpatient numbers (ON) and elective procedures (EP) were recorded at our department between 1 January 2020 and 30 June 2020 (baseline: between 1 January 2019 and 30 June 2019). In patients who received EP, we recorded indication, outcome, and length of stay (LOS). Moving averages of ON (MAON) and of EP were calculated. Data on governmental action taken in response to the pandemic and on coronavirus-positive cases in Germany (CPCG) were superimposed. Exponential and arc tangent curves (ATC) were fitted to the absolute numbers of CPCG. Phase shifts were estimated, and Spearman's rank correlation coefficient, rho, was calculated between the 2020 MAON and the derivative function of the fitted ATC (DFATC). Wilcoxon rank sum served as statistical test. Significance was assumed with p values of less than 0.05. RESULTS: ON were significantly decreased in April 2020 as compared to April 2019 (p = 0.010). A phase shift between the German lockdown, the DFATC, and the decrease in MAON was not detected, while a phase shift of 10 days between the DFATC and the subsequent increase in MAON was detected. The DFATC was significantly negatively correlated (rho = -0.92, p < 0.0001) to the MAON until 31 March 2020, and, when shifted by 10 days, the DFATC was significantly negatively correlated (rho = -0.87, p < 0.0001) to the MAON from 01 April 2020. EP (p = 0.023), including the subset of non-oncological EP (p = 0.032), were significantly less performed in the first half of 2020 as compared to the first half of 2019. In March and April 2020, we conducted significantly more EP due to motor deficits (p = 0.0267, and less), visual disturbances (p = 0.0488), and spinal instability (p = 0.0012), and significantly less EP due to radicular pain (p = 0.0489), as compared to March and April 2019. LOS ranked significantly higher in patients who received cranial or spinal EP in March and April 2020 as compared to March and April 2019 (p = 0.0497). Significant differences in outcome were not observed. CONCLUSION: The beginning of the COVID-19 pandemic was correlated to an immediate and significant decrease in ON, and to a significant decrease in the number of EP performed. The subsequent increase in ON was delayed. Adequate measures to promote timely discharge of patients may become increasingly relevant as the pandemic proceeds. Although we observed a shift in the range of indications towards significantly more EP in patients with neurological deficiencies, care should be taken to avoid potentially deleterious delays of necessary elective treatment in future pandemic situations.

7.
FEBS Open Bio ; 10(11): 2489-2498, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33030286

RESUMO

Selective estrogen receptor modulators (SERMs) significantly affect survival and invasiveness of rodent pituitary adenoma (PA) cells. The impact of three clinically relevant SERMs (bazedoxifene, clomiphene, raloxifene) on invasiveness and on gene and protein expression of invasion-related proteases [matrix metalloproteinase-14 (MMP-14) and A disintegrin and metalloproteinase-12 (ADAM12)] was analyzed in murine PA cells (AtT-20 and TtT/GF). All SERMs significantly decreased cell invasiveness. Moreover, SERMs significantly decreased expression of ADAM12 mRNA in both cell lines and of MMP-14 mRNA in TtT/GF cells. Invasion rates of AtT-20 and TtT/GF significantly decreased after ADAM12 gene silencing, and the invasion rate of TtT/GF cells significantly decreased after MMP-14 gene silencing. All SERMs affected ADAM12 protein expression in AtT-20 cells whereas bazedoxifene and raloxifene decreased MMP-14 protein expression in TtT/GF cells. We conclude that SERMs attenuate invasiveness of murine PA cells by downregulating expression levels of invasion-related proteases MMP-14 and ADAM12.


Assuntos
Proteína ADAM12/genética , Adenoma/patologia , Metaloproteinase 14 da Matriz/genética , Neoplasias Hipofisárias/patologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Proteína ADAM12/metabolismo , Adenoma/genética , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Concentração Inibidora 50 , Metaloproteinase 14 da Matriz/metabolismo , Camundongos , Invasividade Neoplásica , Neoplasias Hipofisárias/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Global Spine J ; 10(2 Suppl): 41S-55S, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32528805

RESUMO

STUDY DESIGN: A prospective, case-based, observational study. OBJECTIVES: To investigate how microscope-based augmented reality (AR) support can be utilized in various types of spine surgery. METHODS: In 42 spinal procedures (12 intra- and 8 extradural tumors, 7 other intradural lesions, 11 degenerative cases, 2 infections, and 2 deformities) AR was implemented using operating microscope head-up displays (HUDs). Intraoperative low-dose computed tomography was used for automatic registration. Nonlinear image registration was applied to integrate multimodality preoperative images. Target and risk structures displayed by AR were defined in preoperative images by automatic anatomical mapping and additional manual segmentation. RESULTS: AR could be successfully applied in all 42 cases. Low-dose protocols ensured a low radiation exposure for registration scanning (effective dose cervical 0.29 ± 0.17 mSv, thoracic 3.40 ± 2.38 mSv, lumbar 3.05 ± 0.89 mSv). A low registration error (0.87 ± 0.28 mm) resulted in a reliable AR representation with a close matching of visualized objects and reality, distinctly supporting anatomical orientation in the surgical field. Flexible AR visualization applying either the microscope HUD or video superimposition, including the ability to selectively activate objects of interest, as well as different display modes allowed a smooth integration in the surgical workflow, without disturbing the actual procedure. On average, 7.1 ± 4.6 objects were displayed visualizing target and risk structures reliably. CONCLUSIONS: Microscope-based AR can be applied successfully to various kinds of spinal procedures. AR improves anatomical orientation in the surgical field supporting the surgeon, as well as it offers a potential tool for education.

9.
J Neurol Surg A Cent Eur Neurosurg ; 81(5): 430-441, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32438418

RESUMO

OBJECTIVE: The presence of multiple injuries in addition to a traumatic brain injury (TBI) is initially uncertain in most patients with posttraumatic coma. The interdisciplinary team of physicians in charge of initial treatment after hospital admission may face a collision of vital priorities. The purpose of this study was to analyze which diagnostic and surgical measures were given priority over others in comatose patients after injury and to draw conclusions from these data. METHODS: In this prospective multicenter cohort study, the outcomes of 1,003 comatose patients with suspected multiple injuries were studied. The analysis was divided into an early and a late stage. Diagnostic and surgical measures were analyzed for a 6-month period. The prognostic value of the Glasgow Coma Scale (GCS) and the World Federation of Neurosurgical Societies grading scale were investigated. RESULTS: Removal of intracranial hematomas and decompressive craniotomies were the most frequent procedures within the first 48 hours after admission to the hospital. Prognosis depends on the location and the combination of injuries. Outcome is significantly correlated to initial signs of brainstem dysfunction. The GCS did not adequately predict clinical outcome. CONCLUSION: Comatose patients with suspected multiple injuries should only be admitted to hospitals with a continuous neurosurgical service because intracranial operations are more frequent in the first 48 hours than extracranial operations. Depending on the neurologic status of the patient, an urgent surgical decompression may be essential for a good outcome. The GCS alone is not a sufficient tool for the neurologic assessment and the prognosis of patients with multiple injuries. The onset of clinical signs of brainstem dysfunction indicates a critical deterioration of the functioning of the central nervous system. The priority of surgical measures should be tailored accordingly.


Assuntos
Lesões Encefálicas Traumáticas/complicações , Coma/complicações , Traumatismo Múltiplo/complicações , Procedimentos Neurocirúrgicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas Traumáticas/cirurgia , Criança , Pré-Escolar , Estudos de Coortes , Descompressão Cirúrgica , Feminino , Escala de Coma de Glasgow , Hospitalização , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/cirurgia , Exame Neurológico , Prognóstico , Estudos Prospectivos , Adulto Jovem
10.
Neurosurg Focus ; 47(6): E11, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31786552

RESUMO

OBJECTIVE: Low registration errors are an important prerequisite for reliable navigation, independent of its use in cranial or spinal surgery. Regardless of whether navigation is used for trajectory alignment in biopsy or implant procedures, or for sophisticated augmented reality applications, all depend on a correct registration of patient space and image space. In contrast to fiducial, landmark, or surface matching-based registration, the application of intraoperative imaging allows user-independent automatic patient registration, which is less error prone. The authors' aim in this paper was to give an overview of their experience using intraoperative CT (iCT) scanning for automatic registration with a focus on registration accuracy and radiation exposure. METHODS: A total of 645 patients underwent iCT scanning with a 32-slice movable CT scanner in combination with navigation for trajectory alignment in biopsy and implantation procedures (n = 222) and for augmented reality (n = 437) in cranial and spine procedures (347 craniotomies and 42 transsphenoidal, 56 frameless stereotactic, 59 frame-based stereotactic, and 141 spinal procedures). The target registration error was measured using skin fiducials that were not part of the registration procedure. The effective dose was calculated by multiplying the dose length product with conversion factors. RESULTS: Among all 1281 iCT scans obtained, 1172 were used for automatic patient registration (645 initial registration scans and 527 repeat iCT scans). The overall mean target registration error was 0.86 ± 0.38 mm (± SD) (craniotomy, 0.88 ± 0.39 mm; transsphenoidal, 0.92 ± 0.39 mm; frameless, 0.74 ± 0.39 mm; frame-based, 0.84 ± 0.34 mm; and spinal, 0.80 ± 0.28 mm). Compared with standard diagnostic scans, a distinct reduction of the effective dose could be achieved using low-dose protocols for the initial registration scan with mean effective doses of 0.06 ± 0.04 mSv for cranial, 0.50 ± 0.09 mSv for cervical, 4.12 ± 2.13 mSv for thoracic, and 3.37 ± 0.93 mSv for lumbar scans without impeding registration accuracy. CONCLUSIONS: Reliable automatic patient registration can be achieved using iCT scanning. Low-dose protocols ensured a low radiation exposure for the patient. Low-dose scanning had no negative effect on navigation accuracy.


Assuntos
Encefalopatias/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Neuronavegação/métodos , Doenças da Coluna Vertebral/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encefalopatias/cirurgia , Criança , Pré-Escolar , Craniotomia , Feminino , Marcadores Fiduciais , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Doenças da Coluna Vertebral/cirurgia , Técnicas Estereotáxicas , Adulto Jovem
11.
Medicina (Kaunas) ; 55(11)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683909

RESUMO

Background and Objectives: To identify predictors of outcome after aneurysmal subarachnoid hemorrhage (aSAH) in our interdisciplinary setting. Materials and Methods: 176 patients who had been treated for aSAH by a team of neurosurgeons and neuroradiologists between 2009 and 2017 were analyzed retrospectively. Age, gender, clinical presentation according to the Hunt and Hess (H&H) grading on admission, overall clot burden, aneurysm localization, modality of aneurysm obliteration, early deterioration (ED), occurrence of vasospasm in transcranial Doppler ultrasonography, delayed cerebral ischemia (DCI), spasmolysis, decompressive craniectomy (DC), cerebrospinal fluid (CSF) shunt placement, deep vein thrombosis (DVT), pulmonary embolism (PE), severe cardiac events (SCE), mortality on Days 14, and 30 after admission, and outcome at one year after the hemorrhage according to the Glasgow Outcome Scale (GOS) were recorded. Chi square, Fisher's exact, Welch's t, and Wilcoxon rank sum served as statistical tests. Generalized linear models were fitted, and ordered logistic regression was performed. Results: SCE (p = 0.049) were a significant predictor of mortality at 14 days after aSAH, but not later during the first year after the hemorrhage. Clipping as opposed to coiling (p = 0.049) of ruptured aneurysms was a significant predictor of survival on Day 30 after aSAH, but not later during the first year after the hemorrhage, while coiling as opposed to clipping of ruptured aneurysms was significantly related to a lower frequency of DVT during hospitalization (p = 0.024). Aneurysms of the anterior circulation were significantly more often clipped, while aneurysms of the posterior circulation were significantly more often coiled (p < 0.001). Age over 70 years (p = 0.049), H&H grade on admission (p = 0.022), overall clot burden (p = 0.035), ED (p = 0.009), DCI (p = 0.013), DC (p = 0.0005), and CSF shunt placement (p = 0.038) proved to be predictive of long-term outcome after aSAH. Conclusion: Long-term results after clipping and coiling of ruptured aneurysms appear equal in an interdisciplinary setting that takes aneurysm localization, available staff, and equipment into account.


Assuntos
Equipe de Assistência ao Paciente/normas , Hemorragia Subaracnóidea/terapia , Resultado do Tratamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente/tendências , Estudos Retrospectivos , Hemorragia Subaracnóidea/epidemiologia , Tomografia Computadorizada por Raios X/métodos
12.
Eur Spine J ; 28(7): 1697-1711, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30953169

RESUMO

PURPOSE: To implement a straightforward workflow that allows to establish augmented reality (AR) support in spine surgery. METHODS: Intraoperative computed tomography (iCT) applying a 32-slice movable scanner was used for navigation registration in a series of 10 patients who underwent surgery for extra- or intradural spinal lesions. Preoperative multimodal image data were integrated by nonlinear registration with the iCT images. Automatic segmentation was used to delineate the 3-dimensional (3-D) outline of the vertebra, and in addition, the tumor extent, as well as implants, was segmented and visualized. RESULTS: Automatic patient registration without user interaction resulted in high navigation accuracy with a mean registration error of only about 1 mm. Moreover, the workflow for establishing AR was straightforward and could be easily integrated in the normal surgical procedure. Low-dose iCT protocols resulted in a radiation exposure of 0.35-0.98 mSv for cervical, 2.16-6.92 mSv for thoracic, and 3.55-4.20 mSv for lumbar surgeries, which is a reduction in the effective radiation dose by 70%. The segmented structures were intuitively visualized in the surgical field using the heads-up display of the operating microscope. In parallel, the microscope video was superimposed with the segmented 3-D structures, which were visualized in a semitransparent manner along with various display modes of the image data. CONCLUSIONS: A microscope-based AR environment was successfully implemented for spinal surgery. The application of iCT for registration imaging ensures high navigational accuracy. AR greatly supports the surgeon in understanding the 3-D anatomy thereby facilitating surgery. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Realidade Aumentada , Imageamento Tridimensional , Tomografia Computadorizada Multidetectores , Procedimentos Ortopédicos/métodos , Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos
13.
World Neurosurg ; 125: e873-e883, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30763743

RESUMO

OBJECTIVE: We investigated how augmented reality (AR) can be applied to support transsphenoidal surgery. METHODS: AR was established using the head-up displays integrated into operating microscopes. Navigation registration was performed with either fiducial-based or automatic registration using intraoperative computed tomography (iCT). Correct microscope calibration was ensured by checking the geometric overlap between the AR representation of the reference array and the 3-dimensional reality while focusing on the reference array. RESULTS: From a consecutive single-surgeon series of 288 transsphenoidal procedures, 47 patients (16.3%) had undergone microscope-based AR to visualize the target and risk structures. AR was smoothly integrated into the surgical workflow. AR accuracy depended on navigation accuracy and microscope calibration. The target registration error in patients with fiducial-based registration was 2.33 ± 1.30 mm. Automatic, user-independent iCT-based registration significantly (P < 0.001) increased AR accuracy (target registration error, 0.83 ± 0.44 mm). Applying low-dose iCT protocols reduced the effective dose caused by iCT registration scanning to within the range of a single chest radiograph (0.041 mSv). No vascular injuries and no aggravation of neurological deficits occurred in the present series. AR greatly facilitated orientation in the reoperations and the patients with anatomical variants, thereby increasing surgeon comfort. Enhanced AR visualizations improved the 3-dimensional perception compared with the standard display of dashed lines by the head-up display of the operating microscope. CONCLUSIONS: Microscope-based AR is a reliable tool to increase patient safety in complicated transsphenoidal procedures. Intraoperative imaging-based automatic patient registration is recommended.


Assuntos
Realidade Aumentada , Imageamento Tridimensional/métodos , Neuronavegação/métodos , Cirurgia Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Int J Comput Assist Radiol Surg ; 14(1): 169-182, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30171444

RESUMO

PURPOSE: In surgery of C1-C2 fractures, standard navigation for screw placement based on preoperative image data was compared with intraoperative imaging guidance applying intraoperative computed tomography (iCT) with a special focus on accuracy of screw placement, workflow, and radiation exposure. METHODS: A single surgeon series of 16 consecutive patients with C1-C2 trauma was retrospectively analyzed. Seven patients were operated with standard navigation; preoperative image data were registered by a 20-point surface-matching process for each vertebra. Nine patients were operated with iCT guidance, allowing automatic navigation registration. Screw placement was examined and graded with either iCT or postoperative CT. Dose length product of CT and dose area products of fluoroscopy scans were assessed; effective radiation doses were estimated based on conversion factors. Radiation doses of intraoperative and postoperative X-ray and/or CT diagnostics for each group were summarized to compare the total effective doses. RESULTS: A total number of 72 screws were placed, 26 in the standard navigation group including 24 screws in C1 and C2, and 46 screws in the iCT group including 34 screws in C1 and C2. 15.38% (n = 4) of the C2 screws showed a grade 1 deviation and 3.8% (n = 1) a grade 2 deviation applying standard navigation. There was no misplacement of screws in the iCT group. Mean operating time in the standard navigation group was 186.57 min versus 157.11 min in the iCT group, while the mean summarized effective dose was 1.129 mSv in the standard navigation and 2.129 mSv in the iCT group. CONCLUSION: iCT navigated surgery can lead to higher accuracy and shorter operating time compared to standard navigated operations. iCT is a safe and straightforward procedure allowing reduction in radiation exposure of the medical staff, while modified scan protocols resulted in a radiation exposure that is lower than in standard diagnostic neck CT.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Parafusos Ósseos , Vértebras Cervicais/cirurgia , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Exposição à Radiação , Estudos Retrospectivos , Fraturas da Coluna Vertebral/cirurgia , Adulto Jovem
15.
J Steroid Biochem Mol Biol ; 187: 88-96, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30439415

RESUMO

Although the molecular mechanisms underlying the formation of pituitary adenomas are largely unknown, it is clear that estrogen plays a key role in the pathogenesis of pituitary adenomas. Though this is exemplified by an investigation of fulvestrant in the pituitary adenoma cell line GH3, no systematic studies on the effects of selective estrogen receptor modulators (SERMs) on functional properties of pituitary adenoma cell lines to modulate cell migration, cell invasion, and cell survival are available. Here we analyzed the effects of fulvestrant and three SERMs, bazedoxifene, clomifene, and raloxifene, on pituitary adenomas cell lines AtT20, TtT/GF, and GH3. In cell survival assays, clomifene was shown to be the most potent compound in all three cell lines with IC50 values ranging between 2, 6, and 10 µM, respectively, depending on the cell type. Raloxifene and bazedoxifene were also effective but to a lower extent. Also, all SERMs affected migratory and invasive behavior of pituitary adenoma cells. Mechanistically, treatment of cells with SERMs caused cell apoptosis, as demonstrated by Caspase 3/7 activity and western blot assays. In addition, western blots demonstrate activation of p53 in TtT/GF cells and loss of ERK1/2 activation in AtT20 cells. In contrast, fulvestrant was only effective in GH3 cells. Thus, the general applicability of SERMs for pituitary adenoma cells might be promising in clinical applications for the treatment of pituitary adenomas.


Assuntos
Adenoma/tratamento farmacológico , Antagonistas do Receptor de Estrogênio/farmacologia , Fulvestranto/farmacologia , Invasividade Neoplásica/prevenção & controle , Neoplasias Hipofisárias/tratamento farmacológico , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Adenoma/metabolismo , Adenoma/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Invasividade Neoplásica/patologia , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia
16.
Int J Cancer ; 139(6): 1327-39, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27144841

RESUMO

Invasion of tumor cells critically depends on cell-cell or cell-extracellular matrix interactions. Enzymes capable of modulating these interactions belong to the proteinase families of ADAM (a disintegrin and metalloprotease) and MMP (matrix metalloprotease) proteins. Our objective is to examine their expression levels and evaluate the relationship between expression levels and cavernous sinus invasion in pituitary adenomas. Tissue samples from 35 patients with pituitary adenomas were analyzed. Quantitative real-time polymerase chain reaction (qPCR) was employed to assess mRNA expression levels for ADAM and MMP genes. Protein levels were examined using immunohistochemistry and Western Blot. Correlation analyses between expression levels and clinical parameters were performed. By silencing ADAM12 and MMP-14 with siRNA in a mouse pituitary adenoma cell line (TtT/GF), their cellular effects were investigated. In our study, nine women and 26 men were included, with a mean age of 53.1 years (range 15-84 years) at the time of surgery. There were 19 cases with cavernous sinus invasion. The proteins ADAM12 and MMP-14 were significantly up-regulated in invasive adenomas compared to noninvasive adenomas. Both human isoforms of ADAM12 (ADAM12L and ADAM12s) were involved in tumor invasion; moreover, ADAM12L was found to correlate positively with Ki-67 proliferation index in pituitary adenomas. In TtT/GF pituitary adenoma cells, silencing of ADAM12 and MMP-14 significantly inhibited cell invasion and migration, respectively, whereas only silencing of ADAM12 suppressed cell proliferation. We conclude that ADAM12 and MMP-14 are associated with cavernous sinus invasion in pituitary adenomas, which qualifies these proteins in diagnosis and therapy.


Assuntos
Proteína ADAM12/metabolismo , Seio Cavernoso/patologia , Metaloproteinase 14 da Matriz/metabolismo , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Proteína ADAM12/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Expressão Gênica , Inativação Gênica , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Masculino , Metaloproteinase 14 da Matriz/genética , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/cirurgia , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adulto Jovem
17.
J Neurol Surg A Cent Eur Neurosurg ; 76(6): 456-65, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26216734

RESUMO

OBJECTIVE: The timely detection of neurologic deterioration can be critical for the survival of a neurosurgical patient following head injury. Because little reliable evidence is available on the prognostic value of the clinical sign "extensor response" in comatose posttraumatic patients, we investigated the correlation of this clinical sign with outcome and with early radiologic findings from magnetic resonance imaging (MRI). METHODS: This retrospective analysis of prospectively obtained data included 157 patients who had remained in a coma for a minimum of 24 hours after traumatic brain injury. All patients received a 1.5-T MRI within 10 days (median: 2 days) of the injury. The correlations between clinical findings 12 and 24 hours after the injury-in particular, extensor response and pupillary function, MRI findings, and outcome after 1 year-were investigated. Statistical analysis included contingency tables, Fisher exact test, odds ratios (ORs) with confidence intervals (CIs), and weighted κ values. RESULTS: There were 48 patients with extensor response within the first 24 hours after the injury. Patients with extensor response (World Federation of Neurosurgical Societies coma grade III) statistically were significantly more likely to harbor MRI lesions in the brainstem when compared with patients in a coma who had no further deficiencies (coma grade I; p = 0.0004 by Fisher exact test, OR 10.8 with 95% CI, 2.7-42.5) and patients with unilateral loss of pupil function (coma grade II; p = 0.0187, OR 2.8 with 95% CI, 1.2-6.5). The correlation of brainstem lesions as found by MRI and outcome according to the Glasgow Outcome Scale after 1 year was also highly significant (p ≤ 0.016). CONCLUSION: The correlation of extensor response and loss of pupil function with an unfavorable outcome and with brainstem lesions revealed by MRI is highly significant. Their sudden onset may be associated with the sudden onset of brainstem dysfunction and should therefore be regarded as one of the most fundamental warning signs in the clinical monitoring of comatose patients.


Assuntos
Lesões Encefálicas/complicações , Tronco Encefálico/patologia , Coma/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde , Distúrbios Pupilares/fisiopatologia , Reflexo de Babinski/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Coma/etiologia , Coma/patologia , Feminino , Seguimentos , Escala de Coma de Glasgow , Escala de Resultado de Glasgow , Humanos , Lactente , Legislação Médica , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
J Neurol Surg A Cent Eur Neurosurg ; 76(1): 30-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25072317

RESUMO

BACKGROUND: Granular cell astrocytomas (GCAs) are rarely encountered aggressive glial neoplasms. Treatment options comprise surgery, radiotherapy, and chemotherapy. Due to the small number of cases, a standard therapeutic regimen for GCA does not exist. MATERIAL AND METHODS: We report on the case of a 64-year-old woman with GCA subjected to tumor biopsy followed by radiochemotherapy with temozolomide. We provide clinical, histopathologic, and magnetic resonance imaging findings as well as a complete follow-up. To assess the relation of age, gender, time of publication, and different treatment options with survival we performed log-rank tests and calculated Cox regression models and hazard ratios in data from all available reports on GCA. RESULTS: A significant difference in survival rates in favor of adjuvant therapy (radiotherapy or radiochemotherapy) at 12 months was found. Age > 70 years at the time of diagnosis had a significantly unfavorable impact on survival at 12 months. Although not statistically significant, a tendency toward higher probability of survival at 12 months was found in cases reported after 2002. In surgically treated patients, we could not find a significant impact of extent of resection on survival. A significant impact of gender on survival was not found. CONCLUSION: Adjuvant therapy is significantly related to a higher probability of survival at 12 months and may therefore be recommended for patients with a GCA. Further analysis of these rare neoplasms is warranted.


Assuntos
Astrocitoma/mortalidade , Astrocitoma/terapia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/farmacologia , Criança , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Evolução Fatal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Lobo Occipital/patologia , Radioterapia Adjuvante , Temozolomida
20.
Onco Targets Ther ; 9: 1269-76, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24092990

RESUMO

OBJECTIVE: Resveratrol is a phytoestrogen with various antiproliferative and proapoptotic effects. This in vitro study aimed to analyze the effect of resveratrol on the viability and expression of modulators of apoptosis in GH3 pituitary adenoma cells of the rat. METHODS: GH3 cells were incubated with resveratrol concentrations from 20 to 100 µM for 48-72 hours. Cell viability was quantified using a hemocytometer. We assessed the ability of resveratrol to kill GH3 cells by an enzyme-linked immunosorbent assay (ELISA) of nucleosome liberation and by DNA degradation (unidimensional gel electrophoresis). Relative messenger RNA (mRNA) expression of survivin, B-cell lymphoma-2 protein (BCL-2) and BCL-2-associated X protein (BAX) normalized to ß2 microglobulin was measured using quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: GH3 cell survival significantly decreased with increasing concentrations of resveratrol. In GH3 cells treated with 100 µM resveratrol, ELISA demonstrated a significant rise of nucleosome liberation, which typically occurs during apoptosis. In parallel, gel electrophoresis showed degradation of DNA into random fragments, pointing to a necrotic mode of cell death in most GH3 cells. In GH3 cells treated with 100 µM resveratrol, qRT-PCR detected a significant decrease of BCL-2 mRNA expression and a decrease of survivin mRNA expression, whereas a change of BAX mRNA expression could not be found. The BAX/BCL-2 ratio was significantly increased in GH3 cells after resveratrol treatment. CONCLUSIONS: Resveratrol reduces GH3 cell viability in a dose-dependent manner by inducing nonapoptotic cell death and apoptosis. Apoptosis in GH3 cells is probably mediated by resveratrol-dependent downregulation of apoptosis inhibitors, namely BCL-2 and possibly survivin. Further investigation of the potential effects of resveratrol on pituitary adenoma cells is warranted.

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