[Spinal epidural lipomatosis]

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.

Comparison of relative and absolute values of magnetic resonance imaging in the diagnosis of spinal epidural lipomatosis

OBJECTIVE

To describe spinal epidural lipomatosis (SEL) of the lumbar region and evaluate the relative versus absolute values of epidural fat (EF) to determine which is more appropriate when using magnetic resonance imaging (MRI).

DESIGN

Comparative study.

SETTING

Hospital.

PARTICIPANTS

Eight SEL patients and 40 healthy adults.

INTERVENTIONS

MRI measurement of EF.

OUTCOME MEASURES

The MRI-based EF thickness, cutoff value, and coefficient of variation (CV) were calculated. Frequency distribution maps for the absolute EF value and the relative EF/DuS value were created.

RESULTS

SEL involved L3 - L4 in all cases. The mean EF thickness was 12.11 ± 2.28 mm (range: 9.91 - 16.86 mm), and the average diameter of the dural sac (DuS) was 20.02 ± 2.64 mm; the EF/DuS ratio was 0.61 ± 0.03. In controls, the average EF thickness was 7.35 ± 1.68 mm (range: 4.81 - 10.92 mm), and the average DuS was 20.86 ± 2.11 mm; the EF/DuS ratio was 0.35 ± 0.08. The relative and absolute values were significantly higher in the SEL group than in the normal group. A cutoff value of 9.8 mm could distinguish SEL patients from normal individuals. For the SEL group, the CV of the relative values (4.9%) was lower than that of the absolute values (18.8%). The frequency distribution map showed that the distribution of relative values was more concentrated than that of the absolute values for both groups.

CONCLUSION

Based on the frequency distribution and CVs, the relative value of EF/DuS maybe a better measure for diagnosing SEL than the absolute EF value.

[Spinal epidural lipomatosis as a rare side effect in steroid-dependent Jo-1 antibody syndrome]

Spinal epidural lipomatosis (SEL) of the thoracic and lumbar spine is a rare entity, which leads to compression of the spinal canal. The exact pathogenesis is still unknown. It most commonly occurs in patients with long-term exogenous or endogenous glucocorticoid excess or morbid obesity but there are also idiopathic forms. The symptoms depend on the severity of the SEL and can manifest as clinically asymptomatic, non-specific back pain, radiculopathy up to spinal cord compression. The diagnosis is usually achieved by magnetic resonance imaging (MRI) of the affected spinal segments. The treatment varies between discontinuation of glucocorticoids, weight reduction up to multisegmental decompressive laminectomy. The following case report presents the findings of SEL in a patient with steroid-dependent Jo-1 antibody syndrome and provides a current literature review on this rare disease.