Musculoskeletal interventional radiology: ultrasound and CT. / Intervencionismo en musculoesquelético. Ecografía y tac.

We aim to describe imaging-guided (ultrasound and CT) interventional techniques in the musculoskeletal system that can be performed by general radiologists, whether in hospitals, primary care clinics, private offices, or other settings. The first requirement for doing these procedures is adequate knowledge of the anatomy of the musculoskeletal system. The second requirement is to inform the patient thoroughly about the technique, the risks involved, and the alternatives available in order to obtain written informed consent. The third requirement is to ensure that the procedure is performed in accordance with the principles of asepsis in relation to the puncture zone and to all the material employed throughout the procedure. The main procedures that can be done under ultrasound guidance are the following: fine needle aspiration cytology (FNAC), core needle biopsy (CNB), diagnostic and/or therapeutic arthrocentesis, drainage of juxta-articular fluid collections, drainage of abscesses, drainage of hematomas, treatment of Baker's cyst, treatment of ganglia, treatment of bursitis, infiltrations and treatment of plantar fasciitis, plantar fibrosis, epicondylitis, Achilles tendinopathy, and Morton's neuroma, puncture and lavage of calcifications in calcifying tendinopathy. We also review the following CT-guided procedures: diagnosis of spondylodiscitis, FNAC of metastases, arthrography, drainages. Finally, we also mention more complex procedures that can only be done in appropriate settings: bone biopsies, treatment of facet joint pain, radiofrequency treatment.

Guidelines for magnetic resonance imaging in axial spondyloarthritis: A Delphi study.

OBJECTIVE: The term axial spondyloarthritis refers to a group of chronic inflammatory rheumatic diseases with a common genetic basis that course with axial and peripheral involvement and enthesitis. Recently, the Assessment of SpondyloArthritis international Society (ASAS) established some diagnostic criteria, including for the first time magnetic resonance imaging (MRI) findings. Given the difficulties of obtaining MRI in some environments and the lack of experience with axial spondyloarthritis, a group of radiologists and rheumatologists sought to establish some practical guidelines to ensure the correct use of MRI in this disease. MATERIAL AND METHODS: Using the Delphi method, we used a questionnaire with 49 items stratified into 4 blocks to survey 46 experts in the MRI diagnosis of axial spondyloarthritis. RESULTS: The experts agreed on 82% of the items. The degree of agreement was 100% in the block "Importance of early diagnosis of axial spondyloarthritis", 69% in the block "Optimization of the use of MRI in the diagnosis of axial spondyloarthritis", 93% in the block "Use of MRI in axial spondyloarthritis: Technical aspects", and 57% in the block "Usefulness of MRI in the prognosis, follow-up, and evaluation of the response to treatment in axial spondyloarthritis". CONCLUSIONS: Despite the importance of MRI in the early diagnosis of axial spondyloarthritis, this study shows the need for standardization and points to relative disagreement about how to use MRI in the follow-up of the disease and evaluation of the response to treatment. The results of this study can help improve the use of MRI in axial spondyloarthritis.

Accuracy of magnetic resonance imaging in differentiating between benign and malignant vertebral lesions: role of diffusion-weighted imaging, in-phase/opposed-phase imaging and apparent diffusion coefficient.

OBJECTIVE: To determine the ability of MRI to distinguish between benign and malignant vertebral lesions. MATERIAL AND METHODS: We included 85 patients and studied a total of 213 vertebrae (both pathologic and normal). For each vertebra, we determined whether the lesion was hypointense in T1-weighted sequences and whether it was hyperintense in STIR and in diffusion-weighted sequences. We calculated the in-phase/out-of-phase quotient and the apparent diffusion coefficient for each vertebra. We combined parameters from T1-weighted, diffusion-weighted, and STIR sequences to devise a formula to distinguish benign from malignant lesions. RESULTS: The group comprised 60 (70.6%) women and 25 (29.4%) men with a mean age of 67±13.5 years (range, 33-90 y). Of the 85 patients, 26 (30.6%) had a known primary tumor. When the lesion was hypointense on T1-weighted sequences, hyperintense on STIR and diffusion-weighted sequences, and had a signal intensity quotient greater than 0.8, the sensitivity was 97.2%, the specificity was 90%, and the diagnostic accuracy was 91.2%. If the patient had a known primary tumor, these values increased to 97.2%, 99.4%, and 99%, respectively. CONCLUSION: Benign lesions can be distinguished from malignant lesions if we combine the information from T1-weighted, STIR, and diffusion-weighted sequences together with the in-phase/out-of-phase quotient of the lesion detected in the vertebral body on MRI.

Diagnostic accuracy of lumbar CT and MRI in the evaluation of chronic low back pain without red flag symptoms.

BACKGROUND: Low back pain (LBP) is one of the most frequent reasons for medical consultation. Most of the patients will have nonspecific LBP, which usually are self-limited episodes. It is unclear which of the diagnostic imaging pathways is most effective and costeffective and how the imaging impacts on patient treatment. Imaging techniques are usually indicated if symptoms remain after 6 weeks. Magnetic resonance imaging (MRI) is the diagnostic imaging examination of choice in lumbar spine evaluation of low back pain; however, availability of MRI is limited. OBJECTIVES: To evaluate the diagnostic accuracy of computed tomography (CT) with MRI (as standard of reference) in the evaluation of chronic low back pain (LBP) without red flags symptoms. To compare the results obtained by two radiologists with different grades of experience. MATERIALS AND METHODS: Patients with chronic low back pain without red flags symptoms were retrospectively reviewed by two observers with different level of experience. Patients included had undergone a lumbar or abdominal CT and an MRI within a year. Once the radiological information was collected, it was then statistically reviewed. The aim of the statistical analysis is to identify the equivalence between both diagnostic techniques. To this end, sensitivity, specificity and validity index were calculated. In addition, intra and inter-observer reliability were measured by Cohen's kappa values and also using the McNemar test. RESULTS: 340 lumbar levels were evaluated from 68 adult patients with chronic low back pain or sciatica. 63.2% of them were women, with an average age of 60.3 years (SD 14.7). CT shows high values of sensitivity and specificity (>80%) in most of the items evaluated, but sensitivity was low for the evaluation of density of the disc (40%) and for the detection of disc herniation (55%). Moreover, agreement between MRI and CT in most of these items was substantial or almost perfect (Cohen's kappa-coefficient > 0'8), excluding Modic changes (kappa = 0.497), degenerative changes (kappa0.688), signal of the disc (kappa = 0.327) and disc herniation (kappa = 0.639). Finally, agreement between both observers is mostly high (kappa > 0.8). Foraminal stenosis, canal stenosis and the grade of the canal stenosis were overdiagnosed by the inexperienced observer in the evaluation of CT images. CONCLUSIONS AND SIGNIFICANCE: CT is as sensitive as lumbar MRI in the evaluation of most of the items analysed, excluding Modic changes, degenerative changes, signal of the disc and disc herniation. In addition, these results are obtained regardless the experience of the radiologist. The rising use of diagnostic medical imaging and the improvement of image quality brings the opportunity of making a second look of abdominal CT in search of causes of LBP. Thereby, inappropriate medical imaging could be avoided (2). In addition, it would allow to reduce MRI waiting list and prioritize other patients with more severe pathology than LBP.

[Imaging-guided percutaneous biopsy of tumors of the locomotor apparatus]. / Biopsia percutánea guiada por técnicas de imagen en patología tumoral del aparato locomotor.

The prognosis of musculoskeletal sarcomas is related to appropriate management by specifically trained multidisciplinary teams. Musculoskeletal radiologists are responsible for the image-guided percutaneous biopsy of these tumors, which has a diagnostic accuracy of at least 80%. It is essential for radiologists to know: a) the limitations of percutaneous biopsy with respect to surgical biopsy; b) what should and should not be biopsied; c) how to appropriately plan percutaneous biopsy, with special attention to the route of approach, taking into account the compartmental anatomy and the route of approach after surgical treatment; and d) technical aspects of the procedure, like the area of the tumor to biopsy, the caliber of the needle, the number and length of the specimens to obtain to ensure optimal pathological diagnosis, and techniques in function of the imaging modality and bone penetration.

Microsurgical technique for previously coiled aneurysms.

Since the introduction of Guglielmi detachable coils to treat intracranial aneurysms in 1991, the number of patients undergoing endovascular coiling has continuously risen as well as the number of those residual and recurrent previously coiled aneurysms that necessitate a microsurgical occlusion. Between July 1995 and August 2009 we retrospectively analyzed 81 patients with 82 previously coiled aneurysms treated microsurgically at two Finnish Neurosurgical University Hospitals, Helsinki and Kuopio. Fifty-eight aneurysms (71%) were located at anterior circulation and 24 (29%) at posterior circulation. Fifteen patients were operated on within the first month (early surgery) after coiling, whereas 66 were treated later (late surgery). Complete or partial removal of coils during surgery may facilitate clipping, but is significantly (P<0.001) more difficult to accomplish in late surgery. Removal of coils may also increase the chance for poor outcome. Chance of poor outcome increased also with intraoperative aneurysm rupture, size of the aneurysm and posterior circulation location. Good clinical outcome, three months after surgery, was achieved in 71 patients (88%); four patients were severely disabled, and six patients died (three of them due to poor clinical condition). Complete microsurgical occlusion of the residual previously coiled aneurysm is a high-risk procedure in large and giant aneurysms, and these patients should be referred to a dedicated neurovascular center to minimize surgical complications. Bypass procedures may be the best option for demanding growing lesions, especially those in posterior circulation.

[Usefulness of IPC continuous monitoring in shunt dysfunction]. / Utilidad de la monitorizacion de la PIC en pacientes con sospecha de disfuncion valvular.

Shunt dysfunction is a common situation in neurosurgery. Often symptoms, physical examination and radiology are not enough to set a diagnosis. ICP continuous monitoring is a safe and reliable tool that provides valuable information about CSF dynamics in these patients. Not only quantitative analysis is needed but also a qualitative one that enables pathological waves identification, because high amplitude B waves are strongly related to shunt dysfunction. In this paper experience about ICP continuous monitoring in patients with shunt dysfunction suspect is presented. Quantitative and qualitative data analysis led to a correct diagnosis, improving all the patients treated according to this criterion. An intraparenchymatous Camino® sensor and neuroPICture software (developed by first author) for data collection and graphic representation were used. Complications related to monitoring were absent and graphics obtained useful for qualitative analysis.

[Aneurysmal subarachnoid hemorrhage: group of study of cerebrovascular pathology of the Spanish society of neurosurgery management guideline]. / Hemorragia subaracnoidea aneurismática: guía de tratamiento del grupo de patología vascular de la sociedad Española de neurocirugía.

An actualized revision of the most important aspects of aneurismal subarachnoid hemorrhage is presented from the guidelines previously published by the group of study of cerebrovascular pathology of the Spanish Society of Neurosurgery. The proposed recommendations should be considered as a general guide for the management of this pathological condition. However, they can be modified, even in a significant manner according to the circumstances relating each clinical case and the variations in the therapeutic and diagnostic procedures available in the center attending each patient.

Percutaneous management of bone metastases: State of the art.

Interventional radiology is playing an increasingly important role in the local treatment of bone metastases; this treatment is usually done with palliative intent, although in selected patients it can be done with curative intent. Two main groups of techniques are available. The first group, centered on bone consolidation, includes osteoplasty/vertebroplasty, in which polymethyl methacrylate (PMMA) is injected to reinforce the bone and relieve pain, and percutaneous osteosynthesis, in which fractures with nondisplaced or minimally bone fragments are fixed in place with screws. The second group centers on tumor ablation. tumor ablation refers to the destruction of tumor tissue by the instillation of alcohol or by other means. Thermoablation is the preferred technique in musculoskeletal tumors because it allows for greater control of ablation. Thermoablation can be done with radiofrequency, in which the application of a high frequency (450 Hz-600 Hz) alternating wave to the tumor-bone interface achieves high temperatures, resulting in coagulative necrosis. Another thermoablation technique uses microwaves, applying electromagnetic waves in an approximate range of 900 MHz-2450 MHz through an antenna that is placed directly in the core of the tumor, stimulating the movement of molecules to generate heat and thus resulting in coagulative necrosis. Cryoablation destroys tumor tissue by applying extreme cold. A more recent, noninvasive technique, magnetic resonance-guided focused ultrasound surgery (MRgFUS), focuses an ultrasound beam from a transducer placed on the patient's skin on the target lesion, where the waves' mechanical energy is converted into thermal energy (65 °C-85 °C). Treatment should be planned by a multidisciplinary team. Treatment can be done with curative or palliative intent. Once the patient is selected, a preprocedural workup should be done to determine the most appropriate technique based on a series of factors. During the procedure, protective measures must be taken and the patient must be closely monitored. After the procedure, patients must be followed up.

Idiopathic subarachnoid hemorrhage: a multicentre series of 220 patients.

BACKGROUND. The Spanish neurosurgical society created a multicentre data base on spontaneous SAH to analyze the real problematic of this disease in our country. This paper focuses on the group of patients with idiopathic SAH (ISAH). METHODS. 16 participant hospitals collect their spontaneous SAH cases in a common data base shared in the internet through a secured web page, considering clinical, radiological, evolution and outcome variables. The 220 ISAH cases collected from November 2004 to November 2007 were statistically analyzed as a whole and divided into 3 subgroups depending on the CT blood pattern (aneurysmal, perimesencephalic, or normal). RESULTS. The 220 ISAH patients constitute 19% of all 1149 spontaneous SAH collected in the study period. In 46,8% of ISAH the blood CT pattern was aneurysmal, which was related to older age, worse clinical condition, higher Fisher grade, more hydrocephalus and worse outcome, compared to perimesencephalic (42.7%) or normal CT (10.4%) pattern. Once surpassed the acute phase, outcome of ISAH patients is similarly good in all 3 ISAH subgroups, significantly better as a whole compared to aneurysmal SAH patients. The only variable related to outcome in ISAH after a logistic regression analysis was the admission clinical grade. CONCLUSIONS. ISAH percentage of spontaneous SAH is diminishing in Spain. Classification of ISAH cases depending on the blood CT pattern is important to differentiate higher risk groups although complications are not negligible in any of the ISAH subgroups. Neurological status on admission is the single most valuable prognostic factor for outcome in ISAH patients.

["Idiopathic" syringomyelia: report of a case]. / Siringomielia "idiopática"; a propósito de un caso.

Syringomyelia is the condition in which cavities fulfilled with CSF are found within spinal cord. Syringes are caused by obstructions of CSF pathways of different causes. If we can not find a cause responsible for the blockage, we call it "idiopathic" syringomyelia. Drainage procedures have been widely used but results, especially long-term results, are not favourable and complication rate is high. Some authors prefer to restore CSF circulation instead to drain the syrinx. Results of this treatment modality are better in literature than drainage procedures. Adequate radiological studies help to identify problem location and to plan the approach. A case of "idiopathic" syringomyelia is presented. Treatment consisted on arachnoid webs dissection and dural plastia. Clinical and radiological response was good. Literature concerned about this kind of syringomyelia and treatment modalities are reviewed.

[Spontaneous Subarachnoid Haemorrhage multicenter database from the Group for the Study of Vascular Pathology of the Spanish Society for Neurosurgery: presentation, inclusion criteria and development of an internet-based registry]. / Base de datos multicéntrica de hemorragia subaracnoidea espontánea del Grupo de Trabajo de Patología Vascular de la Sociedad Española de Neurocirugía: presentación, criterios de inclusión y desarrollo de una base de datos en internet.

INTRODUCTION: Subarachnoid haemorrhage is one of the most severe neurosurgical diseases. Its study is crucial for improving the care of these patients in our environment. With this goal the Group for the Study of Neurovascular Pathology of the Spanish Society for Neurosurgery (SENEC) decided to create a multicenter registry for the study of this disease. MATERIALS AND METHODS: In this database we have prospectively included all cases with spontaneous subarachnoid haemorrhage admitted to the participant hospitals from November 2004 to November 2007. The fields to be included in the database were selected by consensus, including age, past medical history, clinical characteristics at admission, radiological characteristics including presence or absence of an aneurysm and its size and location, type and complications of the aneurysm treatment, outcome assessed by the Glasgow Outcome Scale (GOS) at discharge and six months after the bleeding as well as the angiographic result of the aneurysm treatment. All fields were collected by means of an electronic form posted in secure web page. RESULTS: During the three years of study a total of 1149 patients have been included by 14 Hospitals. The time needed to fill in a patient in the registry is approximately 3.4 minutes. This series of patients with spontaneous SAH is similar to other non-selected in-hospital series of SAH. The mean age of the patients is 55 years and there is a 4:3 female to male ratio. In relation to the severity of the bleeding 32% of the patients were in poor clinical grade at admission (WFNS 4 or 5). 5% of the patients died before angiography could be performed. An aneurysm was confirmed as the origin of the bleeding in 76% of the patients (aSAH), while in 19% of the patients no lesion was found in the angiographic studies and were thus classified as idiopathic subarachnoid hemorrhage (ISAH). Of those patients with aSAH, 47% were treated endovascularly, 39% surgically, 3% received a combined treatment and 11% did not receive any treatment for their aneurysm because of early death. Regarding outcome, there is a 22% mortality in the series. Only 40% of the patients with aSAH reached a good outcome at discharge (GOS = 5). CONCLUSIONS: Spontaneous SAH continues to be a disease with high morbidity and mortality. This database can be an ideal instrument for improving the knowledge about this disease in our environment and to achieve better results. It would be desirable that this database could in the future be the origin of a national registry of spontaneous SAH.

Morel-Lavallée lesion: diagnosis and treatment with imaging techniques. / Lesión de Morel-Lavallée: diagnóstico y tratamiento con técnicas de imagen.

OBJECTIVES: We aim to review the characteristics of Morel-Lavallée lesions and to evaluate their treatment. MATERIAL AND METHODS: We retrospectively reviewed 17 patients (11 men and 6 women; mean age, 56.1 years, range 25-81 years) diagnosed with Morel-Lavallée lesions in two different departments. All patients underwent ultrasonography, 5 underwent computed tomography, and 9 underwent magnetic resonance imaging. Percutaneous treatment with fine-needle aspiration and/or drainage with a 6F-8F catheter was performed in 13 patients. Two patients required percutaneous sclerosis with doxycycline. RESULTS: All patients responded adequately to percutaneous treatment, although it was necessary to repeat the procedure in 4 patients. CONCLUSIONS: Radiologists need to be familiar with this lesion that can be treated percutaneously in the ultrasonography suite when it is not associated with other entities.

[Nitric oxide in malignant astrocytes]. / El monóxido de nitrógeno en los astrocitomas malignos.

INTRODUCTION: One of the different molecules involved in the development of astrocytomas is nitric oxide (NO), a gaseous radical that, depending on the cell type and the experimental paradigm selected in the pathology, can play either a cytotoxic or a cytoprotective role. DEVELOPMENT: During the development of an astrocytoma NO acts as a tumouricidal agent, although it can also alter vascular reactivity and lead to neovascularisation, thereby contributing to the invasive capacity (aggressiveness) of the tumour. One of the mechanisms of tumoural progression consists in the protein inactivation resulting from the NO nitration of tyrosine from proteins coded for by tumour-suppressing genes, such as p53. Furthermore, in malignant astrocytes, nitrosoglutathione, a natural NO-donor, has been seen to play a role in the chemoresistance displayed against nitrosourea derivatives. The NO excreted by irradiated astrocytoma cells also appears to be involved in the resistance to the radiotherapy shown by non-irradiated cells. CONCLUSIONS: The molecular mechanisms behind the complex and paradoxical activity of NO in glioblastoma multiforme have still not been fully explained and its implications in vivo are even further from being completely understood.

False positive thallium-201 SPECT imaging in brain abscess.

Three cases of intracranial 201Tl uptake, reported as positive tumour activity in patients with a final diagnosis of abscess, are described. 201Tl has been proposed as a useful oncotropic radiotracer in the diagnosis of brain tumour activity. These cases suggest a note of caution in the interpretation of 201Tl brain images in the differential diagnosis of an intracranial expanding mass.

[Cerebellopontine angle lipoma: clinical case]. / Lipoma del ángulo pontocerebeloso: caso clínico.

Lipomas of the cerebellopontine angle are extremely rare. These tumors are probably maldevelopment lesions which can cause slowly progressive neurological symptoms. Including the present case, 90 lipomas in this localization have been described in the literature. The authors report a case of cerebellopontine angle lipoma in a 44-year-old male patient who suffered right hearing loss and tinnitus during seven months. The literature concerning this rare cerebellopontine angle tumor is review. The symptoms, radiological features and surgical management are discussed.

[Central neurocytoma: analysis of three cases and review of the literature]. / Neurocitoma central: a propósito de tres casos y revisión de la literatura.

INTRODUCTION AND CLINICAL CASES: Three cases of central neurocytoma, confirmed by immunohistochemical study are reported. The central neurocytoma has recently been added to the differential diagnosis of intraventricular tumors. It is more frequent than previously thought, with high incidence in young patients. The positivity for synaptophysin and neuron specific enolase, the negativity for neurofilament protein and glial fibrillary acid protein, and the finding of elements of neuronal differentiation on electron microscopy, are the main pathological features of these tumors. CONCLUSION: The surgical treatment is the election, and radiotherapy is reserved for malignant cases or recurrence.

[Percutaneous radiofrequency ablation of benign bone tumors: osteoid osteoma, osteoblastoma, and chondroblastoma]. / Tratamiento mediante radiofrecuencia percutánea de los tumores óseos benignos: osteoma osteoide, osteoblastoma y condroblastoma.

We report our experience in the computed tomography (CT)-guided percutaneous radiofrequency ablation of more than 100 benign bone tumors in the last eight years. We affirm that this should be the technique of choice in the vast majority of osteoid osteomas; it can also be applied as a definitive treatment in many cases of osteoblastomas or chondroblastomas as well as in less common benign bone tumors. CT-guided percutaneous radiofrequency ablation has proven highly efficacious and has resulted in very few complications; thus, patients tend to recover very quickly.

[Carpal tunnel syndrome in childhood.]. / Síndrome del túnel carpiano en la infancia.

Introduction. Carpal tunnel syndrome (CTS) has usually a different clinical presentation in children compared to adults. On top of this, its rarity in childhood makes it difficult to diagnose. It has also different etiologies at this age, the majority of cases occur in children with lysosomal storage diseases (mucopolysaccharidosis and mucolipidosis) which may be the first manifestation of this disease in some cases. Clinical case. In this article we describe 3 cases of children aged between 4 and 10 years, 2 with idiopathic CTS and 1 with primary familial origin. The symptoms of the former were intermittent paresthesias and handling difficulty, while the familial case presented with a more typical paresthesias and pain. The neurophysiological study confirmed the diagnosis. Concerning the patient with a history of CTS in the family, MRI showed a compression of the nerve due to the thickening of the flexor retinaculum. In all cases, lysosomal storage disease was ruled out and a conservative treatment was initiated. Evolution was favorable in the idiopathic cases, one of them with an almost complete remission of symptoms, while the patient with a familial CTS follows a progressive course and is waiting for the surgical assessment. Discussion. The CTS in pediatric age presents milder and more unspecific symptoms than in adults, and the results of the exploration and provocation tests are often unclear. Surgical treatment is almost always necessary, although some idiopathic cases, particularly if they are not associated to the thickening of the flexor retinaculum, may improve with a conservative treatment.