7 research outputs found
Extended Retrosigmoid Craniotomy and Clip Occlusion of a Petrosal Tentorial Dural Arteriovenous Fistula (Type 5): Operative Video
Univ Calif San Francisco, Dept Neurosurg, San Francisco, CA 94143 USAUniv Fed Sao Paulo, Dept Neurocirurgia Vasc, Sao Paulo, BrazilUniv Fed Fluminense, Fac Med, Niteroi, RJ, BrazilUniv Calif San Francisco, Ctr Cerebrovasc Res, San Francisco, CA 94143 USAUniv Fed Sao Paulo, Dept Neurocirurgia Vasc, Sao Paulo, BrazilWeb of Scienc
"Million dollar nerve” magnetic resonance neurography: first normal and pathological findings
Objectives: To evaluate prospectively the feasibility of magnetic resonance neurography (MRN) in identifying the anatomical characteristics of thenar muscular branch (TMB) of the median nerve, also known as the “million dollar nerve”, in patients and controls. Methods: Thirteen patients affected by carpal tunnel syndrome (CTS) and four healthy controls had their hands scanned on a 3T MR imaging scanner for TMB visualization. Median nerve anatomical variations were classified into four groups according to the Poisel’s classification system modified by Lanz. TMB signal intensity and diameter were assessed for the diagnosis of neuropathy. Results: TMB was successfully identified in all patients and subjects by using MRN. The most suitable pulse sequences to identify and measure nerve diameter were 3D DW-PSIF and T2-FS-TSE. The axial oblique and sagittal oblique planes are complementary in demonstrating its entire course. TMB had mostly an extraligamentous course with radial side origin (93.8%, each). All patients experienced increased T2 signal intensity (P < 0.001) and thickened nerves. Mean TMB diameters were 1.27 ± 0.21 mm (range, 1.02–1.74 mm) and 0.87 ± 0.16 mm (0.73–1.08 mm) (P = 0.008) in the patient and control groups, respectively. Conclusion: MRN is a reliable imaging technique for identification and anatomical characterization of TMB in patients affected by CTS. This innovative imaging workup may therefore be included in the preoperative evaluation of patients scheduled for carpal tunnel release, especially in CTS with TMB involvement or even in isolated TMB neuropathySimObjectives: To evaluate prospectively the feasibility of magnetic resonance
neurography (MRN) in identifying the anatomical characteristics of thenar
muscular branch (TMB) of the median nerve, also known as the “million dollar
nerve”, in patients and controls.
Methods: Thirteen patients affected by carpal tunnel syndrome (CTS) and four
healthy controls had their hands scanned on a 3T MR imaging scanner for TMB
visualization. Median nerve anatomical variations were classified into four groups
according to the Poisel’s classification system modified by Lanz. TMB signal
intensity and diameter were assessed for the diagnosis of neuropathy.
Results: TMB was successfully identified in all patients and subjects by using
MRN. The most suitable pulse sequences to identify and measure nerve diameter
were 3D DW-PSIF and T2-FS-TSE. The axial oblique and sagittal oblique planes
are complementary in demonstrating its entire course. TMB had mostly an
extraligamentous course with radial side origin (93.8%, each). All patients
experienced increased T2 signal intensity (P < 0.001) and thickened nerves.
Mean TMB diameters were 1.27 ± 0.21 mm (range, 1.02–1.74 mm) and 0.87 ±
0.16 mm (0.73–1.08 mm) (P = 0.008) in the patient and control groups,
respectively.
Conclusion: MRN is a reliable imaging technique for identification and
anatomical characterization of TMB in patients affected by CTS. This innovative
imaging workup may therefore be included in the preoperative evaluation of patients scheduled for carpal tunnel release, especially in CTS with TMB
involvement or even in isolated TMB neuropathy