An unusual case of footdrop: anterior disc herniation mimicking a nerve sheath tumor

Extreme lateral disc herniations are described. Usually, the herniated disc is described as being at the lateral edge of the neural foramen. Herniated discs that lodge beyond this location need to be included in the differential of retroperitoneal lesions impinging on nerve roots. A 76-year-old woman presented with left leg radicular symptoms, including footdrop and a retroperitoneal lesion. Given the location of the lesion and its distance from the edge of the neural foramen, the differential diagnosis favored a nerve sheath tumor. An anterior retroperitoneal approach was taken. At the time of surgery, the lesion proved to be a herniated disc arising from the anterior surface of the L5-S1 disc space, medial to the psoas muscle. The disc herniation resulted in severe compression of the L5 nerve root as the root joined the lumbosacral plexus. This type of even more extreme lateral disc herniation is not widely reported. At this location, there are reports of clinicians confusing discs for tumors and occasionally tumors for discs. Given that some disc herniations are no longer visually adjacent to the foramen, perhaps extreme lateral disc herniation is not an ideal term. This individual case report is supplemented with a review of the literature on this rare condition with specific searches for disc, retroperitoneal, anterior herniation. Using the term anterior disc herniation will aid clinicians in including herniated disc fragments in the differential diagnosis for lesions affecting nerve roots anterior to the spine in this retroperitoneal location

Albumin Therapy Improves Local Vascular Dynamics in a Rat Model of Primary Microvascular Thrombosis : A Two-Photon Laser-Scanning Microscopy Study

BACKGROUND AND PURPOSE: High-dose human albumin is robustly neuroprotective in preclinical ischemia models and is currently in phase III clinical trial for acute ischemic stroke. To explore the hypothesis that albumin’s protective effect is mediated in part by salutary intravascular mechanisms, we assessed microvascular hemodynamics in a model of laser-induced cortical arteriolar thrombosis. METHODS: The cortical microcirculation of anesthetized, physiologically monitored Sprague-Dawley rats was studied in vivo via a frontoparietal cranial window (intact dura) by two-photon laser-scanning microscopy after plasma-labeling with fluorescein-dextran. Focal thrombosis was produced in 30- to 50-µm cortical arterioles by laser irradiation. Arteriolar flow velocity was measured repeatedly by line-scanning. At 30 minutes post-thrombosis, animals were treated with either human albumin, 2 g/kg, or with saline control. RESULTS: Baseline arteriolar flow velocity averaged 3.5 ± 1.8 mm/s and was reduced to 10% to 13% of control values by laser-induced thrombosis, which also led to focal vasodilatation (mean, 49% above baseline diameter). Saline treatment at 30 minutes post-thrombosis failed to influence arteriolar flow velocity, which remained depressed at 10% to 22% of control throughout the subsequent 60- to 90-minute observation period. By contrast, albumin treatment induced a prompt rise in median flow velocity to 38% of control by 10 minutes post-treatment, and to 61% to 67% of control by 50 to 60 minutes. CONCLUSIONS: High-dose albumin therapy induces a prompt, sustained improvement in microvascular hemodynamics distal to a cortical arteriolar thrombosis; these data support an important intravascular component to albumin’s protective effect in acute cerebral ischemia

Albumin Therapy Augments the Effect of Thrombolysis on Local Vascular Dynamics in a Rat Model of Arteriolar Thrombosis : A Two-Photon Laser-Scanning Microscopy Study

BACKGROUND AND PURPOSE: Results of our recent pilot clinical trial suggest that the efficacy of thrombolytic therapy in acute ischemic stroke may be enhanced by the coadministration of high-dose albumin. Here, we explored the microvascular hemodynamic effects of this combined therapy in a laboratory model of cortical arteriolar thrombosis. METHODS: We studied the cortical microcirculation of physiologically monitored rats in vivo by two-photon laser-scanning microscopy after plasma-labeling with fluorescein-dextran. We induced focal thrombosis in 30- to 50-µm cortical arterioles by laser irradiation and measured arteriolar flow velocity by repeated line-scanning. At 30 minutes post-thrombosis, we treated animals with the thrombolytic agent, reteplase, which was coadministered with either human albumin, 2 g/kg, or with saline control. RESULTS: Baseline arteriolar flow velocity averaged 3.8±0.7 mm/s, was immediately reduced by thrombosis to 22% to 25% of control values, and remained unchanged before treatment. Subthrombolytic doses of reteplase combined with saline led to a median increase in flow velocity to 37% of control distal to the thrombus (P=nonsignificant versus pretreatment). By contrast, reteplase combined with albumin therapy resulted in a prompt, highly significant increase of median flow velocity to 58% of control levels (P=0.013 versus reteplase+saline), which remained significantly higher than the reteplase+saline group at multiple time-points over the subsequent hour. CONCLUSIONS: The beneficial effect of subthrombolytic doses of reteplase on microvascular hemodynamics distal to a cortical arteriolar thrombosis is markedly enhanced by the coadministration of high-dose albumin therapy; these results have important clinical implications for the management of patients with acute ischemic stroke