A high resolution and high contrast MRI for differentiation of subcortical structures for DBS targeting: The Fast Gray Matter Acquisition T1 Inversion Recovery (FGATIR)

NeuroImage ◽  
2009 ◽  
Vol 47 ◽  
pp. T44-T52 ◽  
Author(s):  
Atchar Sudhyadhom ◽  
Ihtsham U. Haq ◽  
Kelly D. Foote ◽  
Michael S. Okun ◽  
Frank J. Bova
Author(s):  
Po Fu Chou ◽  
Li Ming Lu

Abstract Dopant profile inspection is one of the focused ion beam (FIB) physical analysis applications. This paper presents a technique for characterizing P-V dopant regions in silicon by using a FIB methodology. This technique builds on published work for backside FIB navigation, in which n-well contrast is observed. The paper demonstrates that the technique can distinguish both n- and p-type dopant regions. The capability for imaging real sample dopant regions on current fabricated devices is also demonstrated. SEM DC and FIB DC are complementary methodologies for the inspection of dopants. The advantage of the SEM DC method is high resolution and the advantage of FIB DC methodology is high contrast, especially evident in a deep N-well region.


2000 ◽  
Vol 93 (3) ◽  
pp. 498-505 ◽  
Author(s):  
Cole A. Giller ◽  
Maureen Johns ◽  
Hanli Liu

✓ Localization of targets during stereotactic surgery is frequently accomplished by identification of the boundaries between the gray matter of various nuclei and the surrounding white matter. The authors describe an intracranial probe developed for this purpose, which uses near-infrared (NIR) light.The probe fits through standard stereotactic holders and emits light at its tip. The scattered light is detected and analyzed by a spectrometer, with the slope of the trailing portion of the reflectance curve used as the measurement value.Near-infrared readings were obtained during 27 neurosurgical procedures. The first three operations were temporal lobectomies, with values obtained from tracks in the resected specimen and resection bed. In the next five procedures, the probe was inserted stereotactically to a depth of 1 to 2 cm with measurements obtained every 1 mm. The probe was then used in 19 stereotactic procedures for movement disorders, obtaining measurements every 0.5 to 1 mm to target depths of 6 to 8 cm to interrogate subcortical structures. The NIR signals were correlated to distances beneath the cortical surface measured on postoperative computerized tomography or magnetic resonance imaging by using angle correction and three-dimensional reconstruction techniques.The NIR values for white and gray matter obtained during the lobectomies were significantly different (white matter 2.5 ± 0.37, gray matter 0.82 ± 0.23 mean ± standard deviation). The NIR values from the superficial stereotactic tracks showed initial low values corresponding to cortical gray matter and high values corresponding to subcortical white matter.There was good correlation between the NIR signals and postoperative imaging in the 19 stereotactic cases. Dips due to adjacent sulci, a plateau of high signal due to subcortical white matter, a dip in the NIR signal during passage through the ventricle, dips due to the caudate nucleus, and peaks due to the white matter capsule between ventricle and thalamus were constant features. The putamen—capsule boundary and the lamina externa and interna of the globus pallidus could be distinguished in three cases. Elevated signals corresponding to the thalamic floor were seen in 10 cases. Nuances such as prior lesions and nonspecific white matter changes were also detected. There was no incidence of morbidity associated with use of the probe. Data acquisition was straightforward and the equipment required for the studies was inexpensive.The NIR probe described in this article seems to be able to detect gray—white matter boundaries around and within subcortical structures commonly encountered in stereotactic functional neurosurgery. This simple, inexpensive method deserves further study to establish its efficacy for stereotactic localization.


1974 ◽  
Vol 20 (11) ◽  
pp. 1446-1450 ◽  
Author(s):  
Bernard Century ◽  
William P Vorkink ◽  
Samuel Natelson

Abstract We describe a simple, rapid, and inexpensive unidimensional high-resolution thin-layer chromatographic procedure for screening for aminoacidopathies in newborns. Protein-free filtrates are prepared for ultrafiltration of as little as 10 µl of plasma. A rapid, inexpensive photographic method provides large, high-contrast pictures of the chromatograms for permanent records. A day’s samples can be completed in 3 h, including all phases of the procedure.


SINERGI ◽  
2015 ◽  
Vol 19 (3) ◽  
pp. 206
Author(s):  
Nursama Heru Apriantoro ◽  
Christianni Christianni

MRI adalah bagian dari ilmu kedokteran untuk mediagnosa kelainan organ dengan memanfaatkan medan magnet dan pergerakan proton atom hidrogen. Salah satu pemeriksaan MRI adalah pemeriksaan brain. Pemeriksaan MRI brain dapat dilakukan T1 weighted image Spin Echo (T1 SE) atau T1 Fluid Attenuated Inversion Recovery (T1 FLAIR). Kajian dilakukan untuk menentukan perbedaan T1 SE dan T1 FLAIR dari segi citra berdasarkan nilai Rasio Signal terhadap Noise (SNR) dengan MRI GE Type Signa HD xt 1.5 Tesla. Penelitian menggunakan pendekatan kuantitatif.  20 pasien  telah diambil pada pemeriksaan MRI brain pada potongan axial, dengan parameter T1 SE potongan axial dengan parameter Time Repetition (TR) 700 ms, Time Echo (TE) 20 ms, Field of View (FOV) 240 mm, Slice Thickness 5,0 mm, Spacing 1,0 mm, Number of Excitations (NEX) 1, Phase 224, dan total slice 20. T1 FLAIR  parameter TR 3000 ms, TE 13,9 ms, TI 920 ms, FOV 240 mm, slice thickness 5,0 mm, spacing 1,0 mm,   NEX 1, phase 224, dan total slice 20. SNR dihitung pada anatomi brain meliputi CSF (Cerebro Spinal Fluid), White Matter dan Gray Matter. Hasil penelitian kedua sequence tersebut menunjukkan bahwa sequence T1 SE lebih baik daripada sequence T1 FLAIR.


2018 ◽  
Vol 9 (10) ◽  
pp. 2705-2710 ◽  
Author(s):  
Wei Qin ◽  
Pengfei Zhang ◽  
Hui Li ◽  
Jacky W. Y. Lam ◽  
Yuanjing Cai ◽  
...  

A successful strategy for the design of ultrabright red luminogens with aggregation-induced emission (AIE) features is reported. The AIE dots can be utilized as efficient fluorescent probes for in vivo deep-tissue imaging with high penetration depth and high contrast.


2001 ◽  
Vol 1230 ◽  
pp. 1154-1155
Author(s):  
Nobuhiro Tsukamoto ◽  
Hideo Kumagai ◽  
Kiichiro Saitoh ◽  
Masahiko Monma ◽  
Yutaka Ando ◽  
...  

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