OBJECTIVESTo reveal the relationship of brain motion and cerebrospinal fluid (CSF) flow by phase-contrast cine MRI, and to evaluate this technique in differentiating between arachnoid cysts and subarachnoid space enlargement.

METHODSUsing a phase-contrast cine MRI pulse sequence, we measured brain motion and CSF flow during the cardiac cycle in 10 healthy volunteers and 10 patients with MRI-suspected arachnoid cyst or subarachnoid space enlargement. CSF stroke volume curve was illustrated according to flow quantification, and time-signal intensity curve was traced. The two curves were compared.

RESULTSThis study showed that brain motion was due to the volume difference between arterial and venous blood flow during a cardiac cycle, and thus drives CSF pulsation. Arachnoid cysts and subarachnoid space enlargement carried different curve patterns, demonstrating that phase-contrast MRI and flow quantification can be a useful and reliable technique for non-invasive evaluation of brain motion and CSF flow.

CONCLUSIONArachnoid cysts can be successfully differentiated using phase-contrast cine MRI from subarachnoid space enlargement.

Adult ; Arachnoid Cysts ; diagnosis ; Diagnosis, Differential ; Female ; Humans ; Magnetic Resonance Imaging, Cine ; Male ; Subarachnoid Space ; pathology

Intracranial lesions may show contrast enhancement through various mechanisms that are closely associated with the disease process. The preferred magnetic resonance sequence in contrast imaging is T1-weighted imaging (T1WI) at most institutions. However, lesion enhancement is occasionally inconspicuous on T1WI. Although fluid-attenuated inversion recovery (FLAIR) sequences are commonly considered as T2-weighted imaging with dark cerebrospinal fluid, they also show mild T1-weighted contrast, which is responsible for the contrast enhancement. For several years, FLAIR imaging has been successfully incorporated as a routine sequence at our institution for contrast-enhanced (CE) brain imaging in detecting various intracranial diseases. In this pictorial essay, we describe and illustrate the diagnostic importance of CE-FLAIR imaging in various intracranial pathologic conditions.
Arachnoid Cysts/*diagnosis/pathology ; Brain/*pathology ; Brain Neoplasms/*diagnosis/pathology ; Contrast Media ; Humans ; Magnetic Resonance Imaging/*methods

STUDY DESIGN: Retrospective case–control study PURPOSE: To clarify the prevalence and risk factors for spinal subdural lesions (SSDLs) following lumbar spine surgery. OVERVIEW OF LITERATURE: Because SSDLs, including arachnoid cyst and subdural hematoma, that develop following spinal surgery are seldom symptomatic and require reoperation, there are few reports on these pathologies. No study has addressed the prevalence and risk factors for SSDLs following lumbar spine surgery. METHODS: We conducted a retrospective analysis of the magnetic resonance (MR) images and medical records of 410 patients who underwent lumbar decompression surgery with or without instrumented fusion for degenerative disorders. SSDLs were classified into three grades: grade 0, no obvious lesion; grade 1, cystic lesion; and grade 2, lesions other than a cyst. Grading was based on the examination of preoperative and postoperative MR images. The prevalence of SSDLs per grade was calculated and risk factors were evaluated using multivariate logistic regression analysis. RESULTS: Postoperative SSDLs were identified in 123 patients (30.0%), with 50 (12.2%) and 73 (17.8%) patients being classified with grade 1 and 2 SSDLs, respectively. Among these, one patient was symptomatic, requiring hematoma evacuation because of the development of incomplete paraplegia. Bilateral partial laminectomy was a significantly independent risk factor for SSDLs (odds ratio, 1.52; 95% confidence interval, 1.20–1.92; p<0.001). In contrast, a unilateral partial laminectomy was a protective factor (odds ratio, 0.11; 95% confidence interval, 0.03–0.46; p=0.002). CONCLUSIONS: The prevalence rate of grade 1 SSDLs was 30%, with no associated clinical symptoms observed in all but one patient. Bilateral partial laminectomy increases the risk for SSDLs, whereas unilateral partial laminectomy is a protective factor.
Arachnoid ; Arachnoid Cysts ; Decompression ; Hematoma ; Hematoma, Subdural ; Hematoma, Subdural, Spinal ; Humans ; Laminectomy ; Logistic Models ; Medical Records ; Paraplegia ; Pathology ; Prevalence* ; Protective Factors ; Reoperation ; Retrospective Studies ; Risk Factors* ; Spine*

Sellar arachnoid cysts are rare; an infected arachnoid cyst is extremely rare as only one case has been reported to date in the literature. Here, we report a patient with an infected or inflamed sellar arachnoid cyst that was successfully treated with transsphenoidal surgery (TSA). A 53-year-old female with a history of chronic sinusitis developed a headache 5 months ago, and one month before admission polyuria, polydipsia, and abnormal vaginal bleeding occurred. The magnetic resonance imaging (MRI) showed a sellar cystic mass with a thickened pituitary stalk. Preoperative hormonal study revealed normal pituitary hormone levels except for a moderate elevation of prolactin. She was diagnosed with diabetes insipidus of the central nervous system origin based on a water-deprivation test. TSA was performed under an impression of symptomatic Rathke's cleft cyst according to the MRI findings. Intraoperative findings showed confirmation of turbid intracystic contents, but micro-organisms were unidentified on microbial culture. Pathology of the cyst wall revealed inflamed meningoepithelial lining cells compatible with an arachnoid cyst.
Arachnoid Cysts ; Arachnoid* ; Central Nervous System ; Diabetes Insipidus ; Female ; Headache ; Humans ; Inflammation ; Magnetic Resonance Imaging ; Middle Aged ; Pathology ; Pituitary Gland ; Polydipsia ; Polyuria ; Prolactin ; Sinusitis ; Uterine Hemorrhage

OBJECTIVETo evaluate curative effect of the fibrinogen gel for treating sacral canal arachnoid cyst.

METHODSNineteen patients with sacral canal arachnoid cysts included 7 males and 12 females; The average age was 48.4 years ranging from 19 to 68 years. The course was from 2 weeks to 7 months. Of all the patients, 9 were in level of S1, 4 were in level of S1 to S2, 5 were in level of S2, 1 was in level of S1 to S3. Cystis wall greater partial excision adopted in 11 cases, partial resection in 8, then all patients were treated by spray painting fibrinogen gel.

RESULTSNineteen patients were followed-up for 13 to 30 months (mean 21.3 months). The clinical symptom disappeared completely in 18 patients, and only one patient urinated incapably, but after 2 weeks returned to normal. No one found recurrence by MRI after 12 months.

CONCLUSIONThis method of fibrinogen gel for treating sacral canal arachnoid cyst has advantages of easy performing, safety, achieve good results, less neck symptoms and early commencing of mobilization.

Adult ; Aged ; Arachnoid Cysts ; pathology ; therapy ; Female ; Fibrinogen ; administration & dosage ; Gels ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Sacrum

Oculomotor cistern is normal anatomic structure that is like an arachnoid-lined cerebrospinal fluid-filled sleeve, containing oculomotor nerve. We report a case of arachnoid cyst in oculomotor cistern, manifesting as oculomotor nerve palsy. The oblique sagittal MRI, parallel to the oculomotor nerve, showed well-defined and enlarged subarachnoid spaces along the course of oculomotor nerve. Simple fenestration was done with immediate regression of symptom. When a disease develops in oculomotor cistern, precise evaluation with proper MRI sequence should be performed to rule out tumorous condition and prevent injury of the oculomotor nerve.
Adult ; Arachnoid Cysts/*diagnosis/surgery ; Female ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Neurosurgical Procedures ; Oculomotor Nerve/*pathology ; Oculomotor Nerve Diseases/*diagnosis/surgery

Aicardi syndrome is a severe congenital disorder characterized by infantile spasms, chorioretinal lacunae, and agenesis or hypogenesis of the corpus callosum. A 6 month old female had developed abnormal eye movement and seizures of the complex partial type and myoclonic type. MRI pictures of the patient revealed the presence of genu associated with agenesis of the rest of corpus callosum. A funduscopic examination revealed bilateral small, solitary, pale areas with sharp borders, some of which had minimal surrounding pigmentation (chorioretinal lacunae), especially clustered around the disc, and they were more prominent on the left side. We report here on the unusual findings of a complex partial seizure, myoclonic seizure and the atypical EEG finding in addition to the well-known characteristic clinical and imaging findings of a patient with Aicardi syndrome.
Anticonvulsants/therapeutic use ; Arachnoid Cysts/*pathology ; Corpus Callosum/*abnormalities ; Electroencephalography ; Epilepsies, Myoclonic/drug therapy/*pathology ; Epilepsies, Partial/drug therapy/*pathology ; Female ; Humans ; Infant ; Magnetic Resonance Imaging ; Retinal Diseases/*pathology ; Spasms, Infantile/drug therapy/*pathology ; Syndrome

Neurocutaneous melanosis (NCM) is a rare congenital disease that is characterized by the presence of large or multiple congenital melanocytic nevi and melanotic lesions of the central nervous system. We report here on the CT and MR imaging findings of an unusual case of NCM that was associated with intraventricular dermoid and Dandy-Walker malformation.
Tomography, X-Ray Computed ; Neurocutaneous Syndromes/*epidemiology/radiography ; Melanosis/*epidemiology/radiography ; Male ; Magnetic Resonance Imaging ; Humans ; Dermoid Cyst/*epidemiology/radiography ; Dandy-Walker Syndrome/*epidemiology ; Comorbidity ; Cerebral Ventricle Neoplasms/*epidemiology/radiography ; Arachnoid Cysts/epidemiology/pathology ; Adult