Does work time limit for resident physician affect short-term treatment outcome and hospital length of stay in patients with spontaneous intracerebral hemorrhage?: a two-year experience at a single training hospital in South Korea

Objective@#To compare short-term treatment outcomes at hospital discharge and hospital length of stay (LOS) in patients with spontaneous intracerebral hemorrhage (sICH) before and after introduction of resident physician work time limit (WTL). @*Methods@#We retrospectively reviewed consecutive patients treated for sICH at our institution between 2016 and 2019. Then we dichotomized these patients into two groups, pre-WTL and post-WTL. We analyzed demographic elements and clinical features, and hospital length of stay (LOS). We evaluated short-term outcome using modified Rankin scale score at hospital discharge and then divided it into “good” and “poor” outcome groups. We subsequently, compared short-term treatment outcome and hospital LOS between the pre-WTL and post-WTL groups. @*Results@#Out of 779 patients, 420 patients (53.9%) were included in the pre-WTL group, and 359 (46.1%) in post-WTL. The mortality rate in sICH patients was higher in the post-WTL group (pre-WTL; 13.6% vs. post-WTL; 17.3%), but there was no statistically significant difference in short-term outcome including mortality (p=0.332) between the groups. The LOS also, was not significantly different between the two groups (pre-WTL; 19.0 days vs. post-WTL; 20.2 days) (p=0.341). The initial Glasgow Coma Scale score, personal stroke history, and mean age were the only independent outcome predicting factors for patients with sICH. @*Conclusions@#Some neurosurgeons may expect poorer outcome for sICH after implementation of the WTL of the K-MHW for resident physician however, enforcement of the WTL did not significantly influence the short-term outcome and hospital LOS for sICH in our hospital. Further well-designed multi-institutional prospective studies on the effects of WTL in sICH patient outcome, are anticipated.

Risk factors of postoperative remote intracerebral hemorrhage after craniotomy for ruptured cerebral aneurysms

Objective@#We aimed to identify the relation between perioperative cerebrospinal fluid (CSF) drain through lumbar drainage (LD) and development of postoperative (POP) remote intracerebral hemorrhage (rICH) in craniotomy to treat ruptured intracranial aneurysms. @*Methods@#We retrospectively reviewed consecutive patients who underwent craniotomy for ruptured cerebral aneurysms at the authors’ institution between 1998 and 2004. We subsequently compared the incidence and characteristics of POP rICH between the patients who had a perioperative LD and those who did not. All statistical analyses were conducted using the software package SPSS 19.0 (SPSS Inc., Chicago, IL, USA). A p value of <0.05 was considered statistically significant. @*Results@#We enrolled 688 patients, of which 80 patients (11.6%) received perioperative LD, and 608 did not. LD and non-LD groups were comparable because although clinical characteristics of the two groups were significantly different considering history of hypertension, timing of surgery, and closed system negative pressure suction drain (SD) placement, none of these three variables was an independent risk factor associated with POP rICH in multivariate analysis. POP rICH incidence was significantly higher in the LD goup (12.5%) than non-LD group (0.8%) (p=0.000) in univariate analysis. LD placement was the only independent risk factor associated with the development of rICH in multivariate logistic regression analysis. @*Conclusions@#POP rICH incidence was significantly higher in patients who were managed with perioperative LD than in those who did not. LD insertion in craniotomy for ruptured intracranial aneurysm, should be closely monitored to address the occurrence of POP rICH.

Does work time limit for resident physician affect short-term treatment outcome and hospital length of stay in patients with spontaneous intracerebral hemorrhage?: a two-year experience at a single training hospital in South Korea

Objective@#To compare short-term treatment outcomes at hospital discharge and hospital length of stay (LOS) in patients with spontaneous intracerebral hemorrhage (sICH) before and after introduction of resident physician work time limit (WTL). @*Methods@#We retrospectively reviewed consecutive patients treated for sICH at our institution between 2016 and 2019. Then we dichotomized these patients into two groups, pre-WTL and post-WTL. We analyzed demographic elements and clinical features, and hospital length of stay (LOS). We evaluated short-term outcome using modified Rankin scale score at hospital discharge and then divided it into “good” and “poor” outcome groups. We subsequently, compared short-term treatment outcome and hospital LOS between the pre-WTL and post-WTL groups. @*Results@#Out of 779 patients, 420 patients (53.9%) were included in the pre-WTL group, and 359 (46.1%) in post-WTL. The mortality rate in sICH patients was higher in the post-WTL group (pre-WTL; 13.6% vs. post-WTL; 17.3%), but there was no statistically significant difference in short-term outcome including mortality (p=0.332) between the groups. The LOS also, was not significantly different between the two groups (pre-WTL; 19.0 days vs. post-WTL; 20.2 days) (p=0.341). The initial Glasgow Coma Scale score, personal stroke history, and mean age were the only independent outcome predicting factors for patients with sICH. @*Conclusions@#Some neurosurgeons may expect poorer outcome for sICH after implementation of the WTL of the K-MHW for resident physician however, enforcement of the WTL did not significantly influence the short-term outcome and hospital LOS for sICH in our hospital. Further well-designed multi-institutional prospective studies on the effects of WTL in sICH patient outcome, are anticipated.

Glucose Hypometabolism in Hippocampal Subdivisions in Alzheimer's Disease: A Pilot Study Using High-Resolution ¹⁸F-FDG PET and 7.0-T MRI

BACKGROUND AND PURPOSE: Atrophy of the hippocampus is an important clinical diagnostic marker of Alzheimer's disease (AD), and so assessments of hippocampal activity and its subdivisions might provide invaluable information. This study compared the glucose metabolism of hippocampal subdivisions in mild-AD patients and healthy controls. METHODS: High-resolution T2*-weighted gradient-echo magnetic resonance imaging (MRI) images and ¹⁸F-fluorodeoxyglucose (FDG) positron-emission tomography (PET) images were acquired using 7.0-T MRI and high-resolution research tomograph FDG-PET, respectively, in 9 early-stage AD patients and 10 healthy subjects. The hippocampal body was divided into three equal parts (anterior, middle, and posterior), and in each part a region of interest (ROI) was drawn over the cornus ammonis (CA)1, CA2/3, CA4/dentate gyrus (DG), and subiculum. The standardized uptake values of the hippocampal subdivisions were calculated for each ROI as ratios relative to the pons standardized uptake value. Statistical analysis was conducted using the Mann-Whitney U test. RESULTS: Patients with early-stage AD patients showed significantly less metabolic activity than healthy controls focally in the middle (p=0.050) and posterior (p=0.034) CA2/3 regions of the right hippocampus, and significantly less activity throughout the left hippocampal body in the anterior CA2/3 (p=0.027) and CA4/DG (p=0.027) regions, the middle CA1 region (p=0.011), and the posterior CA1 (p=0.034), CA2/3 (p=0.007), and CA4/DG (p=0.014) regions. CONCLUSIONS: It was possible to use high-resolution PET-MRI fusion images to identify hippocampus subdivisions and assess glucose metabolism in the subfields. Reductions in metabolic activity were found to vary along the hippocampal axis in early-stage AD patients.

Necessity of Surgical Site Closed Suction Drain for Pterional Craniotomy

OBJECTIVE: The aim of this study was to assess the benefit of using a prophylactic surgical site closed suction drain in pterional craniotomy. MATERIALS AND METHODS: A retrospective review was conducted on 607 consecutive patients who underwent a pterional craniotomy for treatment of intracranial anterior circulation aneurysms over a 5-year period. Between January 2000 and December 2004, 607 patients were divided into two groups, those who had a prophylactic suction drain during closure of the surgical site (drain group, DG) and those who did not (non-drain group, NDG). Head computed tomography (CT) was taken routinely on postoperative day (POD) 1, 7, and 14. Patients' demographics, incidence of surgical site complications, and courses of surgical site healing which were evaluated radiologically by the thickness of the surgical site myocutaneous layer, were analyzed between DG and NDG. RESULTS: Patients' demographics and characteristics did not differ significantly between the two groups. The head CT showed that the degree of changes in the postoperative surgical site thickness was 148% at POD 1, 209% at POD 7, and 198% at POD 14 in DG, and 118% at POD 1, 152% at POD 7, and 158% at POD 14 in NDG compared to the preoperative value. Postoperative surgical site hematoma was 7.9% (22/274) in DG and 2.4% (8/333) in NDG. CONCLUSION: Prophylactic use of an epidural and/or subgaleal closed suction drain does not appear to be necessary for prevention of postoperative surgical site hematoma as well as for promotion of surgical site healing in pterional craniotomy.

Necessity of Surgical Site Closed Suction Drain for Pterional Craniotomy

OBJECTIVE: The aim of this study was to assess the benefit of using a prophylactic surgical site closed suction drain in pterional craniotomy. MATERIALS AND METHODS: A retrospective review was conducted on 607 consecutive patients who underwent a pterional craniotomy for treatment of intracranial anterior circulation aneurysms over a 5-year period. Between January 2000 and December 2004, 607 patients were divided into two groups, those who had a prophylactic suction drain during closure of the surgical site (drain group, DG) and those who did not (non-drain group, NDG). Head computed tomography (CT) was taken routinely on postoperative day (POD) 1, 7, and 14. Patients' demographics, incidence of surgical site complications, and courses of surgical site healing which were evaluated radiologically by the thickness of the surgical site myocutaneous layer, were analyzed between DG and NDG. RESULTS: Patients' demographics and characteristics did not differ significantly between the two groups. The head CT showed that the degree of changes in the postoperative surgical site thickness was 148% at POD 1, 209% at POD 7, and 198% at POD 14 in DG, and 118% at POD 1, 152% at POD 7, and 158% at POD 14 in NDG compared to the preoperative value. Postoperative surgical site hematoma was 7.9% (22/274) in DG and 2.4% (8/333) in NDG. CONCLUSION: Prophylactic use of an epidural and/or subgaleal closed suction drain does not appear to be necessary for prevention of postoperative surgical site hematoma as well as for promotion of surgical site healing in pterional craniotomy.

A Case Report of Preoperative and Postoperative 7.0T Brain MRI in a Patient with a Small Cell Glioblastoma

A 45-yr-old female patient was admitted with one-month history of headache and progressive left hemiparesis. Brain magnetic resonance imaging (MRI) demonstrated a mass lesion in her right frontal lobe. Her brain tumor was confirmed as a small cell glioblastoma. Her follow-up brain MRI, taken at 8 months after her initial surgery demonstrated tumor recurrence in the right frontal lobe. Contrast-enhanced 7.0T brain magnetic resonance imaging (MRI) was safely performed before surgery and at the time of recurrence. Compared with 1.5T and 3.0T brain MRI, 7.0T MRI showed sharpened images of the brain tumor contexture with detailed anatomical information. The fused images of 7.0T and 1.5T brain MRI taken at the time of recurrence demonstrated no significant discrepancy in the positions of the anterior and the posterior commissures. It is suggested that 7.0T MRI can be safely utilized for better images of the maligant gliomas before and after surgery.

Neural Substrates of Hanja (Logogram) and Hangul (Phonogram) Character Readings by Functional Magnetic Resonance Imaging

The two basic scripts of the Korean writing system, Hanja (the logography of the traditional Korean character) and Hangul (the more newer Korean alphabet), have been used together since the 14th century. While Hanja character has its own morphemic base, Hangul being purely phonemic without morphemic base. These two, therefore, have substantially different outcomes as a language as well as different neural responses. Based on these linguistic differences between Hanja and Hangul, we have launched two studies; first was to find differences in cortical activation when it is stimulated by Hanja and Hangul reading to support the much discussed dual-route hypothesis of logographic and phonological routes in the brain by fMRI (Experiment 1). The second objective was to evaluate how Hanja and Hangul affect comprehension, therefore, recognition memory, specifically the effects of semantic transparency and morphemic clarity on memory consolidation and then related cortical activations, using functional magnetic resonance imaging (fMRI) (Experiment 2). The first fMRI experiment indicated relatively large areas of the brain are activated by Hanja reading compared to Hangul reading. The second experiment, the recognition memory study, revealed two findings, that is there is only a small difference in recognition memory for semantic transparency, while for the morphemic clarity was much larger between Hanja and Hangul. That is the morphemic clarity has significantly more effect than semantic transparency on recognition memory when studies by fMRI in correlation with behavioral study.

Association Between the Daily Temperature Range and Occurrence of Spontaneous Intracerebral Hemorrhage

OBJECTIVE: We have observed, anecdotally, that the incidence of primary spontaneous intracerebral hemorrhage (sICH), as well as spontaneous subarachnoid hemorrhage, varies in accordance with seasonality and meteorological conditions. This retrospective single-hospital-based study aimed to determine the seasonality of sICH and the associations, if any, between the occurrence of sICH and meteorological parameters in Incheon city, which is a northwestern area of South Korea. METHODS: Electronic hospital data on 708 consecutive patients admitted with primary sICH from January 2008 to December 2010 was reviewed. Traumatic and various secondary forms of ICHs were excluded. Average monthly admission numbers of sICH were analyzed, in relation with the local temperature, atmospheric pressure, humidity, and daily temperature range data. The relationships between the daily values of each parameter and daily admission numbers of sICH were investigated using a combination of correlation and time-series analyses. RESULTS: No seasonal trend was observed in sICH-related admissions during the study period. Furthermore, no statistically significant correlation was detected between the daily sICH admission numbers and the meteorological parameters of temperature, atmospheric pressure and humidity. The daily temperature range tended to correlate with the number of daily sICH-related admissions (p = 0.097). CONCLUSION: This study represents a comprehensive investigation of the association between various meteorological parameters and occurrence of spontaneous ICH. The results suggest that the daily temperature range may influence the risk of sICH.

Association Between the Daily Temperature Range and Occurrence of Spontaneous Intracerebral Hemorrhage

OBJECTIVE: We have observed, anecdotally, that the incidence of primary spontaneous intracerebral hemorrhage (sICH), as well as spontaneous subarachnoid hemorrhage, varies in accordance with seasonality and meteorological conditions. This retrospective single-hospital-based study aimed to determine the seasonality of sICH and the associations, if any, between the occurrence of sICH and meteorological parameters in Incheon city, which is a northwestern area of South Korea. METHODS: Electronic hospital data on 708 consecutive patients admitted with primary sICH from January 2008 to December 2010 was reviewed. Traumatic and various secondary forms of ICHs were excluded. Average monthly admission numbers of sICH were analyzed, in relation with the local temperature, atmospheric pressure, humidity, and daily temperature range data. The relationships between the daily values of each parameter and daily admission numbers of sICH were investigated using a combination of correlation and time-series analyses. RESULTS: No seasonal trend was observed in sICH-related admissions during the study period. Furthermore, no statistically significant correlation was detected between the daily sICH admission numbers and the meteorological parameters of temperature, atmospheric pressure and humidity. The daily temperature range tended to correlate with the number of daily sICH-related admissions (p = 0.097). CONCLUSION: This study represents a comprehensive investigation of the association between various meteorological parameters and occurrence of spontaneous ICH. The results suggest that the daily temperature range may influence the risk of sICH.

Anterior Commissure - Posterior Commissure Revisited

OBJECTIVE: The anterior commissure (AC) and posterior commissure (PC) are the two distinct anatomic structures in the brain which are difficult to observe in detail with conventional MRI, such as a 1.5T MRI system. However, recent advances in ultra-high resolution MRI have enabled us to examine the AC and PC directly. The objective of the present study is to standardize the shape and size of the AC and PC using a 7.0T MRI and to propose a new brain reference line. MATERIALS AND METHODS: Thirty-four, 21 males and 13 females, healthy volunteers were enrolled in this study. After determining the center of each AC and PC, we defined the connection of these centers as the central intercommissural line (CIL). We compared the known extra- and intra-cerebral reference lines with the CIL to determine the difference in the angles. Additionally, we obtained horizontal line from flat ground line of look front human. RESULTS: The difference in angle of the CIL and the tangential intercommissural line (TIL) from the horizontal line was 8.7 +/- 5.1 (11 +/- 4.8) and 17.4 +/- 5.2 (19.8 +/- 4.8) degrees in males and females, respectively. The difference in angle between the CIL and canthomeatal line was 10.1 in both male and female, and there was no difference between both sexes. Likewise, there was no significant difference in angle between the CIL and TIL between both sexes (8.3 +/- 1.1 in male and 8.8 +/- 0.7 in female). CONCLUSION: In this study, we have used 7.0T MRI to define the AC and PC quantitatively and in a more robust manner. We have showed that the CIL is a reproducible reference line and serves as a standard for the axial images of the human brain.

Early Experience of Pre- and Post-Contrast 7.0T MRI in Brain Tumors

We investigated the safety and clinical applicability of 7.0 Tesla (T) brain magnetic resonance imaging (MRI) in patients with brain tumors. Twenty-four patients with intraaxial or extraaxial brain tumors were enrolled in this study. 7.0T MRIs of T2*-weighted axial and T1-weighted coronal or sagittal images were obtained and compared with 1.5T brain MRIs. The T2*-weighted images from 7.0T brain MRI revealed detailed microvasculature and the internal contents of supratentorial brain tumors better than that of 1.5T brain MRI. For brain tumors located in parasellar areas or areas adjacent to major cerebral vessels, flow-related artifacts were exaggerated in the 7.0T brain MRIs. For brain tumors adjacent to the skull base, susceptibility artifacts in the interfacing areas of the paranasal sinus and skull base hampered the aquisition of detailed images and information on brain tumors in the 7.0T brain MRIs. This study shows that 7.0T brain MRI can provide detailed information on the intratumoral components and margins in supratentorial brain tumors. Further studies are needed to develop refined MRI protocols for better images of brain tumors located in the skull base, parasellar, and adjacent major cerebrovascular structures.

Impact of Admission Month on Outcomes in Spontaneous Subarachnoid Hemorrhage: Evidence Against the March Effect

OBJECTIVE: We attempted to identify the presence of a so called 'March effect (or phenomenon)' (which had long been known as a 'July effect' in western countries), a transient increase in adverse outcomes during an unskilled period for new interns and residents in a teaching hospital, among a cohort of patients with spontaneous subarachnoid hemorrhage (sSAH). METHODS: A total of 455 consecutive patients with sSAH from our department database from 2008 to 2010 were enrolled retrospectively and the admission month, patient demographics and clinical characteristics, treatment modalities and discharge outcomes were analyzed. Multivariate regression analysis was used to determine whether unfavorable discharge and in-hospital mortality showed a significant increase during the unskilled months for new interns and residents (from March to May) in a pattern suggestive of a "March effect". RESULTS: Among 455 patients with sSAH, 113 patients were treated during the unskilled period (from March to May) and the remaining 342 patients were treated during the skilled period (from June until February of the next year). No statistically significant difference in demographics and clinical characteristics was observed between patients treated during these periods. In addition, the mortality and unfavorable discharge rates of the un-skilled period were 16.8% and 29.7% and those of the skilled period were 15.5% and 27.2%, respectively. However, no statistically significant difference was observed between them. CONCLUSIONS: Findings of our study suggest that there was no 'March effect' on the mortality rate and unfavorable discharge rate among patients with sSAH in our hospital during the study period.

The Comparative Study of Microsurgical Cerebral Aneurysm Clip Implants; Titanium Clip vs. Stainless Steel Clip

OBJECTIVE: To perform a comparative study between two groups of populations, titanium (T) group versus stainless steel (S) group, who were clipped with titanium and stainless steel materials, respectively, the incidence of regrowth from the original aneurysms, the clip slippage, and post-clipping seizure attack were analyzed. The patients were followed more than 5 years after microsurgical cerebral aneurysms clipping. METHODS: Data from 1986 through 2008 were extensively reviewed on a consecutive series of 3,770 patients who referred for ruptured/unruptured cerebral aneurysms. Forty-seven patients in the S group and 48 in the T group who met inclusion criteria, were selected for this study. RESULTS: The incidence of regrowth were noted that two out of total 47 patients (4.3%) in the S group, and none in the T group. The clip slippage was not observed in both groups. And there was no statistical difference (p = 0.242) in terms of regrowth between two groups. Seven out of 47 cases (14.9%) developed post-clipping seizure in the S group. On the other hand, two (4.2%) of 48 patients presented the symptom in the T group. Also, there was no significant difference (p = 0.091) between two groups. CONCLUSIONS: The metallic types of clip employed for the microsurgical cerebral aneurysm clipping does not have any significant clinical outcome differences in this study.

Improvement of a 4-Channel Spiral-Loop RF Coil Array for TMJ MR Imaging at 7T

PURPOSE: In an attempt to further improve the radiofrequency (RF) magnetic (B1) field strength in temporomandibular joint (TMJ) imaging, a 4-channel spiral-loop coil array with RF circuitry was designed and compared with a 4-channel single-loop coil array in terms of B1 field, RF transmit (B1+), signal-to-noise ratio (SNR), and applicability to TMJ imaging in 7T MRI. MATERIALS AND METHODS: The single- and 4-channel spiral-loop coil arrays were constructed based on the electromagnetic (EM) simulation for the investigation of B1 field. To evaluate the computer simulation results, the B1 field and B1 + maps were measured in 7T. RESULTS: In the EM simulation result and MRI study at 7T, the 4-channel spiral-loop coil array found a superior B1 performance and a higher B1 + profile inside the human head as well as a slightly better SNR than the 4-channel single-loop coil array. CONCLUSION: Although B1 fields are produced under the influence of the dielectric properties of the subject rather than the coil configuration alone at 7T, each RF coil exhibited not only special but also specific characteristics that could make it suited for specific application such as TMJ imaging.

A Proposal of New Reference System for the Standard Axial, Sagittal, Coronal Planes of Brain Based on the Serially-Sectioned Images

Sectional anatomy of human brain is useful to examine the diseased brain as well as normal brain. However, intracerebral reference points for the axial, sagittal, and coronal planes of brain have not been standardized in anatomical sections or radiological images. We made 2,343 serially-sectioned images of a cadaver head with 0.1 mm intervals, 0.1 mm pixel size, and 48 bit color and obtained axial, sagittal, and coronal images based on the proposed reference system. This reference system consists of one principal reference point and two ancillary reference points. The two ancillary reference points are the anterior commissure and the posterior commissure. And the principal reference point is the midpoint of two ancillary reference points. It resides in the center of whole brain. From the principal reference point, Cartesian coordinate of x, y, z could be made to be the standard axial, sagittal, and coronal planes.

Accuracy of the Free Hand Placement of an External Ventricular Drain (EVD) / 대한뇌혈관외과학회지

OBJECTIVE: Free hand insertion of an external ventricular drain (EVD) is one of the most common emergency neurosurgical procedures, usually performed on critically ill patients. Complications such as infection and hemorrhage that accompany the placement of an EVD have been studied thoroughly, but few reports have focused on the accuracy of EVD positioning. As a result, the authors of this paper retrospectively studied the accuracy of tip positioning in the placement of an EVD. METHODS: One hundred and thirteen emergency EVDs were performed through Kocher's point during the past 3 years. All patients underwent the following procedures: at least one routine post-EVD computed tomographic (CT) scan that was retrospectively reviewed for accuracy of the EVD tip position, calculation of the Evan's index, and measurement of the intracranial length of the EVD. We divided the EVD tip position into 6 groups as follows:1) ipsilateral frontal horn of the lateral ventricle, 2) contralateral frontal horn of the lateral ventricle, 3) third ventricle, 4) body of the ipsilateral or contralateral lateral ventricle, 5) basal cisterns, or 6) brain parenchyma. Among the 6 groups, only the ipsilateral frontal horn group was considered to be the correct position for the EVD tip. RESULTS: The mean age of the patients was 55.6+/-15.3 years (age range, 12~90 years), and the most common indication for the EVD was supratentorial intracerebral hemorrhage (ICH) and intraventricular hemorrhage (IVH) (57.5%). Forty-five out of a total of 113 EVDs were placed by inexperienced neurosurgical trainees, and the remaining 68 were placed by experienced practitioners. Among 113 post-EVD CT scans, 48 EVD tips (42.5%) were in the ipsilateral frontal horn of the lateral ventricle (considered to be the correct position); 22 (19.5%) were in the third ventricle, 16 (14.1%) in the body of the ipsilateral or contralateral lateral ventricle, 14 (12.4%) in the contralateral frontal horn of the lateral ventricle, 11 (9.7%) within the brain parenchyma and 2 (1.8%) in the basal cistern. The mean estimated EVD length was 57+/-8.4mm. The mean length of EVDs that were positioned in the ipsilateral frontal horn was 55+/-4.3 mm, whereas the mean lengths of EVDs in the parenchyma and basal cistern were 64+/-14mm and 72+/-3.5mm, respectively. In addition, there was no statistically significant relationship between the surgeon's experience and the accuracy of the position of the EVD tip (p > 0.05). CONCLUSION: Emergency free hand placement of an EVD might be an inaccurate procedure. Further multi-institutional prospective studies are required to assess the accuracy and complications of free hand insertion of EVDs in an emergency setting. Studies are also needed on the feasibility of routine use of intra-operative neuro-navigation of other guidance tools, such as ultrasonography.

One vs. Two Burr Hole Craniostomy in Surgical Treatment of Chronic Subdural Hematoma

OBJECTIVE: Chronic subdural hematoma (CSDH) is one of the most common types of traumatic intracranial hemorrhage, usually occurring in the older patients, with a good surgical prognosis. Burr hole craniostomy is the most frequently used neurosurgical treatment of CSDH. However, there have been only few studies to assess the role of the number of burr holes in respect to recurrence rates. The aim of this study is to compare the postoperative recurrence rates between one and two burr craniostomy with closed-system drainage for CSDH. METHODS: From January 2002 to December 2006, 180 consecutive patients who were treated with burr hole craniostomy with closed-system drainage for the symptomatic CSDH were enrolled. Pre- and post-operative computed tomography (CT) scans and/or magnetic resonance imaging (MRI) were used for radiological evaluation. The number of burr hole was decided by neurosurgeon's preference and was usually made on the maximum width of hematoma. The patients were followed with clinical symptoms or signs and CT scans. All the drainage catheters were maintained below the head level and removed after CT scans showing satisfactory evacuation. All patients were followed-up for at least 1 month after discharge. RESULTS: Out of 180 patients, 51 patients were treated with one burr hole, whereas 129 were treated with two burr holes. The overall postoperative recurrence rate was 5.6% (n = 10/180) in our study. One of 51 patients (2.0%) operated on with one burr hole recurred, whereas 9 of 129 patients (7.0%) evacuated by two burr holes recurred. Although the number of burr hole in this study is not statistically associated with postoperative recurrence rate (p > 0.05), CSDH treated with two burr holes showed somewhat higher recurrence rates. CONCLUSION: In agreement with previous studies, burr hole craniostomy with closed drainage achieved a good surgical prognosis as a treatment of CSDH in this study. Results of our study indicate that burr hole craniostomy with one burr hole would be sufficient to evacuate CSDH with lower recurrence rate.

Canine model of ischemic stroke with permanent middle cerebral artery occlusion: clinical and histopathological findings

The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.

Cost Analysis for the Management of Cerebral Aneurysms: Comparison between Clipping and Coiling / 대한뇌혈관외과학회지

OBJECTIVE: The aim of this study is to compare the costs for the management of ruptured or unruptured cerebral aneurysms during hospital stay between surgical and endovascular treatment under the Korean national health insurance system. METHODS: It is a retrospective analysis of 301 cases that had been managed for cerebral aneurysms by clipping and/or coiling at Gil Medical Center from January 2003 to December 2004. Of 301 cases, 37 patients were excluded because they were managed by clipping and coiling at the same hospital stay or for the same aneurysm, had cerebral arteriovenous malformations also, and died during acute postoperative period. The authors analyzed the costs for hospital stay, laboratory test, medications, surgeon's fee, anesthetic fee and disposable medical supplies. We analyzed the costs only for the treatment of cerebral aneurysms and eliminated the expenses for other coexisting diseases, rehabilitation, and long-term follow-up. All statistical analyses were performed by using SPSS software version 11.5 (SPSS Institute Inc., Chicago, IL). RESULTS: The total number of clipping group was 208 and of coiling was 56. The total mean cost (in Won, \) per patient with ruptured aneurysm in the clipping group and coiling group were \16,986,009+/-\3,037,006 and \18,685,125+/-\4,519,573, respectively. For the unruptured aneurysm, the total mean cost per patient were \16,871,981+/-\3,434,005 in clipping, and \16,383,267+/-\2,480,184 in coiling. Coiling group resulted in shorter hospital stay and less medication, but there was no statistically significant difference in the total mean cost between clipping and coiling. CONCLUSION: Although coiling group had a shorter hospital stay and less medication costs than clipping group, the total mean cost for coiling was more than clipping without statistical significance because the costs of disposable medical supplies for the coiling were much more expensive than those for the clipping under the current Korean national insurance system.