Clinical Outcomes of Proton Beam Therapy for Choroidal Melanoma at a Single Institute in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study retrospectively evaluated the clinical outcomes and complications of proton beam therapy (PBT) in a single institution in Korea and quantitatively analyzed the change in tumor volume after PBT using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twenty-four treatment-naïve patients who underwent PBT for choroidal melanoma between 2009 and 2015 were reviewed. Dose fractionation was 60-70 cobalt gray equivalents over 5 fractions. Orbital MRIs were taken at baseline and 3, 6, and 12 months after PBT and annually thereafter. The tumor volume was reconstructed and evaluated by stacking the tumor boundary in each thin-sliced axial T1-weighted image using MIM software. RESULTS: The median follow-up duration was 36.5 months (range, 9 to 82 months). One patient had suspicious local progression and two patients had distant metastasis. The 3-year local progression-free survival, distant metastasis-free survival, and overall survival rates were 95.8%, 95.8%, and 100%,respectively. Five Common Terminology Criteria for Adverse Event ver. 4.03 grade 3-4 toxicities were observed in four patients (16.7%), including one with neovascular glaucoma. The mean tumor volume at the baseline MRI was 0.565±0.084 mL (range, 0.074 to 1.610 mL), and the ratios of the mean volume at 3, 6, and 12 months to that at baseline were 81.8%, 67.3%, and 60.4%, respectively. CONCLUSION: The local controlrate and complication profile after PBT in patientswith choroidal melanoma in Korea were comparable with those reported in a previous PBT series. The change in tumor volume after PBT exhibited a gradual regression pattern on MRI.

Posterior Cerebral Artery Aneurysm: Surgical Result of 11 Patients

OBJECTIVE: Eleven patients treated with posterior cerebral artery(PCA) aneurysm during 6.3-years period are retrospectively reviewed to determine treatment outcome. METHODS: Eleven patients with PCA aneurysm were treated from January 1998 to May 2004. Their medical records and radiologic studies were reviewed retrospectively. The records of these patients were analysed with particular reference to their demographic details, mode of presentation, and treatment outcome. RESULTS: Of the 11 patients, 8 patients presented with symptoms related aneurysmal bleeding. Three patients had unruptured PCA aneurysms. Open or endovascular surgery was performed in 9 patients; None of these patients exhibited a third nerve palsy, visual field deficit, or hemiparesis at the time of presentation. Postoperatively, 2 made a good recovery, 2 had a moderate disability because of cerebral infarction after surgery, and 5 had a severe disability because of cerebral infarction after surgery. Of 2 conservatively treated patients, 1 was doing well but the other died as a result of brain swelling. CONCLUSION: The treatment of the PCA aneurysms is difficult regardless of the aneurysmal size, site, and treatment modality. All reasonable treatment to reduce the risk of associated morbidity should be considered.

T Clinical Experience of Arteriovenous Malformation with Extranidal Aneurysms / 대한뇌혈관외과학회지

OBJECTIVE: The presence of intracranial arteriovenous malformation (AVM) with extranidal aneurysms has been well documented. Attention has been focused on the most appropriate treatment of patients harboring these lesions. The authors analyzed the clinical features, characteristics, and treatment modalities of these lesions based on clinical experiences. METHODS: Between 1996 and 2003, 21 consecutive patients were diagnosed and treated for AVMs associated with extranidal aneurysms (1 patient with intra and extranidal aneurysm). The medical records and neuroimaging studies of the patients were reviewed retrospectively. RESULTS: There were 18 patients with flow-related extranidal aneurysms, 3 patients with flow-unrelated ones. Fifteen (71.4%) of 21 patients presented with intracranial hemorrhage (subarachnoid hemorrhage 10, intracerebral hemorrhge or intraventricular hemorrhage 5) as initial symptom upon admission. Six (28.6%) of 21 patients were admitted with other symptom rather than hemorrhage (3 seizure, 1 headache, 1 TIA, 1 incidental). Fifteen (71.4%) of 21 cases was located predominantly in posterior circulation. We observed that 7 (33.3%) patients experienced subsequent hemorrhage during management. We tried to secure aneurysm initially regardless of presented sypmtoms in most of them. Treatment modalities included surgery, gamma knife radiosurgery, embolization, or combination. Most of cases were treated with combination therapy except 3 patients. CONCLUSIONS: There was a great propensity to hemorrhage, especially extranidal aneurysmal ruture, in patients with AVM associated with extranidal aneurysms. Symptomatic treatment should be considered initially. Owing to increased possible risk of hemorrhage, patients harboring these lesions should be cared aggressively to prevent bleeding.

T Clinical Experience of Arteriovenous Malformation with Extranidal Aneurysms / 대한뇌혈관외과학회지

OBJECTIVE: The presence of intracranial arteriovenous malformation (AVM) with extranidal aneurysms has been well documented. Attention has been focused on the most appropriate treatment of patients harboring these lesions. The authors analyzed the clinical features, characteristics, and treatment modalities of these lesions based on clinical experiences. METHODS: Between 1996 and 2003, 21 consecutive patients were diagnosed and treated for AVMs associated with extranidal aneurysms (1 patient with intra and extranidal aneurysm). The medical records and neuroimaging studies of the patients were reviewed retrospectively. RESULTS: There were 18 patients with flow-related extranidal aneurysms, 3 patients with flow-unrelated ones. Fifteen (71.4%) of 21 patients presented with intracranial hemorrhage (subarachnoid hemorrhage 10, intracerebral hemorrhge or intraventricular hemorrhage 5) as initial symptom upon admission. Six (28.6%) of 21 patients were admitted with other symptom rather than hemorrhage (3 seizure, 1 headache, 1 TIA, 1 incidental). Fifteen (71.4%) of 21 cases was located predominantly in posterior circulation. We observed that 7 (33.3%) patients experienced subsequent hemorrhage during management. We tried to secure aneurysm initially regardless of presented sypmtoms in most of them. Treatment modalities included surgery, gamma knife radiosurgery, embolization, or combination. Most of cases were treated with combination therapy except 3 patients. CONCLUSIONS: There was a great propensity to hemorrhage, especially extranidal aneurysmal ruture, in patients with AVM associated with extranidal aneurysms. Symptomatic treatment should be considered initially. Owing to increased possible risk of hemorrhage, patients harboring these lesions should be cared aggressively to prevent bleeding.

Optimum Radiotherapy Schedule for Uterine Cervical Cancer based-on the Detailed Information of Dose Fractionation and Radiotherapy Technique / 대한방사선종양학회지

BACKGROUND: The best dose-fractionation regimen of the definitive radiotherapy for cervix cancer remains to be clearly determined. It seems to be partially attributed to the complexity of the affecting factors and the lack of detailed information on external and intra-cavitary fractionation. To find optimal practice guidelines, our experiences of the combination of external beam radiotherapy (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT) were reviewed with detailed information of the various treatment parameters obtained from a large cohort of women treated homogeneously at a single institute. MATERIALS AND METHODS: The subjects were 743 cervical cancer patients (Stage IB 198, IIA 77, IIB 364, IIIA 7, IIIB 89 and IVA 8) treated by radiotherapy alone, between 1990 and 1996. A total external beam radiotherapy (EBRT) dose of 23.4~59.4 Gy (Median 45.0) was delivered to the whole pelvis. High-dose-rate intracavitary brachytherapy (HDR-ICBT) was also performed using various fractionation schemes. A Midline block (MLB) was initiated after the delivery of 14.4~43.2 Gy (Median 36.0) of EBRT in 495 patients, while in the other 248 patients EBRT could not be used due to slow tumor regression or the huge initial bulk of tumor. The point A, actual bladder & rectal doses were individually assessed in all patients. The biologically effective dose (BED) to the tumor (alpha/beta=10) and late-responding tissues (alpha/beta=3) for both EBRT and HDR-ICBT were calculated. The total BED values to point A, the actual bladder and rectal reference points were the summation of the EBRT and HDR-ICBT. In addition to all the details on dose-fractionation, the other factors (i.e. the overall treatment time, physicians preference) that can affect the schedule of the definitive radiotherapy were also thoroughly analyzed. The association between MD-BED Gy3 and the risk of complication was assessed using serial multiple logistic regression models. The associations between R-BED Gy3 and rectal complications and between V-BED Gy3 and bladder complications were assessed using multiple logistic regression models after adjustment for age, stage, tumor size and treatment duration. Serial Coxs proportional hazard regression models were used to estimate the relative risks of recurrence due to MD-BED Gy10, and the treatment duration. RESULTS: The overall complication rate for RTOG Grades 1~4 toxicities was 33.1%. The 5-year actuarial pelvic control rate for all 743 patients was 83%. The midline cumulative BED dose, which is the sum of external midline BED and HDR-ICBT point A BED, ranged from 62.0 to 121.9 Gy10 (median 93.0) for tumors and from 93.6 to 187.3 Gy3 (median 137.6) for late responding tissues. The median cumulative values of actual rectal (R-BED Gy3) and bladder point BED (V-BED Gy3) were 118.7 Gy3 (range 48.8~265.2) and 126.1 Gy3 (range: 54.9~267.5), respectively. MD-BED Gy3 showed a good correlation with rectal (p=0.003), but not with bladder complications (p=0.095). R-BED Gy3 had a very strong association (p=<0.0001), and was more predictive of rectal complications than A-BED Gy3. B-BED Gy3 also showed significance in the prediction of bladder complications in a trend test (p=0.0298). No statistically significant dose-response relationship for pelvic control was observed. The Sandwich and Continuous techniques, which differ according to when the ICR was inserted during the EBRT and due to the physicians preference, showed no differences in the local control and complication rates; there were also no differences in the 3 vs. 5 Gy fraction size of HDR-ICBT. CONCLUSION: The main reasons optimal dose-fractionation guidelines are not easily established is due to the absence of a dose-response relationship for tumor control as a result of the high-dose gradient of HDR-ICBT, individual differences in tumor responses to radiation therapy and the complexity of affecting factors. Therefore, in our opinion, there is a necessity for individualized tailored therapy, along with general guidelines, in the definitive radiation treatment for cervix cancer. This study also demonstrated the strong predictive value of actual rectal and bladder reference dosing therefore, vaginal gauze packing might be very important. To maintain the BED dose to less than the threshold resulting in complication, early midline shielding, the HDR-ICBT total dose and fractional dose reduction should be considered.

Optimum Radiotherapy Schedule for Uterine Cervical Cancer based-on the Detailed Information of Dose Fractionation and Radiotherapy Technique / 대한방사선종양학회지

BACKGROUND: The best dose-fractionation regimen of the definitive radiotherapy for cervix cancer remains to be clearly determined. It seems to be partially attributed to the complexity of the affecting factors and the lack of detailed information on external and intra-cavitary fractionation. To find optimal practice guidelines, our experiences of the combination of external beam radiotherapy (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT) were reviewed with detailed information of the various treatment parameters obtained from a large cohort of women treated homogeneously at a single institute. MATERIALS AND METHODS: The subjects were 743 cervical cancer patients (Stage IB 198, IIA 77, IIB 364, IIIA 7, IIIB 89 and IVA 8) treated by radiotherapy alone, between 1990 and 1996. A total external beam radiotherapy (EBRT) dose of 23.4~59.4 Gy (Median 45.0) was delivered to the whole pelvis. High-dose-rate intracavitary brachytherapy (HDR-ICBT) was also performed using various fractionation schemes. A Midline block (MLB) was initiated after the delivery of 14.4~43.2 Gy (Median 36.0) of EBRT in 495 patients, while in the other 248 patients EBRT could not be used due to slow tumor regression or the huge initial bulk of tumor. The point A, actual bladder & rectal doses were individually assessed in all patients. The biologically effective dose (BED) to the tumor (alpha/beta=10) and late-responding tissues (alpha/beta=3) for both EBRT and HDR-ICBT were calculated. The total BED values to point A, the actual bladder and rectal reference points were the summation of the EBRT and HDR-ICBT. In addition to all the details on dose-fractionation, the other factors (i.e. the overall treatment time, physicians preference) that can affect the schedule of the definitive radiotherapy were also thoroughly analyzed. The association between MD-BED Gy3 and the risk of complication was assessed using serial multiple logistic regression models. The associations between R-BED Gy3 and rectal complications and between V-BED Gy3 and bladder complications were assessed using multiple logistic regression models after adjustment for age, stage, tumor size and treatment duration. Serial Coxs proportional hazard regression models were used to estimate the relative risks of recurrence due to MD-BED Gy10, and the treatment duration. RESULTS: The overall complication rate for RTOG Grades 1~4 toxicities was 33.1%. The 5-year actuarial pelvic control rate for all 743 patients was 83%. The midline cumulative BED dose, which is the sum of external midline BED and HDR-ICBT point A BED, ranged from 62.0 to 121.9 Gy10 (median 93.0) for tumors and from 93.6 to 187.3 Gy3 (median 137.6) for late responding tissues. The median cumulative values of actual rectal (R-BED Gy3) and bladder point BED (V-BED Gy3) were 118.7 Gy3 (range 48.8~265.2) and 126.1 Gy3 (range: 54.9~267.5), respectively. MD-BED Gy3 showed a good correlation with rectal (p=0.003), but not with bladder complications (p=0.095). R-BED Gy3 had a very strong association (p=<0.0001), and was more predictive of rectal complications than A-BED Gy3. B-BED Gy3 also showed significance in the prediction of bladder complications in a trend test (p=0.0298). No statistically significant dose-response relationship for pelvic control was observed. The Sandwich and Continuous techniques, which differ according to when the ICR was inserted during the EBRT and due to the physicians preference, showed no differences in the local control and complication rates; there were also no differences in the 3 vs. 5 Gy fraction size of HDR-ICBT. CONCLUSION: The main reasons optimal dose-fractionation guidelines are not easily established is due to the absence of a dose-response relationship for tumor control as a result of the high-dose gradient of HDR-ICBT, individual differences in tumor responses to radiation therapy and the complexity of affecting factors. Therefore, in our opinion, there is a necessity for individualized tailored therapy, along with general guidelines, in the definitive radiation treatment for cervix cancer. This study also demonstrated the strong predictive value of actual rectal and bladder reference dosing therefore, vaginal gauze packing might be very important. To maintain the BED dose to less than the threshold resulting in complication, early midline shielding, the HDR-ICBT total dose and fractional dose reduction should be considered.

The Correlation of Grade Point Average of Medical School and the Score of Korean Medical Licensing Examination / 한국의학교육

PURPOSE: This study analyzed the correlation between grade point average (GPA) of medical school and the score of Korean Medical Licensing Examination (KMLE). METHODS: This study based on the results of 67th KMLE applicants who graduated from a college of medicine in 2003. We also gathered data of these applicants from the college of medicine: gender, age, type of entrance, GPA of basic medicine, clinical medicine, clinical clerkships and final test scores. We analyzed whether there was discrimination between achievement of KMLE passed and that of KMLE failed, which of variables affected the results of KMLE. RESULTS: 173 applicants passed KMLE among 189. There were significant correlations between basic medicine, clinical medicine, final test score and the score of KMLE (respective p-value; < 0.0001). There were also significant differences of GPA between KMLE passed applicants and failed. Final test scores were the most correlated with those of KMLE. If the GPA of 2nd grade was below 2.5 and the GPA of 3rd year grade was below 2.3, they was a high-risk group for failing KMLE (sensitivity 100%, specificity 90%). CONCLUSION: There were significant correlations between the GPA of medical school and the score of KMLE, and significant differences between KMLE passed applicants and failed. A high-risk group of failing KMLE was the students that the GPA of 2nd grade was below 2.5 and the GPA of 3rd grade was below 2.3.

Endovascular Treatment of Bilateral Spontaneous Carotid-cavernous Fistulas

The authors report a case of a 46-year-old woman with bilateral spontaneous carotid-cavernous fistulas(CCFs). The patient was treated by endovascular management via multiple trans-arterial and trans-venous routes. Left side CCF was embolized completely via surgically exposed superior ophthalmic vein route. Right side lesion was tried by multi-modality endovascular trajectories and achieved partial thrombosis by trans-arterial approach. The follow-up angiogram two months after the last embolization showed a complete bilateral elimination of fistulas. Embolization of bilateral complex CCFs can be achieved by multiple trans-arterial and trans-venous routes, including direct surgical exposure of superior ophthalmic vein.

A Case of the Simultaneous Occurrence of Spontaneous Regression and De Novo Formation of the Intracranial Aneurysms

We present a case of the simultaneous occurrence of spontaneous regression and de novo formation of intracranial aneurysm. A 50-year-old man was readmitted for headache and dizziness in April 2002, twelve years after the successful management of the subarachnoid hemorrhage(SAH) by clipping the ruptured left middle cerebral artery(MCA) aneurysm in September 1990. Angiograms obtained at that time also demonstrated the aneurysm on the right A1 segment, which was not treated. The follow-up cerebral angiograms demonstrated that the previously clipped aneurysm was not filled in, suggesting the successful treatment of the previous aneurysm. The left MCA stenosis was also detected. Notably, a new aneurysm developed at the right anterior communicating artery(ACoA) while the aneurysm at the right A1 segment which was not treated previously was markedly decreased in size.

Embolization Therapy for a Ruptured Spinal Artery Aneurysm Associated with Spinal Cord Arteriovenous Malformation and Presenting with Spontaneous Subarachnoid Hemorrhage

Spinal arteriovenous malformations(AVMs) and aneurysms should be suspected when patient present with subarachnoid hemorrhage and intracranial source has not been identified with neurologic findings attributable to the spinal cord. We report a case of subarachnoid hemorrhage(SAH) with ruptured spinal artery aneurysm associated with spinal cord AVM in 37-year old man who presented with sudden loss of consciousness with paraplegia. The result of CT-head arteriography of the brain was SAH with intraventricular hemorrhage but no intracranial aneurysm was identified. Spinal angiography revealed a cervical spinal cord AVM supplied by anterior spinal artery with an aneurysm in the feeder. The treatment of the spinal cord AVM was performed with liquid coil embolic agent, polyvinylacetylate(PVAc) and feeding artery aneurysm was treated with Guglielmi detachable coils(GDCs).

Spontaneous Intracranial Aneurysm in Young Adult Patients: Retrospective Review of 157 Patients

OBJECTIVE: This study is undertaken to review clinical characteristics of spontaneous intracranial aneurysms in young adult patients. METHODS: The authors reviewed medical records and radiological findings in patients, aged 16 to 35 with spontaneous intracranial aneurysm(s) who underwent transcranial or endovascular treatment in our hospital from 1989 to 2002. RESULTS: The number of cases was 157 and the ratio of male to female was 95:62. The majority(88.5%) of patients presented with subarachnoid hemorrhage and underlying medical diseases were found only in 12.1%. Acccording to Hunt-Hess grade, 145 patients(92.4%) showed good clinical grade on admission. Aneurysms were located most commomly at the anterior communicating artery(35.7%). Patients with multiple aneurysms were 11.5% and giant aneurysms were found in 4.5%. We performed transcranial surgery in 95.5% and endovascular treatment in 4.5%. 144 patients(91.7%) showed good outcome at discharge and 8 patients died of rebleeding in two cases, brain swelling in two cases, postoperative infarction after parent artery occlusion in two cases, vasospasm in one case, and acute myocardial infarction in one case. CONCLUSION: Because of good neurological status on admission, low incidence of intraventricular hemorrhage and hydrocephaus, low incidence of underlying medical disease, and low incidence of symptomatic vasospasm, the overall outcomes of the young adult patients are better than those of the old patients.

Long-term Follow-up Results of Gamma Knife Radiosurgery for Benign Tumors Involving Cavernous Sinus

OBJECTIVE: We describe our long-term experiences of gamma knife radiosurgical treatment on benign tumors involving cavernous sinus, including meningiomas, trigeminal neurinomas and pituitary adenomas. METHODS: From June 1990 to January 2001, forty-two patients with benign cavernous sinus tumors were treated with gamma knife radiosurgery in our institution. Of these, twenty-seven patients(64%) had precedently undergone open surgery and others(36%) were treated only with gamma knife. Tumor type distribution was meningiomas(n=20, 48%), trigeminal neurinomas(n=8, 19%) and pituitary adenomas(n=14, 33%). Mean follow-up period was 42.4 months. Mean tumor volume and mean marginal dose were 6.8cm3(Lange 0.37-39.3cm3 and 17.6Gy(range 11-35Gy) respectively. RESULTS: Tumor control was achieved in thirty-nine patients(93%). Tumor enlarged in two patients(1 meningioma and 1 pituitary adenoma). One patient with neurofibromatosis(type 2) accompanied with trigeminal neurinoma expired due to disease progression. Hormonal relapse was occurred three years after radiosurgery for pituitary adenoma in one patient. There were functional improvement in seven patients, including relief in facial pain(2 patients) and improvements of trigeminal nerve or abducens nerve deficits(5 patients). Three tumors have shown cystic change which have been of indolent course. Complications after radiosurgical treatment were oculomotor and abducens nerve palsies in one patient. CONCLUSION: For benign tumors involving cavernous sinus, gamma knife radiosurgery with its excellent long-term tumor control rates and minimal morbidity could serve as a first treatment modality or combination with open surgery in selected patients.

Endovasular Treatment of Cerebral Aneurysm Remnants after Clipping / 대한뇌혈관외과학회지

The authors report experience using GDC (Guglielmi detachable coil) for the treatment of the cerebral aneurysmal remnant following incomplete surgical clipping. All four patients in whom surgical clipping didn't result in complete obliteration of the aneurysmal sac were anterior circulation aneurysmal remnants. In three patients, aneurysmal remnants were diagnosed by routine follow-up angiography, and one case by recurrent subarachnoid hemorrhage. In all patients, remnants of the aneurysm were completely obliterated by embolization using GDC. There was no neurological morbidity and mortality associated with the treatment. Endovascular treatment of the cerebral aneurysmal remnants may be a effective and safe option for patients in whom surgical clipping does not result in complete obliteration of the aneurysmal sac.

Analysis of Mortality Cases of Transcranial Aneurysm Surgery / 대한뇌혈관외과학회지

OBJECTIVES: The authors analyze the causes of mortality cases after transcranial aneurysm surgery for comparing the safety of the treating methods and for the improvement of treatment outcomes of transcranial surgery. METHODS: Patients recordings and radiological studies were retrospectively reviewed. Causes of postoperative mortality were divided into death related to vasospasm, procedure-related, medical complications and preoperative poor neurological conditions. RESULTS: Postoperative mortality cases were 61 (5.78%) of 1054 transcranial aneurysm surgery during a period of from Jul. 1996 to Nov. 2001. Delayed ischemia related to cerebral vasospasm was a leading cause of death following transcranial aneurysm surgery and accounts for 2% (n=21) of all transcranial surgery and 34.4% of all mortality cases. Procedure-related death were 1.23% (n=13) and were related to inadvertent major artery occlusion, vital perforator injury or intraoperative aneurysm rupture. Death related to medical complications (n=8, 0.75%) were mainly from pneumonia (n=6) in the old age (>65) patients. Patients of initial poor neurological grade (Hunt-Hess grade IV-V, n=19) were mainly from large intracranial hematoma (>30 cc) in temporal lobe or sylvian fissure or multiple aneurysmal bleeding before admission. CONCLUSION: The procedure-related mortality of the transcranial aneurysm surgery is about 1% in this large transcranial aneurysm surgery series and transcranial surgery can be a safe mean of treating intracranial aneurysms compared with other tratment modalities.

A Case of Recurrent Expansile Cyst Formation after Gamma Knife Radiosurgery for a Cerebral Arteriovenous Malformation: Role of the Residual Nidus: Case Report

The authors report a case of recurrent expansile cyst formation after gamma knife radiosurgery(GKRS) for a cerebral arteriovenous malformation where the residual nidus might play an important role. A 28-year-old male patient underwent gamma knife radiosurgery for a left parietal lobe arteriovenous malformation which had manifested with generalized tonic-clonic seizure in November 1992. In March 1999, 76 months after GKRS, the patient presented with headache, dysphasia and right hemiparesis and the computed tomography(CT) and magnetic resonance(MR) image revealed a huge cystic lesion with enhancing nodule at the anterior wall of the cyst. Cerebral angiography showed a small residual nidus. Aspiration and drainage of the cystic fluid via a burr hole was performed and the symptoms improved. One year later, in March 2000, the symptoms recurred, and CT and MR image revealed a new huge cystic lesion anterior to the enhancing nodule. Surgical removal of the residual nidus was performed, and there is no recurrence of the cyst for two years till now.

GDC Embolization of Basilar Bifurcation Aneuryms; Consideration of Posterior Cerebral Artery Occlusion

OBJECTIVE: To access the risk factors of posterior cerebral artery(PCA) occlusion during endovascular treat-ment of basilar bifurcation aneurysm and importance of collateral circulation through posterior communicating artery(PCoA) after PCA occlusion, the authors review the results of 25 patients with basilar bifurcation aneurysms treated with Guglielmi detachable coils(GDCs). METHODS: Male to female ratio was 1: 3.2(6: 19) and the mean age of this group was 54. Nineteen patients were presented with subarachnoid hemorrhage, 1 patient had neurologic deficits of hemiplegia and dysarthria, and 5 patients had incidental aneurysms with headache and dizziness. All patients underwent GDC embolization and their clinical results were analyzed. RESULTS: Seven of nine patients who resulted in PCA occlusion had a collateral flow from the anterior circulation through PCoA. Six patients had a PCoA larger than 1mm and they had no symptoms of ischemia after PCA occlusion. One patient who had a PCoA with 0.53mm in diameter had transient ischemic symptoms. The PCA arouse from the aneurysm neck in seven patients, and six of them resulted in PCA occlusion. Four of five patients who had aneurysms with broad neck(<4mm) resulted in PCA occlusion. CONCLUSION: The aneurysm with either broad neck or PCA arising from the aneurysm neck have a high risk of PCA occlusion. After PCA occlusion, significant blood flow from anterior circulation through the PCoA larger than 1mm in diameter can minimize the ischemic result in PCA territories.

Complications Related to Intravascular Treatment of Cerebral Arteriovenous Malformations / 대한뇌혈관학회지

Endovascular embolization as sole therapy is curative only in a small percentage of cases, but is recommended as part of a multimodal approach to reduce the size of a large AVM, and decrease bleeding risk of lesions with multiple or inaccessible feeding vessels or associated aneurysms prior to surgery or radiotherapy. The result of endovascular treatment of a brain AVM in terms of the degree of obliteration achieved and complication rate depends mainly on the endovascular strategy developed and the technique applied. These depend on the specific angioarchitecture and topography of the individual AVM, on the past history and clinical presentation of the patient and on the predefined goal of embolization. The strategy should include the definition of embolization targets, the selection of the most appropriate approach for endovascular navigation, the determination of the sequence of catheterization of individual feeding arteries, the selection of the type of catheters and microcatheters, the selection of the appropriate embolic materials as well as the site and mode of their delivery.

Internal Carotid Artery Trunk Aneurysms: Its Surgical Management and Complication Avoidance

OBJECTIVE: Aneurysms arising from the trunk of the supraclinoid internal carotid artery(ICA) unrelated to the branching are rare and treatment of these aneurysm is well known as difficult due to intraoperative premature rupture and postoperative bleeding. The authors report an analysis of 12 cases of ICA trunk aneurysms treated with transcranial or endovascular methods. METHODS: Between Mar. 1999 and Apr., 2001, 12 patients were treate for the ICA trunk aneurysms. The medical records and neuroimaging studies of the patients were reviewed retrospectively. RESULTS: These 11(92%) presented with symptoms related to intracranial hemorrhage. All aneurysms were small in size. Eleven patients(92%) were in good neurological status(Hunt Hess grade 0-III), one (8%) in poor grade(H-H grade IV). Eight patients were treated with transcranial surgery, operated on by the ipsilateral pterional approach and 4 patients were treated with endovascular surgery. Intraoperative premature rupture of the aneurysm occured in 6 cases(75%) with transcranial surgery and these were managed with ICA trapping in 4 cases, wrapping using temporalis fascia and clip in 1 and clipping with Sundt-Kee encircling clip in 1. The management outcome of the transcranial surgery was: 3(38%) Glasgow outcome scale(GOS) I, 1(12.5%) GOS II, 2(25%) GOS IV, and 2(25%) GOS V(death). The major causes of morbidity and mortality related to transcranial surgery were cerebral infarction and brain swelling due to intraoperative rupture and vasospasm. Four cases underwent endovascular surgery using Guglielmi detachable coils. The management outcome of the endovascular surgery was: 3(75%) GOS I and one GOS V 1(25%). The cause of mortality related to endosaccular coiling was brain swelling due to vasospasm. CONCLUSION: Treatment of the ICA trunk aneurysm, especially with blister-like nature, has high risk of the intraoperative rupture. Prevention and successful management of the intraoperative bleeding can be made by careful preoperative diagnosis of the aneurysm and preparation for the intraoperative rupture.

Spontaneous Intracranial Arteriovenous Fistulas of Posterior Circulation: Experience of 3 Cases / 대한뇌혈관학회지

OBJECTIVES: True spontaneous intracranial arteriovenous fistulas (AVFs) of posterior circulation are very rare. Clinical entity and natural history of these lesions are not well known. We describe our experience in treating these lesions by microsurgical and/or endovascular techniques. CLINICAL PRESENTATION: Two patients were presented with subarachnoid hemorrhage and one with progressive hearing deficit and tinnitus. Angiograms revealed the presence of intracranial AVFs in all three cases and feeding vessels from the basilar perforator, vertebral artery, and anterior inferior cerebellar artery (AICA), respectively. Venous ectatic changes were also combined in all cases. Surgery was performed via a transpetrosal approach in a case of an unruptured AVF, which was fed by a basilar perforator with venous aneurysmal dilatation in pons. However, afferent vessel to the fistula could not be identified in microsurgical field. Endovascular occlusion was performed successfully 2 months later. In a case of spontaneous vertebral AVF presented with subarachnoid hemorrhage, the fistula was occluded and entangled dilated veins were completely excised via a far lateral suboccipital approach. The last case of AICA origin also presented with subarachnoid hemorrhage died from rebleeding during the preparation of endovascular treatment on the same day of the first ictus. CONCLUSION: Spontaneous intracranial AVFs of posterior circulation showed aggressive behavior. We recommand surgical and/or endovascular treatment for these lesions.

Vertebral Artery Injury during Anterior Cervical Spine Surgery: Report of Two Cases

Vertebral artery injury is a rare complication of anterior cervical approach. We report two patients who suffered injury to vertebral artery during anterior cervical spine surgery. The mechanism of injury, their operative management, and the subsequent outcome were assessed and relevant literatures reviewed. The awareness of the possibility of vertebral artery injury is most important to prevent and it's occurrence is best avoided by a thorough understanding of the anatomical relationships of the artery, the spinal canal, and the vertebral body and careful use of surgical instruments.