自发性低颅压并发静脉血栓形成和出血性梗死一例临床分析

目的自发性低颅压(SIH)多以与体位相关的剧烈头痛为主要症状,误诊率高。SIH并发静脉和(或)静脉窦血栓形成非常罕见。方法我们报道1例SIH并发静脉血栓形成和出血性梗死的患者,并复习相关文献。结果本例患者自发性低颅压在前,静脉血栓形成和出血性梗死在后,同时经过检查排除了其他可导致静脉血栓形成的危险因素。所以我们考虑SIH是静脉血栓形成的危险因素。假如SIH患者与体位相关的间断的头痛变成持续性头痛时,应考虑到有静脉血栓形成的可能。结论因为SIH的患者有形成硬膜下血肿的风险,所以对于静脉血栓形成的抗凝治疗应谨慎。     

Headache attributed to spontaneous intracranial hypotension

Recent evidence suggests that spontaneous intracranial hypotension (SIH) is not as rare as previously thought. Orthostatic headache is the prototypical manifestation of SIH, but various headache syndromes have also been reported such as migraine-like headache, tension-type headache and non-specific headaches among the others. The International Headache Society (IHS) has recently proposed diagnostic criteria for headache attributed to SIH. Seventy patients consecutively seen at our institution between 1993 and 2005 and diagnosed with SIH were included in the study. SIH diagnosis was confirmed in all patients by brain-enhanced MRI: 23 were males (33%), 47 females (77%) and mean age was 45 years (range 18–69). Follow-up: median value 35 months (range: 8 months-14 years). Time between symptom onset and diagnosis was 4 months (median) (range 15 days-45 months). The IHS (2004) criteria for “Headache attributed to SIH” were applied. Typical brain imaging findings confirmed the diagnosis of SIH in all patients: criteria B and C were fulfilled in all patients. Criterion A of the IHS classification was not fulfilled in 34 (49%) patients. Sixty-two (89%) patients did not fulfil criterion D of the IHS classification; 28 (40%) did not fulfil both criterion A and D. So far, only 2 (3%) fulfilled all IHS criteria for headache attributed to SIH. The IHS criteria for headache attributed to SIH could not classify the headache in most of our SIH patients. A revision of the IHS criteria for headache attributed to SIH is necessary.     

Two cases of spontaneous intracranial hypotension associated with chronic subdural hematoma only treated with burr hole irrigation of the hematomas]

We reported two cases of spontaneous intracranial hypotension (SIH) associated with bilateral chronic subdural hematoma (CSDH). The patients presented with severe positional headache, aggravated by sitting or standing. Neither spinal surgery nor lumbar-tap had been performed in these patients. They were diagnosed as SIH with bilateral CSDH. Headache was aggravated and CSDHs volume increased despite conservative therapy. However, after a burr hole irrigation of hematoma, not only CSDHs but also the symptoms with SIH were completely resolved and there was no recurrence. We demonstrated that burr hole irrigation for CSDH associated with SIH might completely resolve the SIH symptom in some cases, as in the present report. The mechanism of this phenomenon was discussed.     

Subdural haematoma: a potentially serious consequence of spontaneous intracranial hypotension

BACKGROUND: Spontaneous intracranial hypotension (SIH) is characterised by postural headache and low opening pressure at lumbar puncture without obvious cause. Cranial magnetic resonance imaging often shows small subdural collections without mass effect, dural enhancement, venous sinus dilatation, or downward displacement of the brain. The condition is thought to be benign. OBJECTIVES: To evaluate the incidence of subdural haematoma as a serious complication of SIH. METHODS: A prospective survey of all cases of SIH presenting to a large neuroscience unit over a two year period. RESULTS: Nine cases of SIH were seen. Four of these were complicated by acute clinical deterioration with reduced conscious level because of large subdural haematomas requiring urgent neurosurgical drainage. CONCLUSIONS: SIH should not be considered a benign condition. Acute deterioration of patients' clinical status may occur secondary to large subdural haematomas, requiring urgent neurosurgical intervention.     

Dural sinus thrombosis in spontaneous intracranial hypotension

Dural sinus thrombosis (DST) is rarely associated with spontaneous intracranial hypotension (SIH). Engorgement of the venous system, caused by the CSF loss that occurs in SIH, is considered to favour the thrombosis, although signs of both SIH and DST are usually seen simultaneously at the first diagnostic MRI. We observed two patients with SIH and DST. Changes in pattern of headaches and MRI findings demonstrated that DST followed SIH. In SIH, the velocity of the blood flow in the dural sinuses may be reduced because of dilatation of the venous system which compensates the CSF loss. Other possible mechanisms seem unlikely on the grounds of both clinical presentation and MRI studies. Received in revised form: 6 December 2005     

The stress-induced hyperthermia paradigm as a physiological animal model for anxiety: a review of pharmacological and genetic studies in the mouse

This paper reviews the function, brain mechanisms and pharmacology of stress-induced hyperthermia (SIH) in a broad context. Hyperthermia itself is induced by all stressful stimuli and can be found across numerous species, including humans. As a model for anxiety, the process of insertion of a rectal probe increases temperature ranging from about 0.5-1.5 degrees C in 10-15min is called SIH. This temperature increase can be blocked by anxiolytic drugs. The methodological as well as pharmacological aspects of the group- (G-SIH) and singly housed (SIH) version of the paradigm are described in detail. Also, an overview is presented about studies using the SIH procedure in genetically modified mice together with the potential interference with immunological induction of a febrile response. The paper also presents data that highlight some of the limitations of the SIH procedure for use of drugs like nicotine, which contain particular characteristics such as short in vivo half-life, and/or disturbance of thermoregulation. The advantages and disadvantages of the SIH procedure as a physiological model of anxiety are discussed.     

Pseudo-subarachnoid hemorrhage: A potential imaging pitfall associated with spontaneous intracranial hypotension

Objective

(1) To determine the frequency of CT mimics of subarachnoid hemorrhage (SAH) in a large cohort of subjects with spontaneous intracranial hypotension (SIH). (2) To emphasize the distinctive radiologic features of SIH.

Patients and methods

CT scans of 95 subjects with SIH were retrieved and reviewed to search for findings of pseudo-SAH (CT mimics of SAH in the absence of blood).

Results

Pseudo-SAH radiologic findings (increased attenuation in the basilar cisterns, sylvian fissures, or along the tentorium) were detected on CT scans of 10 of the 95 SIH subjects. However, on MRI scans, these subjects exhibited the typical SIH abnormalities (diffuse pachymeningeal enhancement and brain sagging with obliteration of basilar cisterns).

Conclusions

In the emergency room, SIH should be considered in the differential diagnosis between SAH and pseudo-SAH. Although SIH and SAH can share some radiologic features, SIH has distinctive MRI and CT findings. Their recognition should obviate the need for more invasive procedures (e.g., cerebral angiography) to definitely rule out SAH and an aneurismal source of bleeding.     

Subdural hematoma in a patient with spontaneous intracranial hypotension and cerebral venous thrombosis

We report a patient with clinical and neuroimaging findings of spontaneous intracranial hypotension (SIH) who developed cerebral venous thrombosis (CVT). An association between SIH and CVT has rarely been observed. Anticoagulation therapy was administered. The clinical course was subsequently complicated by a large subdural hematoma that required neurosurgical evacuation. The present report indicates that SIH should not be always considered a benign condition, especially when associated with CVT and subdural fluid collections. Furthermore, clinicians should be aware of the potential risks of anticoagulant therapy in patients with SIH and CVT.     

Spontaneous intracranial hypotension: correlation of imaging findings with clinical features

BACKGROUND: Spontaneous intracranial hypotension (SIH) is increasingly recognized as a clinically variable and likely underdiagnosed syndrome caused by non-traumatic CSF leaks. The aim of this study was to correlate the findings of imaging studies - magnetic resonance imaging (MRI), radionuclide cisternography - with clinical features and CSF pressure in SIH in order to improve the diagnostic yield and management in patients with SIH. METHODS: Clinical case study of 10 consecutive cases of SIH, MRI, radio-isotope cisternography. RESULTS: 5 out of 10 patients had unusual clinical symptoms of SIH(2 subdural haematomas, 1 gait ataxia, 1 tinnitus, 1 haemodialysis-associated headache). In 7 patients pachymeningeal gadolinium enhancement was detected in MRI accompanied by a reduced CSF opening pressure. In contrast, the 3 patients with normal MRI also had a normal CSF pressure. Radio-isotope cisternography was abnormal in all patients tested. There was no correlation between the severity of clinical symptoms and MRI or radionuclide cisternography findings. CONCLUSIONS: The spectrum of clinical symptoms and imaging findings in SIH is highly variable. There- fore the diagnosis of SIH is often delayed. Radio-isotope cisternography is an important additional diagnostic method to detect CSF leaks or pathological kinetics of radio-isotope movement particularly in cases with normal MRI findings.     

Spontaneous intracranial hypotension: case report]

Intracranial hypotension (IH) is a rare cause of acute headache. There are secondary IH (more frequently, after lumbar puncture, head and back trauma, brain and spine surgery) and essential (spontaneous intracranial hypotension SIH). SIH was first described by Schaltenbrand in 1938. This syndrome is characterized mainly by acute postural headache. The authors report a case of 45-year-old women with SIH. Clinical diagnosis was confirmed by lumbar puncture and characteristic MR. The symptoms completely regressed within 2 weeks. The treatment was based on bed rest, hypotonic solutions, steroids, caffeine. Pathophysiology, diagnosis and treatment of SIH are discussed.     

Clinical and neuroradiological features of spontaneous intracranial hypotension: report of two cases]

We report two patients with spontaneous intracranial hypotension (SIH) showing bilateral subdural hematoma. One of the two patients was a 32-year-old woman, and the other was a 27-year-old healthy woman. Both patients presented chronic, intractable, orthostatic headache with dizziness and nausea. In both patients, both general and neurological examinations were normal, and routine laboratory tests were all normal, except for dry taps of the lumbar puncture. Brain CT scans and MRI revealed thin, bilateral subdural hematomas. RI-cisternography and CT-myelography disclosed multiple extraspinal CSF leakages along the nerve root sheathes of the cervical segments and early bladder filling of the radionucleotides in both patients. These findings support an emerging hypothesis that the extraspinal CSF leakage may play a role for inducing SIH. Anatomical fragility around the nerve sheath, especially that of the lower cervical segments, may contribute to the pathophysiological mechanism underlying SIH. For making a prompt diagnosis of SIH and for the better understanding of the pathophysiological mechanism of SIH, RI-cisternography of the whole spinal segments is important.     

Leptin suppresses semi-starvation induced hyperactivity in rats: implications for anorexia nervosa

Semi-starvation induced hyperactivity (SIH) occurs in rodents upon caloric restriction. We hypothesized that SIH is triggered by the decline in leptin secretion associated with food restriction. To test this hypothesis, rats, which had established a stable level of activity, were treated with leptin or vehicle via implanted minipumps concomitantly to initiation of food restriction for 7 days. In a second experiment treatment was initiated after SIH had already set in. In contrast to the vehicle-treated rats, which increased their baseline activity level by 300%, the development of SIH was suppressed by leptin. Furthermore, leptin was able to stop SIH, after it had set in. These results underscore the assumed major role of leptin in the adaptation to semi-starvation. Because SIH has been viewed as a model for anorexia nervosa, we also assessed subjective ratings of motor restlessness in 30 patients with this eating disorder in the emaciated state associated with hypoleptinemia and after increments in leptin secretion brought upon by therapeutically induced weight gain. Hypoleptinemic patients ranked their motor restlessness higher than upon attainment of their maximal leptin level during inpatient treatment. Thus, hypoleptinemia might also contribute to the hyperactivity frequently associated with anorexia nervosa.     

自发性脑室出血对下丘脑-垂体轴功能的影响

目的探讨自发性脑室出血对下丘脑-垂体轴功能的影响。方法对32例自发性脑室出血病人(脑室出血组)出血后1、14、30 d的血清胰岛素样生长因子-1(IGF-1)、促肾上腺皮质激素(ACTH)、泌乳素、卵泡刺激素(FSH)、黄体生成素(LH)、游离甲状腺素(FT4)、促甲状腺素(TSH)水平进行测定,并与21例健康成年人(正常对照组)相应激素水平进行比较,对自发性脑室出血病人激素异常情况及其动态变化进行分析。结果自发性脑室出血病人中激素分泌异常发生率为40.6%,出血后1 d脑室出血组的激素水平与正常对照组相比差异没有统计学意义(均P>0.05);出血后14 d,与正常对照组相比,脑室出血组IGF-1水平明显降低(P<0.05),泌乳素水平明显上升(P<0.05),且均持续到第30天;ACTH水平在出血后30 d时明显低于正常对照组(P<0.05)。结论脑室出血对下丘脑-垂体轴神经内分泌功能有明显影响。动态监测这类病人神经内分泌变化,必要时采取激素替代治疗可能有助于改善病人的预后及生存质量。     

伴脑膜肥厚的原发性低颅压综合征与肥厚性硬膜炎的临床对比分析

目的探讨伴脑膜肥厚的原发性低颅压综合征(SIH)与肥厚性硬膜炎(HP)的临床特点及鉴别诊断,以提高对低颅压综合征的诊治水平。方法回顾性分析有脑膜肥厚的10例原发性低颅压综合征与10例肥厚性硬膜炎的临床、实验室资料,影像学检查及治疗和转归等。结果两组病人的临床表现、CSF改变及影像学改变有相似之处,但SIH的头痛与体位变化有关,CSF压力明显低于正常,影像学上可有硬膜下积液,治疗主要以补液为主,与HP有区别。结论低颅压综合征与肥厚性硬膜炎虽有相似之处,但两者病因、发病机制和治疗上仍有区别,应注意鉴别,以防误诊。     

Reversible coma: a rare presentation of spontaneous intracranial hypotension

BACKGROUND: Spontaneous intracranial hypotension (SIH) is a well-recognized neurologic disorder that typically presents with orthostatic headaches, low cerebral spinal fluid pressures and distinct abnormalities on magnetic resonance imaging. METHODS: We present a case of a rare presentation of SIH. RESULTS: A 49-year-old man presented with a two week history of orthostatic headaches that rapidly progressed to encephalopathy and coma, requiring intubation. Neuroimaging revealed abnormalities typical of SIH; diffusely enhancing pachymeninges, subdural fluid collections, and descent of the brain. Treatment with an epidural blood patch reversed his coma within minutes. Following a second blood patch, the patient became asymptomatic. No cerebral spinal leak could be identified on magnetic resonance imaging or on a nuclear medicine technetium cerebral spinal fluid flow study. At six month follow-up, he remained symptom free. CONCLUSION: The mechanism of coma in SIH is presumed to be compression of the diencephalon from downward displacement of the brain. Although it is very unusual for patients with SIH to present with coma, it is important to recognize since the coma may be reversible with epidural blood patches.     

Cerebral venous thrombosis caused by spontaneous intracranial hypotension: two cases

The association of spontaneous intracranial hypotension (SIH) with cerebral venous thrombosis (CVT) is rare. We are reporting two new cases. In one case, CVT is extensive concerning three sinuses and bilateral parietal cortical veins and, in the other case, only a cortical vein is involved. Both the patients presented had no thrombosis risk factors. There is certainly a link between these two pathologies. SIH should be considered as a risk factor of CVT. Modification of symptoms of SIH leading to CVT must be known to start early treatment.     

Rebound intracranial hypertension after treatment of spontaneous intracranial hypotension

Spontaneous intracranial hypotension (SIH) is characterized by orthostatic headache and the cause is usually cerebrospinal fluid leaks in spine level. Most patients with SIH have a benign course. Epidural blood patch (EBP) is the treatment of choice when initial conservative managements are ineffective. We reported a patient with SIH diagnosed by using magnetic resonance imaging and radionuclide cisternography. Acute rebound intracranial hypertension developed after EBP and was successfully treated with intravenous osmotic agent.     

Stress-induced hyperthermia in the 5-HT(1A) receptor knockout mouse is normal.

BACKGROUND: Several studies on serotonin 1A (5-HT(1A)) receptor knockout mice in different genetic backgrounds indicate that such mice display a more anxious phenotype than their corresponding wild types. We hypothesized that the 5-HT(1A) receptor knockout mice would show a different phenotype than the wild type mice in the stress-induced hyperthermia (SIH) paradigm, which tests putative anxiolytic effects of drugs. Moreover, on pharmacologic challenges with the 5-HT(1A) receptor agonist flesinoxan we expected an absence of the functional response in knockout mice relative to wild type mice. METHODS: Effects of the 5-HT(1A) receptor agonist flesinoxan, alone or in combination with the 5-HT(1A) receptor antagonist WAY-100635, and the gamma-aminobutyric acid A (GABA(A))-benzodiazepine receptor agonist diazepam were studied in the SIH paradigm in male 129/Sv 5-HT(1A) receptor knockout and wild type mice. In addition, the effects of flesinoxan on plasma corticosterone concentrations were determined. RESULTS: Plasma corticosterone concentrations were dose dependently elevated by flesinoxan in wild type mice but not in knockout mice. Flesinoxan dose dependently decreased SIH in wild type mice but not in knockout mice. The flesinoxan effect in wild type mice was blocked by WAY-100635. Furthermore, diazepam decreased SIH in both genotypes. There were no differences in basic SIH responses between wild type and knockout mice. CONCLUSIONS: 5 -HT(1A) receptor knockout mice display a normal SIH response, and results indicate, based on the SIH, that the GABA(A)-benzodiazepine receptor complex functions normally.     

自发性低颅压综合征31例临床特征和影像学分析

目的 探讨自发性低颅压综合征（SIH）的临床特点和影像学改变.方法 回顾性分析31例SIH患者的临床及影像资料.结果 所有患者均有体位性头痛,可伴有恶心、呕吐、头晕、耳鸣、听力丧失、行走不稳、一过性视物模糊、复视、颈肩部疼痛、颈强直 CSF压力均＜70 mmH2O,蛋白升高12例,WBC增多11例,RBC增多7例 全部患者行头颅CT检查,8例见脑肿胀,脑沟变浅,脑室变窄,临床症状消失后复查均恢复正常 15例行头颅MRI检查,8例行增强检查示硬脑膜弥漫性强化,头颅CT及MRI检查见4例硬膜下积液、2例硬膜下血肿 全部患者采用内科综合疗法,1例行硬膜下血肿清除术,均痊愈.结论 SIH的临床表现多样,体位性头痛是特征性症状,腰穿CSF及头颅MRI检查具有诊断价值 本病预后良好,但少数并发硬膜下血肿.