• Title/Summary/Keyword: posterior

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A Case of the Giant Aneurysm in the Distal Portion of the Posterior Cerebral Artery - A Case Report - (후대뇌동맥 원위부에 발생한 거대동맥류 1례 - 증례보고 -)

  • Kim, Jae-Yeoup;Choi, Ha-Young
    • Journal of Korean Neurosurgical Society
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    • v.29 no.7
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    • pp.963-967
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    • 2000
  • The aneurysm arising from the posterior cerebral artery is relatively uncommon, and has been reported in 0.7- 2.2% of whole cerebral aneurysm. Moreover, only a few cases of the giant aneurysm over 2.5cm in diameter arising from the distal portion of the posterior cerebral artery have been reported. Neurologic complications may occur after surgical treatment of this aneurysm due to difficult surgical approach and neurovascular complexity around the brain stem. Authors experienced a case of the thrombosed giant aneurysm with approximately 2.7cm in diameter arising from the P2 segment of the left posterior cerebral artery. Complete removal of the thrombus in the aneurysmal sac and direct neck clipping was performed via left subtemporal approach.

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Thyroid Papillary Carcinoma Presenting as Posterior Pharyngeal Mass : A Case Report (후인두 종물로 나타난 갑상선 유두상 암종 1예)

  • Kang, Jae-Ho;Yang, Si-Chang;Kim, Choon-Dong;Kim, Seung-Woo
    • Korean Journal of Head & Neck Oncology
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    • v.26 no.2
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    • pp.221-224
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    • 2010
  • Papillary thyroid carcinoma frequently invades the lymph node, trachea, esophagus and perithyroid tissue. However, direct extension to posterior pharyngeal area is known to be rare. A 64-year-old male was referred to our clinic presenting as posterior pharyngeal mass during gastrofiberscopy. The neck CT scan showed soft tissue mass in retropharynx and lymph node in right level III with calcifications. We performed the total thyroidectomy with selective(level II, III, IV) and anterior compartment neck dissection. In operative findings, the right thyroid mass were connected to the retropharynx through the posterior portion of inferior constrictor muscle. Histopathologic findings revealed the papillary thyroid carcinoma extended to retropharynx. We report a unique case with a literature review.

A Ruptured Dermoid Cyst of the Cavernous Sinus Extending into the Posterior Fossa

  • Paik, Seung-Chull;Kim, Choong-Hyun;Cheong, Jin-Hwan;Kim, Jae-Min
    • Journal of Korean Neurosurgical Society
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    • v.57 no.5
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    • pp.364-366
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    • 2015
  • Supratentorial dermoid cysts are uncommon to develop in the cavernous sinus. We present a ruptured dermoid cyst of the cavernous sinus extending into the posterior fossa. The patient was a 32-year-old female who complained occipital headache, blurred vision, and tinnitus over 4 years. Brain magnetic resonance (MR) imaging revealed an enhanced tumor in the right cavernous sinus extending into the right temporal base and the posterior fossa with findings of ruptured cyst. Surgical resection was performed, and pathological findings were confirmed to be a dermoid cyst. We report a second case with ruptured dermoid cyst of the cavernous sinus extending into the posterior fossa.

Posterior Consistency for Right Censored Data

  • Lee, Jae-Yong
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.10a
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    • pp.39-45
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    • 2003
  • Ghosh and Ramamoorthi (1996) studied the posterior consistency for survival models and showed that the posterior was consistent, when the prior on the distribution of survival times was the Dirichlet process prior. In this paper, we study the posterior consistency of survival models with neutral to the right process priors which include Dirichlet process priors. A set of sufficient conditions for the posterior consistency with neutral to the right process priors are given. Interestingly, not all the neutral to the right process priors have consistent posteriors, but most of the popular priors such as Dirichlet processes, beta processes and gamma processes have consistent posteriors. For extended beta processes, a necessary and sufficient condition for the consistency is also established.

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Posterior Inference in Single-Index Models

  • Park, Chun-Gun;Yang, Wan-Yeon;Kim, Yeong-Hwa
    • Communications for Statistical Applications and Methods
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    • v.11 no.1
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    • pp.161-168
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    • 2004
  • A single-index model is useful in fields which employ multidimensional regression models. Many methods have been developed in parametric and nonparametric approaches. In this paper, posterior inference is considered and a wavelet series is thought of as a function approximated to a true function in the single-index model. The posterior inference needs a prior distribution for each parameter estimated. A prior distribution of each coefficient of the wavelet series is proposed as a hierarchical distribution. A direction $\beta$ is assumed with a unit vector and affects estimate of the true function. Because of the constraint of the direction, a transformation, a spherical polar coordinate $\theta$, of the direction is required. Since the posterior distribution of the direction is unknown, we apply a Metropolis-Hastings algorithm to generate random samples of the direction. Through a Monte Carlo simulation we investigate estimates of the true function and the direction.

BONE HARVEST FROM POSTERIOR APPROACHES TO THE ILIUM (후방접근법을 이용한 장골채취술)

  • Chang, Se-Hong;Ann, Jae-Jinn;Soh, Jae-Jung
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.12 no.2
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    • pp.88-94
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    • 1990
  • Because of it's accessibility and the quantity of bone available, the ilium is a common donor site for autogenous cancellous, cortical, and corticocancellous grafts to the facial skeleton. Especially, the anterior iliac crest has been the traditional source of pelvic bone for autogenous bone grafting in the maxillofacial skeleton. Recently the need for large amounts of bone in some reconstructive procedures of the facial skeleton has led to the evaluation of posterior ilium. The posterior approach to the ilium is superior to the anterior approach when large quantities of cancellous bone are required for facial reconstruction. The posterior approach has the advantages of more available bone, fewer complications, less postoperative pain, less disturbance in ambulation, and a possible reduction in the length of hospitalization. As the posterior approach affords an almost unlimited amount of bone for autogenous grafting in the maxillofacial region, we feel its use is indicated when very large amounts of bone are required.

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Dissecting Aneurysm Associated with a Double Origin of the Posterior Inferior Cerebellar Artery Causing Subarachnoid Hemorrhage

  • Koh, Jun-Seok;Lee, Cheol-Young;Lee, Seung-Hwan;Kim, Gook-Ki
    • Journal of Korean Neurosurgical Society
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    • v.51 no.1
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    • pp.40-43
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    • 2012
  • Two cases of the posterior fossa dissecting aneurysm associated with a double origin of the posterior inferior cerebellar artery (DOPICA) causing subarachnoid hemorrhage are presented. After observing a relationship between the aneurysm and DOPICA on a three dimensional rotational angiogram (3DRA), the dissecting aneurysms were successfully obliterated by surgical trapping and endovascular internal trapping, respectively. This report warrants suspecting DOPICA of an associating anomaly predisposing to dissecting aneurysm in the vertebral artery-posterior inferior cerebellar artery territory and highlights the role of 3DRA in pretreatment evaluation of unusual aneurysms accompanying a particular anatomical variation.

Posterior Epidural Migration of Thoracic Disc Fragment

  • Kim, Il-Sup;Lee, Sang-Won;Son, Byung-Chul;Sung, Jae-Hoon
    • Journal of Korean Neurosurgical Society
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    • v.43 no.5
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    • pp.239-241
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    • 2008
  • Migration of a disc fragment to the posterior epidural space is rare, especially in the thoracic spine. Only four such cases of posterior epidural migration of thoracic disc fragments have been reported. The authors report a case of 66-year-old man who presented with back pain and right leg weakness due to posterior epidural migration of thoracic disc fragment. The patient was successfully treated by laminectomy and partial facetectomy with disc removal.

Posterior Subtalar Dislocation -1 Case Report - (거골하 관절 후방탈구 - 1례 보고 -)

  • Ym, Soo-Jae;Seo, Woo-Seok
    • Journal of Korean Foot and Ankle Society
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    • v.4 no.1
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    • pp.39-43
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    • 2000
  • A subtalar dislocation of the foot is a dislocation of the talonavicular and talocalcaneal joint while the tibiotalar relationship is unchanged. Posterior subtalar dislocation in particular, is a extremely rare. Only a few cases were reported previously in the literature. We treated a 25 year-old man who sustained the posterior subtalar dislocation in high energy traffic accident. The dislocation of subtalar joint was reduced by closed means with excellent clinical result. In this paper, we report 1 case of posterior dislocation of the subtalar joint and describe the pathomechanics, diagnosis, and treatment.

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Bayesian Multiple Comparisons for Normal Variances

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
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    • v.29 no.2
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    • pp.155-168
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    • 2000
  • Regarding to multiple comparison problem (MCP) of k normal population variances, we suggest a Bayesian method for calculating posterior probabilities for various hypotheses of equality among population variances. This leads to a simple method for obtaining pairwise comparisons of variances in a statistical experiment with a partition on the parameter space induced by equality and inequality relationships among the variances. The method is derived from the fact that certain features of the hierarchical nonparametric family of Dirichlet process priors, in general, make it amenable to solving the MCP and estimating the posterior probabilities by means of posterior simulation, the Gibbs sampling. Two examples are illustrated for the method. For these examples, the method is straightforward for specifying distributionally and to implement computationally, with output readily adapted for required comparison.

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