Hee Seung Noh;Sung Chan Park;Jong Min Lee;Soon Chan Kwon
Journal of Cerebrovascular and Endovascular Neurosurgery
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v.25
no.2
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pp.196-202
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2023
One of the common complications that can occur during coil embolization of cerebral aneurysms, is migration of coil lump alone. The removal of these migrated coils has been reported on a few occasions. On the other hand, rare complications would include the migration of the coil with subsequent stent dislocation. Currently, there is no standardized method to correct the complications of stent dislocation, and very few instances of this complication have been reported previously. In this report, we introduce a case of coil migration combined with stent dislocation. This occurred during coil embolization of an unruptured aneurysm of the distal, left internal carotid artery for a 52-year old woman. We retrieved both the damaged stent and migrated coil using another retrievable stent successfully with no more further complications. In the present report, we describe in detail how we corrected the complication successfully stent, and we discuss why this rescue maneuver is reasonable option for the complication mentioned above.
Background: Off-pump coronary artery bypass grafting (OPCAB) shows fewer side effects than cardiopulmonary by. pass, and other benefits include myocardial protection, pulmonary and renal protection, coagulation, inflammation, and cognitive function. We analyzed the clinical results of our cases of OPCAB. Material and Method: From May 1999 to August 2007, OPCAB was performed in 100 patients out of a total of 310 coronary artery bypass surgeries. There were 63 males and 37 females, from 29 to 82 years old, with a mean age of $62{\pm}10$ years. The preoperative diagnoses were unstable angina in 77 cases, stable angina in 16, and acute myocardial infarction in 7. The associated diseases were hypertension in 48 cases, diabetes in 42, chronic renal failure in 10, carotid artery disease in 6, and chronic obstructive pulmonary disease in 5. The preoperative cardiac ejection fraction ranged from 26% to 74% (mean $56.7{\pm}11.6%$). Preoperative angiograms showed three-vessel disease in 47 cases, two-vessel disease in 25, one-vessel disease in 24, and left main disease in 23. The internal thoracic artery was harvested by the pedicled technique through a median sternotomy in 97 cases. The radial artery and greater saphenous vein were harvested in 70 and 45 cases, respectively (endoscopic harvest in 53 and 41 cases, respectively). Result: The mean number of grafts was $2.7{\pm}1.2$ per patient, with grafts sourced from the unilateral internal thoracic artery in 95 (95%) cases, the radial artery in 62, the greater saphenous vein in 39, and the bilateral internal thoracic artery in 2. Sequential anastomoses were performed in 46 cases. The anastomosed vessels were the left anterior descending artery in 97 cases, the obtuse marginal branch in 63, the diagonal branch in 53, the right coronary artery in 30, the intermediate branch in 11, the posterior descending artery in 9 and the posterior lateral branch in 3. The conversion to cardiopulmonary bypass occurred in 4 cases. Graft patency was checked before discharge by coronary angiography or multi-slice coronary CT angiography in 72 cases, with a patency rate of 92.9% (184/198). There was one case of mortality due to sepsis. Postoperative arrhythmias or myocardial in-farctions were not observed. Postoperative complications were a cerebral stroke in 1 case and wound infection in 1. The mean time of respirator care was $20{\pm}35$ hours and the mean duration of stay in the intensive care unit was $68{\pm}47$ hours. The mean amounts of blood transfusion were $4.0{\pm}2.6$ packs/patient. Conclusion: We found good clinical outcomes after OPCAB, and suggest that OPCAB could be used to expand the use of coronary artery bypass grafting.
Seo, Won-Duck;Kim, Young-Don;Hong, Dae-Young;Kim, Dae-Hyun;Choi, Gi-Hwan;Yeo, Hyung-Tae
Journal of Korean Neurosurgical Society
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v.40
no.6
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pp.434-440
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2006
Objective : The purpose of this study is to examine the influence of cranioplasty on dynamics of cerebral blood flow[CBF] and cerebrovascular reserve capacity[CVRC], and to investigate the usefulness of single photon emission computed tomography [SPECT] as a prognostic factor for neurological improvement after cranioplasty. Methods : Between March 2003 and December 2005, a prospective study was performed on 24 patients who had undergone total 25 cranioplasty operations. Cerebral blood flow velocities in the middle cerebral artery[MCA] and internal carotid artery[ICA] were obtained by transcranial Doppler ultrasonography[TCD]. The CVRC was assessed by SPECT in the natural state and after stimulation with 1g of acetazolamide. Neurological improvement after cranioplasty was compared between patients who showed hyperactivity to acetazolamide-activated SPECT [Group 1, n=7] and hypoactivity to acetazolamide-activated SPECT [Group 2, n=17]. These measurements were obtained two weeks prior to and two weeks after cranioplasty. Results : The blood flow velocities at the opposite site to the cranioplasty as well as at the cranioplasty site were significantly increased [P<0.05]. Compared with Group 2, there was significant increase in CBF and neurological improvement after cranioplasty in Group 1. Conclusion : Among patients with surgical bony defects, the patients who had normal reactivity of the CVRC showed a significant increase in CBF and neurological improvement after cranioplasty. The authors suggest that CVRC measurement prior to surgery may be an important prognostic factor for neurological improvement after cranioplasty.
Song, Seung Yoon;Ahn, Seong Yeol;Rhee, Jong Ju;Lee, Jong Won;Hur, Jin Woo;Lee, Hyun Koo
Journal of Korean Neurosurgical Society
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v.58
no.4
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pp.321-327
/
2015
Objective : To determine whether the use of contrast enhancement (especially its extent) predicts malignant brain edema after intra-arterial thrombectomy (IAT) in patients with acute ischemic stroke. Methods : We reviewed the records of patients with acute ischemic stroke who underwent IAT for occlusion of the internal carotid artery or the middle cerebral artery between January 2012 and March 2015. To estimate the extent of contrast enhancement (CE), we used the contrast enhancement area ratio (CEAR)-i.e., the ratio of the CE to the area of the hemisphere, as noted on immediate non-enhanced brain computed tomography (NECT) post-IAT. Patients were categorized into two groups based on the CEAR values being either greater than or less than 0.2. Results : A total of 39 patients were included. Contrast enhancement was found in 26 patients (66.7%). In this subgroup, the CEAR was greater than 0.2 in 7 patients (18%) and less than 0.2 in the other 19 patients (48.7%). On univariate analysis, both CEAR ${\geq}0.2$ and the presence of subarachnoid hemorrhage were significantly associated with progression to malignant brain edema (p<0.001 and p=0.004), but on multivariate analysis, only CEAR ${\geq}0.2$ showed a statistically significant association (p=0.019). In the group with CEAR ${\geq}0.2$, the time to malignant brain edema was shorter (p=0.039) than in the group with CEAR <0.2. Clinical functional outcomes, based on the modified Rankin scale, were also significantly worse in patients with CEAR ${\geq}0.2$ (p=0.003) Conclusion : The extent of contrast enhancement as noted on NECT scans obtained immediately after IAT could be predictive of malignant brain edema and a poor clinical outcome.
Yoon, Byul Hee;Kim, Han Kyu;Park, Mun Sun;Kim, Seong Min;Chung, Seung Young;Lanzino, Giuseppe
Journal of Korean Neurosurgical Society
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v.52
no.4
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pp.391-395
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2012
Objective : Removal of the anterior clinoid process (ACP) is an essential process in the surgery of giant or complex aneurysms located near the proximal internal carotid artery or the distal basilar artery. An extradural clinoidectomy must be performed within the limits of the meningeal layers surrounding the ACP to prevent morbid complications. To identify the safest method of extradural exposure of the ACP, anatomical studies were done on cadaver heads. Methods : Anatomical dissections for extradural exposure of the ACP were performed on both sides of seven cadavers. Before dividing the frontotemporal dural fold (FTDF), we measured its length from the superomedial apex attached to the periorbita to the posterolateral apex which connects to the anterosuperior end of the cavernous sinus. Results : The average length of the FTDF on cadaver dissections was 7 mm on the right side and 7.14 mm on the left side. Cranial nerves were usually exposed when cutting FTDF more than 7 mm of the FTDF. Conclusion : The most delicate area in an extradural anterior clinoidectomy is the junction of the FTDF and the anterior triangular apex of the cavernous sinus. The FTDF must be cut from the anterior side of the triangle at the periorbital side rather than from the dural side. The length of the FTDF incision must not exceed 7 mm to avoid cranial nerve injury.
Kim, Sung Tae;Jin, Sung-Chul;Jeong, Hae Woong;Seo, Jung Hwa;Ha, Sam Yeol;Pyun, Hae Wook
Journal of Korean Neurosurgical Society
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v.56
no.6
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pp.463-468
/
2014
Objective : Unexpected Solitaire stent detachment can occur during mechanical Solitaire thrombectomy. The purpose of this study was to retrospectively evaluate the influencing factors causing unexpected Solitaire stent detachment and the clinical outcomes. Methods : Between October 2011 to December 2013, 232 cases of mechanical Solitaire thrombectomy for acute ischemic stroke were performed in 3 stroke centers. During this period, we encountered unexpected Solitaire stent detachments during mechanical Solitaire thrombectomies in 9 cases. Results : Solitaire stents unexpectedly detached in 9 cases (3.9%) during the retrieval of Solitaire stents. The median patient age was 76 years. The occlusion sites of the unexpected stent detachment were the proximal middle cerebral artery (MCA) in 7 cases and the internal carotid artery in 2 cases. The sizes of the stents that unexpectedly detached were $6{\times}30$ mm in 7 cases, $5{\times}30$ mm in 1 case, and $4{\times}20$ mm in 1 case. Four patients had unexpected detachment at the first retrieval, 1 patient at the second, 3 patients at the third, and 1 patient at the fifth. In all of the cases of unexpected detachment at the first retrieval, the stent deployment site was the proximal MCA. After detachment, a proximal marker of the Solitaire stent was observed in 3 patients. However, no marker was visible in the remaining 6 patients. Conclusion : Unexpected Solitaire stent detachment should be considered in the first instance of stent retrieval for a relatively large-diameter stent, especially in elderly patients with MCA occlusions.
Objective : Young neurosurgeons need to focus on the mortality and morbidity of aneurysmal neck clipping to develop a personal experience with an initial series. Methods : Total 88 aneurysms from 75 patients who underwent neck clipping by the same operator from 2001 to 2004 were reviewed. Patients were divided into three groups : first year [Group I], second year [Group II], and third year [Group III] in each group. Location of aneurysm, age, Fisher grade, Hunter-Hess grade [H-H grade], postoperative Glasgow outcome scale [GOS], and complications related to surgical procedures were evaluated with Chi-square and logistic regression analyses. Results : Fourteen patients had complications related to surgery [18.7%]. The major causes of mortality and morbidity related to surgery were cerebral infarction, hemorrhage and brain swelling due to intraoperative rupture, brain retraction and vasospasm. Among the 4 cases of mortality were 2 patients in Group I, 1 patient in Group II and 1 patient in Group III, and location of aneurysms were 2 internal carotid artery[ICA] and 2 posterior communicating artery[PCoA] aneurysms. There were 4 morbidity and new neurological deficits in Group I, 4 in Group II and 2 in Group III. Although mortality and morbidity during the learning curve had a statistical significance in H-H grade, age [>60 years old], and aneurysm location [especially ICA aneurysm] as variables, mortality mainly occurred in ICA and PCoA aneurysms. Conclusion : Experienced supervision or endovascular approach should be considered for the treatment of ICA and PCoA aneurysms during the learning curve.
Objective: Peritumoral brain edema(PTBE) accounts for approximately 60% of meningiomas. It has not been identified why vasogenic edema, frequently shown in intra-axial tumors is also developed in extra-axial tumor such as meningiomas. Therefore, the authors assess the peritumoral brain edema of meningiomas with a focus on the angiographic pattern and expression of MIB-1 to clarify their correlation. Methods: A total 32 cases of meningioma was studied. The authors attempted to identify 1) the location of PTBE and the edema index (EI), 2) the location and dominancy of pial supply compared with meningeal supply, 3) the biological activity of meningiomas indicated by the MIB-1 LI (labeling index), 4) their interaction. Results: No PTBE was observed in the meningiomas without pial arterial supplement from internal carotid artery (ICA) and vertebral artery (VA). The PTBE of meningiomas with pial supply was developed intensely along the pial arterial supplement, and increased statistically in proportion to the extent of pial supply from ICA or VA rather than meningeal supply. Also, the MIB-1 LI in meningiomas tended to be larger in the tumors of the larger EI and the dominancy of pial supply. Conclusion: A strong correlation is found between the extent of PTBE in meningiomas and the dominancy of pial supply. The MIB-1 LI also tend to be associated with the PTBE. Therefore, the MIB-1 LI in benign meningiomas may represent not only the proliferative potential of the tumor, but also the biological activity like angiogenesis.
Objective : Although removal of the anterior clinoid process (ACP) is essential surgical technique, studies about quantitative measurements of the space broadening by the anterior clinoidectomy are rare. The purposes of this study are to investigate the dimension of the ACP, to quantify the improved exposure of the parasellar space after extradural anterior clinoidectomy and to measure the correlation of each structure around the paraclinoidal area. Methods : Eleven formalin-fixed Korean adult cadaveric heads were used and frontotemporal craniotomies were done bilaterally. The length of C6 segment of the internal carotid artery on its lateral and medial side and optic nerve length were checked before and after anterior clinoidectomy. The basal width and height of the ACP were measured. The relationships among the paraclinoidal structures were assessed. The origin and projection of the ophthalmic artery (OA) were investigated. Results : The mean values of intradural basal width and height of the ACP were 10.82 mm and 7.61 mm respectively. The mean length of the C6 lateral and medial side increased 49%. The mean length of optic nerve increased 97%. At the parasellar area, the lengths from the optic strut to the falciform liament, distal dural ring, origin of OA were 6.69 mm, 9.36 mm and 5.99 mm, respectively. The distance between CN III and IV was 11.06 mm. Conclusion : With the removal of ACP, exposure of the C6 segments and optic nerve can expand 49% and 97%, respectively. This technique should be among a surgeon's essential skills for treating lesions around the parasellar area.
Kim, Young Jin;Kim, Jae Min;Yi, Hyeong Joong;Bak, Koang Hum;Kim, Choong Hyun;Oh, Suck Jun
Journal of Korean Neurosurgical Society
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v.29
no.4
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pp.521-527
/
2000
Objective : In general, most of saccular aneurysms arise at arterial divisions, but those arising at unbranched site are rare. These aneurysms might impose neurosurgeons a formidable surgical challenge, due to uncommon features and a difficult surgical technique. Methods : Between the period of Jan. 1996 and Dec. 1998, a total of 110 cases of aneurysms were operated. Among them, five cases of unbranched site aneurysms were retrospectively analyzed through medical records, angiographic and operative findings. Results : The incidence of aneurysms unrelated to arterial branches was 4.5%. All cases presented with subarachnoid hemorrhage(SAH) ; three(60%) were at internal carotid artery(ICA) and two(40%) at middle cerebral artery (MCA). Two had a history of hypertension and three showed atherosclerotic changes in the arterial wall. One ICA and one MCA aneurysms proved to be a blood blister-like aneurysm(BBA) in their shape. Strikingly, a rapid neurological deterioration was shown in two ruptured ICA variants, which resulted in death and another two aneurysms left with morbidity. Conclusion : The preoperative neurological status in most cases was relatively poor compared to that of aneurysms arising at a branched site. Regarding its pathogenesis, atherosclerosis as well as hemodynamic factors may play an important role in formation of these variant aneurysms among various etiological factors. The overall prognosis of unbranched site aneurysms was worse than that of branched site aneurysms. In cases of BBAs, special attention was requisite to handle them during clipping and/or wrapping due to an easy fragile, thin aneurysmal wall.
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