Subarachnoid Cistern And Cisternal Hemorrhage Play Important Roles In Acute Hydrocephalus After Aneurysmal Subarachnoidhemorrhage

Hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH) is one of the common complications of ruptured intracranial aneurysms, which is divided into acute (0～3 days), subacute (4～13 days) and chronic (14 days) hydrocephalus according to the onset time of aSAH. Hydrocephalus after aSAH refers to hydrocephalus after the occurrence of aneurysm rupture in 3 days, with the incidence rate of 15% to 87%, half of which may spontaneously improve within 24 h and 30%-40% can develop into chronic hydrocephalus that needs for shunting operation and have a great impact on the prognosis of patients with ruptured aneurysms.However, there is a dispute about the risk factors of Hydrocephalus after aSAH currently. At present, a number of studies suggest that acute hydrocephalus after aSAH occurred as a result of many factors. Specific risk factors report variably. According to the risk factors reported in the literature there are more than 10 different kinds, including:intraventricular hemorrhage, cistern hemorrhage, the level of consciousness on admission and Hunt-Hess grade, aneurysm location, age, sex, hypertension, diabetes,re bleeding, Fisher grade, intracerebral hematoma, hyponatremia, cerebral vasospasm, treatment modalities, anti-fibrinolytic therapy and so on. In addition to intraventricular hemorrhage, which is acknowledged risk factor, others are presently controversy.Pathogenesis of aneurysmal acute hydrocephalus is not yet explicitly,which is even controversial in vested in obstruction or communication, and include excessive secretion of cerebrospinal fluid, circulation path blocked,absorption disorders in cerebrospinal fluid etc.Therefore, it is necessary to further explore the pathogenesis and treatment methods of acute hydrocephalus after aSAH.The first part:Subarachnoid cistern and cisternal hemorrhage play important roles in acute hydrocephalus after aneurysmal subarachnoid hemorrhageObjective and Methods:Risk factors and cisternal blood in relation to the development of acute hydrocephalus were studied in 306 consecutive patients with aSAH who were admitted within 72 hours by single factor analysis and multi factor Logistic regression analysis.Results:Acute hydrocephalus was found in 112 (36.60%) of 306 in the retrospective study. We found those factors which were significantly related to acute hydrocephalus as following:intraventricular hemorrhage, a diffuse collection of subarachnoid blood, the site of aneurysm, rebleeding and treatment ways. Using multi factor Logistic regression analysis to predict acute hydrocephalus, the most important variables were intraventricular hemorrhage and the site of aneurysm. The incidence of acute hydrocephalus in the absence of intraventricular hemorrhage aSAH patients was 22.41%.Among those patients, the cores of cistern in interpeduncular cistern and right Sylvius cistern were quite high and were statistically significant compared to non-cute hydrocephalus patients. The cores of right cistern, middle cistern and total subarachnoid cistern in acute hydrocephalus group were also statistically significant higher than non-cute hydrocephalus patients.Conclusion:We concluded that the development of acute hydrocephalus after aSAH was multifactorial. Intraventricular hemorrhage and the site of aneurysm as independent risk factors contributed to the development of acute hydrocephalus. The risk of acute hydrocephalus developing in patients without ventricular blood following ruptured aneurysm was significantly increased in those with a high cisternal score for blood in interpeduncular cistern and right Sylvius cistern.The second part:The efficacy of early lamina terminalis fenestration in treating acute hydrocephalus after aneurismal subarachnoid hemorrhageObjective and Methods:Ninety eight patients of acute hydrocephalus after aneurismal subarachnoid hemorrhage who were treated by early lamina terminalis fenestration were retrospectively analyzed. These cases were divided into two groups, including aneurysm clipping group (42 cases) and lamina terminalis fenestration after aneurysm clipping group (56 cases). The improving rate of acute hydrocephalus and the incidence rate of shunt-dependent hydrocephalus after surgical treatment were compared between three groups.Results:All patients were surgical treatment in 72 hours after aneurysm rupture. Ultimately,45 cases acute hydrocephalus patients acquired improvement and 27 cases developed to chronic hydrocephalus after surgical treatment among 98 patients. The acute hydrocephalus patients in aneurysm clipping group have improved 14 cases (the improvement rate was 33.3%).14 cases developed into shunt-dependent hydrocephalus (the incidence rate was 33.3%). The acute hydrocephalus patients in lamina terminalis fenestration after aneurysm clipping group have improved 32 cases (the improvement rate was57.1%); 13 cases developed into chronic hydrocephalus (and the incidence rate was23.2%). The acute hydrocephalus improvement rate and shunt-dependent hydrocephalus incidence rate in posterior circulation aneurysm group were statistically difference between aneurysm clipping group and lamina terminalis fenestration after aneurysm clipping group (P<0.05).But not in anterior circulation aneurysm group. (P>0.05)Conclusion:The efficacy of early lamina terminalis fenestration in treating acute hydrocephalus after aneurismal subarachnoid hemorrhage was effective in posterior circulation circulation aneurysm.The third part:MRI measurement of sylvian cistern in the middle-agedObjective and Methods:To investigate the presence of asymmetry in both sides of sylvian cistern, the MRI measurements of acreage in both sides were performed, we measured 103 healthy persons’brain MRI to get the data of sylvian cistern.The criteria of research objects incorporated were as follows:1) between the ages of 45 to 55; 2) Head MRI did not see any abnormality; 3) All were right-handed; 4) No other significant underlying diseases. Using Nanfang Hospital imaging systems workstation, we measured sylvian cistern area at all levels on TIM-weighted phases,including six sides with the left of each dimension represented by L1-L6 and the right level marked with R1-R6. Try to outline the sylvian cistern in each level using the mouse and compute the area automatically. Then measure the other side in the same way.Results:During 103 cases of the sylvian cistern level in MRI, the areas (in mm2) of the right side in each level respectively are:R1=115.41±53.60, R2=217.36±76.02, R3=193.44±55.56,R4=181.71±59.42,R5=126.32±34.79,R6=80.15±28.60and Rtotal=914.39±204.69; the areas (in mm2) of the left side respectively are L1=117.73±61.75,L2=179.60±75.43, L3=181.46±55.75, L4=169.27±62.91, L5= 117.65±37.26, L6=76.99±30.64 and Ltotal=842.71±217.83.After we compared each level,we found that the area of the right side in R2,R3,R4,R5,R6 were larger than those of the left side and the area in R1 of the right was smaller than that of the left,including significant differences (P≤0.01) between the right side of R2,R3,R4,R5 and the corresponding left levels. Compared the total area of both sides in the sylvian cistern, the right side was significantly bigger than the left side (P=0.000), with statistical significance.Conclusion:Among the right-handed middle-aged healthy crowd between 45 and 55 years old, the area of the right side sylvian cistern is larger than that of the left side.