Magnetic Resonance Angiography and Cisternography fused images in acute ischemic stroke may save time during endovascular procedure revealing vessel anatomy

Background and purpose

Endovascular treatment (EVT) is a time-dependent procedure that aims to remove the arterial blood flow obstruction in brain vessels in acute ischemic stroke. In our center, the MRI patient selection protocol in acute ischemic stroke is performed with DWI, FLAIR, MR angiography (MRA) and MR cisternography (MRC) sequences. MRA and MRC are promptly and automatically fused in order to have a clear detection of vessel anatomy, before and during EVT.

Our study aim is to evaluate if the fusion process between MRA and MRC could be considered time-safe and could influence EVT duration or outcome.

Materials and methods

45 patients were retrospectively selected for the study and divided into 2 groups according to the presence of MRC sequence fused with MRA (Group 1) or not (Group 2 - controls).

Results

MRA and MRC fusion was able to depict vessel anatomy in all subjects of Group 1 (22 patients, 12 females; age 75.59 years ± 10.87). Group 1 presented EVT time reduction (p < 0.05;p = 0.040) (51.59 min ± 30.94) when compared to Group 2 (23 patients, 13 females; age 75.04 years ± 12.12) (71.96 min ± 34.55) of 20.37 min average. No differences between groups were detected evaluating: NIHSS at admission (p = 0.49) and discharge (p = 0.67), pre-stroke mRS (p = 0.89), mRS at 90 days (p = 0.62), ASPECT (p = 0.98) and ASPECT-DWI scores (p = 0.93), time from symptom onset to groin puncture (p = 0.80), thromboaspiration vs combined technique (p = 0.67), EVT success (p = 0.63).

Conclusion

Fusion of MRA and MRC is a safe and promising technique in promptly revealing vascular anatomy beyond vessel obstruction, and can play a role in EVT duration reduction.

Imaging of the Spontaneous Low Cerebrospinal Fluid Pressure Headache: A Review

Spontaneous intracranial hypotension (SIH) is a significant cause of chronic, postural headaches. Spontaneous intracranial hypotension is generally believed to be associated with cerebrospinal fluid (CSF) leaks, and these leaks can be posttraumatic, iatrogenic, or idiopathic in origin. An integral part of the management of patients with this condition consists of localizing and stopping the leaks. Radiologists play a central role in the workup of this condition detecting leaks using computed tomography, magnetic resonance imaging, or nuclear imaging. In this article, we briefly review SIH and the various imaging modalities, which can be used to identify and localize a spontaneous CSF leak.

Intrasphenoidal Encephalocele with Spontaneous Cerebrospinal Fluid Rhinorrhea in Idiopathic Intracranial Hypertension: Need for Clarity in Terminology and Imaging Delineation

BACKGROUND

Magnetic resonance imaging plays an important role in identification of any underlying structural cause in spontaneous cerebrospinal fluid (CSF) leaks-either rhinorrhea or otorrhea. Sphenoid bone defects have been reported in those presenting as idiopathic intracranial hypertension with or without CSF rhinorrhea. Sphenoid lateral recess defect with intrasphenoidal encephalocele is one of the uncommon causes of spontaneous CSF leakage. Many classifications of basal encephaloceles have been used along with associated predisposing anatomic factors for the CSF leak.

CASE DESCRIPTION

We report 2 cases of spontaneous CSF rhinorrhea in 2 middle-aged females and had intrasphenoidal encephalocele on imaging using 3-dimensional magnetic resonance cisternography and computed tomography.

CONCLUSIONS

We discuss the various classification systems of sphenoidal encephaloceles and review the terminology and comprehensive imaging details to be included in reporting such cases for appropriate treatment planning.

[A case of chordoma presenting as recurrent bacterial meningitis with cerebrospinal fluid leakage]

A 52-year-old man was admitted to our hospital because of two episodes of bacterial meningitis within a 6-month period. CSF examination showed neutrophilic pleocytosis with marked elevation of protein and hypoglycorrhachia, but the inflammatory reaction was mild and blood and CSF cultures were negative. At the time of the second admission, intermittent watery nasal discharge caused by CSF rhinorrhea was evident. CT and MR imaging revealed a tiny clival bone defect, and transnasal endoscopic repair was performed successfully. The pathological diagnosis was chordoma based on immunohistochemical staining for brachyury. Although chordoma presenting as recurrent bacterial meningitis occurs extremely rare, asking patients detailed questions about the CSF rhinorrhea must be essential for disclosing unclear infection sources.

Analysis of Various Factors and Techniques to Improve Outcome of Surgical Management of 243 Cases of CSF Rhinorrhea

Cerebrospinal fluid (CSF) rhinorrhea occurs when there is a communication between subarachnoid space and sinonasal mucosa due to meningeal, osseous and mucosal defects in the cranial base leading to discharge of CSF from the nose. The risk of developing meningitis after CSF rhinorrhea may vary from 5.6 (Leech and Paterson in Lancet 1:1013-1016, 1973) to 60% (Eljarnel and Foy in Br J Neurosurg 5:275-279, 1991). Hence surgical management of CSF rhinorrhea is highly recommended. Transnasal endoscopic approach first described by Wigand in 1981, has been proven to be the approach of choice in comparison to intracranial and external nasal approach (Jones and Becker in Br Med J 322:122-123, 2001) in most cases. The next defining milestone was the pedicled naso septal vascularized flap described by Hadad et al. (Laryngoscope 116(10):1882-1886, 2006), which could be used to manage large defects. In the present study we assessed 243 cases of CSF rhinorrhea managed by transnasal endoscopic approach. We compared the various factors associated with CSF rhinorrhea and the correlation with the outcome of the surgical treatment. We also analyzed the different sites and techniques of surgical repair and have certain recommendations to improve the surgical outcome. The commonest cause of CSF leak was spontaneous (54.32%) and the commonest site was cribriform plate (43.24%). Patients presented most commonly with watery nasal discharge (82.3%). CT scan with cisternography or MR cisternography is the gold standard to identify the suspected site of leak. Out of 243 patients, 77.77% were operated using free grafts and 22.22% by flap repair. Results are comparable. Hence we would advise simple conservative technique with free grafts to reduce morbidity and shorten the postoperative recovery.

Phase-contrast MRI and 3D-CISS versus contrast-enhanced MR cisternography for the detection of spontaneous third ventriculostomy

PURPOSE

To compare the diagnostic efficacies of phase-contrast MRI (PC-MRI) and three-dimensional constructive interference in steady-state (3D-CISS) sequence for the detection of spontaneous third ventriculostomy (STV) on the basis of contrast-enhanced MR cisternography (MRC).

PATIENTS AND METHODS

Eleven obstructive hydrocephalus patients with clinically-radiologically suspected STV and ten controls were examined by PC-MRI, 3D-CISS and MRC. PC-MRI and 3D-CISS sequence were applied to view the third ventricle and basal cisterns. Following injection of 0.5-1ml intrathecal Gd-DTPA injection, postcontrast MRC images were obtained in three planes. Presence of STV was scored as follows: grade 0, no existence of STV; grade 1, STV present. Results of PC-MRI and 3D-CISS were compared with the MRC findings.

RESULTS

In PC-MRI, five patients were assessed as grade 0 and six cases grade 1. As a result of 3D-CISS sequence, eight cases were evaluated as grade 0 and three cases grade 1. Based on MRC, nine cases were assessed as grade 0 and two cases grade 1. False positivity was found in four cases by PC-MRI and in one case by 3D-CISS. The sensitivity, specificity and accuracy of PC-MRI and 3D-CISS sequence regarding demonstration of STV, were 100, 100, 56, 89, 64, and 91% respectively.

DISCUSSION

PC-MRI and 3D-CISS are helpful in confirming the STV. PC-MRI and 3D-CISS should be the first preference. If PC-MRI and 3D-CISS give negative results, then MRC is not required. MRC should be performed on patients who demonstrate suspected STV findings on PC-MRI and 3D-CISS sequences. MRC may prevent false positive results.