FDG PET-CT evaluation in neurolymphomatosis: imaging characteristics and clinical outcomes

Abstract

Neurolymphomatosis (NL) often represents unidentified non-Hodgkin lymphoma relapses. Considering its severity, early detection and treatment are crucial. We outline one hospital's F-FDG-PET-CT imaging findings of NL, along with the patients' clinical characteristics. Clinical records and imaging findings of 19 NL patients, PET-CT diagnosed, were retrospectively reviewed. Patient data, FDG-PET-CT findings and the presence of coexisting diseases, especially CNS involvement, were documented. Available MRI and clinical data verified the findings. All cases had increased linear FDG uptake along anatomic nerve sites. CTs showed varying degrees of corresponding soft-tissue-thickening. Clinical correlations also contributed to the diagnosis. In 4/19 patients, lymphoma presented with NL, in 15/19 it appeared with disease recurrence/progression. In 9/19, clinical symptoms suggested neural involvement while 10/19 had nonspecific symptoms. Eleven died of lymphoma within 0.9 years of diagnosis despite directed-therapy. Eight, however, survived up to 7.82 years post-diagnosis. Whole-body FDG-PET-CT can assist in early NL diagnosis, possibly enhancing survival.

The utility of PET/CT in large vessel vasculitis

“…All available images were interpreted by experienced specialists in nuclear medicine and radiology, and re-reviewed by one of the study co-authors, who has dual certification in radiology and nuclear medicine with 20 years’ experience (TD). FDG uptake in the lesions was measured by standardized uptake values max (SUVmax), which were calculated by manually generating a region of interest over the sites of abnormally increased FDG activity 22 – 24 . Vasculitis was defined by identifying PET areas of increased uptake along the vessels.…”

“…The transaxial field of view and pixel size of the PET images reconstructed for fusion were 57.6 cm and 4 mm, respectively, with a matrix size of 144 × 144. The technical parameters used for CT imaging were: pitch 0.8, gantry rotation speed 0.5 s/rotation, 120 kVp, 250 mAs, 3 mm slice thickness, and specific breath-holding instructions 22 – 24 .…”

“…CT images were fused with the PET data and were used to generate a map for attenuation correction. PET images were reconstructed using a line of response protocol with CT attenuation correction, and the reconstructed images were generated for review on a computer workstation (Extended Brilliance Workstation, Philips Medical Systems, Cleveland OH, USA) 22 – 24 .…”

Penile secondary lesions: a rare entity detected by PET/CT

“…The CT component was performed in accordance with the hospital's standard protocol, with routine use of both oral and intravenous contrast media unless either was contraindicated. The following technical parameters were used for CT imaging: pitch 0.8, gantry rotation speed 0.5, 120 kVp, 250 mAs, 3-mm slice thickness, and specific breath-holding instructions [18][19][20] .…”

“…The diagnostic CT images were used for fusion with the PET data and to produce a map for attenuation correction. PET images were generated with CT attenuation correction utilizing a line of response protocol, and the reconstructed images were constructed for review (EWB, Extended Brilliance Workstation, Philips Medical Systems, Cleveland OH, USA) [18][19][20] .…”