Correction to: Disc inflammation and Modic changes show an interaction effect on recovery after surgery for lumbar disc herniation.

In Tables 3 and 4: In the first column and row, the text reads "Mixed model test (patients with Modic changes)". This should have been just "Mixed model". The complete correct Tables 3 and 4 are given below.

Disc inflammation and Modic changes show an interaction effect on recovery after surgery for lumbar disc herniation.

PURPOSE: To study the interaction between Modic changes (MC) and inflammation by macrophages in the disc, in relation to clinical symptoms before and after discectomy for lumbar disc herniation. METHODS: Disc tissue was embedded in paraffin and stained with haematoxylin and CD68. Subsequently, tissue samples were categorized for degree of inflammation. Type of MC was scored on MRI at baseline. Roland Disability Questionnaire (RDQ) score and visual analogue scale for back pain and leg pain separately were considered at baseline and 1-year follow-up post-surgery. Main and interaction effects of MC and inflammation were tested against clinical outcome questionnaires. In addition, this analysis was repeated in bulging and extruded discs separately. RESULTS: Disc material and MRI's of 119 patients were retrieved and analysed. Forty-eight patients demonstrated mild inflammation, 45 showed moderate inflammation, and 26 showed considerable inflammation. In total, 49 out of 119 patients demonstrated MC. Grade of disc inflammation did not associate with the presence of MC. At baseline, no main or interaction effects of MC and inflammation were found on the clinical scores. However, during follow-up after discectomy, significant interaction effects were found for RDQ score: Only in patients with MC at baseline, patients remained significantly more disabled (3.2 points p = 0.006) if they showed considerable disc inflammation compared to patients with mild inflammation. The additional analysis showed similar results in extruded discs, but no significant effects in bulging discs. CONCLUSIONS: An interaction effect of MC and disc inflammation by macrophages is present. Only in patients with MC, those with considerable inflammation recover less satisfactory during follow-up after surgery. These slides can be retrieved under Electronic Supplementary Material.

Thoracic epidural haematoma due to a subclavian steal syndrome and secondary formed thoracic collateral circuits, coincidence or consequence: a case report.

Despite profound diagnostics, the aetiology of spinal epidural haematoma (SEH) often remains unknown. In this case, diagnostics revealed an SEH at the fifth and sixth thoracic levels due to a subclavian steal syndrome with a tortuous vascular loop between the sixth thoracic intercostal artery and the costocervical arteries deriving from the left subclavian artery with plump arteries in the epidural space. The patient underwent decompression surgery and a percutaneous transluminal angioplasty. The patient showed good recovery at follow-up. The SEH was a result of secondary formed thoracic collateral circuits with epidural involvement due to a subclavian steal syndrome.

Gadolinium Enhancement Is Not Associated With Disc Inflammation in Patients With Sciatica.

STUDY DESIGN: Retrospective observational histological study. OBJECTIVE: To evaluate the reliability of gadolinium enhancement as a marker for inflammation by associating gadolinium enhancement findings with the degree of inflammation as measured by macrophage infiltration in disc material retrieved during disc surgery in patients with sciatica. SUMMARY OF BACKGROUND DATA: Disc inflammation often occurs in sciatica patients, a noninvasive tool that is used to assess disc inflammation is Gadolinium enhanced MR imaging. METHODS: Disc tissue was retrieved from patients in the Sciatica trial (N = 119), a multicenter randomized controlled trial in patients with sciatica. Disc tissue was embedded in paraffin and stained with hematoxylin and CD68. Tissue samples were categorized as mild (0-10 macrophages/cm), moderate (10-100 macrophages/cm), and considerable (>100 macrophages/cm) inflammation. Of the 119 MRIs, 96 were additionally performed with contrast-enhanced gadolinium. RESULTS: Seventy-four patients showed gadolinium enhancement of the disc herniation and 26 of the nerve root. Degree of inflammation by macrophages was not associated with gadolinium enhancement of nerve roots or herniated discs. These results did not change if the patient groups with and without Modic type 2 changes were evaluated separately. Furthermore, no associations were observed between gadolinium enhancement and presence of Modic type 2 changes. CONCLUSION: This study found gadolinium enhanced MRI findings to be unreliable as an indicator for inflammation of disc herniation or nerve root in patients with sciatica. LEVEL OF EVIDENCE: 2.

Simultaneous measurements of cerebral oxygenation changes during brain activation by near-infrared spectroscopy and functional magnetic resonance imaging in healthy young and elderly subjects.

Near infrared spectroscopy (NIRS) and functional magnetic resonance imaging (fMRI) both allow non-invasive monitoring of cerebral cortical oxygenation responses to various stimuli. To compare these methods in elderly subjects and to determine the effect of age on cortical oxygenation responses, we determined motor-task-related changes in deoxyhemoglobin concentration ([HHb]) over the left motor cortex in six healthy young subjects (age 35 +/- 9 years, mean +/- SD) and five healthy elderly subjects (age 73 +/- 3 years) by NIRS and blood-oxygen-level-dependent (BOLD) fMRI simultaneously. The motor-task consisted of seven cycles of 20-sec periods of contralateral finger-tapping at a rate as fast as possible alternated with 40-sec periods of rest. Time-locked averages over the seven cycles were used for further analysis. Task-related decreases in [HHb] over the motor cortex were measured by NIRS, with maximum changes of -0.83 +/- 0.38 mumol/L (P < 0.01) for the young and -0.32 +/- 0.17 mumol/L (P < 0.05) for the elderly subjects. The BOLD-fMRI signal increased over the cortex volume under investigation with NIRS, with maximum changes of 2.11 +/- 0.72% (P < 0.01) for the young and 1.75 +/- 0.71% (P < 0.01) for the elderly subjects. NIRS and BOLD-fMRI measurements showed good correlation in the young (r = -0.70, r(2) = 0.48, P < 0.001) and elderly subjects (r = -0.82, r(2) = 0.67, P < 0.001). Additionally, NIRS measurements demonstrated age-dependent decreases in task-related cerebral oxygenation responses (P < 0.05), whereas fMRI measurements demonstrated smaller areas of cortical activation in the elderly subjects (P < 0.05). These findings demonstrate that NIRS and fMRI similarly assess cortical oxygenation changes in young subjects and also in elderly subjects. In addition, cortical oxygenation responses to brain activation alter with aging.