MRI Diagnosis of Obesity-Related Spinal Epidural Lipomatosis

Image-Guided Minimally Invasive Treatment Options for Degenerative Lumbar Spine Disease: A Practical Overview of Current Possibilities

Lumbar back pain is one of the main causes of disability around the world. Most patients will complain of back pain at least once in their lifetime. The degenerative spine is considered the main cause and is extremely common in the elderly population. Consequently, treatment-related costs are a major burden to the healthcare system in developed and undeveloped countries. After the failure of conservative treatments or to avoid daily chronic drug intake, invasive treatments should be suggested. In a world where many patients reject surgery and prefer minimally invasive procedures, interventional radiology is pivotal in pain management and could represent a bridge between medical therapy and surgical treatment. We herein report the different image-guided procedures that can be used to manage degenerative spine-related low back pain. Particularly, we will focus on indications, different techniques, and treatment outcomes reported in the literature. This literature review focuses on the different minimally invasive percutaneous treatments currently available, underlining the central role of radiologists having the capability to use high-end imaging technology for diagnosis and subsequent treatment, allowing a global approach, reducing unnecessary surgeries and prolonged pain-reliever drug intake with their consequent related complications, improving patients' quality of life, and reducing the economic burden.

Role of epidural fat in the local milieu: what we know and what we don't

PURPOSE

Traditionally, the epidural fat (EF) is known as a physical buffer for the dural sac against the force and a lubricant facilitating the relative motion of the latter on the osseous spine. Along with the development of the studies on EF, controversies still exist on vital questions, such as the underlying mechanism of the spinal epidural lipomatosis. Meanwhile, the scattered and fragmented researches hinder the global insight into the seemingly dispensable tissue.

METHODS

Herein, we reviewed literature on the EF and its derivatives to elucidate the dynamic change and complex function of EF in the local milieu, especially at the pathophysiological conditions. We start with an introduction to EF and the current pathogenic landscape, emphasizing the interlink between the EF and adjacent structures. We generally categorize the major pathological changes of the EF into hypertrophy, atrophy, and inflammation.

RESULTS AND CONCLUSIONS

It is acknowledged that not only the EF (or its cellular components) may be influenced by various endogenic/exogenic and focal/systematic stimuli, but the adjacent structures can also in turn be affected by the EF, which may be a hidden pathogenic clue for specific spinal disease. Meanwhile, the unrevealed sections, which are also the directions the future research, are proposed according to the objective result and rational inference. Further effort should be taken to reveal the underlying mechanism and develop novel therapeutic pathways for the relevant diseases.

Correlation of spinal epidural fat volume with body mass index: a longitudinal study

PURPOSE

Spinal epidural lipomatosis is abnormal accumulation of normal fat in the epidural space with weight loss suggested as first-line therapy in select symptomatic patients. However, moderate to large longitudinal studies establishing concordant changes between body mass index and epidural fat are lacking. The purpose of this study was to longitudinally assess this relationship.

METHODS

We performed an ancillary study of the Habitual Diet and Avocado Trial. Baseline and six-month abdominal MRIs were analyzed for 98 overweight or obese but otherwise healthy subjects. Dorsal epidural fat volumes in the lumbar spine were measured and correlated with changes in body mass index, changes in visceral fat volume, and demographic information.

RESULTS

There was a linear relationship between body mass index changes and epidural fat volume changes with a one-point change in body mass index corresponding to a 45 mm³ change in dorsal epidural fat volume (p < 0.001, 95% CI 31.87 to 76.77) as well as between visceral fat volume changes and epidural fat volume changes (regression coefficient 0.51, p < 0.001, 95% CI 0.22 to 0.47). Age was inversely related with subjects older than 45.7 years tending to lose epidural fat (regression coefficient -0.22, p = 0.025, 95% CI -10.43 to -0.72).

CONCLUSION

Changes in spinal dorsal epidural fat volume parallel changes in body mass index and visceral fat, supporting weight loss as initial treatment for uncomplicated obesity-associated spinal epidural lipomatosis.

Could Spinal Epidural Lipomatosis Be the Hallmark of Metabolic Syndrome on the Spine? A Literature Review with Emphasis on Etiology

Spinal epidural lipomatosis is defined by an excessive amount of epidural fat in the spinal canal, usually in the lumbosacral tract: a well-known cause of lumbar pain and spinal stenosis with a possible wide range of neurological symptoms. Recent research data reveal that, nowadays, obesity has become the main cause of spinal epidural lipomatosis. Moreover, this condition was recently recognized as a previously unknown manifestation of metabolic syndrome. Radiological studies (CT and MRI) are the only tools that are able to diagnose the disease non-invasively. Indeed, radiologists play a key role in disease recognition, with subsequent possible implications on patients' systemic health assessments. Despite its clinical importance, the condition is still underreported and neglected. The current literature review summarizes all the main etiologies of spinal epidural lipomatosis, particularly regarding its linkage with metabolic syndrome. An overview of disease characteristics from diagnosis to treatment strategies is also provided.

Extensive Symptomatic Thoracolumbar Epidural Lipomatosis Treated With Minimally Invasive Hemilaminectomies: Technical Case Report

BACKGROUND AND IMPORTANCE

Spinal epidural lipomatosis is a rare condition commonly associated with chronic corticosteroid use and obesity that involves deposition of adipose tissue in the epidural space of the spinal canal. This accumulation of adipose tissue may cause compression of the spinal cord and/or nerve roots and result in compressive symptoms such as myelopathy or radiculopathy. Spinal involvement is usually confined to either the thoracic or lumbar spine but can infrequently affect both regions. Depending on pre-existing conditions, treatment options include weight loss and discontinuation of exogenous steroid use, both of which have been shown to be effective therapeutic methods. Surgical decompression may be useful for appropriately selected patients in whom conservative therapy has failed or who experience acute neurological deterioration, although this is rarely indicated.

CLINICAL PRESENTATION

In this study, we describe a patient receiving long-term corticosteroid therapy who presented with symptomatic epidural lipomatosis that involved the thoracic and lumbar spine. She was treated with decompression by continuous T3-L5 hemilaminectomies performed through 5 small incisions of alternating laterality. After surgery, the patient experienced clinical improvement and was able to return to her baseline.

CONCLUSION

We illustrate a successful spinal decompression of extensive epidural lipomatosis through a less-invasive surgical approach using several small incisions to accomplish uninterrupted hemilaminectomies. This alternative approach to a standard continuous incision can be considered in cases of extensive spinal epidural lipomatosis in patients with multiple medical comorbidities in whom wound healing is believed to be an issue and for whom minimizing blood loss is crucial.

Surgical management of thoracic myelopathy from long-segment epidural lipomatosis with skip hemilaminotomies: illustrative case

BACKGROUND

Thoracic spinal epidural lipomatosis (SEL) involves the pathological overgrowth of histologically normal, unencapsulated adipose tissue that can compress the spinal cord and cause myelopathy. SEL has been associated with multiple medical conditions, including Scheuermann kyphosis (SK). Optimal treatment strategies for SEL, especially in the setting of a sagittal spinal deformity, remain unclear.

OBSERVATIONS

In this report, the authors discussed surgical management of a patient with thoracic SEL and SK using skip hemilaminotomies for resection of the epidural adipose tissue. To the authors’ knowledge, only one other report described a similar surgical technique in a patient who did not have a spinal deformity.

LESSONS

When conservative efforts fail, thoracic SEL may require surgical treatment. Surgical planning must account for co-medical conditions such as SK. The described approach involving skip laminotomies, which minimizes spine destabilization, is a viable option to treat SEL spanning multiple spinal segments. Prognosis after surgical treatment varies and is impacted by multiple factors, including severity of preoperative neurological deficits.

MRI Features and Clinical Significance of Spinal Epidural Lipomatosis: All You Should Know

Spinal epidural lipomatosis (SEL) is defined as the abnormal accumulation of unencapsulated adipose tissue in the spinal epidural space. SEL can be asymptomatic or can cause a wide range of symptoms, the most common of which is neurogenic claudication. Several other neurological manifestations may also occur, above all myelopathy and radicular symptoms. The spinal level most frequently involved in patients with SEL is the lumbar one, followed by the thoracic one. Imaging plays a key role in disease assessment. MRI is considered the most effective and sensitive modality for diagnosing and staging SEL. Anyway, also CT scan can diagnose SEL. The diagnosis may be incidental (in mild-moderate disease) or may be taken into account in cases with neurological symptoms (in moderate-severe disease). There are some recognized risk factors for SEL, the most common of which are exogenous steroid use and obesity. Recent studies have found an association between SEL and obesity, hyperlipidemia and liver fat deposition. As a matter of fact, SEL can be considered the spinal hallmark of metabolic syndrome. Risk factors control represents the initial treatment strategy in patients with SEL (e.g. weight loss, steroid therapy suspension). Surgical decompression may be required when conservative treatment fails or when the patient develops acute/severe neurological symptoms.

Application of Magnetic Resonance Imaging in the Evaluation of Nutritional Status: A Literature Review with Focus on Dialysis Patients

Magnetic resonance imaging (MRI) is indispensable in clinical medicine for the morphological and tomographic evaluation of many parenchymal organs. With varied imaging methods, diverse biological information, such as the perfusion volume and measurements of metabolic products, can be obtained. In addition to conventional MRI for morphological assessment, diffusion-weighted MRI/diffusion tensor imaging is used to evaluate white matter structures in the brain; arterial spin labeling is used for cerebral blood flow evaluation; magnetic resonance elastography for fatty liver and cirrhosis evaluation; magnetic resonance spectroscopy for evaluation of metabolites in specific regions of the brain; and blood oxygenation level-dependent imaging for neurological exploration of eating behavior, obesity, and food perception. This range of applications will continue to expand in the future. Nutritional science is a multidisciplinary and all-inclusive field of research; therefore, there are many different applications of MRI. We present a literature review of MRI techniques that can be used to evaluate the nutritional status, particularly in patients on dialysis. We used MEDLINE as the information source, conducted a keyword search in PubMed, and found that, as a nutritional evaluation method, MRI has been used frequently to comprehensively and quantitatively evaluate muscle mass for the determination of body composition.