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1.
Acta Radiol ; 64(2): 769-775, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35466686

RESUMO

BACKGROUND: Moyamoya disease (MMD) and non-MMD have different pathogenesis, clinical presentation, and treatment policy. PURPOSE: To identify differences in hemodynamics between MMD and non-MMD using intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT). MATERIAL AND METHODS: Patients who had undergone 99mTc-ECD or 123I-IMP SPECT, and IVIM imaging were retrospectively studied. IVIM imaging was acquired using six different b-values. Cerebral blood flow ratio (CBFR) in the basal ganglia was calculated using a standardized volume-of-interest template. The cerebellum was used as a reference region. IVIM perfusion fraction (f) was obtained using a two-step fitting algorithm. Elliptical regions of interest were placed in bilateral basal ganglia on the IVIM f map. Patients were classified into MMD and non-MMD groups. The correlation between CBFR and mean IVIM f (fmean) in the basal ganglia was evaluated using Spearman's rank correlation coefficient. RESULTS: In total, 20 patients with MMD and 28 non-MMD patients were analyzed. No significant differences in fmean were observed among MMD, affected hemisphere with non-MMD (non-MMDaff), and unaffected hemispheres with non-MMD (non-MMDunaff). A negative correlation was seen between fmean and CBFR in the MMD group (r = -0.40, P = 0.0108), but not in the non-MMD group (non-MMDaff, r = 0.07, P = 0.69; non-MMDunaff, r = -0.22, P = 0.29). No significant differences were found among MMD and non-MMD patients, irrespective of SPECT tracers. CONCLUSION: The combination of IVIM MRI and SPECT appears to allow non-invasive identification of differences in hemodynamics between MMD and non-MMD.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , Tomografia Computadorizada de Emissão de Fóton Único , Gânglios da Base/diagnóstico por imagem
2.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 33(6): 345-349, nov.-dic. 2022. ilus
Artigo em Inglês | IBECS | ID: ibc-212993

RESUMO

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity (AU)


La actividad proliferativa examinada por el índice de etiquetado Ki67 (LI) desempeña un papel fundamental en el tratamiento del tumor neuroendocrino gastrointestinal (GI-NET). Pocos informes indican la heterogeneidad intrapaciente del Ki67-LI entre las localizaciones de los tumores metastásicos. Presentamos un caso de metástasis cerebrales y orbitales de GI-NET que mostró discrepancia del Ki67-LI. Una mujer de 71 años a la que se le diagnosticó un GI-NET con metástasis hepáticas y óseas y que realizó tratamiento médico, presentó cefalea, exoftalmos derecho y dolor de ojo derecho, y fue remitida a nuestro departamento. La imagen de resonancia magnética reveló que los tumores en la región occipital izquierda y la órbita derecha. Diagnosticamos como metástasis tumores cerebrales y orbitales de GI-NET. Se realizó la extirpación quirúrgica de ambas lesiones sintomáticas y se confirmó patológicamente el diagnóstico. Los estudios inmunohistoquímicos revelaron la discrepancia del Ki67-LI de las lesiones (tumor cerebral: 8% frente a tumor orbitario: 22%). El muestreo de múltiples focos metastásicos puede evitar que se subestime la actividad proliferativa del tumor (AU)


Assuntos
Humanos , Feminino , Idoso , Tumores Neuroendócrinos/patologia , Neoplasias Encefálicas/secundário , Neoplasias Orbitárias/secundário , Antígeno Ki-67/sangue , Imageamento por Ressonância Magnética , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Orbitárias/diagnóstico por imagem , Imuno-Histoquímica
3.
Neurocirugia (Astur : Engl Ed) ; 33(6): 345-349, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36333091

RESUMO

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity.


Assuntos
Tumores Neuroendócrinos , Neoplasias Orbitárias , Feminino , Humanos , Idoso , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Antígeno Ki-67/metabolismo , Neoplasias Orbitárias/diagnóstico por imagem , Encéfalo
4.
J Neurol Surg B Skull Base ; 83(Suppl 3): e635-e636, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36068909

RESUMO

Tuberculum sellae meningiomas pose significant challenges because they are surrounded by crucial neurovascular structures, such as the optic and oculomotor nerves, pituitary stalk, internal carotid artery and its branches, and the anterior cerebral arteries. Even if small, such meningiomas frequently extend to the optic canal that is considered a poor prognostic factor for vision. In this video clip, we illustrate the case of a 60-year-old female who had an approximately 3-cm tuberculum sellae meningioma with optic canal involvement. She underwent surgical resection of the tumor through a pterional approach. After extradural optic canal unroofing, detaching, devascularizing, and debulking the tumor, careful dissection of the meningioma from the surrounding tissues was performed. Next, the tumor extensions into both of the optic canals were removed. Finally, coagulation and resection of the tumor origin on the dura of the tuberculum sellae following Simpson's grade-I resection were performed. Histopathology revealed that the tumor was a World Health Organization (WHO) grade-I meningioma. The patient had an uneventful postoperative course and her visual acuity was preserved, with no visual field defect on postoperative visual examination. In this video, the basic surgical techniques in performing extradural optic canal unroofing, preserving the arachnoid plane, and stay in collect layer, which is the essential technique for dissecting meningiomas and for preserving neurovascular structures, are demonstrated. The link to the video can be found at: https://youtu.be/vD54Iji0C4Q .

5.
Sci Rep ; 12(1): 16277, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175487

RESUMO

Glioblastoma is the most common brain tumor with dismal outcomes in adults. Metabolic remodeling is now widely acknowledged as a hallmark of cancer cells, but glioblastoma-specific metabolic pathways remain unclear. Here we show, using a large-scale targeted proteomics platform and integrated molecular pathway-level analysis tool, that the de novo pyrimidine synthesis pathway and serine synthesis pathway (SSP) are the major enriched pathways in vivo for patients with glioblastoma. Among the enzymes associated with nucleotide synthesis, RRM1 and NME1 are significantly upregulated in glioblastoma. In the SSP, SHMT2 and PSPH are upregulated but the upstream enzyme PSAT1 is downregulated in glioblastoma. Kaplan-Meier curves of overall survival for the GSE16011 and The Cancer Genome Atlas datasets revealed that high SSP activity correlated with poor outcome. Enzymes relating to the pyrimidine synthesis pathway and SSP might offer therapeutic targets for new glioblastoma treatments.


Assuntos
Glioblastoma , Adulto , Vias Biossintéticas , Glioblastoma/genética , Humanos , Nucleotídeos , Pirimidinas , Serina
6.
Cureus ; 14(7): e26534, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35936185

RESUMO

OBJECTIVE: Patients with carotid stenosis risk cognitive impairment even after carotid endarterectomy (CEA) because of the long-term presence of vascular risk factors. Early prediction of cognitive decline is useful because early appropriate training for impaired cognitive domains can improve their functions. Ankle-brachial index (ABI) and cardio-ankle vascular index (CAVI) are frequently used as general indicators of systemic atherosclerosis and are associated with cognitive function in the general population. This study aimed to evaluate the utility of those vascular biomarkers for predicting cognitive decline in patients after CEA. METHODS: Patients who had undergone both CEA at our institute and cognitive evaluations between March 2016 and January 2022 were invited to participate in this study. Associations between ABI or CAVI three years before baseline and cognitive function at baseline were assessed retrospectively in 94 patients, and associations between ABI or CAVI at baseline and three-year changes in cognitive functions were assessed prospectively in 24 patients. Cognitive functions were assessed using the Frontal Assessment Battery (FAB) and Neurobehavioral Cognitive Status Examination (Cognistat). RESULTS: Low ABI three years before baseline was associated with poor performances on Cognistat and FAB at baseline. ABI, as a continuous measure, three years before baseline, showed positive linear associations with total Cognistat score and subscores for naming, construction, and judgment at baseline. The Wilcoxon signed-rank test showed that the total Cognistat score, total FAB score, and subscores for attention and inhibitory control declined after three years. CAVI at baseline was negatively associated with three-year changes in total Cognistat score and subscores for naming, construction, and memory. CONCLUSION: Cognitive function can decline over time in patients with carotid stenosis even after CEA. ABI and CAVI might be useful to predict cognitive function and its decline among patients who have undergone CEA.

7.
NMC Case Rep J ; 9: 151-155, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35836492

RESUMO

Endovascular embolization of the middle meningeal artery (MMA) has been reported as an effective method for treating chronic subdural hematoma (CSDH); however, its preventive effect on CSDH following craniotomy is unknown. We present a case in which MMA embolization was ineffective in preventing CSDH following craniotomy. A 56-year-old man who complained of diplopia was diagnosed with sphenoid ridge meningioma with a 3-cm diameter. MMA embolization prior to the operation and total surgical removal of the tumor were performed. Two months postoperatively, the patient complained of headache and hemiparesis of the left side. CSDH with a 15-mm thickness and a midline shift was observed. MMA embolization before inflammation may not play a role in preventing CSDH development because MMA embolization is considered effective in CSDH because it is associated with the blood supply of neovessels that are newly formed due to inflammation. Therefore, MMA embolization might not be effective in preventing the occurrence of CSDH following craniotomy.

8.
World Neurosurg ; 165: e346-e351, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35724887

RESUMO

OBJECTIVE: The long-term outcomes of cognitive function in moyamoya disease remain unknown. We aimed to assess 5-year changes in cognitive function in adult moyamoya disease patients and to evaluate the value of the magnetic resonance angiography (MRA) steno-occlusive score to predict cognitive changes. METHODS: Participants comprised 20 consecutive patients whose cognitive functions had been evaluated using the Frontal Assessment Battery (FAB) and Neurobehavioral Cognitive Status Examination (Cognistat) at baseline and reassessed 5 years later. RESULTS: The total FAB score and total Cognistat score were lower after 5 years in 9 patients each. The Wilcoxon signed-rank test showed that subscores for conceptualization and comprehension increased, while subscores for mental flexibility, programming, and inhibitory control significantly decreased after 5 years. The right MRA total score and right posterior cerebral artery score were negatively associated with 5-year changes in the total FAB score and total Cognistat score. The right posterior cerebral artery score was significantly associated with changes in subscores for mental flexibility, programming, sensitivity to interference, and construction. CONCLUSIONS: Specific cognitive domains can decline over time in patients with adult moyamoya disease. MRA findings might be useful for predicting future declines in cognitive function.


Assuntos
Doença de Moyamoya , Adulto , Cognição , Humanos , Angiografia por Ressonância Magnética , Artéria Cerebral Posterior
9.
Neuroradiol J ; 35(6): 777-779, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35503008

RESUMO

We report a case of cystic meningioma at the left cerebellopontine angle (CPA). Magnetic resonance imaging demonstrated both solid and cystic components in the tumor. The cystic component appeared slightly hyperintense compared to cerebrospinal fluid on fluid-attenuated inversion recovery (FLAIR) imaging. A hypointense tubular structure was identified in the cystic component on 3D driven equilibrium sequencing. These imaging findings are unusual for cystic meningioma. However, awareness of these unusual imaging features is important to determine appropriate treatment strategies although cystic meningioma at the CPA is extremely rare.


Assuntos
Neoplasias Cerebelares , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Meningioma/patologia , Ângulo Cerebelopontino/diagnóstico por imagem , Ângulo Cerebelopontino/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/cirurgia , Neoplasias Cerebelares/patologia
10.
Cureus ; 14(1): e21610, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35228967

RESUMO

Objective Preoperative diagnosis of tumor grade can assist in treatment-related decision-making for patients with intracranial meningioma. This study aimed to distinguish between high-grade and low-grade meningiomas using conventional CT and MRI. Methodology We retrospectively analyzed 173 consecutive patients with intracranial meningioma (149 low-grade and 24 high-grade tumors) who were treated surgically at the National Hospital Organization Kyushu Medical Center from 2008 to 2020. Clinical and radiological features, including tumor doubling time (Td) and relative growth rate (RGR), were compared between low-grade and high-grade meningiomas. Results Multivariate logistic regression analysis showed that symptomatic tumor (p=0.001), non-skull base location (p=0.006), irregular tumor shape (p=0.043), tumor heterogeneity (p=0.025), and peritumoral brain edema (p=0.003) were independent predictors of high-grade meningioma. In 53 patients who underwent surgery because of tumor progression, progression to symptoms (p=0.027), intratumoral heterogeneity (p<0.001), peritumoral brain edema (p=0.001), larger tumor volume (p=0.005), shorter Td (p<0.001), and higher RGR (P<0.001) were significantly associated with high-grade meningioma. Receiver operating characteristics (ROC) curve analysis showed that the optimal Td and annual RGR cut-off values to distinguish high-grade from low-grade meningioma were 460.5 days and 73.2%, respectively (100% sensitivity and 78.6% specificity). Conclusion Based on our findings, conventional CT and MRI are useful methods to predict meningioma grades before surgery. High-grade lesions are associated with non-skull base location, irregular tumor shape, intratumoral heterogeneity, and peritumoral brain edema. High-grade meningioma should be suspected in tumors that exhibit Td <460.5 days or annual RGR >73.2% or those that develop intratumoral heterogeneity or surrounding brain edema on surveillance imaging.

11.
J Clin Neurosci ; 92: 78-84, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34509267

RESUMO

Endoscopic treatment is a potential therapeutic addition to chronic subdural hematoma (CSDH) surgery. However, the effect of endoscopic treatment remains controversial. Herein, we examined the optimal indication for endoscopic treatment in CSDH surgery. We retrospectively analyzed 380 consecutive patients with CSDH who underwent single burr-hole craniostomy. We defined postoperative rebleeding as radiological re-accumulation or increased computed tomography value of the hematoma. Reoperation was performed following further hematoma accumulation and/or neurological deterioration. Complicated CSDH was radiologically defined as a hematoma with a clot and/or fibrous septum. There were no differences in baseline characteristics or postoperative mortality and morbidity between the endoscope (97 patients) and control (283 patients) groups. The incidence of postoperative rebleeding (9.3% vs 25.1%, respectively; P = 0.001) and reoperation (0% vs 9.2%, respectively; P = 0.004) were significantly lower in the endoscope group versus controls. Multivariate analysis showed that males (odds ratio 2.14, 95% confidence interval 1.19-3.81; P = 0.012) and endoscopy (odds ratio 0.29, 95% confidence interval 0.13-0.59; P = 0.001) were independently associated with postoperative rebleeding. When CSDHs were divided into two types based on hematoma component, 175 patients exhibited complicated CSDH. There was a significant reduction in postoperative rebleeding (6.5% vs 23.0%, respectively; P = 0.010) and reoperation (0% vs 9.7%, respectively; P = 0.027) in complicated CSDH patients. Endoscopic treatment in CSDH surgery does not increase the risk of surgical complications. Complicated CSDH with a clot and/or septum may be an optimal indication for endoscopic treatment in CSDH surgery to reduce postoperative recurrence.


Assuntos
Hematoma Subdural Crônico , Drenagem , Endoscopia , Hematoma Subdural Crônico/diagnóstico por imagem , Hematoma Subdural Crônico/cirurgia , Humanos , Masculino , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Trepanação
12.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34154907

RESUMO

Proliferative activity examined by Ki67 labeling index (LI) plays pivotal role for managing gastrointestinal neuroendocrine tumor (GI-NET). Few reports indicated the intra-patient heterogeneity of Ki67-LI among metastatic tumor sites. We report a case of brain and orbital metastases from GI-NET that showed discrepancy of the Ki67-LI. A 71 year-old woman who was diagnosed as GI-NET with liver and bone metastases and performed medical therapy, had headache, right exophthalmos, and pain of right eye and was referred to our department. Magnetic resonance image revealed that tumors in the left occipital region and right orbit. We diagnosed as metastatic brain and orbital tumors from GI-NET. Surgical removal of both symptomatic lesions was performed and the diagnosis was pathologically confirmed. Immunohistochemical studies revealed the discrepancy of the Ki67-LI of the lesions (brain tumor: 8% versus orbital tumor: 22%). Sampling of multiple metastatic sites may prevent underestimate tumor proliferative activity.

13.
Cureus ; 13(3): e14028, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33889466

RESUMO

Benign brain tumors largely affect the brain and can lead to reversible dementia, which can be resolved following the treatment of the primary etiology. Herein, we report three cases of relatively large frontal meningiomas in patients who presented with cognitive impairment as initial symptoms. The three participants demonstrated notable dementia alongside frontal meningioma. Following resection, all patients showed dramatic cognitive function improvement, and they successfully returned to society. Our cases illustrate the benefit of active surveillance with neuroimaging in selected patients, especially those who present with acute or subacute dementia.

14.
Oper Neurosurg (Hagerstown) ; 21(2): E83-E88, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33861318

RESUMO

BACKGROUND: The inferior petroclival vein (IPV) courses along the extracranial surface of the petroclival fissure. It is occasionally involved in vascular diseases and has recently been used for vascular access to the cavernous sinus. However, detailed descriptions of its anatomy are currently lacking. OBJECTIVE: To define the anatomic relationship between the IPV and its surrounding structures based on cadaveric dissection and radiological analysis. METHODS: A dry skull and an injected cadaver head were examined to reveal the relationships between the IPV and its surrounding structures. The existence of the IPV and its relationships with other venous structures were also examined by contrast-enhanced, fat-suppressed T1-weighted magnetic resonance imaging in 26 patients (51 sides). RESULTS: The entire course of the IPV was shown via stepwise cadaver dissection from below. Its relationships with surrounding structures, such as the jugular bulb, sigmoid sinus, inferior petrosal sinus, petrosal venous confluence, and the posterior, lateral, and anterior condylar veins, were also shown. In the radiological analysis, the IPV was identified on all sides. The rostral end of the vein was connected to the venous plexus around the carotid artery on all sides. The vein drained into the caudal end of the inferior petrosal sinus (49/51 sides, 96.1%) or into the anterior condylar vein (2/51 sides, 3.9%). CONCLUSION: A precise understanding of the anatomy of the IPV will enable endovascular and skull base surgeons to achieve diagnoses and gain safe access to lesions involving the IPV.


Assuntos
Seio Cavernoso , Veias Cerebrais , Cadáver , Veias Cerebrais/diagnóstico por imagem , Veias Cerebrais/cirurgia , Cavidades Cranianas/diagnóstico por imagem , Cavidades Cranianas/cirurgia , Humanos , Base do Crânio/diagnóstico por imagem , Base do Crânio/cirurgia
15.
Clin Neurol Neurosurg ; 203: 106590, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33711640

RESUMO

OBJECTIVE: The relationship between carotid ultrasonographic parameters and postoperative collateral development in adult ischemic moyamoya disease (MMD) patients who received combined direct and indirect revascularization surgery remains unclear. Herein, we investigated the postoperative changes in carotid ultrasonographic parameters in patients with adult ischemic MMD. METHODS: We studied 28 adult ischemic MMD patients (31 hemispheres) who underwent combined revascularization surgery. Patients underwent preoperative and postoperative (within 14 days and 3, 12, and 24 months after surgery) magnetic resonance imaging and carotid ultrasonography. We defined the hemisphere in which all signal intensities of the superficial temporal, middle meningeal, and deep temporal arteries were increased compared with that before surgery on magnetic resonance angiography as well-developed collateral establishment. RESULTS: Patients with good collateral establishment on MRA at 2-year after surgery had a lower external carotid artery (ECA) pulsatility index (PI) (P = 0.0413) and ECA/internal carotid artery (ICA) pulsatility index (PI) ratio (P = 0.0427) at 3-month post-operation. At 3-month post-operation, a cut-off ECA PI of 1.416 (sensitivity 40.0 %, specificity 92.3 %, area under the curve 0.7282, likelihood ratio 5.20, P = 0.0404) and ECA/ICA PI ratio of 0.8768 (sensitivity 50.0 %, specificity 92.31 %, area under the curve 0.7308, likelihood ratio 6.50, P = 0.0415) provided reliable values for good prediction of collateral development at 2 years after revascularization. CONCLUSION: ECA/ICA PI ratio and ECA PI at 3-month after surgery can be one of the indicators for predicting future well-developed neovascularization on MRA and better outcome in patients with adult ischemic MMD who received combined direct and indirect revascularization surgery.


Assuntos
Artéria Carótida Externa/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Revascularização Cerebral , Circulação Colateral , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Adulto , Idoso , Artéria Carótida Externa/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Doença de Moyamoya/fisiopatologia , Valor Preditivo dos Testes , Fluxo Pulsátil , Estudos Retrospectivos , Fatores de Tempo , Ultrassonografia , Adulto Jovem
16.
IEEE Trans Vis Comput Graph ; 27(3): 2041-2055, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31514141

RESUMO

We present a novel method that robustly estimates the reflectance, even in an environment with dynamically changing light. To control the appearance of an object by using a projector-camera system, an appropriate estimate of the object's reflectance is vital to the creation of an appropriate projection image. Most conventional estimation methods assume static light conditions; however, in practice, the appearance is affected by both the reflectance and environmental light. In an environment with dynamically changing light, conventional reflectance estimation methods require calibration every time the conditions change. In contrast, our method requires no additional calibration because it simultaneously estimates both the reflectance and environmental light. Our method is based on the concept of creating two different light conditions by switching the projection at a rate higher than that perceived by the human eye and captures the images of a target object separately under each condition. The reflectance and environmental light are then simultaneously estimated by using the pair of images acquired under these two conditions. We implemented a projector-camera system that switches the projection on and off at 120 Hz. Experiments confirm the robustness of our method when changing the environmental light. Further, our method can robustly estimate the reflectance under practical indoor lighting conditions.

17.
IEEE Trans Vis Comput Graph ; 27(3): 1916-1928, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31613772

RESUMO

We present computational phase-modulated eyeglasses, a see-through optical system that modulates the view of the user using phase-only spatial light modulators (PSLM). A PSLM is a programmable reflective device that can selectively retardate, or delay, the incoming light rays. As a result, a PSLM works as a computational dynamic lens device. We demonstrate our computational phase-modulated eyeglasses with either a single PSLM or dual PSLMs and show that the concept can realize various optical operations including focus correction, bi-focus, image shift, and field of view manipulation, namely optical zoom. Compared to other programmable optics, computational phase-modulated eyeglasses have the advantage in terms of its versatility. In addition, we also presents some prototypical focus-loop applications where the lens is dynamically optimized based on distances of objects observed by a scene camera. We further discuss the implementation, applications but also discuss limitations of the current prototypes and remaining issues that need to be addressed in future research.

18.
No Shinkei Geka ; 48(5): 445-449, 2020 May.
Artigo em Japonês | MEDLINE | ID: mdl-32434956

RESUMO

We report a case of an unruptured aneurysm arising from the bifurcation of the fronto-orbital artery originating from the proximal segment of the left anterior cerebral artery(A1)concurrent with a tuberculum sellae meningioma. A 46-year-old woman presented with a right visual disturbance and left temporal hemianopsia. Preoperative neuroradiological examination showed a heterogeneously enhanced extra-axial suprasellar tumor expanding to the right optic canal and 3-mm diameter aneurysm arising from the bifurcation of the fronto-orbital artery originating from the proximal segment of the left anterior cerebral artery(A1). She underwent total removal of the tumor and neck clipping of the aneurysm via a right pterional approach without any additional deficits. Postoperative MRI and 3D CTA showed total tumor removal and complete obliteration of the aneurysm. The patient was discharged 21 days after surgery without new or worsened postoperative neurological deficits. Cerebral aneurysm concurrent with meningioma is extremely rare. Preoperative diagnosis and appropriate assessment of both the meningioma and unruptured aneurysm are warranted to prevent severe complications.


Assuntos
Aneurisma Intracraniano , Neoplasias Meníngeas , Meningioma , Artéria Cerebral Anterior , Artérias , Feminino , Humanos , Pessoa de Meia-Idade
19.
J Clin Neurosci ; 76: 53-57, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32307301

RESUMO

The relationship between ultrasonographic flow parameters and cognitive function has not been well studied. This study aimed to clarify associations between carotid flow velocity (FV) and cognitive function in patients with a history of carotid endarterectomy (CEA). Ninety-four patients who previously underwent CEA participated in this study. The Neurobehavioral Cognitive Status Examination (Cognistat) and Frontal Assessment Battery (FAB) were adopted to assess cognitive functions at a mean of 6.5 ± 3.2 years after CEA. End-diastolic flow velocity (EDV) of the left and right common carotid artery (CCA) was significantly associated with total Cognistat score (p < 0.001) and total FAB score (p < 0.05). Pulsatility index (PI) of the left CCA was significantly associated with total Cognistat score and total FAB score (p < 0.01). A cut-off right CCA EDV of 14.5 cm/s offered the most reliable predictor of the bottom 25th percentile of total Cognistat score (sensitivity 83.3%, specificity 61.0%, area under the curve (AUC) 0.731, p = 0.0060), while a cut-off left CCA PI of 1.83 was the most reliable predictor of the bottom 25th percentile of total FAB score (sensitivity 73.3%, specificity 60.0%, AUC 0.679, p = 0.0179). Left and right CCA EDV correlated with sub-components of comprehension, construction, judgment, programming (p < 0.01), and conceptualization (p < 0.05). Right CCA EDV correlated with similarity (p < 0.01), repetition, naming, and memory (p < 0.05). Left CCA PI correlated with attention, conceptualization (p < 0.01), repetition, construction, similarity, and mental flexibility (p < 0.05), while right CCA PI correlated with construction (p < 0.05). CCA FV may offer useful markers of cognitive functions in patients with a history of CEA.


Assuntos
Artéria Carótida Primitiva/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Endarterectomia das Carótidas , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Estenose das Carótidas/complicações , Estenose das Carótidas/fisiopatologia , Cognição , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Ultrassonografia Doppler Dupla/métodos
20.
J Clin Neurosci ; 74: 55-60, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31987638

RESUMO

OBJECTIVE: The effects of antithrombotic therapy on chronic subdural hematoma (CSDH) are controversial. Herein, we investigated the association of antithrombotic therapy with surgical complications and outcomes in patients with CSDH. METHODS: We retrospectively analyzed 323 consecutive patients with CSDH who underwent single burr-hole craniostomy. RESULTS: One hundred and eight patients (33%) underwent preoperative antithrombotic therapy. Hemorrhagic and thromboembolic complications were detected in 6 and 8 patients, respectively, which peaked at 3 and 4.5 days after CSDH surgery, respectively. CSDH recurrence was detected in 62 cases, and reoperation was required in 16 cases. Discontinuance of antiplatelet therapy for >2 weeks was significantly associated with thromboembolic complications (43%; p = 0.005). Postoperative use of multiple antithrombotic agents was significantly associated with CSDH recurrence (40%; p = 0.03). Further, earlier recurrence within 2 weeks was significantly associated with the following reoperation (62%; p = 0.006). CONCLUSIONS: To reduce morbidity and minimize the risk of CSDH reoperation, the optimal timing for resumption of antithrombotic agents is approximately 3 days after CSDH surgery. Postoperative use of multiple antithrombotic agents can increase CSDH recurrence, while earlier recurrence may be a predictor for the following reoperation.


Assuntos
Fibrinolíticos/efeitos adversos , Hematoma Subdural Crônico/cirurgia , Tromboembolia/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem , Feminino , Fibrinolíticos/uso terapêutico , Hematoma Subdural Crônico/tratamento farmacológico , Hematoma Subdural Crônico/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Recidiva , Reoperação , Estudos Retrospectivos , Fatores de Tempo , Trepanação/métodos
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