Cerebrospinal fluid rhinorrhea: evaluation with metrizamide cisternography

Metrizamide computed tomographic cisternography was used to examine 27 patients (19 males and eight females, 14-59 years old) clinically suspected of having cerebrospinal fluid fistulae with rhinorrhea. Twenty-one fistulae were traumatic and six were spontaneous. Five to 6 ml of metrizamide (or lopamidol, two cases) were injected by lumbar puncture at a concentration of 185-200 mg I/ml for direct coronal and axial computed tomographic sections of the skull base. Cerebrospinal fluid rhinorrhea was present at the time of examination in 12 of 27 cases. Results were evaluated according to three criteria: (1) metrizamide passage through the bony and dural defect; (2) demonstrable site of the fracture and/or bony defect; and (3) metrizamide visualized within a paranasal sinus, nasal cavity, or cotton pledget. The examination was considered positive when criterion 1 alone was present and when 2 and 3 were associated. In 15 of 27 cases, cisternography was positive, with the exact site of cerebrospinal fluid leakage demonstrated in 10 patients. In six cases, the results were not definitive; only one of the criteria (2 or 3) was fulfilled. In six cases, cisternography was normal. Seventeen patients underwent surgery. The site of cerebrospinal fistulae was ethmoidal in nine cases, frontoethmoidal in seven, sphenoidal in two, and sphenoethmoidal in one. The relative value of metrizamide computed tomographic cisternography compared with other diagnostic studies, polytomography, positive or negative contrast studies, and radionuclides, is discussed. Diagnostic pitfalls include artifacts and partial volume effect.     

Cerebrospinal fluid rhinorrhea: Diagnostic role of gadolinium enhanced MR cisternography

Background

Accurate localization of the defect is crucial for successful surgical repair of CSF rhinorrhea. This could be achieved by MRI cisternography using T1 weighted sequences followed by intra-thecal injection of low dose of gadolinium for valuable localization and characterization of the defect.

Aim

The aim of this study was to evaluate the role of intrathecal gadolinium enhanced MR cisternography in localization of the defect in cases of CSF rhinorrhea to demonstrate how to utilize it as a roadmap to select the most appropriate approach for leak repair.

Patients and methods

This study included 24 patients (16 male and 8 females) with CSF rhinorrhea, referred from Otorhinolaryngology Department. Seventeen leaks were spontaneous, 5 cases were traumatic and two iatrogenic. All cases underwent MR gadolinium enhanced cisternography via lumbar puncture.

Results

Gadolinium enhanced MR cisternography accurately diagnosed and confirmed the site of CSF leak in 22/24 (91.7%) cases. The most common site was the ethmoidal roof in 18/24 cases. Our results were correlated with endoscopic surgery and repair with an accuracy rate of 100%.

Conclusions

Intra-thecal gadolinium enhanced MR cisternography is essential for accurate pre-operative localization and characterization of the defect in cases of CSF rhinorrhea.     

Cerebrospinal fluid fistula: detection with MR cisternography.

PURPOSEOur goal was to assess the role of MR cisternography in the examination of patients with suspected CSF rhinorrhea.METHODSMR cisternography was performed as a heavily T2-weighted fast spin-echo study with fat suppression and video reversal of the images in 37 patients over a 3-year interval. Twenty-four of the patients subsequently had exploratory surgery for fistula. Statistical analysis of the surgical results was compared with the findings at MR cisternography.RESULTSMR cisternography showed significant correlation with surgical findings, with sensitivity, specificity, and accuracy of 0.87, 0.57, and 0.78, respectively.CONCLUSIONMR cisternography proved to be an accurate diagnostic imaging technique in the evaluation of suspected CSF rhinorrhea.     

CT cisternography in evaluation of cerebrospinal fluid rhinorrhea

Summary The clinical, radiological and surgical features of 14 patients who presented with cerebrospinal fluid rhinorrhea and had undergone surgical treatment during a three-year period are given with special reference to pre-operative evaluation by CT cisternography. The merits and demerits of this technique are discussed.     

Controlled overpressure cisternography to localize cerebrospinal fluid rhinorrhea

Cerebrospinal fluid (CSF) rhinorrhea is often intermittent, thus complicating the cisternographic localization of the leakage. In four patients studied, this difficulty was overcome by lumbar infusion of artificial CSF to which a bolus of radionuclide was added. The tracer was moved in bulk to the basal cisterns, and the rise in CSF pressure elicited a profuse rhinorrhea. Sequential imaging was started during the infusion, and prompt identification of the site of leakage was easily obtained. Special precautions must be followed when this technique of overpressure is used.     

MR脑池造影术在诊断脑脊液鼻漏中的价值

目的研究MR脑池造影术（MRC）显示脑脊液鼻漏的能力，并比较分析高分辨率CT（HRCT）、CT脑池造影术（CTC）和MRC显示脑脊液鼻漏的优缺点。方法18例怀疑脑脊液鼻漏的患者分别行HRCT和MRC，同时10例成功进行CTC，对照手术结果比较分析3种方法显示脑脊液鼻漏的准确性。结果18例患者手术共发现29个瘘口；18例患者术前HRCT显示25个瘘口，与手术相符的瘘口数为18个（18／29）；18例患者术前MRC显示24个瘘口，与手术相符的瘘口数为21个（21／29）。10例患者术前CTC显示12个瘘口，手术共发现18个瘘口，与手术相符的瘘口数为11个（11／18），手术发现而CTC未显示的瘘口数为7个。经统计学分析，三种方法显示脑脊液瘘口的差异无统计学意义（P〉0．05）。结论HRCT和MRC都是无损伤性的、简单易行的检查方法，二者结合起来可较准确地显示脑脊液鼻漏及其瘘口，可取代有损伤性的、费时的CTC。     

Cerebrospinal fluid imaging using serial metrizamide CT cisternography

Summary Twenty-five patients studied by serial metrizamide (Amipaque) CT cisternography were used to analyze CSF kinetics. Delayed CSF flow patterns were noted in 7 patients, while intermediate patterns occurred in 4. The abnormal cisternogram was characterized primarily by ventricular reflux and stasis and secondarily by diminution of the parasagittal blush and a periventricular rim of decreased absorption. The intermediate group had minimal ventricular stasis after 24 hours and a normal parasagittal blush. After clinical and biochemical evaluation of the patient with dementia, CT scanning is usually indicated. If a profile suggestive of communicating hydrocephalus emerges, CSF kinetics can be monitored dynamically by CT scanning with metrizamide enhancement.     

Cerebrospinal fluid shunts: flow measurements with MR imaging

The authors describe a technique for determination of shunt patency by quantifying cerebrospinal fluid shunt flow rates with magnetic resonance (MR) imaging. This method uses a modified clinical sequence that is both sensitive to slow flow perpendicular to the imaging plane and capable of achieving oblique angles with a 4-cm field of view. Velocity-dependent phase images were used to quantify flow rates within the shunt. A preliminary study was performed in seven patients with hydrocephalus and cerebrospinal fluid shunts. Two patients were found to have zero flow in the shunt, while the remaining five had flow rates ranging from 4 to 19 mL/h. Results showed that the measurement of flow rates within the shunt lumen with MR imaging is clinically feasible.     

Cerebrospinal fluid pulsation: benefits and pitfalls in MR imaging

Physiologic cerebrospinal fluid (CSF) pulsation causes a harmonic modulation of proton precessional phase with two-dimensional Fourier transform (2DFT) imaging, which results in predictable regions of signal loss and the presence of phase-shift images ("ghost images"). CSF that is not pulsating exhibits a higher signal than does pulsatile CSF. This phenomenon can be diagnostically useful in disease entities associated with decreased CSF pulsation amplitude, such as arachnoid cyst, intraventricular cyst, spinal stenosis, and spinal block caused by extramedullary or epidural tumor. Unfortunately, this increased signal can also mimic disease such as epidural tumor in the spine or acoustic neuroma in the internal auditory canal. An abnormal pattern of CSF pulsation, as occurs in patients with arachnoiditis, can cause unusual areas of signal loss, which complicate image interpretation and can mimic pathologic conditions. Recognition of CSF pulsation effects will increase in importance as thin-section magnetic resonance imaging becomes more common, because thin sections enhance these effects with 2DFT.     

The diagnosis of CSF fistulas with rhinorrhea by isotope cisternography

Summary The experience with the use of RIHSA cisternography in cases of spontaneous or post-traumatic CSF rhinorrhea is reported. The utility of this method for identifying the fistulous tract so that the neurosurgeon can, as far as he is able, carry out a direct and not solely exploratory operation is pointed out.     

Cerebrospinal fluid: detection of tumors and disk herniations with MR spectroscopy

Cerebrospinal fluid (CSF) samples from 84 patients with confirmed or suspected diseases of the central nervous system were studied with hydrogen-1 magnetic resonance (MR) spectroscopy. In 19 of the patients, clinical chemical tests of the CSF indicated normal protein contents and normal quantities of cells; these samples were used as controls. Preliminary results indicate that tumors may be reflected in the MR spectra of CSF; disk herniations could not be distinguished on the basis of the MR spectral characteristics.     

Cerebrospinal fluid flow in patients with dilated ventricles studied with MR imaging

The purpose of this study was to measure the cerebrospinal fluid (CSF) velocity and flow in the aqueduct in patients with wide ventricles with or without signs of normal pressure hydrocephalus (NPH) before and after shunt surgery. We studied 18 patients with wide ventricles with MRI and measured the CSF velocity values in the aqueducts. Twelve patients with the clinical triad of NPH were examined. Six patients were studied only before shunt surgery and 6 patients were studied both before and after shunt surgery. Three patients with wide ventricles without clinical triad of NPH, and 3 patients with hydrocephalus following subarachnoid hemorrhage were also examined. Seven NPH patients with hyperdynamic CSF flow and three NPH patients with normal CSF velocity and flow values showed a positive clinical response to shunt surgery. Two of the three patients with hydrocephalus and hyperdynamic CSF flow values in the aqueduct secondary to subarachnoid bleeding responded to shunt surgery. One patient with same disease and low CSF velocity and flow values did not respond. No change was detected in the CSF flow values of the aqueduct when measurements before and after shunt surgery were compared. Ventriculoperitoneal shunting does not change the CSF dynamics in the aqueduct. Received: 8 March 1999; Revised: 30 November 1999; Accepted: 23 February 2000     

CSF rhinorrhea: detection and localization using overpressure cisternography with Tc-99m-DTPA

We performed 32 overpressure radionuclide cisternography (ORNC) studies to examine 26 patients who were clinically suspected of having cerebrospinal fluid (CSF) fistula with rhinorrhea. Fifteen (47%) of these cisternography studies were positive, and the site of the leak was identified. No leak could be demonstrated in the other 17. Of 23 examinations performed in patients who had clinically documented CSF rhinorrhea, 15 (65%) were scintigraphically positive. The rapid cephalad transit of the radionuclide bolus allowed completion of the study within 30 to 45 minutes. Seven examinations were also performed with overpressure metrizamide CT cisternography (OMCTC), and five demonstrated concordant results with the radionuclide study. Patient discomfort and side effects were minimal. We conclude that radionuclide infusion cisternography is a safe, rapid, and accurate method of investigating a suspected or proven CSF rhinorrhea and that it is complementary to metrizamide cisternography.     

Cerebrospinal fluid flow waveforms: MR analysis in chronic adult hydrocephalus

Henry-Feugeas MC, Idy-Peretti I, Baledent O, et al. Cerebrospinal fluid flow waveforms: MR analysis in chronic adult hydrocephalus. Invest Radiol 2001;36:146-154.RATIONALE AND OBJECTIVES: To analyze changes in cerebrospinal fluid (CSF) hydrodynamics in chronic adult hydrocephalus. METHODS: Phase-contrast cine-MR acquisitions were used to explore the ventricular system and the upper ventral cervical spaces of 16 patients. The aqueductal jet was explored in 32 control subjects. RESULTS: The duration of pulsatile caudal CSF flow (ie, CSF systole) was abnormally short in patients with active idiopathic and obstructive hydrocephalus. The duration of CSF cervical systole was normal in patients with stable hydrocephalus. The aqueductal stroke volume could be increased in stable communicating hydrocephalus. Patients who responded to shunting had shortened CSF systoles and hyperpulsatile ventricular patterns. Successful CSF diversion resulted in longer CSF systoles and CSF ventricular patterns that were no longer hyperpulsatile. CONCLUSIONS: Magnetic resonance analysis of CSF flow can show craniospinal dissociation and limitation of CSF outflow from the ventricles in both obstructive and communicating hydrocephalus; it should help determine the response to shunting in communicating hydrocephalus.