• 제목/요약/키워드: optic nerve

검색결과 150건 처리시간 0.029초

Basic requirements for visual evoked potentials

  • Seok, Hung Youl;Lee, Eun-Mi;Park, Kee Duk;Seo, Dae-Won;Korean Society of Clinical Neurophysiology Education Committee
    • Annals of Clinical Neurophysiology
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    • 제20권1호
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    • pp.12-17
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    • 2018
  • Visual evoked potentials (VEPs) are frequently used to assess the anterior and posterior visual pathways. In particular, the use of VEPs have been increasing in various fields such as evaluation of the optic nerves in patients with multiple sclerosis. The performance of VEP test can be affected by various factors such as stimulus type and subject condition, and its interpretation is also difficult. However, there have been no guidelines for performing and interpreting VEPs in Korea. Therefore, we aimed to provide comprehensive information regarding basic requirement and interpretation for VEPs.

유전성대사질환에서 눈이상 (Inherited Metabolic Disorders Involving the Eye)

  • 정재호
    • 대한유전성대사질환학회지
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    • 제22권2호
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    • pp.37-45
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    • 2022
  • Inherited metabolic disorders (IMD) are a large group of rare disorders affecting normal biochemical pathways. The ophthalmic involvement can be very varied affecting any part of the eye, including abnormalities of cornea, lens dislocation and cataracts, retina and the optic nerve, and extraocular muscles. Eye disorders can be initial symptoms of some IMD and can be clue for diagnosis of IMD. However, eye disorders can evolve later in the natural history of an already diagnosed metabolic disorder. Awareness of IMDs is important to facilitate early diagnosis and in some cases instigate early treatment if a patient presents with eye involvement suggestive of a metabolic disorder. Ophthalmological interventions are also an important component of the multisystem holistic approach to treating patients with metabolic disorders.

Assessment of Posterior Globe Flattening: Two-Dimensional versus Three-Dimensional T2-Weighted Imaging

  • Ann, Jun Hyung;Kim, Eung Yeop
    • Investigative Magnetic Resonance Imaging
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    • 제19권3호
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    • pp.178-185
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    • 2015
  • Purpose: To compare the frequency of posterior globe flattening between two-dimensional T2-weighted imaging (2D T2WI) and three-dimensional (3D T2WI). Materials and Methods: Sixty-nine patients (31 female; mean age, 44.4 years) who had undergone both 5-mm axial T2WI and sagittal 3D 1-mm isovoxel T2WI of the whole brain for evaluation of various diseases (headache [n = 30], large hemorrhage [n = 19], large tumor or leptomeningeal tumor spread [n = 15], large infarct [n = 3], and bacterial meningitis [n = 2]) were used in this study. Two radiologists independently reviewed both sets of images at separate sessions. Axial T2WI and multi-planar imaging of 3D T2WI were visually assessed for the presence of globe flattening. The optic nerve sheath diameter (ONSD) was measured at a location 4 mm posterior to each globe on oblique coronal imaging reformatted from 3D T2WI. Results: There were significantly more globes showing posterior flattening on 3D T2WI (105/138 [76.1%]) than on 2D T2WI (27/138 [19.6%], P = 0.001). Inter-observer agreement was excellent for both 2D T2WI and 3D T2WI (Cohen's kappa = 0.928 and 0.962, respectively). Intra-class correlation coefficient for the ONSD was almost perfect (Cohen's kappa = 0.839). The globes with posterior flattening had significantly larger ONSD than those without on both 2D and 3D T2WI (P < 0.001; $6.14mm{\pm}0.44$ vs. $5.74mm{\pm}0.44$ on 2D T2WI; $5.90mm{\pm}0.47$ vs. $5.56mm{\pm}0.34$ on 3D T2WI). Optic nerve protrusion was significantly more frequent on reformatted 1-mm 3D T2WI than on 5-mm 2D T2WI (8 out of 138 globes on 3D T2WI versus one on 2D T2WI; P = 0.018). Conclusion: Posterior globe flattening is more frequently observed on 3D T2WI than on 2D T2WI in patients suspected of having increased intracranial pressure. The globes with posterior flattening have significantly larger ONSD than those without.

Correlation between Optic Nerve Sheath Diameter Measured by Computed Tomography and Elevated Intracranial Pressure in Patients with Traumatic Brain Injury

  • Lim, Tae Kyoo;Yu, Byug Chul;Ma, Dae Sung;Lee, Gil Jae;Lee, Min A;Hyun, Sung Yeol;Jeon, Yang Bin;Choi, Kang Kook
    • Journal of Trauma and Injury
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    • 제30권4호
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    • pp.140-144
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    • 2017
  • Purpose: The optic nerve sheath diameter (ONSD) measured by ultrasonography is among the indicators of intracranial pressure (ICP) elevation. However, whether ONSD measurement is useful for initial treatment remains controversial. Thus, this study aimed to investigate the relationship between ONSD measured by computed tomography (CT) and ICP in patients with traumatic brain injury (TBI). Methods: A total of 246 patients with severe trauma from January 1, 2015 until December 31, 2015 were included in the study. A total of 179 patients with brain damage with potential for ICP elevation were included in the TBI group. The remaining 67 patients comprised the non-TBI group. A comparison was made between the two groups. Receiver operating characteristic (ROC) curve analysis was performed to determine the accuracy of ONSD when used as a screening test for the TBI group including those with TBI with midline shift (with elevated ICP). Results: The mean injury severity score (ISS) and glasgow coma scale (GCS) of all patients were $24.2{\pm}6.1$ and $5.4{\pm}0.8$, respectively. The mean ONSD of the TBI group ($5.5{\pm}1.0mm$) was higher than that of the non-TBI group ($4.7{\pm}0.6mm$). Some significant differences in age ($55.3{\pm}18.1$ vs. $49.0{\pm}14.8$, p<0.001), GCS ($11.7{\pm}4.1$ versus $13.3{\pm}3.0$, p<0.001), and ONSD ($5.5{\pm}1.0$ vs. $4.7{\pm}0.6$, p<0.001) were observed between the TBI and the non-TBI group. An ROC analysis was used to assess the correlation between TBI and ONSD. Results showed an area under the ROC curve (AUC) value of 0.752. The same analysis was used in the TBI with midline shift group, which showed an AUC of 0.912. Conclusions: An ONSD of >5.5 mm, measured on CT, is a good indicator of ICP elevation. However, since an ONSD is not sensitive enough to detect an increased ICP, it should only be used as one of the parameters in detecting ICP along with other screening tests.

한국 연근해산 두족류 (Todarodes pacificus and Octopus minor) 시엽 (Optic lobe)의 미세구조 (Fine Structure of Optic Lobes of Cephalopods (Todarodes pacificus and Octopus minor) inhabiting the Korean Waters)

  • 한종민;장남섭
    • Applied Microscopy
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    • 제32권2호
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    • pp.131-147
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    • 2002
  • 살오징어와 서해낙지의 시엽은 피질부와 수질부로 크게 나눌 수 있었고, 피질부는 3층(외과립세포층, 망상층, 그리고 내과립세포층)으로 구성되어 있었다. 피질부의 두께는 오징어에서 약 $420{\sim}450{\mu}m$ (외과립층, $100{\mu}m$; 망상층, $170{\sim}200{\mu}m$ 그리고 내과립층, $150{\mu}m$) 정도였고 낙지인 경우는 약 $250{\sim}290{\mu}m$ (외과립세포층, $50{\sim}70{\mu}m$; 망상층, $100{\sim}120{\mu}m$; 내과립세포층, $100{\mu}m$) 정도로 관찰되어 오징어가 낙지에 비해 $170{\mu}m$ 정도 더 두터웠다. 살오징어의 외과립세포층에서는 3종류의 신경세포(A형, B형 그리고 C형)와 이들을 감싸거나 인접되어 있는 신경교세포들이 관찰되었고, 서해낙지에서는 2종류의 신경세포(A형과 B형)와 1종류의 신경교세포가 관찰되었다. 망상층에는 전연접자루와 신경말단들이 서로 연접되어 다양한 형태의 연접체를 형성하였는데, 살오징어에서는 전자밀도가 높은 소포, 과립소포, 그리고 투명소포 등이 혼재되어 있거나 한 종류만을 포함하는 경우 등 다양한 반면, 서해낙지에서는 투명소포만을 소지한 경우와 과립소포만을 소지한 경우, 그리고 투명소포와 과립소포들이 혼합된 경우 등 3종류의 연접체가 주로 관찰되었다. 내과립세포층은 구조적으로 두 종에서 거의 비슷한 형태이며 2종류의 신경세포(A형과 B형)와 1종류의 신경교세포로 구성되어 있었다. 살오징어의 수질부에서는 크기가 $7{\times}5{\mu}m$ 정도인 세포들이 일렬로 배열되어 있어 울타리세포층을 형성하였으나 서해낙지에서는 이들이 관찰되지 않았다.

가교된 Poly(2-hydroxyethyl methacrylate)로 부터의 5-Fluorouracil의 방출성 (Controlled Release of 5-Fluorouracil from Crosslinked Poly(2-hydroxyethyl methacrylate))

  • 조종수;정숙자;이강춘
    • 대한의용생체공학회:의공학회지
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    • 제10권2호
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    • pp.191-194
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    • 1989
  • A new neural network architecture for the recognition of patterns from images is proposed, which is partially based on the results of physiological studies. The proposed network is composed of multi-layers and the nerve cells in each layer are connected by spatial filters which approximate receptive fields in optic nerve fields. In the proposed method, patterns recognition for complicated images is carried out using global features as well as local features such as lines and end-points. A new generating method of matched filers representing global features is proposed in this network.

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기관에 발생한 신경초종 1예 (A Case of Tracheal Schwannoma)

  • 이한빈;장재원;신유섭;김철호
    • 대한기관식도과학회지
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    • 제18권1호
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    • pp.24-26
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    • 2012
  • As benign tumor originating in Schwann cells of nerve sheath, Schwannoma can rise in any site involving cranial nerve, sympathetic nerves, peripheral nerves excepting optic nerves and olfactory nerves. Schwannoma rarely occurs in trachea, and although can appear in any part, most often seen in the lower third of the trachea. Here, we reported a case of intra-tracheal schwannoma misdiagnosed and treated as bronchial asthma, later identified and successfully excised through an external approach.

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Ganglioglioma in Brainstem : Case Report and a Review of Literatures

  • Kim, Sung-Duk;Kim, Jong Hyun;Lee, Cheol-Young;Kim, Hyun-Woo
    • Journal of Korean Neurosurgical Society
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    • 제55권3호
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    • pp.164-166
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    • 2014
  • Ganglioglioma is an infrequent tumor of the central nervous system (CNS); mostly supratentorial region. But, they can occur anywhere in the central nervous system such as brainstem, cerebellopontine angle (CPA), thalamus, optic nerve and spinal cord. Although it occurs rarely, ganglioglioma should be included in the differential diagnosis of a posterior fossa mass because early recognition is important for treatment and patient counseling.

Alveolar bone necrosis and spontaneous tooth exfoliation associated with trigeminal herpes zoster: a report of three cases

  • Kim, Nam-Kyoo;Kim, Bong-Chul;Nam, Jung-Woo;Kim, Hyung-Jun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제38권3호
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    • pp.177-183
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    • 2012
  • Herpes zoster is a viral infection caused by the reactivation of the varicella zoster virus, an infection most commonly affecting the thoracolumbar trunk. Herpes Zoster Infection (HZI) may affect the cranial nerves, most frequently the trigeminal. HZI of the trigeminal nerve distribution network manifests as multiple, painful vesicular eruptions of the skin and mucosa which are innervated by the infected nerves. Oral vesicles usually appear after the skin manifestations. The vesicles rupture and coalesce, leaving mucosal erosions without subsequent scarring in most cases. The worst complication of HZI is post-herpetic neuralgia; other complications include facial scarring, motor nerve palsy and optic neuropathy. Osteonecrosis with spontaneous exfoliation of the teeth is an uncommon complication associated with HZI of the trigeminal nerve. We report several cases of osteomyelitis appearing on the mandible, caused by HZI, and triggering osteonecrosis or spontaneous tooth exfoliation.

도룡뇽(Hynobius leechi)의 시각계 발생 (Development of Visual System in Korean Salamander(Hynobius leechi))

  • 정선우;윤춘식;김덕훈
    • 한국안광학회지
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    • 제3권1호
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    • pp.9-13
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    • 1998
  • 한국산 도룡농 Hynobius leechi의 시각계발생을 형태학적으로 연구하였다. 수정란을 채집하여 멸균된 생리식염수에서 발생시키고 5-30mm길이의 유생을 크기별로 하였다. 표본은 paraffin에 포매하고 절편하여 광학현미경하에서 관찰하였다. 5mm유생에서, 안배에 의해 유도된 수정체의 원기는 감각외 배엽과 결함되어 있었다. 12mm유생은 수정체가 구형으로 되고 색소상피가 뚜렷해지나 망막층의 분화는 일어나지 않았다. 14-16mm유생은 망막층의 분화가 뚜렷해지며 수정체의 중심부섬유의 핵이 붕괴되었다. 20mm유생의 안배의 외연부는 얇아져서 홍채와 모양체를 형성하였다. 30mm유생에서는 맥락막이 두터워지고 연골이 안구의 외곽에서도 나타났다. 광수용세포층의 외절은 점차로 길게 성장하고 안구신경은 연골을 지나 뇌의 복측에 연결된다.

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