ABSTRACT
OBJECTIVE: Surgical clipping of the cerebral aenurysm is considered as a standard therapy with endovascular coil embolization. The surgical clipping is known to be superior to the endovascular coil embolization in terms of recurrent rate. However, a recurrent aneurysm which is initially treated by surgical clipping is difficult to handle. The purpose of this study was to research the management of the recurrent cerebral aneurysm after a surgical clipping and how to overcome them.METHODS: From January 1996 to December 2015, medical records and radiologic findings of 14 patients with recurrent aneurysm after surgical clipping were reviewed retrospectively. Detailed case-by-case analysis was performed based on preoperative, postoperative and follow-up radiologic examinations and operative findings. All clinical variables including age, sex, aneurysm size and location, type and number of applied clips, prognosis, and time to recurrence are evaluated. All patients are classified by causes of the recurrence. Possible risk factors that could contribute to those causes and overcoming ways are comprehensively discussed.RESULTS: All recurrent aneurysms after surgical clipping were 14 of 2364 (0.5%). Three cases were males and 11 cases were females. Mean age was 52.3. At first treatment, nine cases were ruptured aneurysms, four cases were unruptured aneurysms, and one case was unknown. Locations of recurrent aneurysm were determined; anterior communicating artery (A-com) (n=7), posterior communicating artery (P-com) (n=3), middle cerebral artery (n=2), anterior cerebral artery (n=1) and basilar artery (n=1). As treatment of the recurrence, 11 cases were treated by surgical clipping and three cases were treated by endovascular coil embolization. Three cases of all 14 cases occurred in a month after the initial treatment. Eleven cases occurred after a longer interval, and three of them occurred after 15 years. By analyzing radiographs and operative findings, several main causes of the recurrent cerebral aneurysm were found. One case was incomplete clipping, five cases were clip slippage, and eight cases were fragility of vessel wall near the clip edge.CONCLUSION: This study revealed main causes of the recurrent aneurysm and contributing risk factors to be controlled. To manage those risk factors and ultimately prevent the recurrent aneurysm, neurosurgeons have to be careful in the technical aspect during surgery for a complete clipping without a slippage. Even in a perfect surgery, an aneurysm may recur at the clip site due to a hemodynamic change over years. Therefore, all patients must be followed up by imaging for a long period of time.
Subject(s)
Female , Humans , Male , Aneurysm , Aneurysm, Ruptured , Anterior Cerebral Artery , Arteries , Basilar Artery , Embolization, Therapeutic , Follow-Up Studies , Hemodynamics , Intracranial Aneurysm , Medical Records , Middle Cerebral Artery , Neurosurgeons , Prognosis , Recurrence , Retrospective Studies , Risk Factors , Surgical InstrumentsABSTRACT
OBJECTIVE: Surgical clipping of the cerebral aenurysm is considered as a standard therapy with endovascular coil embolization. The surgical clipping is known to be superior to the endovascular coil embolization in terms of recurrent rate. However, a recurrent aneurysm which is initially treated by surgical clipping is difficult to handle. The purpose of this study was to research the management of the recurrent cerebral aneurysm after a surgical clipping and how to overcome them. METHODS: From January 1996 to December 2015, medical records and radiologic findings of 14 patients with recurrent aneurysm after surgical clipping were reviewed retrospectively. Detailed case-by-case analysis was performed based on preoperative, postoperative and follow-up radiologic examinations and operative findings. All clinical variables including age, sex, aneurysm size and location, type and number of applied clips, prognosis, and time to recurrence are evaluated. All patients are classified by causes of the recurrence. Possible risk factors that could contribute to those causes and overcoming ways are comprehensively discussed. RESULTS: All recurrent aneurysms after surgical clipping were 14 of 2364 (0.5%). Three cases were males and 11 cases were females. Mean age was 52.3. At first treatment, nine cases were ruptured aneurysms, four cases were unruptured aneurysms, and one case was unknown. Locations of recurrent aneurysm were determined; anterior communicating artery (A-com) (n=7), posterior communicating artery (P-com) (n=3), middle cerebral artery (n=2), anterior cerebral artery (n=1) and basilar artery (n=1). As treatment of the recurrence, 11 cases were treated by surgical clipping and three cases were treated by endovascular coil embolization. Three cases of all 14 cases occurred in a month after the initial treatment. Eleven cases occurred after a longer interval, and three of them occurred after 15 years. By analyzing radiographs and operative findings, several main causes of the recurrent cerebral aneurysm were found. One case was incomplete clipping, five cases were clip slippage, and eight cases were fragility of vessel wall near the clip edge. CONCLUSION: This study revealed main causes of the recurrent aneurysm and contributing risk factors to be controlled. To manage those risk factors and ultimately prevent the recurrent aneurysm, neurosurgeons have to be careful in the technical aspect during surgery for a complete clipping without a slippage. Even in a perfect surgery, an aneurysm may recur at the clip site due to a hemodynamic change over years. Therefore, all patients must be followed up by imaging for a long period of time.
Subject(s)
Female , Humans , Male , Aneurysm , Aneurysm, Ruptured , Anterior Cerebral Artery , Arteries , Basilar Artery , Embolization, Therapeutic , Follow-Up Studies , Hemodynamics , Intracranial Aneurysm , Medical Records , Middle Cerebral Artery , Neurosurgeons , Prognosis , Recurrence , Retrospective Studies , Risk Factors , Surgical InstrumentsABSTRACT
Behçet's disease is an inflammatory disorder involving multiple organs. Its cause is still unknown, but vasculitis is the major pathologic characteristic. The common vascular lesions associated with Behçet's disease are aneurysm formation, arterial or venous occlusive diseases, and varices. Arterial aneurysms mostly occur in large arteries. Intracranial aneurysms hardly occur with Behçet's disease. We would like to present a 41-year-old female patient with Behçet's disease who showed symptoms of severe headache due to subarachnoid hemorrhage. Brain computed tomography revealed multiple aneurysms. We also present a literature review of intracranial arterial aneurysms associated with Behçet's disease.
Subject(s)
Adult , Female , Humans , Aneurysm , Arteries , Brain , Headache , Intracranial Aneurysm , Subarachnoid Hemorrhage , Varicose Veins , VasculitisABSTRACT
OBJECTIVE: Screw fixation via the paraspinal muscle sparing approach and by percutaneous screw fixation are known to diminish the risk of complications, such as, iatrogenic muscle injury as compared with the conventional midline approach. The purpose of this study was to evaluate tissue injury markers after these less traumatic screw fixation techniques for the treatment of L4-L5 spondylolisthesis. METHODS: Twenty-two patients scheduled for posterior lumbar interbody fusion (PLIF) at the L4-L5 segment for spondylolisthesis were prospectively studied. Patients were divided into two groups by screw fixation technique (Group I: paraspinal muscle sparing approach and Group II: percutaneous screw fixation). Levels of serum enzymes representing muscle injury (CK-MM and Troponin C type 2 fast), pro-inflammatory cytokine (IL-8), and anti-inflammatory cytokine (IL-1ra) were analyzed using ELISA techniques on the day of the surgery and 1, 3, and 7 days after the surgery. RESULTS: Serum CK-MM, Troponic C type 2 fast (TNNC2), and IL-1ra levels were significantly elevated in Group I on postoperative day 1 and 3, and returned to preoperative levels on postoperative day 7. No significant intergroup difference was found between IL-8 levels despite higher concentrations in Group I on postoperative day 1 and 3. CONCLUSION: This study shows that percutaneous screw fixation procedure is the preferable minimally invasive technique in terms of minimizing muscle injury associated with L4-L5 spondylolisthesis.
Subject(s)
Humans , Enzyme-Linked Immunosorbent Assay , Interleukin 1 Receptor Antagonist Protein , Interleukin-8 , Muscles , Prospective Studies , Spondylolisthesis , Troponin CABSTRACT
OBJECTIVE: The purpose of this study was to perform a clinical analysis of nine patients with giant aneurysms managed with endovascular embolization. METHODS: From March 2000 to September 2009, nine cases of giant intracranial aneurysms were treated (five unruptured and four ruptured). The nine patients included two males and seven females who were 47 to 72 years old (mean, 59.2 years old). The types of giant intracranial aneurysms were eight internal carotid artery aneurysms and one vertebral artery aneurysm. Treatment for each aneurysm was chosen based on anatomic relationships, aneurysmal factors, and the patients' clinical state. Three patients underwent endovascular coiling with stent and six initially underwent endovascular coiling alone. Medical records, operation records, postoperative angiographies, and follow-up angiographies were reviewed retrospectively. RESULTS: Eight out of nine patients showed good clinical outcomes. (six were excellent and two were good) after a mean follow-up period of 27.9 months. Six (67%) of the nine patients had a near-complete occlusions on the post-operative angiogram (mean, 13.5 months after the procedure). Occlusion rates of 90% or higher were obtained for eight (89%) of all the patients. One patient died due to multiple organ failure. Stents were ultimately required at some point for managing four aneurysms. Two patients needed additional procedures because of aneurysm regrowth. CONCLUSION: Endovascular treatment could be an alternative option for managing giant aneurysms adjuvant to surgical intervention.
Subject(s)
Female , Humans , Male , Aneurysm , Angiography , Carotid Artery, Internal , Follow-Up Studies , Intracranial Aneurysm , Medical Records , Multiple Organ Failure , Stents , Vertebral ArteryABSTRACT
OBJECTIVE: This study was performed to describe the clinical presentation, surgical outcome in patients with symptomatic myelopathy caused by ossification of the yellow ligament (OYL). METHODS: The authors reviewed consequent 12 patients in whom posterior decompressive laminectomies were performed for OYL from 1999 to 2005. Diagnostic imagings including simple radiographs, computed tomography and magnetic resonance images were performed in each case. The patients were reviewed to evaluate the clinical presentation, surgical outcome and complications of the operation. RESULTS: In all patients, OYL was located in the lower thoracic region and all patients presented with numbness on both limbs and pain. Among them, 5 patients presented with gait disturbance due to paraparesis and two patients had sphincter dysfunction. Decompressive laminectomy through a posterior approach using microscope resulted in improvement of symptoms in all patients, but, recovery was incomplete in a half of the patients. The mean postoperative Japanese orthopaedics association (JOA) score was 7.9 when compared with 4.9 in preoperative assessment and the mean recovery rate was 65%. Dural tear was noticed in four patients, so dural repair was performed, but there were no neurological deficits related to neural injury. CONCLUSION: OYL is an uncommon cause of myelopathy but it can lead to debilitating thoracic myelopathy. Careful decompressive laminectomy can achieve favorable results.
Subject(s)
Humans , Asian People , Extremities , Gait , Hypesthesia , Laminectomy , Ligaments , Magnetic Resonance Spectroscopy , Paraparesis , Spinal Cord DiseasesABSTRACT
OBJECTIVE: The incidence of subarachnoid hemorrhage (SAH) worldwide varies considerably. In spite of many reports about the incidence of SAH, there has been no report about the incidence of SAH on the basis of the Korean population. The purpose of this hospital-based study was to assess the actual incidence rates of aneurysmal SAH in Gwangju city and Jeollanamdo province. METHODS: All cases of SAH confirmed by computerized tomography (CT) between January 2007 and December 2007 were selected for analysis. For the data collection, three major training hospital and ten general hospitals working the CT in Gwangju city and four major general hospitals in Jeollanamdo province participate in this study. RESULTS: According to the official census of Korea, the population was 1,413,444 in Gwangju city and 1,929,836 in Jeollanamdo province in 2007. There were 163 patients in Gwangju city and 266 patients in Jeollanamdo province confirmed SAH by CT in 2007. The crude and the age- and sex-adjusted annual incidence rates per 100,000 population for all ages in Gwangju city were 11.5 and 12.4 for aneurysmal SAH and in Jeollanamdo province were 13.8 and 10.8. The incidence was higher in women and increased with age. The gender distribution varied with age. At young ages, the incidence was higher in men while after the age of 40 years, the incidence was higher in women. CONCLUSION: In the present study, the age- and sex-adjusted annual incidence rates is 11.8 in Gwangju city and Jeollanamdo province. The incidence was higher in women and increased with age.
Subject(s)
Female , Humans , Male , Aneurysm , Censuses , Data Collection , Hospitals, General , Incidence , Korea , Risk Factors , Subarachnoid HemorrhageABSTRACT
OBJECTIVE: The objective is to describe the relationship of anatomical landmark required for the middle fossa approach to preservation of hearing. METHODS: Dissection of 16 fixed human cadaveric heads was performed. we identified a rhomboid-shaped middle fossa landmarks that serve as a guide to minimize cochlea injury. The points of this construct are as follows ; 1) the junction of the greater superficial petrosal nerve and the trigeminal nerve ; 2) the lateral edge of the porus trigemius ; 3) the intersection of the petrous ridge and arcuate eminence ; and 4) the intersection of the lines extended along the axes of the greater superficial petrosal nerve and arcuate eminence. Mean, minimum, and maximum measurements of all distances were determined. RESULTS: The average cochlea-geniculate ganglion distance measured in the dissected specimens was 3.0+/-0.8mm with a range of 1.2 to 4.1mm. The average cochlea-petrous carotid genu distance was 2.9+/-0.9mm with a range of 1.2 to 4.0mm. The average cochlea-internal acoustic meatus distance measured in the dissected specimens was 9.0+/-0.5mm with a range of 7.8-10.9mm. The average cochlea-mandibular nerve distance measured was 9.4+/-0.4mm with a range of 7.6-11.3mm. CONCLUSION: The middle fossa approach requires special knowledge of the anantomy to reduce the risk of damage to cochlea. It is important that the surgeon understand the surgical anantomy. The present study describes the simple geometric construct that proposes to assist in locating the cochlea.
Subject(s)
Humans , Acoustics , Cadaver , Cochlea , Ganglion Cysts , Head , Hearing , Trigeminal NerveABSTRACT
OBJECTIVE: Despite advances in both operative techniques (endovascular coiling or surgical neck clipping), management of basilar artery aneurysms has not been completed. The goal of this retrospective study is to evaluate endovascular coiling compared with surgical neck clipping of upper basilar artery aneurysms. METHODS: From january of 1990 to December of 2001, the authors treated 31 cases of upper basilar artery aneuryms. Among of those upper basilar artery aneurysms, 22 patients received surgical neck clipping and 9 patients recevied non-surgical endovascular coiling. Results from outpatient follow-ups for 12 months after operation were classified with Glasgow outcome scale (GOS) analyzed respectively. RESULTS: Overall, 11(50%) of the surgical neck clipping patients and 6(66.7%) in endovascular coiling patients were showed good outcomes(GOS 4~5). Morbidity of the surgical clipping is about 22.7%(5/22) and the endovascular coiling is about 22.2%(2/9) There were two death in the surgical clipping group due to vasospasm and brain stem infarction, but none in the endovascular coiling group. The major causes of surgical morbidity were direct brain damage, perforator occlusions, vasospasm and meningitis. Endovascular coiling group was shorter hospital stay and lesser hospital expenses than surgical neck clipping group. CONCLUSION: Non-surgical endovascular coiling of upper basilar artery aneurysms is considered to be useful alternative treatment in improving short-term prognosis(12 months follow-ups) and reducing medical expenses compared to surgical neck clipping although long-term follow-up is needed.
Subject(s)
Humans , Basilar Artery , Brain , Brain Stem Infarctions , Follow-Up Studies , Glasgow Outcome Scale , Intracranial Aneurysm , Length of Stay , Meningitis , Neck , Outpatients , Retrospective Studies , Surgical InstrumentsABSTRACT
OBJECTIVE: Epigallocatethin gallate(EGCG) is a major green tea polyphenol and is known to have potent antioxidative and antiproliferative actions. This study is performed to investigate the antioxidative effect of EGCG on the various oxidative insults in mouse cerebral cortical cell cultures. METHODS: Mixed cortical cell cultures containing both neuron and glia prepared by plating fetal mice cortical cells on to an established glia of 24 well vessels. At 13-15 days in vitro, oxidative neuronal deaths were induced by the addition of oxidants into the cortical cultures. Iron ion(FeCl2), copper ion(CuCl2), sodium nitroprusside(SNP) and buthionine sulfoximine(BSO, a glutathione depletor) were used as oxidants. Cell death was assessed by LDH assay after microscopic examination. RESULTS: All four oxidants induced neuronal cell death associated with cell body swelling, which was markedly inhibited by Trolox(100muM), a vitamin E analog. EGCG(1-10muM) markedly inhibited the neuronal cell death induced by 20muM CuCl2, 1muM SNP, or 1mM BSO. Unexpectedly the neuronal cell death induced by 20muM FeCl2 was augmented by treatment with 1 or 3muM EGCG. EGCG itself induced concentration- and exposure time-dependent cell death at more than 30muM concentrations. EGCG(30, 100muM) injured not only neuronal cells but glial cells after 48 hour exposure. The EGCG-induced cytotoxicity was partially inhibited by protein synthesis inhibitors, cycloheximide(0.1 or 1mug/ml) and emetine (1mug/ml) or high potassium media(10 or 25mM) but was not affected by Trolox. CONCLUSION: These results suggest that the dual antioxidative-cytotoxic actions of EGCG are concentration-dependent and that the antioxidative aciton depends on the kind of oxidative insults, and that the EGCG-induced cytotoxicity be relevant to protein synthesis and/or membrane depolarization.
Subject(s)
Animals , Mice , Cell Culture Techniques , Cell Death , Copper , Emetine , Glutathione , Iron , Membranes , Neuroglia , Neurons , Oxidants , Potassium , Protein Synthesis Inhibitors , Sodium , Tea , Vitamin E , VitaminsABSTRACT
The authors report on an endovascular experience using electrically detachable coils and direct clipping for the treatment of ruptured irregularly shaped aneurysms associated with pseudo-sac formation in a thrombotic cavity at the rupture site. These aneurysms might be fragile and associated with a high possibility of repeated rupture, especially, during an endovascular and direct clipping procedures. Between March 1998 and August 2001, 298 aneurysm patients underwent operations at our hospital. Among these patients, 4 patients showed pseudo-sac formation in a thrombotic cavity at the aneurysm rupture site, and were treated using an early endovascular occlusion technique or direct clipping after diagnostic angiography. These aneurysms showed delayed opacification and delayed washout of contrast medium from the irregularly shaped portion of the aneurysm on digital subtraction angiography. Moreover these aneurysms tend to rerupture during GDC embolization because of the fragile pseudoaneurysmal thrombotic cavity at the rupture point. Ruptured aneurysm with pseudo-sac formation in thrombotic cavity display delayed and irregularly shaped filling and retention of contrast medium at the rupture point. Early treatment of these aneurysms prevents rebleeding from the pseudo-sac in the thrombotic cavity at the ruptured site.
Subject(s)
Humans , Aneurysm , Aneurysm, False , Aneurysm, Ruptured , Angiography , Angiography, Digital Subtraction , RuptureABSTRACT
OBJECTIVE: The authors present the results of management outcomes for upper basilar artery aneurysms via transclinoidal approach. METHODS: Clinical and angiographic evaluations were performed in twenty two consecutive patients with upper basilar artery aneurysms(three of them had superior cerebellar artery aneurysms) treated by surgery via transclinoidal approach between January, 1990 and April, 2000. RESULTS: Of the 22 patients, fifteen patients had multiple aneurysms including basilar bifurcation aneurysms and basilar-superior cerebellar aneurysms. Seventy seven percent were in good preoperative neurological status(H-H grade I-III), 23% were in poor grade(H-H grade IV). The management outcome was:Glasgow outcome scale(GOS) I 54.5%, GOS II 18%, GOS III 13.6%, GOS IV 4.5% and GOS V(death) 9%. The major causes of morbidity were direct brain damage, perforator occlusion, vasospasm and meningitis. CONCLUSION: The management outcome of upper basilar artery aneurysms treated via clinoidectomy was good(72.5%). Transclinoidal approach is an acceptable alternative for upper basilar artery aneurysms.
Subject(s)
Humans , Aneurysm , Arteries , Basilar Artery , Brain , Intracranial Aneurysm , MeningitisABSTRACT
The mortality of patients with brain abscess has decreased significaltly. This has been attributed to improved diagnostic imaging, the evolution of neurosurgical techniques and understanding of intracranial pressure pathophysiology, greater critical care understanding, and newer antibiotics. However, the mortality associated with intraventricular rupture of brain abscess remained consistently high at or above 80% once identified. A case of intraventicular rupture of thalamic abscess with good quality of survival is presented based on aggressive 4-component therapeutic plan used. The four components are 1) extraventricular drainage for 6 weeks, 2) lavage of the ventricular system using closed irrigation system, 3) intravenous antibiotics, 4) intraventricular gentamicin and vancomycin, twice and once daily, respectively.
Subject(s)
Humans , Abscess , Anti-Bacterial Agents , Brain Abscess , Critical Care , Diagnostic Imaging , Drainage , Gentamicins , Intracranial Pressure , Mortality , Rupture , Thalamus , Therapeutic Irrigation , VancomycinABSTRACT
A rare case of tenosynovial giant cell tumor of invading left temporomandibular joint(TMJ) extending the middle cranial fossa is reported. Report of this entity in the temporomandibular joint is rare. A 39-year old male patient presented with mild discomfort and swelling in preauricular area. MR image demonstrated a destructive lesion of the left TMJ, with bony erosion of temporal bone and extension into middle cranial fossa. The patient underwent radiotherapy as adjuvant therapy to prevent recurrence, followed by resection. The histological and radiological features of this tumor are discussed along with a brief description of the disease entity.
Subject(s)
Adult , Humans , Male , Cranial Fossa, Middle , Giant Cell Tumors , Giant Cells , Radiotherapy , Recurrence , Temporal Bone , Temporomandibular JointABSTRACT
Fifty-two patients with unstable cervical spine injuries underwent operations between January 1, 1990 to June 30, 1997 in our institution and this is retrospective study on clinical results about these patients. Patients with cervical instability resulted from injury posterior column, being included in White's criteria, were treated with Hafifax interlaminar clamps for cervical instability. We followed up forty-two cases for more than one year. All of the forty- two cervical fixations showed immediate and long term stability and there were no neurological complication. Neu rologic improvements were seen in thirty three, but thirteen cases were unchanged. These results indicate that Halifax interlaminar clamps are consider to be a safe and effective method for posterior stabilization of va rious causes of cervical spine instability.
Subject(s)
Humans , Retrospective Studies , SpineABSTRACT
Cerebral ependymal cysts are very rare. About 30 cases have been reported in the literature. They mimic arachnoid cysts clinically and on imaging studies but are different from arachnoid cysts in pathological findings. They are believed to arise by the sequestration of a small segment of the primitive ependymal lining into either the cortical mantle or the perimedullary mesh. They occupy the central white matter of the frontal or temporoparietal lobes. The authors describe a case of septate ependymal cyst involving left sylvian fissure. The clinicopathological features, treatment, and results of previously reported cases are reviewed, and the etiology and pathogenesis of these cysts are discussed.
Subject(s)
Arachnoid CystsABSTRACT
Microcystic meningioma, a distinct morphological variant of meningiomas, is histologically characterized by a vacuolated appearance with multiple cystic spaces lined by vacuolated or stellate-shaped tumor cells. This unusual variant was originally described by Masson, who labeled it "humid". The clinical and morphological findings point toward a benign course. And these unusual morphological variants of meningioma are potentially curable tumor. But there is no definitive method for preoperatively differentiating microcystic meningioma from the malignant glioma. We report a case of microcystic meningioma occurring in the left frontal area of 74 year old woman, with malignant clinical nature.
Subject(s)
Aged , Female , Humans , Glioma , MeningiomaABSTRACT
Seasonal and climatic variations have been linked to the occurrence of some types of cerebrovascular disease. However, the conditions that lead to intracranial aneurysm rupture are not known. The purpose of the present study was to determine whether predisposing factors are more related to intracranial aneurysm rupture and to determine relation of the stressful condition to intracranial aneurysm rupture. In order to determine the predisposing factors, the authors have examined the relationship between seasonal variation and predisposing factors of cerebral aneurysm. The author investigated activities of the patients and events as well as diurnal and seasonal variations in the onset of subarachnoid hemorrhage(SAH) in 336 consecutive patients. The results showed that the onset of SAH was associated with working in 11.0%, defecation and/or urination in 8.3%, sleeping in 6.9% and 4.2% walking. Hypertensive patients in aneurysmal rupture was 36.0%. Subarachnoid hemorrhage occurred during stressful events in 36.3% of the patients, during nonstreneous events in 34.8% and during rest or sleep in 9.8%. The activities or events preceding subarachnoid hemorrhage were not known in the remaining 18.8%. Men were more likely to have suffered their hemorrhages during stressful events than women(47% vs 30%). Peak times of intracranial aneurysm rupture usually occurred from 6 to 11 A.M.(36.0%) and from 4 to 6 P.M.(20.5%). The seasonal variation of the onset of SAH showed the incidence to be slightly higher in winter than in any other seasons. We concluded that the occurrence of subarachnoid hemorrhage display seasonal and diurnal variation. And the precipitation of aneurysmal rupture have two important factors; increased arterial blood pressure and decreased cerebrospinal fluid pressure around the aneurysm. Also, the onset of the subarachnoid hemorrhage is related to the physiological circadian periodicity of blood pressure, climatic change and stressful events.