[Cerebral and spinal cavernomas]. / Zerebrale und spinale Kavernome.

CLINICAL/METHODICAL ISSUE: Cavernous malformations or cavernomas belong to the angiodysplasias. They may be sporadic or familial and cause symptoms (epilepsy) despite the absence of a left-to-right shunt. In addition to intracranial locations, spinal cavernomas are also found. STANDARD RADIOLOGICAL METHODS: Magnetic resonance imaging (MRI) and computed tomography (CT) are used for diagnosis PERFORMANCE: MRI, except for acutely or subacutely hemorrhaged cavernomas, is superior to CT for lesion detection. ACHIEVEMENTS: CT is reserved for acute diagnosis. MRI, especially susceptibility-sensitive gradient echo sequences, can also detect cavernomas without (sub-)acute hemorrhage or calcifications. PRACTICAL RECOMMENDATIONS: MRI is also useful for differentiating the familial form vs. sporadic form. Digital subtraction angiography (DSA) is used for differential diagnosis in rare cases, as cavernomas show no correlate here.

[Spondylodiscitis and epidural abscesses]. / Spondylodiszitis und epiduraler Abszess.

CLINICAL/METHODOLOGICAL PROBLEM: Spondylodiscitis is an inflammation of the intervertebral disc, which in adults is generally associated with spondylitis of the adjacent vertebrae. It often presents clinically with nonspecific symptoms such as back or neck pain. It may be caused by various pathogens, especially bacteria. One or more vertebral segments can be affected. The infection can spread to surrounding compartments and can lead to epidural abscesses. Radiology, in particular magnetic resonance imaging (MRI), plays an important role in the diagnostic work-up and in the follow-up to monitor response to therapy. Treatment consists of conservative (antibiotics) and invasive approaches, including surgery. Interventional puncture and drainage is a promising alternative to surgery, especially in early stages of abscess formation. STANDARD RADIOLOGICAL METHODS: Magnetic resonance imaging (MRI), computed tomography (CT), nuclear medical procedures, conventional x­ray. PERFORMANCE: MRI has the highest value. CT and nuclear medical procedures can be used as a supplement to MRI and in patients with contraindications for MRI. PRACTICAL RECOMMENDATIONS: With adequate diagnosis and therapy, spondylodiscitis has a good prognosis. In addition to targeted or calculated drug therapy, invasive treatment is the main focus, especially for epidural abscesses. Interventional radiological drainage can represent a less invasive alternative to surgical treatment.

[Degenerative intervertebral disc processes : Current aspects of diagnosis]. / Degenerative Bandscheibenprozesse : Aktuelles zur Befundung.

Starting with the smallest functional unit, the spinal segment including the centrally located intervertebral disc, the spine and pelvis including the sacroiliac and hip joints form a functional unit. The discs play an important role in the complex interaction between disc, osseous and ligamentous structures and the adjacent muscles. Disc pathologies are very frequently associated with changes of the adjacent endplates of the vertebral bodies and can be depicted at an early stage using magnetic resonance imaging (MRI). The focus of the diagnostics and assessment of degenerative disc pathologies should be centered on the clinical problem. The basis for this is the use of a uniform terminology between the disciplines involved.

[Intracranial cystic lesions]. / Intrakranielle zystische Läsionen.

CLINICAL PROBLEM: Intracerebral cysts are common findings in imaging of the neurocranium and are not always clinically significant. The pathological spectrum of intracerebral cysts is, however, very broad and in addition to incidental findings includes developmental disorders, malformation tumors, primary and secondary neoplasms and infectious etiologies, such as cerebral abscess formation, cysticercosis or residuals after congenital cytomegalovirus infections. Intracerebral cystic defects may be caused by inflammatory central nervous system (CNS) diseases, such as multiple sclerosis as well as by mitochondriopathies, leukodystrophy, electrolyte disturbances or osmotic demyelination syndrome or brain infarctions, e.g. after lacunar infarctions or as encephalomalacic changes after severe traumatic brain injury. RADIOLOGICAL STANDARD PROCEDURES: In addition to the radiological findings of cysts in magnetic resonance imaging (MRI) or in computed tomography (CT), the localization, patient age, patient medical history and laboratory diagnostics are helpful for the differential diagnostics. METHODICAL INNOVATION: In addition to the morphological assessment, advanced MRI techniques, such as diffusion-weighted imaging for epidermoids or the use of MR spectroscopy, can provide valuable information for the differential diagnosis. PERFORMANCE/ASSESSMENT: Intracranial cysts can be subdivided into intraventricular and periventricular cysts, intra-axial cysts and cysts in the external fluid-filled spaces. Associated tumor nodules and the contrast medium behavior of the cyst walls and/or associated soft tissue components as well as the reaction of the adjacent parenchyma are helpful for the diagnosis and assessment.

[Postoperative spine]. / Postoperative Wirbelsäule.

Approximately 15-30 % of surgical procedures involving the lumbar spine are associated with complications that require further diagnostic work-up. The choice of imaging modality for postoperative complications depends on the extent, pattern and temporal evolution of the postoperative neurological signs and symptoms as well as on the preoperative clinical status, the surgical procedure itself and the underlying pathology. The interpretation of imaging findings, in particular the distinction between postoperative complications and normally expected nonspecific postoperative imaging alterations can be challenging and requires the integration of clinical neurological information and the results of laboratory tests. The combination of different imaging techniques might help in cases of equivocal imaging results.

[Spinal cord infarction]. / Spinaler Infarkt.

Infarction of the spinal cord can cause a variety of symptoms and neurological deficits because of the complex vascular supply of the myelon. The most common leading symptom is distal paresis ranging from paraparesis to tetraplegia caused by arterial ischemia or infarction of the myelon. Venous infarction, however, cannot always be distinguished from arterial infarction based on the symptoms alone.Modern imaging techniques, such as computed tomography angiography (CTA) and magnetic resonance angiography (MRA) assist in preoperative planning of aortic operations to reliably identify not only the most important vascular structure supplying the spinal cord, the artery of Adamkiewicz, but also other pathologies such as tumors or infectious disorders. In contrast to CT, MRI can reliably depict infarction of the spinal cord.

[Postoperative findings in the spinal column]. / Postoperative Befunde an der Wirbelsäule.

Postoperative imaging after spinal surgery is usually performed to document the correct positioning of implants or to rule out complications if patients still suffer from pain after surgery. Depending on the question various imaging modalities can be used all of which have benefits and limitations. Conventional X-ray is used for the documentation of the correct positioning of spinal implants, stability (olisthesis) and during follow-up to rule out fractures or instability of the implants, whereas soft tissue changes cannot be completely assessed. Besides these indications, imaging is usually performed because of ongoing symptoms (pain for the most part) of the patients. Soft tissue changes including persistent or recurrent herniated disc tissue, hematoma or infection can best be depicted using magnetic resonance imaging (MRI) which should be performed within the immediate postoperative period to be able to distinguish physiological development of scar tissue from inflammatory changes in the area of the surgical approach. Often imaging alone cannot differentiate between these and imaging can therefore only be considered as an adjunct. Computed tomography is the modality of choice for the evaluation of bony structures and an adjunct of new therapies such as image-guided application of cement for kyphoplasty or vertebroplasty.

[Multiple sclerosis]. / Multiple Sklerose.

Multiple sclerosis is the most common chronic inflammatory disease of myelin with interspersed lesions in the white matter of the central nervous system. Magnetic resonance imaging (MRI) plays a key role in the diagnosis and monitoring of white matter diseases. This article focuses on key findings in multiple sclerosis as detected by MRI.

[Cubital tunnel syndrome--simple nerve decompression or decompression with subcutaneous anterior transposition?]. / Sulcus-ulnaris-Syndrom: Einfache Dekompression oder subkutane Vorverlagerung?

The purpose of this prospective, randomised and controlled study was to evaluate which kind of operative technique for treatment of cubital tunnel syndrome is favourable: subcutaneous anterior transposition or nerve decompression without transposition. This study included 66 patients suffering from pain and/either neurological deficits with clinically and electrographically proven cubital tunnel syndrome. 32 patients underwent nerve decompression without transposition, whereas 34 underwent subcutaneous transposition of the nerve. Follow-up examinations evaluating pain, motor and sensory deficits as well as motor nerve conduction velocities were performed three, nine and 24 months postoperatively. Irrespectively of operative procedures (simple decompression vs. subcutaneous anterior transposition) there were no significant differences between the outcomes of the two groups at either postoperative follow-up examination (p > 0.05).

Disc replacement using Pro-Disc C versus fusion: a prospective randomised and controlled radiographic and clinical study.

Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.

[Spondylitis/spondylodiscitis]. / Spondylitis/Spondylodiszitis.

Spondylitis is an inflammation of the vertebral body. If the infection is manifested in the vertebral motor segment it is called spondylodiscitis, which can be divided into specific and nonspecific forms. It is clinically impressive that at the beginning of the disease, the patients who are quite often immunosuppressed suffer from localized, especially nocturnally exacerbated backache. The initial diagnostic work-up generally consists of clinical history, examination, laboratory tests, and (especially advanced) imaging findings. Although computed tomography still remains the most frequently used advanced imaging technique, magnetic resonance imaging is the golden standard for the diagnosis of spondylitis and spondylodiscitis.

[Skull base tumors]. / Tumoren der Schädelbasis.

Modern imaging techniques have great importance in the diagnosis and therapy of skull-base pathologies. Many of these lesions, especially in relation to their specific location, can be evaluated using CT and MR imaging. Tumors commonly found in the anterior skull base include carcinoma, rhabdomyosarcoma, esthesioneuroblastoma and meningioma. In the central cranial fossa, nasopharyngeal carcinoma, metastases, meningioma, pituitary adenoma and neurinoma have to be considered. The most common neoplasms of the posterior skull base, including the CP angle, are neurinoma, meningioma, nasopharyngeal carcinoma, chordoma and paraganglioma. One major task of imaging is the evaluation of the exact tumor extent as well as its relationship to the neighboring neurovascular structures. The purpose of this review is to recapitulate the most important anatomical landmarks of the skull base. The typical imaging findings of the most common tumors involving the skull base are also presented.