학술논문
Long-term Follow-up and Histological Correlation of Peripheral Nervous System Alterations in Neurofibromatosis Type 2
Original Article
Original Article
Document Type
Clinical report
Author
Source
Clinical Neuroradiology. March 2022, Vol. 32 Issue 1, p277, 9 p.
Subject
Language
English
ISSN
1869-1439
Abstract
Author(s): Tim Godel [sup.1], Philipp Bäumer [sup.1] [sup.2], Said Farschtschi [sup.3], Klaus Püschel [sup.4], Barbara Hofstadler [sup.1], Sabine Heiland [sup.1], Mathias Gelderblom [sup.3], Martin Bendszus [sup.1], Christian Hagel [sup.5], Victor-Felix [...]
Purpose To examine long-term alterations of the dorsal root ganglia (DRG) and the peripheral nerve in patients with neurofibromatosis type 2 (NF2) by in vivo high-resolution magnetic resonance neurography (MRN) and their correlation to histology. Methods In this prospective study the lumbosacral DRG, the right sciatic, tibial, and peroneal nerves were examined in 6 patients diagnosed with NF2 and associated polyneuropathy (PNP) by a standardized MRN protocol at 3â¯T. Volumes of DRG L3-S2 as well as peripheral nerve lesions were assessed and compared to follow-up examinations after 14-100 months. In one patient, imaging findings were further correlated to histology. Results Follow-up MRN examination showed a non-significant increase of volume for the DRG L3: +0.41% (pâ¯= 0.10), L4: +22.41% (pâ¯= 0.23), L5: +3.38% (pâ¯= 0.09), S1: +10.63% (pâ¯= 0.05) and S2: +1.17% (pâ¯= 0.57). Likewise, peripheral nerve lesions were not significantly increased regarding size (2.18â¯mm.sup.2 vs. 2.15â¯mm.sup.2, pâ¯= 0.89) and number (9.00 vs. 9.33, pâ¯= 0.36). Histological analyses identified schwannomas as the major correlate of both DRG hyperplasia and peripheral nerve lesions. For peripheral nerve microlesions additionally clusters of onion-bulb formations were identified. Conclusion Peripheral nervous system alterations seem to be constant or show only a minor increase in adult NF2. Thus, symptoms of PNP may not primarily attributed to the initial schwannoma growth but to secondary long-term processes, with symptoms only occurring if a certain threshold is exceeded. Histology identified grouped areas of Schwann cell proliferations as the correlate of DRG hyperplasia, while for peripheral nerve lesions different patterns could be found.
Purpose To examine long-term alterations of the dorsal root ganglia (DRG) and the peripheral nerve in patients with neurofibromatosis type 2 (NF2) by in vivo high-resolution magnetic resonance neurography (MRN) and their correlation to histology. Methods In this prospective study the lumbosacral DRG, the right sciatic, tibial, and peroneal nerves were examined in 6 patients diagnosed with NF2 and associated polyneuropathy (PNP) by a standardized MRN protocol at 3â¯T. Volumes of DRG L3-S2 as well as peripheral nerve lesions were assessed and compared to follow-up examinations after 14-100 months. In one patient, imaging findings were further correlated to histology. Results Follow-up MRN examination showed a non-significant increase of volume for the DRG L3: +0.41% (pâ¯= 0.10), L4: +22.41% (pâ¯= 0.23), L5: +3.38% (pâ¯= 0.09), S1: +10.63% (pâ¯= 0.05) and S2: +1.17% (pâ¯= 0.57). Likewise, peripheral nerve lesions were not significantly increased regarding size (2.18â¯mm.sup.2 vs. 2.15â¯mm.sup.2, pâ¯= 0.89) and number (9.00 vs. 9.33, pâ¯= 0.36). Histological analyses identified schwannomas as the major correlate of both DRG hyperplasia and peripheral nerve lesions. For peripheral nerve microlesions additionally clusters of onion-bulb formations were identified. Conclusion Peripheral nervous system alterations seem to be constant or show only a minor increase in adult NF2. Thus, symptoms of PNP may not primarily attributed to the initial schwannoma growth but to secondary long-term processes, with symptoms only occurring if a certain threshold is exceeded. Histology identified grouped areas of Schwann cell proliferations as the correlate of DRG hyperplasia, while for peripheral nerve lesions different patterns could be found.