• Title/Summary/Keyword: fixation point

Search Result 140, Processing Time 0.028 seconds

A Case of Traumatic Bilateral Abducens Nerve Palsy Associated with Skull Base Fracture (두개저 골절과 동반된 외상성 양측성 외전신경 마비 1례)

  • Hwang, Jeong In;Cho, Jin Seong;Lee, Seung Chul;Lee, Jeong Hun
    • Journal of Trauma and Injury
    • /
    • v.21 no.1
    • /
    • pp.66-69
    • /
    • 2008
  • Traumatic bilateral abducens nerve palsy is rare and is associated with intracranial, skull and cervical spine injuries. We report a case of bilateral abducens nerve palsy in a 40-month-old patient with a skull base fracture. The injury mechanism was associated with direct nerve injury caused by a right petrous bone fracture and indirect injury by frontal impact on the abducens nerve at the point of fixation to the petrous portion and Dorello's canal. The emergency physician should be aware of injuries and the mechanism of abducens nerve palsy in head trauma.

Analysis of the Effect of Mordants on the Degradation of Alizarin in Silk Dyed with Natural Madder Dye

  • Li, Longchun;Ahn, Cheunsoon
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.43 no.2
    • /
    • pp.228-242
    • /
    • 2019
  • This research investigated the effect of mordants on the degradation of madder dye in silk when silk was treated by the H2O2/UV condition as a laboratory simulation of burial induced degradation. Alum, iron, and alum/iron composite mordanting methods were applied to silk before dyeing with madder dye. Dye extracted from silk was examined using HPLC-DAD-MS analysis. The abundance of the chromatogram peak at 8.88 min retention time was used as the concentration of alizarin pigment in silk. K/S values, CIE $L^{\ast}a^{\ast}b^{\ast}$ values; in addition, Munsell HVC values were obtained using a spectrocolorimeter. The findings indicated that alizarin degraded most severely in silk mordanted by alum/iron composite mordanting than alum mordanting or iron mordanting. Mordanting with alum alone provided a relatively lower dye fixation at the point of dyeing; however, it provided a better survival of alizarin after 12 hours of degradation treatment.

Characteristics of Visual Attention for the Different Type of Material Finishing in Cafe Space Using by Eye-tracking (시선추적을 이용한 카페 공간 마감재 차이의 시각주의력 특성)

  • Choi, Jin-Kyung;Kim, Ju-Yeon
    • Korean Institute of Interior Design Journal
    • /
    • v.27 no.2
    • /
    • pp.3-11
    • /
    • 2018
  • This study aims to investigate whether there is intensionally changing eye - gaze on the cafe space images with floor finishing materials. In the Yarbus' experiment, he argued that changing information that an observer is asked to obtain from an image changes pattern of eye movements. Based on the scan path evidence, this research have questions as (1) the difference of visual attention on finishing floor material stimulus, (2) visual attention of initial activity time and type of movement paths on AOIs, and (3) visual relation floor area with another AOIs. Eye movements were recorded with the SMI REDn Scientific, which sampled eye position at 30Hz and lasted 2 minutes(120s). Although viewing was binocular, only the right eye was tracked. Of the 66 observers(mean age 22 years, standard deviation: ${\pm}1.82$) who participated in the experiment done by the four point calibration and validation procedures at the beginning tasks. Analyzing qualitative data from the number of fixation and duration on AOIs divided into four parts (AOI I-Floor, AOI II-Wall, AOI III-Ceiling, and AOI IV-Counter) in the stimulus. The results from this experiment analyzed as follows. First, it was significant in the difference of the average number of AOIs fixation times observed for the spatial image using the wood tile flooring material and the polishing tile. The wood tile flooring of stimulus had higher fixation number on AOI-II, AOI-III, and AOI-IV than the polishing tile. On seeing AOI-I was higher attention in the polishing tile stimulus. Second, the observers examined AOI-II intensively in both stimuli. However, the visual intensity was also followed by on the AOI-IV and AOI-I in the wood tile flooring stimulus, and on AOI-I, AO-IV in the polishing tile. Third, visual attention data on each AOIs have divided into the time range of "5 sec" for both images. In the wood tile stimulus, the horizontal movement path followed by AOI-II, AOI-IV, and AOI-II. In the polished tile stimulus, the movement path followed by moving vertically to AOI-II, AOI-I, and AOI-II. This study approached meaningfully and found out the characteristics of visual attention, according to the different intentions of visual attention, the relationship pathways of visual mechanism appeared and also activated by eye-tracking experiments.

Safe Margin beyond Dens Tips to Ventral Dura in Anterior Odontoid Screw Fixation : Analysis of Three-Dimensional Computed Tomography Scan of Odontoid Process

  • Sung, Min-Jae;Kim, Kyoung-Tae;Hwang, Jeong-Hyun;Sung, Joo-Kyung;Cho, Dae-Chul
    • Journal of Korean Neurosurgical Society
    • /
    • v.61 no.4
    • /
    • pp.503-508
    • /
    • 2018
  • Objective : Anterior odontoid screw fixation is a safe and effective method for the treatment of odontoid fractures. The surgical technique is recommended for perforation of the apical cortex of the dens by the lag screw. However, overpenetration of the apical cortex may lead to potentially serious complications such as damages of adjacent vascular and neural structures. The purpose of this study was to assess the role of three-dimensional computed tomography (CT) scan to evaluate the safe margin beyond dens tip to ventral dura for anterior odontoid screw fixation. Methods : We retrospectively analyzed the three-dimensional CT scans of the cervical spines in 55 consecutive patients at our trauma center. The patients included 38 males and 17 females aged between 22 and 73 years (mean age${\pm}$standard deviation, $45.8{\pm}14.2years$). Using sagittal images of 3-dimensional CT scan, the safe margins beyond dens tip to ventral dura as well as the appropriate screw length were measured. Results : The mean width of the apical dens tip was $9.6{\pm}1.1mm$. The mean lengths from the screw entry point to the apical dens tip and posterior end of dens tip were $39.2{\pm}2.6mm$ and $36.6{\pm}2.4mm$. The safe margin beyond apical dens tip to ventral dura was $7.7{\pm}1.7mm$. However, the safe margin beyond the posterior end of dens tip to ventral dura was decreased to $2.1{\pm}3.2mm$, which was statistically significant (p<0.01). There were no significant differences of safe margins beyond dens tip to ventral dura with patient gender and age. Conclusion : Extension by several millimeters beyond the dens tip is safe, if the trajectory of anterior odontoid screw is targeted at the apical dens tip. However, if the trajectory of the screw is targeted to the posterior end of dens tip, extension beyond dens tip may lead to damage immediately adjacent to the vental dura mater.

Development of A Fractionated Stereotactic Radiotherapy System (분할 정위방사선 치료 시스템 개발 연구)

  • 이동한;지영훈;이동훈;조철구;김미숙;유형준;류성렬
    • Progress in Medical Physics
    • /
    • v.13 no.1
    • /
    • pp.9-14
    • /
    • 2002
  • We invented the newly developed Fractionated Stereotactic Radiotherapy(F.S.R.T) system using combined techniques of couch mounting and pedestal mounting system. Head fixation frame consists of a milled alluminium alloy(duralumin) and is placed to the couch. This frame immobilized patient head using the dental bite, 3.2 mm frontal and occipital thermoplastic mask. To evaluate the coordinate of target isocenter, Brown-Revert-Walls C.T localizer can be attached to this frame. And also, we developed the frame mounting system by developing the modification of pedestal mounting system. This system is fixed to couch floor and can be used to evaluate the isocenteric accuracy of gantry, couch and collimator in Q.A procedure. In order to measure the relocation accuracy, the acrylic phantom and the accurate pointers have been made. The repositioning of the targets in the phantom were estimated by comparing C.T coordinates and E.C.L portal films taken with anterior-posterior and right-left direction. From the results of experiments, the average distance errors between the target isocenter and its mean position were 0.71$\pm$0.19 for lateral, 0.45$\pm$0.15 for inferior-superior, 0.63$\pm$0.18 for anterior-posterior. And the maximum distance error was less than 1.3 mm. The new head fixation frame and frame mounting system were non-invasive, accurately relocatable, easy to use, very light and well tolerable by the results of phantom tests. The major advantage of using this frame mounting system is complete access to any point in the Patients cranium especially posterior direction

  • PDF

Gross, organoleptic and histologic assessment of cadaveric equine heads preserved using chemical methods for veterinary surgical teaching

  • Rodrigo Romero Correa;Rubens Peres Mendes;Diego Darley Velasquez Pineros;Aymara Eduarda De Lima;Andre Luis do Valle De Zoppa;Luis Claudio Lopes Correia da Silva;Ricardo de Francisco Strefezzi;Silvio Henrique de Freitas
    • Journal of Veterinary Science
    • /
    • v.25 no.2
    • /
    • pp.29.1-29.11
    • /
    • 2024
  • Background: Preservation of biological tissues has been used since ancient times. Regardless of the method employed, tissue preservation is thought to be a vital step in veterinary surgery teaching and learning. Objectives: This study was designed to determine the usability of chemically preserved cadaveric equine heads for surgical teaching in veterinary medicine. Methods: Six cadaveric equine heads were collected immediately after death or euthanasia and frozen until fixation. Fixation was achieved by using a hypertonic solution consisting of sodium chloride, sodium nitrite and sodium nitrate, and an alcoholic solution containing ethanol and glycerin. Chemically preserved specimens were stored at low temperatures (2℃ to 6℃) in a conventional refrigerator. The specimens were submitted to gross and organoleptic assessment right after fixative solution injection (D0) and within 10, 20, and 30 days of fixation (D10, D20, and D30, respectively). Samples of tissue from skin, tongue, oral vestibule, and masseter muscle were collected for histological evaluation at the same time points. Results: Physical and organoleptic assessments revealed excellent specimen quality (mean scores higher than 4 on a 5-point scale) in most cases. In some specimens, lower scores (3) were assigned to the range of mouth opening, particularly on D0 and D10. A reduced the range of mouth opening may be a limiting factor in teaching activities involving structures located in the oral cavity. Conclusions: The excellent physical, histologic, and organoleptic characteristics of the specimens in this sample support their usability in teaching within the time frame considered. Appropriate physical and organoleptic characteristics (color, texture, odor, and flexibility) of the specimens in this study support the use of the method described for preparation of reusable anatomical specimens.

Effects of Nitrogen Sources on PRE-point and Free amino acids in Soybean Leaves different In Phosphorus Sensitivity (인산감수성(燐酸感受性)이 다른 대두엽(大豆葉)의 광합성(光合成) 호흡(呼吸) 평형(平衡)과 유리(遊離) 아미노산에 대(對)한 질소원(窒素源)의 영향(影響))

  • Stutte, Charls A.;Park, Hoon
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.6 no.4
    • /
    • pp.239-244
    • /
    • 1973
  • Effects of nitrogen sources on free amino acids, and on photosynthsis-respiration equilibrium point of various positional leaf in soybean were investigated in relation to phosphorus sensitivity. The content of free amino acids was highest in ammonium and lowest in urea treated leaves. Glycine, serine, alanine and especially histidine were high in the ammonium treated leaves. Aspartic acid was high in the nitrate treated leaves. Photosynthesis respiration equilibrium point was higher in the sensitive cultivars, and higher with ammonium than with nitrate. The excess ammonium in plant appears to draw out an intermediate metabolite from carbon fixation pathway resulting in photosynthetic inhibition and activate pentoses phosphate pathway and photorespiration. Such phenomena were likely accentuated in phosphorus sensitive variety.

  • PDF

A Study for the Change of Astigmatism Axis When the Fixation Point Moved Far Distance to Near Distance (원거리에서 근거리 주시 시 난시축 변화에 대한 연구)

  • Joo, Seok-Hee;Sim, Hyun-Seog
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.12 no.2
    • /
    • pp.47-59
    • /
    • 2007
  • When the fixation point moved far distance to near distance, the change of astigmatism type in total astigmatism showed no-changed eyes: 1,020 eyes (63.8%), changed eyes: 578 eyes(36.1 %). The change of with-the-rule into oblique-astigmatism, oblique-astigmatism into with-the-rule, against-the-rule into oblique-astigmatism of change was plenty the most respectively. In corneal astigmatism was no-changed eyes: 1,164 eyes (72.8%), changed eyes: 434 eyes(27.1%). The change of with-the-rule into oblique-astigmatism, oblique-astigmatism into with-the-rule, against-the-rule into with-the-rule astigmatism was plenty the most respectively. In residual astigmatism is no-changed eyes: 935 eyes(58.5%), changed eyes: 663 eyes(41.4%). The change of with-the-rule into oblique-astigmatism, oblique-astigmatism into against-the-rule, against-the-rule into oblique-astigmatism was plenty the most respectively. When the fixation point moved far distance to near distance, the change of astigmatism axis in total astigmatism was no-changed eyes: 761 eyes(48.5%), cyclotorsioned eyes the above 10 degrees: 837 eyes(52.3%). In corneal astigmatism was no-changed eyes: 846 eyes(52.9%), cyclotorsioned eyes the above 10 degrees : 752 eyes(47%). In residual astigmatism was no-changed eyes: 614 eyes(38.4%), cyclotorsioned eyes the above 10 degrees : 984 eyes(62.5%). The magnitude of cyclotorsion of astigmatism axis in total astigmatism was Counter clockwise rotation: 31 degrees, clockwise rotation: 20 degrees. In coneal astigmatism was Counter clockwise rotation: 25 degrees, clockwise rotation: 27 degrees. In residual astigmatism was Counter clockwise rotation: 33 degrees, clockwise rotation: 35 degrees.

  • PDF

A Study for the Change and Distribution of Far Sighted and Near Sighted Astigmatism Power according to Age (연령에 따른 원·근거리 난시의 굴절력 변화에 대한 연구)

  • Joo, Seok-Hee;Park, Seong-Jong
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.12 no.2
    • /
    • pp.25-36
    • /
    • 2007
  • We researched the change of astigmatism power when the fixation point moved from far distance to near distance. Astigmatism power was measured by using both eyes open-view auto-refractometer. We divided the ages between 5 and 67 years old into 12 groups with 1,598 healthy eyes(male-698 eyes and female-900 eyes) without eyes problems and experiences of eyes operations. The mean power in far astigmatism showed that with-the-rule of the total astigmatism: -0.79D, with-the-rule of the corneal astigmatism: -1.07D and against-the-rule of the residual astigmatism : -0.79D were found most respectively. The correlation between cornea astigmatism and total astigmatism was y=0.7493 x + 0.5661 r=0.6510, residual astigmatism and total astigmatism was y=0.248 x - 0.5926 r=0.2598 and corneal astigmatism and residual astigmatism was y=-0.4439 x - 0.1813 r=-0.5551 in the far distance. The mean power in near astigmatism showed that with-the-rule of total astigmatism : -0.92D, with-the-rule of corneal astigmatism : -1.12D, against-the-rule of residual astigmatism : -0.87D were found most respectively. In the near distance, The correlation between corneal astigmatism and total astigmatism was y=0.6872 x + 0.5934 r=0.6204, residual astigmatism and total astigmatism was y=0.303 x - 0.6066 r=0.3165, corneal astigmatism and residual astigmatism was y=-0.46 x - 0.0626 r=-0.5322. When the fixation point moved far distance to near distance, the differences of power according to the type of astigmatism were total astigmatism: $-0.07D{\pm}0.44D$, corneal astigmatism: $-0.04D{\pm}0.54D$ residual astigmatism:$0.01D{\pm}0.53D$. Most of astigmatism refractive power was increased except for oblique-the -astigmatism. When the fixation point moved far distance to near distance, the change of astigmatism refractive power showed total astigmatism: 540 eyes(33.7%), corneal astigmatism: 638 eyes(39.9%), residual: 841 eyes(52.6%).

  • PDF

Comparison of Stereoscopic Fusional Area between People with Good and Poor Stereo Acuity (입체 시력이 양호한 사람과 불량인 사람간의 입체시 융합 가능 영역 비교)

  • Kang, Hyungoo;Hong, Hyungki
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.21 no.1
    • /
    • pp.61-68
    • /
    • 2016
  • Purpose: This study investigated differences in stereoscopic fusional area between those with good and poor stereo acuity in viewing stereoscopic displays. Methods: Stereo acuity of 39 participants (18 males and 21 females, $23.6{\pm}3.15years$) was measured with the random dot stereo butterfly method. Participants with stereo-blindness were not included. Stereoscopic fusional area was measured using stereoscopic stimulus by varying the amount of horizontal disparity in a stereoscopic 3D TV. Participants were divided into two groups of good and poor stereo acuity. Criterion for good stereo acuity was determined as less than 60 arc seconds. Measurements arising from the participants were statistically analyzed. Results: 26 participants were measured to have good stereo acuity and 13 participants poor stereo acuity. In case of the stereoscopic stimulus farther than the fixation point, threshold of horizontal disparity for those with poor stereo acuity were measured to be smaller than the threshold for those with good stereo acuity, with a statistically significant difference. On the other hand, there was no statistically significant difference between the two groups, in case of the stereoscopic stimulus nearer to the fixation point. Conclusions: In viewing stereoscopic displays, the boundary of stereoscopic fusional area for the poor stereo acuity group was smaller than the boundary of good stereo acuity group only for the range behind the display. Hence, in viewing stereoscopic displays, participants with poor stereo acuity would have more difficulty perceiving the fused image at farther distances compared to participants with good stereo acuity.