RESUMEN
BACKGROUND: Intraneural ganglion cysts of the obturator nerve are rare. Our aim is to review cases of obturator intraneural ganglion cysts at our institution and those reported in the literature. METHODS: We reviewed all cases evaluated by the senior author. A literature search was performed using the PubMed database and Google Scholar with the following terms: "obturator cyst," "obturator intraneural ganglion cyst," and "obturator intraneural ganglia." All cases underwent a retrospective review. Patient demographic data, including age, sex, and presenting signs and symptoms were recorded. Imaging studies were re-evaluated by 2 musculoskeletal radiologists experienced in the diagnosis of intraneural ganglion cysts. RESULTS: We identified 2 cases of obturator intraneural ganglia at our institution; both were connected to the hip joint. We found 4 cases that were clearly diagnosed as intraneural ganglia in the literature, of which only 1 was recognized by the original authors as being joint connected, but based on our reinterpretation, 3 of 4 were joint connected. An additional 9 cases identified in the literature did not definitely report the nerve-cyst relationship, but based on our reinterpretation, were believed to be intraneural; 8 were joint connected. CONCLUSIONS: We believe that obturator intraneural ganglion cysts adhere to the principles of the unifying articular theory. They arise from the anteromedial hip joint and extend into an articular branch and can reach the parent obturator nerve. Surgery should address the hip disease and/or the articular branch connection. Not appreciating the pathoanatomy of these cysts can lead to persistent or recurrent cysts.
Asunto(s)
Ganglión/cirugía , Adulto , Anciano , Electromiografía , Femenino , Ganglión/diagnóstico por imagen , Ganglión/patología , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/patología , Articulación de la Cadera/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Debilidad Muscular/etiología , Nervio Obturador/diagnóstico por imagen , Nervio Obturador/patología , Nervio Obturador/cirugía , Dolor Postoperatorio/etiología , Dolor Postoperatorio/cirugía , Estudios Retrospectivos , Espondiloartropatías/etiología , Adulto JovenRESUMEN
Adamantinoma of the long bones is a rare, typically low-grade malignant tumor that frequently involves the tibia. Radiographically, adamantinoma is characteristically a lytic, intracortical, and expansile lesion with variable margins. Histologically, adamantinoma is a bimorphic neoplasm, composed of epithelial and osteofibrous elements. Herein, we describe a 72-year-old man with a long-standing tibial mass that, on imaging, rapidly developed cortical destruction with soft tissue extension. Imaging revealed no evidence of a distant site of origin. Needle core biopsy demonstrated high-grade squamous cell carcinoma, and metastasis was initially favored. However, the combined clinicoradiologic and pathologic features were most compatible with a high-grade squamous cell carcinoma arising in adamantinoma. The diagnosis was confirmed in the resection specimen. Both the age at presentation and histologic features make this case unusual and highlight a potential for misdiagnosis in the evaluation of squamous cell carcinoma-containing lesions of the tibia, reinforcing the importance of clinicoradiologic correlation in bone pathology.
Asunto(s)
Adamantinoma/patología , Neoplasias Óseas/patología , Carcinoma de Células Escamosas/patología , Neoplasias Primarias Múltiples/patología , Tibia/patología , Anciano , Humanos , MasculinoRESUMEN
A number of nonneoplastic conditions can mimic tumors of bone. Some of the more common mimics of primary bone tumors include infectious, inflammatory, periosteal, and degenerative joint disease-associated lesions that produce tumorlike bone surface-based or intraosseous lesions. This article considers a spectrum of reactive and nonreactive processes including stress fracture, subchondral cysts, osteonecrosis, heterotopic ossification, osteomyelitis, sarcoidosis, and amyloidoma that can present in such a way that they are mistaken for a tumor arising primary in bone.
Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/patología , Quistes Óseos/diagnóstico por imagen , Quistes Óseos/patología , Enfermedades Óseas/diagnóstico por imagen , Enfermedades Óseas/patología , Diagnóstico Diferencial , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/patología , Humanos , Osificación Heterotópica/diagnóstico por imagen , Osificación Heterotópica/patología , Osteomielitis/diagnóstico por imagen , Osteomielitis/patología , Osteonecrosis/diagnóstico por imagen , Osteonecrosis/patologíaRESUMEN
Whole-body fluorine 18 fluorodeoxyglucose (FDG) positron-emission tomography (PET)/computed tomography (CT) is performed primarily for oncologic indications; however, FDG uptake is not specific for malignancy. Herein we focus on causes of increased FDG uptake in and around joints, as lesions in these locations are commonly benign. A combination of primary intra-articular processes and osseous processes that may occur near the joint space will be discussed. Causes of intra-articular and periarticular increased FDG activity can be broadly divided into infectious, inflammatory, degenerative, and benign neoplastic categories. A familiarity with the full range of these processes is important to avoid misinterpretation, in turn decreasing unnecessary follow-up studies, procedures, and treatments. Differentiation from malignancy is often possible on the basis of a different level of FDG activity, divergent response to therapy, or differing changes over time, in comparison with a patient's known primary cancer. Recognizing an intra-articular lesion location can also be critical, as intra-articular metastases are rare. In some cases, benign FDG-avid articular and periarticular entities have a specific appearance at FDG PET/CT and a correct diagnosis may be made without any additional workup. In most other cases, comparison with prior studies and/or additional imaging can afford an accurate diagnosis. This review is meant to introduce the reader to a spectrum of benign FDG-avid articular and periarticular processes that may be encountered at oncologic FDG PET/CT to increase confidence and diagnostic accuracy. (©)RSNA, 2016.
Asunto(s)
Fluorodesoxiglucosa F18 , Artropatías/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Diagnóstico Diferencial , Humanos , Neoplasias/diagnóstico por imagenRESUMEN
The peripheral nervous system is susceptible to a diverse array of pathologic insults, broadly categorizable into those entities intrinsic to the nerves themselves, either primarily arising within the nerve(s) or direct involvement of the nerve(s) secondary to a systemic process, and those processes external to the nerve(s) proper but affecting them extrinsically via mass effect, such as entrapment neuropathies. The soft tissue contrast inherent to high-quality MR imaging allows for outstanding visualization of the peripheral nervous system and surrounding structures. This review focuses on the use of MR imaging in the diagnosis and management of peripheral nerve disorders of the upper extremity.
Asunto(s)
Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Extremidad Superior/inervación , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodosRESUMEN
MRI of the peripheral nerves continues to grow technologically and in clinical use. This article reviews the technological aspects and basic interpretation of high-resolution MR imaging of the upper extremity nerves. These techniques work with 1.5-, or preferably 3-T, scanners regardless of vendors. The article also includes selected pitfalls in the interpretation of upper extremity nerve MRI.
Asunto(s)
Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Extremidad Superior/inervación , Medios de Contraste , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología TridimensionalRESUMEN
The clinical and imaging evaluation of peripheral neuropathies in patients with cancer is challenging. It is critically important to differentiate malignant invasion of the peripheral nervous system from nonmalignant causes, such as radiation-induced neuritis, neuropathy associated with chemotherapy, and inflammatory neuropathies. Contrast material-enhanced magnetic resonance (MR) imaging is the initial noninvasive test of choice; however, interpretation can be challenging when the anatomic features are distorted by prior surgery, radiation, or both. Fluorine 18 ((18)F)-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is an imaging adjunct to MR imaging that is particularly helpful for evaluating peripheral nerves because the metabolic activity depicted with (18)F-FDG PET/CT helps differentiate malignant from benign disease and assists in making certain management decisions. For example, sites of high (18)F-FDG activity in a peripheral nerve can be targeted to increase the diagnostic yield of a biopsy because malignant involvement of peripheral nerves can be patchy. Of note, (18)F-FDG PET/CT can show clinically unsuspected metastases elsewhere in the body. If cancer is found, (18)F-FDG PET/CT allows excellent assessment of treatment response. (18)F-FDG PET/CT is also useful in evaluating primary nerve sheath tumors in that such tumors with low metabolic activity on FDG PET/CT images are unlikely to be malignant, although the specificity is limited. It is essential to have a good understanding of the imaging characteristics of benign and malignant causes of peripheral neuropathy if (18)F-FDG PET/CT is to be used effectively for accurate diagnosis.
Asunto(s)
Imagen Multimodal , Neoplasias del Sistema Nervioso Periférico/diagnóstico , Sistema Nervioso Periférico/anatomía & histología , Medios de Contraste , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada por Rayos XRESUMEN
We present a case of a biopsy-proven intraneural perineurioma involving the left lumbosacral and brachial plexus with prominent hemi-body port wine stains in the associated dermatomes. The relationship between the two entities is not clear, but this case may provide a clue to understanding the etiological pathogenesis of intraneural perineurioma in the future.
Asunto(s)
Neoplasias de la Vaina del Nervio/complicaciones , Neoplasias de la Vaina del Nervio/patología , Paresia/etiología , Neoplasias del Sistema Nervioso Periférico/complicaciones , Neoplasias del Sistema Nervioso Periférico/patología , Mancha Vino de Oporto/etiología , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Paresia/diagnóstico , Mancha Vino de Oporto/diagnósticoRESUMEN
Osseous sarcoidosis of the axial skeleton is typically asymptomatic and not routinely imaged with MRI. The natural history of sarcoidosis is generally felt to be resolution spontaneously or with treatment, or unremitting progression. We report a case of recurrent active symptomatic disease after an initial response to immunomodulator treatment with an unusual halo of T2-hyperintensity surrounding treated fibrofatty vestigial lesions.
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Antiinflamatorios/uso terapéutico , Enfermedades Óseas/diagnóstico , Enfermedades Óseas/tratamiento farmacológico , Imagen por Resonancia Magnética/métodos , Sarcoidosis/diagnóstico , Sarcoidosis/tratamiento farmacológico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Estadística como Asunto , Resultado del TratamientoRESUMEN
In this report we present a patient with a recent diagnosis of cervical adenocarcinoma with progressive left lower extremity pain and weakness. MR imaging of the pelvis and subsequent FDG CT/PET were complementary in demonstrating abnormalities worrisome for perineural spread of malignancy, which was confirmed with an open fascicular biopsy of the sciatic nerve. We review the imaging and propose a mechanism of perineural spread to the sciatic nerve, which we believe is supported by the imaging in this case.
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Adenocarcinoma/patología , Fluorodesoxiglucosa F18 , Imagen Multimodal/métodos , Neoplasias del Sistema Nervioso Periférico/patología , Neuropatía Ciática/patología , Tomografía Computarizada por Rayos X/métodos , Neoplasias del Cuello Uterino/patología , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Radiofármacos , Enfermedades Raras/patologíaRESUMEN
Bone marrow is a ubiquitous component of musculoskeletal imaging studies. The ability to identify and characterize pathology accurately in the bone marrow can be challenging given the broad spectrum of imaging features of normal bone marrow. Knowledge regarding the ability to differentiate normal from abnormal marrow has been enhanced with MR imaging with numerous techniques available to aid in distinguishing benign from malignant lesions in the bone marrow. T1-weighted fast spin echo (FSE) and fluid-sensitive sequences, fat-saturated T2-weighted FSE, and short tau inversion recovery provide valuable tools for the evaluation of a focal bone marrow lesion. Gadolinium enhancement, chemical shift, diffusion-weighted, and MR spectroscopy imaging are additional tools available for focal bone marrow lesion evaluation. Whole-body MRI and fluorodeoxyglucose positron emission tomography-computed tomography have evolved to be useful studies for staging and monitoring of therapeutic response in whole-body imaging. The relative advantages and disadvantages of the whole-body techniques are reviewed for metastases, myeloma, and lymphoma.
Asunto(s)
Neoplasias de la Médula Ósea/diagnóstico , Médula Ósea/patología , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Gadolinio , Humanos , Aumento de la Imagen/métodos , Imagen de Cuerpo Entero/métodosRESUMEN
RATIONALE AND OBJECTIVES: The objective of our study was to determine if the T1-weighted magnetic resonance imaging (MRI) features associated with diabetic pedal osteomyelitis are present in histopathologically proven cases of non-pedal osteomyelitis. MATERIALS AND METHODS: Seventy-five patients with a histopathologically proven diagnosis of non-pedal osteomyelitis and a preoperative MRI were identified between 2000 and 2007. The MRIs were retrospectively reviewed for signal characterization of T1-weighted images, including the signal intensity compared with skeletal muscle, distribution of abnormal signal intensity, and pattern of abnormal signal intensity. A subsequent chart review was performed to identify potential clinical factors that were more associated with atypical T1 features of osteomyelitis. Fisher's exact test was performed to determine if there was a statistically significant difference in the T1-weighted imaging features of the hematogenous and nonhematogenous mechanisms of infection. RESULTS: Seventy of 75 cases demonstrated T1-weighted imaging features typical of pedal osteomyelitis with a confluent region of decreased signal intensity, hypointense, or isointense relative to skeletal muscle in a geographic pattern with medullary distribution. Of the 5 cases that did not demonstrate the typical T1 features associated with pedal osteomyelitis, 4 were considered to have a hematologic mechanism of infection given the absence of surgery, skin ulceration, or a penetrating injury. CONCLUSION: The majority of cases of non-pedal osteomyelitis in our study demonstrate the typical T1-weighted imaging features previously documented to correlate with the diagnosis of pedal osteomyelitis. The cases in our series that did not demonstrate the typical T1-weighted features were predominantly secondary to a hematologic mechanism of infection.
Asunto(s)
Imagen por Resonancia Magnética/métodos , Osteomielitis/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
The peroneocalcaneus internus (PCI) is a rare accessory muscle of the medial ankle with typical MRI anatomic features allowing differentiation from the more common accessory flexor digitorum longus muscle. To our knowledge, there have been no previously published sonographic images of the peroneocalcaneus internus. A PCI is typically an incidental, asymptomatic finding, but knowledge of the entity may avoid confusion when initially encountered by diagnostic ultrasound. We review the anatomic imaging features which allow for a confident imaging diagnosis and the clinical relevance of this anomaly.