Diagnosis Of Intracranial Cystic Lesions Research Articles

Intracranial cystic meningiomas: A series of six patients

ObjectiveAlthough meningiomas are the most common primary non-glial intracranial tumors, cystic meningiomas are quite rare. This study presents six cases in order to discuss the radiological and pathological features of cystic meningiomas. Patients and methodsSix patients with cystic meningiomas were included in the study. All patients underwent a cranial computed tomography scan and magnetic resonance imaging (MRI) evaluation, pre- and postoperatively. ResultsAll patients presented with long standing headache dating back at least two years. There was no gender predominance in our series. Radiological evaluation revealed two parasagittal and two convexity meningiomas located at the frontal region. Two lesions were located at the tuberculum sellae and the foramen magnum. All of the tumors were totally excised (Simpson Grade I or II). Pathology results included meningothelial meningioma in three patients, angiomatous meningioma in two patients, and metaplastic meningioma in one patient. In two patients, the cystic meningiomas were resected with the use of sodium fluorescein (Na-Fl) under a YELLOW 560nm microscope filter. Na-Fl was found to be very useful in demonstrating the brain–tumor interface, and it was especially effective in resecting the cyst wall of the peritumoural cystic meningiomas. None of the patients had any complications, and no recurrences were noted in any of the patients within the mean follow-up period of 51 months (range: 16–102 months). ConclusionIt is important to note MRI changes specific to cystic meningioma and include meningiomas in the differential diagnosis of intracranial cystic lesions. The use of sodium fluorescein (Na-Fl) under a YELLOW 560nm microscope filter is a useful tool to differentiate the brain-tumor interface, as well as to identify the cyst wall in order to fully resect the tumor with the cystic component to avoid recurrence and achieve better clinical results.

Intracranial cystic meningiomas: A series of six patients.

Although meningiomas are the most common primary non-glial intracranial tumors, cystic meningiomas are quite rare. This study presents six cases in order to discuss the radiological and pathological features of cystic meningiomas. Six patients with cystic meningiomas were included in the study. All patients underwent a cranial computed tomography scan and magnetic resonance imaging (MRI) evaluation, pre- and postoperatively. All patients presented with long standing headache dating back at least two years. There was no gender predominance in our series. Radiological evaluation revealed two parasagittal and two convexity meningiomas located at the frontal region. Two lesions were located at the tuberculum sellae and the foramen magnum. All of the tumors were totally excised (Simpson Grade I or II). Pathology results included meningothelial meningioma in three patients, angiomatous meningioma in two patients, and metaplastic meningioma in one patient. In two patients, the cystic meningiomas were resected with the use of sodium fluorescein (Na-Fl) under a YELLOW 560nm microscope filter. Na-Fl was found to be very useful in demonstrating the brain-tumor interface, and it was especially effective in resecting the cyst wall of the peritumoural cystic meningiomas. None of the patients had any complications, and no recurrences were noted in any of the patients within the mean follow-up period of 51 months (range: 16-102 months). It is important to note MRI changes specific to cystic meningioma and include meningiomas in the differential diagnosis of intracranial cystic lesions. The use of sodium fluorescein (Na-Fl) under a YELLOW 560nm microscope filter is a useful tool to differentiate the brain-tumor interface, as well as to identify the cyst wall in order to fully resect the tumor with the cystic component to avoid recurrence and achieve better clinical results.

Ultrasound and MRI features of connatal cysts: clinicoradiological differentiation from other supratentorial periventricular cystic lesions

A 2-week-old neonate, born at 39 weeks via an uncomplicated vaginal delivery following a normal pregnancy, presented with a febrile illness suspected to be meningitis. A cranial ultrasound scan was performed (Figure 1). Figure 1 Coronal ultrasound image. As the patient had a persistent febrile illness, MRI was performed for investigation of suspected meningoencephalitis (Figure 2). Figure 2 Axial FLAIR (a) coronal T2-weighted (b) and coronal FLAIR (c) MR images performed to investigate suspected meningoencephalitis. What is your diagnosis?

蝶形骨洞に進展したクモ膜嚢胞例

Arachnoid cysts are commom intracranial lesions; however, their extension to the paranasal sinus is rare. Here we report a case of arachnoid cyst extending to the sphenoid sinus. Imaging examinations indicated an epidermoid cyst. We then performed endoscopic transsphenoidal surgery for partial resection of the cyst or formation of a drainage route. Opening the cyst wall resulted in a massive CSF leak, indicating an arachnoid cyst. Management of CSF leakage requires complete closure of the defect in the skull base using a fat graft and a pedicle mucosal flap elevated from the nasal septum. An arachnoid cyst should be included in the differential diagnosis of intracranial cystic lesions extending to the paranasal sinuses.

MR diffusion-weighted imaging in differential diagnosis of intracranial cystic lesions

目的 探讨MR扩散加权成像(DWI)在颅内囊性病变中的鉴别诊断价值.方法 对76例经临床及手术病理证实的颅内囊性病变患者,行常规MR、DWI及增强MR检查,其中脑脓肿19例,原发性脑胶质瘤20例,小脑血管母细胞瘤4例,脑转移瘤10例,蛛网膜囊肿7例,表皮样囊肿16例.回顾性分析颅内囊性病变的DWI信号特征,定量测定囊性变区表观扩散系数(ADC)值.结果 DWI上19例脑脓肿呈高信号;34例脑肿瘤患者中,除3例脑胶质瘤呈高信号、1例呈等信号,1例脑转移瘤呈高信号外,其余29例均呈低信号.各种病变ADC值分别为:脑脓肿(0.62±0.15)×10-3mm2/s、脑胶质瘤(2.39±0.78)×10-3mm2/s、脑血管母细胞瘤(2.68±0.40)×10-3mm2/s、脑转移瘤(2.79±0.79)×10-3mm2/s.脑脓肿与脑胶质瘤、脑血管母细胞瘤、脑转移瘤的囊变坏死区ADC值比较,差异均有统计学意义(P＜0.01);脑胶质瘤与脑血管母细胞瘤、脑转移瘤的囊变坏死区ADC值比较,差异均无统计学意义(P＞0.05).7例颅内蛛网膜囊肿的DWI呈低信号;16例表皮样囊肿DWI呈明显高信号.颅内蛛网膜囊肿和表皮样囊肿的ADC值分别为(2.96±0.36)×10-3mm2/s和(0.94±0.13)×10-3mm2/s,二者之间差异有统计学意义(P＜0.01).结论 DWI及ADC值对鉴别脑脓肿和囊性或坏死性脑肿瘤具有重要的价值,DWI表现为低信号的颅内囊性病变可除外脑脓肿。

Differential Diagnosis of Intracranial Cystic Lesions at Head US: Correlation with CT and MR Imaging

The differential diagnosis of intracranial cystic lesions at head ultrasonography (US) includes a broad spectrum of conditions: (a) normal variants, (b) developmental cystic lesions, (c) cysts due to perinatal injury, (d) vascular cystlike structures, (e) hemorrhagic cysts, and (f) infectious cysts. These lesions vary in prevalence from common (cavum of the septum pellucidum, subependymal cyst, choroid plexus cyst) to rare (vein of Galen malformation). US can provide important information about the anatomic location, size, and shape of the lesions as well as their mass effect on adjacent structures. Differential diagnosis may be difficult because there is substantial overlap of US features between many of these conditions. However, if careful attention is paid to the location and characteristics of the cyst, a more specific diagnosis may be suggested. Understanding the spectrum of appearances of the various intracranial cystic lesions at head US improves the diagnostic yield, enables one to understand their pathogenesis, and facilitates patient care.

Role of diffusion-weighted MR in differential diagnosis of intracranial cystic lesions

The purpose of this study was to evaluate the role of diffusion-weighted imaging (DWI) in characterizing cerebral cystic lesions. The usefulness of the apparent diffusion coefficient (ADC) map in lesion characterization was also evaluated. We compared the findings of conventional MR images with those of DWI: 63 cystic masses in 48 patients were examined with routine MR imaging and echo-planar DWI. The routine MR imaging included at least the axial T2- and T1-weighted sequences, and post-contrast T1 axial sequences. The DWI included an echo-planar spin-echo sequence with three values (0, 500 and 1000s/mm(2)) sensitizing gradient in the x, y, z direction, and it obtained an ADC map. The sensitivity of DWI for differentiating abscesses from primary brain tumours was 100%; for differentiating abscesses from metastatic tumours was 73%; for differentiating benign from malignant lesions was 90%. Although some metastatic lesions may appear hyperintense on DWI thus imitating an abscess, evaluation of the lesions with both DWI and conventional MRI may have an important contribution to the differentiation of tumours from abscesses.

Human chorionic gonadotrophin immunoactivity in cystic intracranial tumours

With regard to intracranial tumours, elevated hCG in CSF or serum has been considered to be specific for germ-cell tumours. Recently however, elevated hCG has also been shown to be present in cyst fluid and CSF of patients with craniopharyngiomas. While germ-cell tumours are generally non-cystic, the aim of our study was to determine the significance of hCG in cystic intracranial lesions. In a prospective study, hCG immunoactivity and subunits of hCG were measured in cyst fluid, CSF, and serum of patients harbouring intracranial cyst lesions. hCG immunoactivity was measured in cyst fluid and serum samples of 42 patients. CSF samples were available from 12 patients with craniopharyngiomas. In order to fully characterize the hCG immunoactivity, we used immunoradiometric assays for total hCG activity (measuring both intact hCG and the free beta-subunit of hCG), and those specific for intact, dimeric hCG (hCG), free beta-subunit of hCG (hCG beta) and free alpha-subunit. Furthermore, immunostaining of tumour tissue was performed using monoclonal antibodies directed against the free beta-subunit of hCG. Total hCG immunoactivity was markedly elevated in cyst fluid of all 17 craniopharyngiomas (range 36.7-4558 IU/I; normal < 5 IU/I). Moderately elevated levels of hCG in cyst fluid were detected in three of four pituitary adenomas, in two metastases from lung cancer and in two arachnoid cysts. hCG beta was detected in cyst fluid from all hCG positive cysts, while specific determination of intact (dimer) hCG and alpha-subunit mostly yielded negative results. No hCG immunoactivity was found in cystic gliomas, meningiomas or haemangioblastomas. hCG was elevated in CSF of two patients with craniopharyngiomas, but no hCG immunoactivity was detected in any serum sample. Subtle immunostaining of epithelial cell groups was shown in five of ten craniopharyngiomas. Clear immunostaining for hCG beta was also found in scattered epithelial cells of one pituitary adenoma. hCG immunoactivity in cystic intracranial lesions is due mainly to hCG beta. Measurement of hCG immunoactivity in cyst fluid can be helpful in the differential diagnosis of intracranial cystic lesions, if surgery is restricted to cyst decompression and no histology is available. High levels suggest a craniopharyngioma.

Cystic cavernous haemangiomas of the brain.

Two cases of cystic cavernous haemangioma of the brain are reported. In both cases, an erroneous diagnosis of cystic glioma was made, because of the unusual CT scan findings. Cavernous haemangiomas should be included in the differential diagnosis of intracranial cystic lesions.