Outcome of External Ventricular Drainage according to the Operating Place: the Intensive Care Unit versus Operating Room / 대한구급학회지

BACKGROUND: External ventricular drainage (EVD) is an important procedure for draining excessive cerebrospinal fluid (CSF) and monitoring intracranial pressure. Generally, EVD is performed in the operating room (OR) under aseptic conditions. However, in emergency circumstances, the operation may be performed in the intensive care unit (ICU) to save neuro-critical time and to avoid the unnecessary transfer of patients. In this study, we retrospectively analyzed the risk of EVD-induced CNS infections and their outcomes according to the operating place (ICU versus OR). In addition, we compared mortalities as well as hospital and ICU days between the CNS infection and non-CNS infection groups. METHODS: We reviewed medical records, laboratory data and radiographic images of patients who had received EVD operations between January, 2013 and March, 2015. RESULTS: A total of 75 patients (45 men and 30 women, mean age: 58.7 +/- 15.6 years) were enrolled in this study. An average of 1.4 catheters were used for each patient and the mean period of the indwelling catheter was 7.5 +/- 5.0 days. Twenty-six patients were included in the ICU group, and EVD-induced CNS infection had occurred in 3 (11.5%) patients. For the OR group, forty-nine patients were included and EVD-induced CNS infection had occurred in 7 (14.3%) patients. The EVD-induced CNS infection of the ICU group did not increase above that of the OR group. The ICU days and mortality rate were higher in the CNS infection group compared to the non-CNS infection group. The period of the indwelling EVD catheter and the number of inserted EVD catheters were both higher in the CNS infection group. CONCLUSIONS: If the aseptic protocols and barrier precautions are strictly kept, EVD in the ICU does not have a higher risk of CNS infections compared to the OR. In addition, EVD in the ICU can decrease the hospital and ICU days by saving neuro-critical time and avoiding the unnecessary transfer of patients. Therefore, when neurosurgeons decide upon the operating place for EVD, they should consider the benefits of ICU operation and be cautious of EVD-induced CNS infection.

Effectiveness of Osteoporosis Drug in Postmenopausal Women with Spinal Compression Fracture: Combined Consecutive Therapy of Teriparatide and Raloxifene versus Bisphosphonate Single / 대한신경손상학회지

OBJECTIVE: Bisphosphonate, a typical bone resorption inhibitor, is an important first-line drug for treating osteoporosis. Recent studies show a novel paradigm in stimulating bone formation. Teriparatide, which is composed of recombinant human parathyroid hormone, stimulates osteoblasts and induces bone regeneration. Bone mineral density (BMD) that was used before and after the treatment with anti-osteoporosis drug was compared for the effectiveness in therapy between a combination of teriparatide and selective estrogen receptor modulator (SERM), and bisphosphonate. METHODS: We retrospectively reviewed the outcomes of 85 postmenopausal women who were concurrently diagnosed with osteoporosis and spinal compression fracture between November 2008 and January 2015. The targeted group were treated with teriparatide and SERM (TS group, n=26) and bisphosphonate (B group, n=59). RESULTS: In both groups, BMD of femur neck was not improved after the medication. In the TS group, on the other hand the BMD and T-score of lumbar spine has significantly improved. BMD ratio of lumbar spine was prominently higher than those of TS group. CONCLUSION: The combination therapy of teriparatide and SERM was very effective in treating the lumbar spine, compared to that of bisphosphonate. Although the period of teriparatide treatment has been relatively short, the preventive effects of compression fracture were considerable. Thus, combination therapy of teriparatide and SERM is highly recommended for patients who are concerned with spinal compression fracture from osteoporosis.

Outcome of External Ventricular Drainage according to the Operating Place: the Intensive Care Unit versus Operating Room / 대한중환자의학회지

BACKGROUND: External ventricular drainage (EVD) is an important procedure for draining excessive cerebrospinal fluid (CSF) and monitoring intracranial pressure. Generally, EVD is performed in the operating room (OR) under aseptic conditions. However, in emergency circumstances, the operation may be performed in the intensive care unit (ICU) to save neuro-critical time and to avoid the unnecessary transfer of patients. In this study, we retrospectively analyzed the risk of EVD-induced CNS infections and their outcomes according to the operating place (ICU versus OR). In addition, we compared mortalities as well as hospital and ICU days between the CNS infection and non-CNS infection groups. METHODS: We reviewed medical records, laboratory data and radiographic images of patients who had received EVD operations between January, 2013 and March, 2015. RESULTS: A total of 75 patients (45 men and 30 women, mean age: 58.7 +/- 15.6 years) were enrolled in this study. An average of 1.4 catheters were used for each patient and the mean period of the indwelling catheter was 7.5 +/- 5.0 days. Twenty-six patients were included in the ICU group, and EVD-induced CNS infection had occurred in 3 (11.5%) patients. For the OR group, forty-nine patients were included and EVD-induced CNS infection had occurred in 7 (14.3%) patients. The EVD-induced CNS infection of the ICU group did not increase above that of the OR group. The ICU days and mortality rate were higher in the CNS infection group compared to the non-CNS infection group. The period of the indwelling EVD catheter and the number of inserted EVD catheters were both higher in the CNS infection group. CONCLUSIONS: If the aseptic protocols and barrier precautions are strictly kept, EVD in the ICU does not have a higher risk of CNS infections compared to the OR. In addition, EVD in the ICU can decrease the hospital and ICU days by saving neuro-critical time and avoiding the unnecessary transfer of patients. Therefore, when neurosurgeons decide upon the operating place for EVD, they should consider the benefits of ICU operation and be cautious of EVD-induced CNS infection.

Risk Factors of Chronic Subdural Hematoma Progression after Conservative Management of Cases with Initially Acute Subdural Hematoma / 대한신경손상학회지

OBJECTIVE: Acute subdural hematoma (ASDH) patients are treated conservatively or surgically according to the guidelines for surgical treatment. Many patients with thin ASDH and mild neurologic deficit are managed conservatively, but sometimes aggravation of thin ASDH to chronic subdural hematoma (CSDH) results in exacerbated clinical symtoms and consequently requires surgery. The aim of this study is to evaluate risk factors that indicate progression of initially non-operated ASDH to CSDH. METHODS: We divided 177 patients, presenting with ASDH (managed conservatively initially) between January 2008 to December 2013, into two groups; 'CSDH progression group' (n=16) and 'non-CSDH progression group' (n=161). Patient's data including age, sex, past medical history, medication were collected and brain computed tomography was used for radiologic analysis. RESULTS: Our data demonstrated that no significant intergroup difference with respect to age, sex ratio, co-morbid conditions, medication history, ischemic heart disease, liver disease and end-stage renal disease was found. However, Hounsfield unit (hematoma density) and mixed density was higher in the 'ASDH progression group' (67.50+/-7.63) than in the 'non-CSDH progression group' (61.53+/-10.69) (p=0.031). Midline shifting and hematoma depth in the 'CSDH progression group' were significantly greater than the 'non-CSDH progression group' (p=0.067, p=0.005). CONCLUSION: Based on the results of this study, the risk factors that are related to progression of initially non-operated ASDH to CSDH are higher Hounsfield unit and hematoma depth. Therefore, we suggest that ASDH patients, who have bigger hematoma depth and higher Hounsfield unit, should be monitored and managed carefully during the follow-up period.

Clinical Analysis of Risk Factors for Recurrence in Patients with Chronic Subdural Hematoma Undergoing Burr Hole Trephination / 대한신경손상학회지

OBJECTIVE: Chronic subdural hematoma (CSDH) is one of the most common types of intra-cranial hemorrhages usually associated with trauma. Surgical treatment is the treatment of choice and burr hole trephination (BHT) is widely performed. The recurrence rate in the patients with CSDH is 3.7-30%. This study investigated the risk factors associated with the recurrence of patients with CSDH who underwent BHT. METHODS: One hundred twenty-five patients with CSDH underwent BHT. Eight of 125 patients (6.4%) underwent reoperation for recurrent CSDH. We retrospectively analyzed demographic, clinical and radiological findings, catheter tip location and drainage duration as the risk factors for the recurrence of CSDH. RESULTS: Recurrence of CSDH in the high- or mixed-density groups was significantly higher than those in the low- or iso-density groups (p<0.001). Placement of catheter tip at the temporoparietal area was associated with a significantly higher recurrence rate of CSDH than placement at the frontal area (p=0.006) and the brain re-expansion rate (BRR) was much lower than placement at the frontal area (p<0.001). CONCLUSION: The operation may be delayed in high- and mixed-density groups, unless severe symptoms or signs are present. In addition, placing the catheter tip at the frontal area helps to reduce the incidence of postoperative recurrence of CSDH and to increase the BRR.

A Comparative Study of Local versus General Anesthesia for Chronic Subdural Hematoma in Elderly Patients Over 60 Years / 대한신경손상학회지

OBJECTIVE: The purpose of this study is to compare the surgical and anesthetic complications of the local and general anesthesia in chronic subdural hematoma (CSDH) patients. METHODS: We retrospectively analyzed the medical record and brain CT of CSDH patients over 60-years-old, who were treated surgically in our institution between January 2005 and December 2012. RESULTS: One hundred six patients with CSDH were enrolled for this study and 61 patients had a burr hole craniostomy under the local anesthesia. In local anesthesia group, surgical complication was not increased than general anesthesia group. But in general anesthesia group, heart disease such as arrhythmia, acute myocardial infarction was relatively increased than local anesthesia group (p=0.04). And the hospitalization period of local anesthesia group was shorter than that of general anesthesia group (p=0.001). CONCLUSION: In this present study, there was no significant difference of surgical complications between the local and general anesthesia group. But the general anesthesia group had more cardiovascular complications and longer hospitalization periods. In conclusion, when we planned the burr hole craniostomy for the elderly patients with CSDH, local anesthesia should be considered more actively for postoperative prognosis.

Steroid-induced Spinal Epidural Lipomatosis after Suprasella Tumor Resection

Spinal epidural lipomatosis (SEL) is an abnormal localized accumulation of fat tissues in the epidural space. It is strongly related with steroid administration. The symptoms of SEL are various and range from back pain to paraplegia. In severe cases, decompressive laminectomy is the choice of treatment. A 32-year-old woman who had been under long-term steroid administration after suprasellar tumor resection was admitted for both leg radiating pain and weakness. She was diagnosed with SEL and had a decompressive laminectomy. During the operation, we found the nerve roots were compressed by epidural fat tissues and engorged vessels. After the operation, her radiating pain was relieved and motor weakness was improved.

Intravascular Papillary Endothelial Hyperplasia (Masson tumor) of the Skull : Case Report and Literature Review

A 10-year-old female patient presented with a rapidly growing nodular mass lesion on her right frontal area. On skull radiography and computed tomography (CT) imaging, this mass had a well-demarcated punch-out lesion with a transdiploic, exophytic soft tissue mass nodule on the frontal scalp. Magnetic resonance (MR) imaging revealed the presence of a 1.5x1.2x1 cm sized calvarial lesion. This lesion was hypointense on T1 and heterogenous hyperintense on T2 weighted MR images, and exhibited heterogeneous enhancement of the soft tissue filling the punch-out lesion after intravenous administration of gadolinium. En block removal of the tumor with resection of the rim of the normal bone was performed. The pathological diagnosis was intravascular papillary endothelial hyperplasia (IPEH). After surgery, no recurrence was found for 8 months. IPEH is a rare and benign reactive lesion usually found in thrombosed subcutaneous blood vessels. Involvement of skull bone is rare. In this article, we present a case of IPEH involving the calvarium, in a 10-year-old woman.

Effect of Cisternal Drainage on the Shunt Dependency Following Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE: Shunt-dependent chronic hydrocephalus (SDCH) is known to be a major complication associated with aneurysmal subarachnoid hemorrhage (aSAH). Old age is known to be one of numerous factors related to the development of SDCH. This study investigated whether postoperative cisternal drainage affects the incidence of SDCH and clinical outcome in elderly patients with aSAH. METHODS: Fifty-nine patients participated in this study. All patients underwent aneurysmal clipping with cisternal cerebrospinal fluid (CSF) drainage. Clinical variables relevant to the study included age, sex, location of ruptured aneurysm, CT finding and clinical state on admission, clinical outcome, and CSF drainage. We first divided patients into two groups according to age ( or =70 years of age) and compared the two groups. Secondly, we analyzed variables to find factors associated with SDCH in both groups ( or =70 years of age). RESULTS: Of 59 patients, SDCH was observed in 20 patients (33.9 %), who underwent shunt placement for treatment of hydrocephalus. Forty seven percent of cases of acute hydrocephalus developed SDCH. In the elderly group (> or =70 years of age), the duration and amount of CSF drainage did not affect the development of chronic hydrocephalus. CONCLUSION: In elderly patients, although the incidence of SDCH was significantly higher, clinical outcome was acceptable. The duration and the amount of cisternal drainage did not seem to be related to subsequent development of chronic hydrocephalus within elderly patients aged 70 or older.

Inhospital Spontaneous Acute Subdural Hematoma (SADH) Patient with Antiplatelet Therapy due to Acute Cerebral Ischemia: A Case Report / 대한구급학회지

A case of "spontaneous" acute subdural hematoma caused by aspirin and plavix therapy has not been described previously. As an isolated cerebrovascular event related to aspirin and plavix therapy, this is the first report described in the literature. It also represents a new differential diagnosis for nontraumatic acute subdural hematomas.

Comparison of Serum CRP and Procalcitonin in Patients after Spine Surgery

OBJECTIVE: Classical markers of infection cannot differentiate reliably between inflammation and infection after neurosurgery. This study investigated the dynamics of serum procalcitonin (PCT) in patients who had elective spine surgeries without complications. METHODS: Participants were 103 patients (47 women, 56 men) who underwent elective spinal surgery. Clinical variables relevant to the study included age, sex, medical history, body mass index (BMI), site and type of surgery, and surgery duration. Clinical and laboratory data were body temperature, white blood cell count (WBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and PCT, all measured preoperatively and postoperatively on days 1, 3, and 5. RESULTS: PCT concentrations remained at <0.25 ng/mL during the postoperative course except in 2 patients. PCT concentrations did not correlate with age, sex, DM, hypertension, BMI, operation time, operation site, or use of instrumentation. In contrast, CRP concentrations were significantly higher with older age, male, DM, hypertension, longer operation time, cervical operation, and use of instrumentation. CONCLUSION: PCT may be useful in the diagnosing neurosurgical patients with postoperative fever of unknown origin.

Severe Symptomatic Vasospasm following Intraventricular Hemorrhage from Arteriovenous Fistula

The authors present a rare case of severe vasospasm following the rupture of arteriovenous fistula. On initial CT scan, hematoma in the corpus callosum and left inferior frontal region with surrounding cerebromalacia and all ventricles without apparent subarachnoid hemorrhage were seen. Angiograms showed arterivenous fistula but did not show cerebral vasospasm. Thirteen days after admission the neurological state of patient suddenly deteriorated and bilateral motor weaknesses developed. Following angiograms revealed severe narrowing on the supraclinoid portion of bilateral internal carotid arteries, bilateral anterior cerebral arteries and bilateral middle cerebral arteries. Transluminal angioplasty and intra-arterial papaverine infusion were performed. The patient remained stable with moderate neurologic deficits.

Initial Troponin Level as a Predictor of Prognosis in Patients with Intracerebral Hemorrhage

OBJECTIVE: It has been suggested that elevated cardiac troponin T (cTnT) level is a marker of increased risk of mortality in acute ischemic stroke and subarachnoid hemorrhage (SAH). However, the association of serum cTnT level and prognosis of intracerebral hemorrhage (ICH) has been sparsely investigated. The aim of this study was to identify the relationship between cTnT level and the outcome in patients with spontaneous ICH. METHODS: We retrospectively investigated 253 patients identified by a database search from records of patients admitted in our department for ICH between January 1, 2003 and December 31, 2007. The patients were divided into 2 groups; the patients in group 1 (n=225) with serum cTnT values of 0.01 ng/mL or less, and those in group 2 (n=28) with serum cTnT values greater than 0.01 ng/mL. RESULTS: The serum cTnT level was elevated in 28 patients. There were significant differences in sex, hypertension, creatine kinase-myocardial band, midline shift, side of hematoma, and presence of intraventricular hemorrhage between the 2 groups. Logistic regression analysis identified the level of consciousness on admission, cTnT and midline shift as independent predictors of hospital mortality. CONCLUSION: Theses results suggest that increased serum cTnT level at admission is associated with in-hospital mortality and the addition of a serum cTnT assay to routine admission testing should be considered in patients with ICH.

A Comparative Coagulopathic Study for Treatment of Vasospasm by Using Low- and High-molecular Weight Hydroxyethyl Starches

OBJECTIVE: High-molecular-weight hydroxyethyl starch (HES) compromises blood coagulation more than does low-molecular-weight HES. We compared the effects of low- and high-molecular-weight HES for the treatment of vasospasm and investigated the dose relationship with each other. METHODS: Retrospectively, in a series of consecutive 102 patients with subarachnoid hemorrhage (SAH), 35 patients developed clinical symptoms of vasospasm of these fourteen patients were treated with low-molecularweight HES for volume expansion while the other 21 received high-molecular-weight HES as continuous intravenous infusion. Prothrombin time (PT), partial thromboplastin time (PTT), fibrinogen level, and platelet count were all measured prior to initiation, during treatment and after termination of therapy for symptomatic vasospasm. The total dose of HES ranged from 5 L to 14 L and median infusion duration was 10 days. RESULTS: A more pronounced PTT prolongation was observed in high-molecular-weight HES group compared with low-molecular-weight HES group. No other coagulation parameters were altered. Dosage (=duration) shows a positive correlation with PTT. Clinically, significant bleeding episodes were noted in four patients who received high-molecular-weight HES. CONCLUSION: Coagulopathy was developed in direct proportion to molecular weight of starch and dosages. We propose the extreme caution in the administration of HES solution for the vasospasm treatment.

Desmoplastic Fibroma of the Skull

Desmoplastic fibroma is one of the uncommon osseous tumors that present in the skull. Although classified as benign tumor, desmoplastic fibroma exhibits local aggressiveness and has a high potential for recurrence. The most common sites include metaphysis of long bones and mandible. Only 15cases have been described in the skull. We report the 16th case of desmoplastic fibroma of the skull.

Angiographic Characteristics of the Intracranial Saccular Aneurysms to Predict the Rupture / 대한뇌혈관외과학회지

OBJECTIVE: During the last two decades, detection of unruptured intracranial aneurysms has increased because of the improving diagnostic methods, but the management of unruptured intracranial aneurysm is still controversial. We analyzed the angiographic characteristics to compare ruptured aneurysms with unruptured aneurysms. METHODS: The patients were retrospectively selected for this study based on the availability of angiograms and a clear diagnosis of an unruptured or ruptured aneurysm. One hundred sixty nine patients with 209 aneurysms were included in the study. Sixty-one patients harbored only unruptured lesions, 85 only ruptured lesions and 27 had both ruptured and unruptured lesions. RESULTS: The mean age of all the patients was 55.3 years, and it was 53.34 years for those with ruptured aneurysms. It was found that 42.0% of the ruptured aneurysms were on the anterior communicating artery, compared with 10.3% of the unruptured aneurysms. None of the ophthalmic artery aneurysms were ruptured. The mean dome size, depth and aspect ratio of the ruptured aneurysms, except for the neck size, were significantly larger than that of the unruptured aneurysms, but the mean neck size of the ruptured and unruptured aneurysms showed no significant difference. A daughter sac was present in 7.2% of the unruptured aneurysms and in 17.0% of the ruptured aneurysms. CONCLUSION: We suggest that the morphologic features and location of aneurysms should be considered when making decisions regarding whether to treat unruptured aneurysms.

Thirty-day Clinical Outcomes of Carotid Artery Stenting Patients with Symptomatic and Asymptomatic Carotid Artery Stenosis: Clinical Research / 대한뇌혈관외과학회지

OBJECTIVE: Recently, carotid artery stenting (CAS) has become as the first choice of treatment for carotid artery stenosis. Although there are many differences in the outcomes of patients receiving stents among many different study groups, some reports suggest that stenting can be performed with periprocedural complication rates similar to those of a carotid endarterectomy (CEA). In this study, we investigated 39 cases of CAS. METHODS: From May 2003 to March 2007, 39 patients undergoing CAS were reviewed. We analyzed the 30-day morbidity/mortality rate. A minor stroke was defined as a new neurological deficit that either resolved completely within 30 days or increased the NIH Stroke Scale by or =4. RESULTS: Among 39 patients, a minor stroke was noted in three patients (7.7%), and there were no major strokes and deaths. The overall 30-day stroke and death rate was 7.7% (n = 3). CONCLUSION: With the evolution and maturation of equipment and technique, carotid angioplasty and stenting (CAS) is increasingly being used for the treatment of carotid artery disease.

Aspect Ratio(dome/neck) of Ruptured and Unruptured Aneurysms in Relation to Their Sizes and Sites and Ages of Patients: Clinical Research / 대한뇌혈관외과학회지

OBJECT: This study was undertaken to assess the reliability of aspect ratio (AR: the maximum dimension of the dome/width of the neck of an aneurysm) in predicting aneurysm rupture. The authors sought to evaluate the utility of these measures for differentiating ruptured and unruptured aneurysms. METHODS: Patients were retrospectively selected for this study based on the availability of angiograms and a clear diagnosis of an unruptured or ruptured aneurysm. 106 patients with 140 aneurysms were included. 19 patients harbored only unruptured lesions, 70 patients only ruptured lesions, and 17 both ruptured and unruptured lesions. The size of the aneurysms and their ARs were determined by examining the angiographic films. Patient's age and sex, and the location of the aneurysm were also recorded. RESULTS: The ruptured aneurysms were larger and had greater ARs. The mean size of unruptured aneurysms was 4.94 mm and that of ruptured ones was 5.53 mm; the corresponding mean ARs were 1.50 and 1.96, respectively. The odds ratio for rupture rose progressively only for the AR. Only 38.3% of ruptured aneurysms had an AR less than 1.80 compared with 74.0% of unruptured lesions. The odds of rupture were 28-fold greater when the AR was larger than 2.07 compared with an AR with an AR less than or equal to 1.30. Only 9.3% of ruptured aneurysms had and AR less than 1.30 compared with 48.1% of unruptured lesions. CONCLUSION: A high AR might reasonably influence the decision to treat actively an unruptured aneurysm independent of its maximum size, so great care should be taken for patients with unruptured intracranial aneurysms with AR of more than 1.80.

Endovascular Stent Treatment for Traumatic Common Carotid Artery Dissection with Cerebral Infarction : Case Report and Literature Review / 대한뇌혈관외과학회지

Accurate determination of the true incidence of blunt carotid artery injury is difficult because the patient may be asymptomatic or the condition may be masked by concomitant injuries. We present a case of blunt injury to the right common carotid artery and dissection with acute infarction on right fronto-temporo-parietal area and treated with carotid stent. We review the blunt carotid artery injury rate of occurrence, mechanism, presentation, screening, radiologic diagnosis, management and outcome.

The Relationship of CSF Drainage and The Need for Shunting in Patients with Subarachnoid Hemorrhage : A Retrospective Analysis of 81 Patients / 대한뇌혈관외과학회지

OBJECTIVE: Hydrocephalus and vasospasm are the common complications of aneurysmal subarachnoid hemorrhage (SAH). In spite of development of perioperative management and operative technique, hydrocephalus and vasospasm are the causes of the neurological deficit and poor prognosis. This study was designed to investigate whether the frequency of a shunt-dependent hydrocephalus in patient suffering from aneurysmal subarachnoid hemorrhage and delayed cerebral ischemia can be related to the duration and amount of cerebrospinal fluid drainage and medical history. METHODS: Retrospective analysis of consecutive 96 patients with aneurysmal subarachnoid hemorrhage was made from January 2000 to December 2002. Eighty one of these patients underwent the procedure for CSF drainage and 15 patients did not. 81 patients with aneurysmal SAH were divided into two groups which underwent shunt procedure and did not. In these two groups, we investigated and compared the incidence of shunt-dependent hydrocephalus and ischemia according to age, sex, aneurysmal site, H-H grade, Fisher grade, medical history and the amout of CSF drainage. RESULTS: The incidence of hydrocephalus following SAH was 53.1% and shunt-dependent hydrocephalus was 16.7% in 96 patients. The duration, total volume, and daily volume of CSF drainage were 6.9+/-3.3 days, 1542.3+/-982.5 ml, and 211.5+/-49.2 ml, respectively. The relationship between the daily volume of CSF drainage and shunt-dependent hydrocephalus was determined to to be statistically significant (p<0.05). Cerebral infarction and shunt-dependent hydrocephalus were found to be statistically associated (p<0.05). CONCLUSION: The continous drainage of cerebrospinal fluid in patients of aneurysmal subarachnoid hemorrhage increase chance of delayed hydrocephalus and they have not shown decrease cerebral infarction as a result of vasospasm.