Cervical CT-guided, selective nerve root blocks: improved safety by dorsal approach

Cervical transforaminal blocks are frequently performed as a treatment of cervical radicular pain. These blocks are performed mostly under fluoroscopy, but a CT-guided technique also has been described. We describe a modification that leads to a more extraforaminal than transforaminal and equally selective nerve root block.     

Traumatic lumbosacral nerve root avulsion: evaluation by MR imaging

Magnetic resonance (MR) imaging of traumatic lumbosacral nerve root avulsion and pseudomeningocele formation at multiple nerve root levels is presented. We report a case of this rare clinicopathologic entity identified by MR imaging in conjunction with more traditional lumbar myelography.     

Lumbosacral nerve root avulsions: MR imaging demonstration of acute abnormalities

Most of the previously reported lumbosacral nerve root avulsions presented with pseudomeningoceles at the time of delayed initial imaging. We report a case of traumatic lumbosacral nerve root injury associated with an isolated femur fracture and demonstrate the evolution of pseudomeningoceles following nerve root avulsions and edema in the perineural fat identified on the initial MR imaging.     

Selective nerve root blocks

Selective nerve root blocks are an effective way of diagnosing and treating radicular pain in many patients. Although traditionally performed under fluoroscopic guidance, computed tomography (CT) and CT fluoroscopy have been increasingly used to direct needle placement. This article discusses the indications and technique of selective nerve root blocks in the cervical, thoracic, and lumbar spine, as well as the evidence supporting their use in the treatment of patients with radiculopathy and/or back pain. Copyright 2002, Elsevier Science (USA). All rights reserved.     

Selective nerve root blocks

Selective nerve root blocks are valuable diagnostic and therapeutic procedures in patients with radicular symptoms. Understanding the anatomy, benefits, and risks, as well as precise needle placement, are important factors in performing successful nerve root blocks. The techniques we describe come from our training and ongoing experience. There are other acceptable methods as well.     

CT fluoroscopic-guided cervical nerve root blocks

While both fluoroscopic and CT-guidance during cervical nerve root blocks have been well documented in the literature, the use of CT fluoroscopy (CTF) has not. CTF is well suited to provide imaging guidance during these procedures due to its combination of excellent anatomic detail, relatively low radiation dose and the ability to perform an initial dynamic contrast injection, and is a viable alternative to fluoroscopic guidance. Details of the technique along with the initial experience at one institution are presented.     

Cervical esophageal duplication cyst: MR imaging

Magnetic resonance (MR) imaging was performed in the evaluation of a cervical esophageal duplication cyst in a 9-month-old infant. The value of MR in the assessment of the origin of this cystic lesion as well as the nature of its contents is discussed.     

Facial nerve neuromas: MR imaging

Summary Four cases of facial nerve neuroma were evaluated by computed tomographic (CT) scan and magnetic resonance imaging (MRI). The extension of the tumor in the petrous bone or the parotid gland was well defined by MRI in all cases. CT scan was useful to demonstrate bone erosions and the relation of the tumor to inner ear structures. In cases of progressive facial palsy, CT and MRI should be combined to detect a facial neuroma and to plan the surgical approach for tumor removal and nerve grafting.     

MEDIC序列在MR腰骶脊神经根成像中的临床应用

目的探讨Siemens 3T磁共振多回波数据图像重合(multiecho data image combination,MEDIC)序列在腰骶脊神经根显示的技术及病变诊断的应用价值。方法用Siemens 3TVerio磁共振成像仪,对35例腰痛患者行腰椎MRI常规序列(矢状位T1W,T2W,横轴位T2W)、冠状位MEDIC序列及MR脊髓造影MRM序列扫描,MEDIC序列及MRM序列的所有图像均用3D最大信号强度投影(MIP)后处理。由2位高级职称MRI影像诊断医师对MIP重建后图像所显示的腰骶脊神经根长度、形态及病变的影像表现,评价MEDIC序列的应用价值。结果 MEDIC序列显示腰骶脊神经根长度达节后段,MRM未显示节后段。MEDIC序列用MIP软件行神经根曲面容积重建能清晰显示神经根鞘受压移位、神经根病变及与神经根关系的全貌。结论 MEDIC序列能诊断神经根病变,且图像质量优于MRM,是常规MRI的重要补充;用MIP软件行神经根曲面容积重建图像可提供直观的解剖形态信息。     

Cervical radiculopathy: value of oblique MR imaging

Eighteen patients with cervical radiculopathy were entered into a prospective study to compare the accuracy of surface coil magnetic resonance (MR) imaging with that of metrizamide myelography and computed tomography (CT) with metrizamide. All MR studies included tailored axial and oblique images as well as routine sagittal images. All imaging studies were evaluated for topography and type of disease. Nine of 18 patients subsequently underwent cervical surgery with an anterior interbody approach at 11 levels. The surface coil MR findings concerning disease topography and type concurred with the surgical findings at nine of 11 levels (82%). At three levels, the oblique view added important information not available on the sagittal images or clarified changes seen on the axial images. Metrizamide myelography with CT metrizamide myelography had findings concurrent with surgical findings at ten of 11 levels (91%).     

Cervical MR imaging in postural headache: MR signs and pathophysiological implications

BACKGROUND AND PURPOSE: Postural headache most often occurs after lumbar puncture as post-lumbar puncture headache (PLPH) or, rarely, spontaneously as spontaneous intracranial hypotension headache (SIHH). In this prospective study, we used spinal MR imaging to determine the findings that would assist in the diagnosis of PLPH and SIHH and that would further our pathophysiological understanding of postural headache. METHODS: The study group consisted of 15 healthy volunteers and 20 patients with postural headache: nine with SIHH and 11 with PLPH. The craniocervical junction and the cervical spine were studied using T2-weighted fast spin-echo and T1-weighted spin-echo sequences in the axial and sagittal planes. Follow-up studies were performed in 13 patients. RESULTS: Dilatation of the anterior internal vertebral venous plexus was the most constant finding, present in 17 (85%) of 20 patients with postural headache. Spinal hygromas, whose location as subdural or epidural could not be exactly determined, were present in 14 patients (70%). A focal fluid collection was detected in the retrospinal region at the C1-C2 level in six patients with SIHH and in four patients with PLPH (50%). Tonsillar descent was detected in only one patient, and subtentorial hygroma in five patients. No abnormalities were found in the volunteers. CONCLUSION: The MR signs of dilatation of the venous plexus, presence of spinal hygromas, and presence of retrospinal fluid collections can help to establish the diagnosis of intracranial hypotension. They are probably the result of decreased CSF volume, with the retrospinal fluid collections being a transudate from the venous plexus rather than frank extravasation. Resolution of these signs parallels resolution of the headache.     

Clinical evaluation of lumbosacral nerve root and lateral stenosis using coronal MR imaging]

MR imaging is being used more frequently to study the lumbar spine and is becoming the modality of choice in the assessment of patient with low back pain. Using a new technique of coronal and half coronal scan with MR imaging, it was possible to visualize L4, L5 and S1 nerve roots accurately. We described the MR findings of lateral stenosis using this technique. Several characteristic MR findings were identified, and the most important one was nerve root impingement in the intervertebral foramen. We consider that coronal and half coronal scan with MR imaging is useful in diagnosis of lateral stenosis.     

Cervical neural foramina: correlative anatomic and MR imaging study

Accurate diagnosis of diseases affecting the cervical neural foramina with magnetic resonance (MR) imaging requires an appreciation of the normal anatomic appearance of the foramen. The MR appearance of the foramen was studied in cadavers and healthy volunteers and was correlated with cadaver cryomicrotome sections. With gradient-echo techniques, foraminal soft tissues are highlighted relative to adjacent bone, making gradient-echo images valuable for evaluating the overall size and contents of the neural foramina. Intravenously administered gadolinium DTPA produces enhancement of all foraminal soft tissues, including the dorsal root ganglion. The nerve roots do not enhance with Gd-DTPA. Gradient-echo pulse sequences and intravenous use of Gd-DTPA represent promising techniques for the evaluation of the cervical foramina.     

Neuroblastoma: the role of MR imaging

Thirty-five MR examinations were performed in 17 children with neuroblastoma during the course of their diagnostic evaluation and treatment. Findings were confirmed by correlation with the results of other imaging techniques, biopsies, and surgical and autopsy findings. MR accurately detected the lesions and their extent in all patients. It correctly evaluated the possibility of resectability and showed metastases, response to treatment and development of complications. MR appears to be a reliable technique for the diagnosis, staging, and follow-up of children with neuroblastoma.     

Trigeminal nerve: anatomic correlation with MR imaging

Through correlation with cryomicrotic sections, the appearance of the trigeminal nerve and its branches on magnetic resonance images is described in healthy individuals and in patients with tumors involving this nerve. Coronal images are best for defining the different parts of the nerve and for making a side-to-side comparison. Sagittal images are useful to demonstrate tumors involving the gasserian ganglion.