NON-INVASIVE TECHNIQUE FOR IN VIVO HUMAN EAR CANAL VOLUME MEASUREMENT

2012 ◽  
Vol 12 (04) ◽  
pp. 1250064 ◽  
Author(s):  
JEN-FANG YU ◽  
GO-LONG TSAI ◽  
CHUNG-CHIEH FAN ◽  
CHING-I CHEN ◽  
CHIA-CHI CHENG ◽  
...  
Keyword(s):  
Water Injection ◽  
Three Dimensional ◽  
Volume Measurement ◽  
Invasive Technique ◽  
Slice Thickness ◽  
High Resolution Computed Tomography ◽  
Two Dimensional Image ◽  
Non Invasive ◽  
The Mean

This prospective study is to develop a new non-invasive in vivo technique for the measurement of the human external auditory canal (EAC) volume using high resolution computed tomography (HRCT). Eighteen ears of nine male volunteers, with an age range of 20–30, were measured. The EAC volume was measured using three different methods: tympanometry, water injection, and HRCT. Two dimensional image slices of the EAC, in vivo, were obtained from the raw HRCT data. Each 2D CT image slice was composed of 512 × 512 pixels, with a 0.5 mm slice thickness, and a 0.175 × 0.175 × 0.5 mm3 voxel size. HRCT images were processed with Amira® software (Visage Imaging, Inc., San Diego, USA). Three-dimensional images of the EAC were reconstructed using an unconstrained smoothing mode. The resulting volume of the 3D model of the EAC was calculated using a voxel gate stacked tool. Using tympanometry, the mean measured EAC volume, averaged over all ears, was 766.66 mm3 (Standard Deviation, SD = 194.03 mm3). Using water injection, the mean measured EAC volume was 1102.77mm3 (SD = 121.60 mm3). Using HRCT, the mean measured EAC volume was 1082.22 mm3 (SD = 119.63 mm3). As evident from the SD values, variability was greater in the tympanometry group than in the water injection and HRCT groups. This study successfully developed a new technique to measure the EAC volume using HRCT imaging. This non-invasive technique for in vivo EAC volume measurement was less variable than tympanometry, and avoided the intrusive aspect of measurement by water injection. The technique allows effective, non-invasive assessment of the EAC volume pre-canalplasty, providing a predictor of EAC volume post-canalplasty.

The Measurement of 2D Curvature of In-Vivo Human Ear Canal

2008 ◽  
Vol 139 (2_suppl) ◽  
pp. P103-P103
Author(s):  
Jen-Fang Yu ◽  
Fan Chung-chieh ◽  
Chin-Kuo Chen
Keyword(s):  
3D Model ◽  
External Auditory Meatus ◽  
Slice Thickness ◽  
Inferior Wall ◽  
Ear Canal ◽  
High Resolution Computed Tomography ◽  
Non Invasive ◽  
External Canal ◽  
Human Ear

Problem To non-invasively measure the 2D curvature of human ear canal and produce the earmold by the non-invasive 3D ear impression. Methods The images of external ear were scanned by high-resolution computed tomography (HRCT). The resolution for each slice was 512⋉512 pixels. The pixel size was 0.188⋉0.188mm and the slice thickness was 0.625mm. The boundary between tympanic membrane and external auditory meatus was enhanced by image processing. Additionally, 3D model of ear canal was reconstructed by 2D images. The length and angle of first and second bends of canal were measured based on the 3D model. 2D curvature of first and second bends of canal was then computed by sine and cosine laws. Results The volume of ear canal was 862.0 cubic mm. The angle and curvature of superior wall of first bend at axial view were 121.5 degrees and 0.0685; of inferior wall of first bend were 246 degrees and −0.1102; of superior wall of second bend were 227.8 degrees and −0.0332; of inferior wall of second bend were 143.1 degrees and 0.0130 respectively. 2D curvature of superior and inferior wall of first and second bends was diagrammed. Conclusion The 2D curvature of ear canal at first and second bends could be measured and produce the ear impression non-invasively. The geometry of canal changed by tumors is a common syndrome in ear disease. Therefore, the geometry of ear canal can be tracked after the otoplasty. Significance The 3D geometry of canal can help physicians diagnose the syndrome of external canal before otoplasty. Moreover, the hearing aid earmold can be made by non-invasive ear impression instead of invasive ear impression.

scholarly journals Three-dimensional distribution of CT attenuation in the lumbar spine pedicle wall

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tomoyo Y. Irie ◽  
Tohru Irie ◽  
Alejandro A. Espinoza Orías ◽  
Kazuyuki Segami ◽  
Norimasa Iwasaki ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Age Groups ◽  
Three Dimensional ◽  
Hounsfield Unit ◽  
Lateral Wall ◽  
Ct Attenuation ◽  
Dimensional Distribution ◽  
The Mean ◽  
Pedicle Wall

AbstractThis study investigated in vivo the three-dimensional distribution of CT attenuation in the lumbar spine pedicle wall measured in Hounsfield Unit (HU). Seventy-five volunteers underwent clinical lumbar spine CT scans. Data was analyzed with custom-written software to determine the regional variation in pedicle wall attenuation values. A cylindrical coordinate system oriented along the pedicle’s long axis was used to calculate the pedicular wall attenuation distribution three-dimensionally and the highest attenuation value was identified. The pedicular cross-section was divided into four quadrants: lateral, medial, cranial, and caudal. The mean HU value for each quadrant was calculated for all lumbar spine levels (L1–5). The pedicle wall attenuation was analyzed by gender, age, spinal levels and anatomical quadrant. The mean HU values of the pedicle wall at L1 and L5 were significantly lower than the values between L2–4 in both genders and in both age groups. Furthermore, the medial quadrant showed higher HU values than the lateral quadrant at all levels and the caudal quadrant showed higher HU values at L1–3 and lower HU values at L4–5 than the cranial quadrant. These findings may explain why there is a higher incidence of pedicle screw breach in the pedicle lateral wall.

Magnetresonanzphasenkontrastgeschwindigkeitsmessungen als noninvasive Nachbeobachtungsmaßnahme nach perkutaner transluminaler Angioplastie

VASA ◽  
2002 ◽  
Vol 31 (4) ◽  
pp. 235-240 ◽  
Author(s):  
Heverhagen ◽  
Wagner ◽  
Bandorski ◽  
Hoppe ◽  
Alfke
Keyword(s):  
Phase Contrast ◽  
Ankle Brachial Index ◽  
Transluminal Angioplasty ◽  
Walking Distance ◽  
Slice Thickness ◽  
Non Invasive ◽  
The Mean ◽  
Percutaneous Transluminal ◽  
Phase Contrast Sequence

Background: The aim of this study was to evaluate magnetic resonance phase contrast velocimetry (MRVL) as a non-invasive follow up tool to assess restenosis after percutaneous transluminal angioplasty (PTA). Patients and methods: We prospectively investigated 51 consecutive patients who underwent PTA of the femoropopliteal region. MRVL was conducted prior, one day, six weeks, twelve weeks and 24 weeks after PTA using a circular polarized extremity coil and a gradient echo sequence (TR/TE 600/6 ms, flip angle 30°, slice thickness 10 mm). Hemodynamic data, derived from the MR phase contrast sequence, allowed to calculate the degree of area stenosis of the lesion treated with PTA. These data were correlated with clinical hemodynamic parameters (ankle-brachial index and walking distance). Results: The mean grade of area stenosis was 69% ± 27% before PTA, 30% ± 20% one day, 29% ± 23% six weeks, 39% ± 17% twelve weeks and 42% ± 18% 24 weeks after PTA and correlated well with clinical data and the post angioplasty clinical course of the patients. Conclusions: Follow up measurements using MRVL are suitable to assess restenosis after PTA and allow quantifying the grade of recurrent stenosis as well as the hemodynamic consequences.

scholarly journals Mid-stream clean catch urine collection in newborns: a non-invasive and safe technique

2019 ◽  
Vol 6 (2) ◽  
pp. 349 ◽  
Author(s):  
Rajendra Kumar ◽  
Nithin . ◽  
Sudha Rudrappa
Keyword(s):  
Success Rate ◽  
Urine Sample ◽  
Invasive Technique ◽  
Urine Collection ◽  
Non Invasive ◽  
Invasive Method ◽  
Safe Technique ◽  
The Mean ◽  
Invasive Techniques ◽  
Mean Time

Background: The aim of this study is to determine the success rate and safety of a non-invasive technique to obtain clean-catch midstream urine samples in newborns.Methods: Prospective bedside clinical study. After obtaining written informed consent,120 consecutive newborns admitted in NICU with no dehydration, poor feeding, need for immediate urine sample by invasive method  for whom urine collection was advised for various reasons who met the inclusion criteria were included in the study with consent being taken from the parents. After adequate milk intake supra pubic and lumbar para vertebral areas were stimulated in repeated cycles of 30 s until micturition began.Results: Success rate in obtaining a midstream urine sample within 5 min. The success rate was 90%. The mean time taken to collect urine was 64.24s, for males it was 62.55s and for females 65.93s.Conclusions: The technique has been demonstrated to be safe, quick and effective. The discomfort and time consumption usually associated with bag collection methods as well as invasive techniques can be avoided.

scholarly journals Optical coherence tomography imaging of oral mucosa bullous diseases: a preliminary study

2020 ◽  
Vol 49 (2) ◽  
pp. 20190071
Author(s):  
Dario Di Stasio ◽  
Dorina Lauritano ◽  
Francesca Loffredo ◽  
Enrica Gentile ◽  
Fedora Della Vella ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Oral Mucosa ◽  
Statistical Power ◽  
Pemphigus Vulgaris ◽  
Invasive Technique ◽  
Optical Coherence ◽  
Non Invasive ◽  
Bullous Diseases ◽  
Subepithelial Layer

Objectives: Optical coherence tomography (OCT) is a non-invasive technique based on optical imaging with a micrometre resolution. The purpose of this study is to investigate the potential role of OCT in evaluating oral mucosa bullous diseases. Methods: two patients with bullous pemphigoid (BP) and one patient with pemphigus vulgaris (PV) were examined and images of their oral lesions were performed using OCT. Results: In OCT images, the BP blister has a clearly different morphology from the PV one compared to the blistering level. Conclusion: This exploratory study suggests that the OCT is able to distinguish epithelial and subepithelial layer in vivo images of healthy oral mucosa from those with bullous diseases, assisting the clinicians in differential diagnosis.The presented data are in accordance with the scientific literature, although a wider pool of cases is needed to increase statistical power. Histological examination and immunofluorescence methods remain the gold standard for the diagnosis of oral bullous diseases. In this context, the OCT can provide the clinician with a valuable aid both as an additional diagnostic tool and in the follow up of the disease.

scholarly journals Confocal Raman spectroscopy: Evaluation of a non-invasive technique for the detection of topically applied ketorolac tromethamine in vitro and in vivo

2019 ◽  
Vol 570 ◽  
pp. 118641 ◽  
Author(s):  
Christian J.F. Bertens ◽  
Shuo Zhang ◽  
Roel J. Erckens ◽  
Frank J.H.M. van den Biggelaar ◽  
Tos T.J.M. Berendschot ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Invasive Technique ◽  
Ketorolac Tromethamine ◽  
Confocal Raman Spectroscopy ◽  
Non Invasive ◽  
Confocal Raman

scholarly journals Method for Calibration of Left Ventricle Material Properties Using Three-Dimensional Echocardiography Endocardial Strains

2019 ◽  
Vol 141 (9) ◽  
Author(s):  
Yaghoub Dabiri ◽  
Kevin L. Sack ◽  
Nuno Rebelo ◽  
Peter Wang ◽  
Yunjie Wang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Left Ventricle ◽  
Diffusion Tensor ◽  
Diastolic Pressure ◽  
Three Dimensional ◽  
Heart Association ◽  
Mean Difference ◽  
Imaging Data ◽  
The Mean

We sought to calibrate mechanical properties of left ventricle (LV) based on three-dimensional (3D) speckle tracking echocardiographic imaging data recorded from 16 segments defined by American Heart Association (AHA). The in vivo data were used to create finite element (FE) LV and biventricular (BV) models. The orientation of the fibers in the LV model was rule based, but diffusion tensor magnetic resonance imaging (MRI) data were used for the fiber directions in the BV model. A nonlinear fiber-reinforced constitutive equation was used to describe the passive behavior of the myocardium, whereas the active tension was described by a model based on tissue contraction (Tmax). isight was used for optimization, which used abaqus as the forward solver (Simulia, Providence, RI). The calibration of passive properties based on the end diastolic pressure volume relation (EDPVR) curve resulted in relatively good agreement (mean error = −0.04 ml). The difference between the experimental and computational strains decreased after segmental strain metrics, rather than global metrics, were used for calibration: for the LV model, the mean difference reduced from 0.129 to 0.046 (circumferential) and from 0.076 to 0.059 (longitudinal); for the BV model, the mean difference nearly did not change in the circumferential direction (0.061) but reduced in the longitudinal direction from 0.076 to 0.055. The calibration of mechanical properties for myocardium can be improved using segmental strain metrics. The importance of realistic fiber orientation and geometry for modeling of the LV was shown.

Comparing microsphere deposition and flow modeling in 3D vascular trees

2006 ◽  
Vol 291 (5) ◽  
pp. H2136-H2141 ◽  
Author(s):  
M. Marxen ◽  
J. G. Sled ◽  
L. X. Yu ◽  
C. Paget ◽  
R. M. Henkelman
Keyword(s):  
Flow Model ◽  
Three Dimensional ◽  
Blood Perfusion ◽  
Relative Dispersion ◽  
Vascular Structure ◽  
Vascular Tree ◽  
High Resolution Computed Tomography ◽  
Arterial Tree ◽  
Pipe Model

Blood perfusion in organs has been shown to be heterogeneous in a number of cases. At the same time, a number of models of vascular structure and flow have been proposed that also generate heterogeneous perfusion. Although a relationship between local perfusion and vascular structure has to exist, no model has yet been validated as an accurate description of this relationship. A study of perfusion and three-dimensional (3D) arterial structure in individual rat kidneys is presented, which allows comparison between local measurements of perfusion and model-based predictions. High-resolution computed tomography is used to obtain images of both deposited microspheres and of an arterial cast in the same organ. Microsphere deposition is used as an estimate of local perfusion. A 3D cylindrical pipe model of the arterial tree is generated based on an image of the arterial cast. Results of a flow model are compared with local microsphere deposition. High correlation ( r2 > 0.94) was observed between measured and modeled flows through the vascular tree segments. However, the relative dispersion of the microsphere perfusion measurement was two- to threefold higher than perfusion heterogeneity calculated in the flow model. Also, there was no correlation in the residual deviations between the methods. This study illustrates the importance of comparing models of local perfusion with in vivo measurements of perfusion in the same biologically realistic vascular tree.

Three-dimensional reconstruction based on images from spiral high-resolution computed tomography of the temporal bone: anatomy and clinical application

2005 ◽  
Vol 119 (9) ◽  
pp. 693-698 ◽  
Author(s):  
Beom-Cho Jun ◽  
Sun-Wha Song ◽  
Ju-Eun Cho ◽  
Chan-Soon Park ◽  
Dong-Hee Lee ◽  
...  
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
3D Reconstruction ◽  
Temporal Bone ◽  
Three Dimensional ◽  
Image Data ◽  
Computer Assisted ◽  
Surface Rendering ◽  
High Resolution Computed Tomography

The aim of this study was to investigate the usefulness of a three-dimensional (3D) reconstruction of computed tomography (CT) images in determining the anatomy and topographic relationship between various important structures. Using 40 ears from 20 patients with various otological diseases, a 3D reconstruction based on the image data from spiral high-resolution CT was performed by segmentation, volume-rendering and surface-rendering algorithms on a personal computer. The 3D display of the middle and inner ear structures was demonstrated in detail. Computer-assisted measurements, many of which could not be easily measured in vivo, of the reconstructed structures provided accurate anatomic details that improved the surgeon’s understanding of spatial relationships. A 3D reconstruction of temporal bone CT might be useful for education and increasing understanding of the anatomical structures of the temporal bone. However, it will be necessary to confirm the correlation between the 3D reconstructed images and histological sections through a validation study.

scholarly journals In vivo contactless brain stimulation via non-invasive and targeted delivery of magnetoelectric nanoparticles

2020 ◽  
Author(s):  
Tyler Nguyen ◽  
Jianhua Gao ◽  
Ping Wang ◽  
Abhignyan Nagesetti ◽  
Peter Andrews ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Brain Stimulation ◽  
Targeted Delivery ◽  
Brain Region ◽  
Magnetic Field Gradient ◽  
Latency Period ◽  
Global Network ◽  
Invasive Technique ◽  
Non Invasive

AbstractNon-invasive brain stimulation is valuable for studying neural circuits and treating various neurological disorders in humans. However, the current technologies usually have low spatial and temporal precision and poor brain penetration, which greatly limit their application. A new class of nanoparticles known as magneto-electric nanoparticles (MENs) can be navigated to a targeted brain region with a magnetic field and is highly efficient in converting an externally applied magnetic wave into local electric fields for neuronal activity modulation. Here we developed a new method to fabricate MENs of CoFe2O4-BaTiO3 core-shell structure that had excellent magneto-electrical coupling properties. Using calcium imaging of organotypic and acute cortical slices from GCaMP6s transgenic mice, we demonstrated their efficacy in reliably evoking neuronal responses with a short latency period. For in vivo non-invasive delivery of MENs to brain, fluorescently labeled MENs were intravenously injected and guided to pass through the blood brain barrier to a targeted brain region by applying a magnetic field gradient. A magnetic field (∼450 Oe at 10 Hz) applied to mouse brain was able to reliably evoke cortical activities, as revealed by in vivo two-photon and mesoscopic imaging of calcium signals at both cellular and global network levels. The effect was further confirmed by the increased number of c-Fos expressing cells after stimulation. Neither brain delivery of MENs nor the subsequent magnetic stimulation caused any significant increases in the numbers of GFAP and IBA1 positive astrocytes and microglia in the brain. This study demonstrates the feasibility of using MENs as a novel efficient and non-invasive technique of contactless deep brain stimulation that may have great potential for translation.

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