Basic Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. May 28, 2017; 9(5): 230-244
Published online May 28, 2017. doi: 10.4329/wjr.v9.i5.230
Cystic lesions of peripheral nerves: Are we missing the diagnosis of the intraneural ganglion cyst?
Jyoti Panwar, Anil Mathew, Binu P Thomas
Jyoti Panwar, Department of Radiology, Christian Medical College, Vellore 632004, India
Jyoti Panwar, Joint Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario M5G 2N2, Canada
Anil Mathew, Binu P Thomas, Department of Hand Surgery and Leprosy Reconstructive Surgery, Christian Medical College, Vellore 632004, India
Author contributions: Panwar J and Mathew A participated in the conception, acquisition, analysis, interpretation of the data and drafted the initial manuscript; Panwar J was the guarantor and designed the study; Thomas BP revised the article critically for important intellectual content; language revision and final approval of the version of the article was done by Mathew A and Thomas BP.
Institutional review board statement: The study was reviewed and approved by the Institutional review board, Christian Medical College, Vellore, India.
Informed consent statement: Not applicable given the retrospective design of our study.
Conflict-of-interest statement: There are no conflicts of interest to report.
Data sharing statement: No additional data is available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jyoti Panwar, MD, FRCR, Musculoskeletal Radiology Fellow, Joint Department of Medical Imaging, University Health Network, University of Toronto, 585 University Avenue, Toronto, Ontario M5G 2N2, Canada. drjyoticmch@gmail.com
Telephone: +1-416-3403372
Received: September 26, 2016
Peer-review started: September 28, 2016
First decision: October 20, 2016
Revised: January 17, 2017
Accepted: March 16, 2017
Article in press: March 17, 2017
Published online: May 28, 2017
Abstract
AIM

To highlight the salient magnetic resonance imaging (MRI) features of the intraneural ganglion cyst (INGC) of various peripheral nerves for their precise diagnosis and to differentiate them from other intra and extra-neural cystic lesions.

METHODS

A retrospective analysis of the magnetic resonance (MR) images of a cohort of 245 patients presenting with nerve palsy involving different peripheral nerves was done. MR images were analyzed for the presence of a nerve lesion, and if found, it was further characterized as solid or cystic. The serial axial, coronal and sagittal MR images of the lesions diagnosed as INGC were studied for their pattern and the anatomical extent along the course of the affected nerve and its branches. Its relation to identifiable anatomical landmarks, intra-articular communication and presence of denervation changes in the muscles supplied by involved nerve was also studied.

RESULTS

A total of 45 cystic lesions in the intra or extraneural locations of the nerves were identified from the 245 MR scans done for patients presenting with nerve palsy. Out of these 45 cystic lesions, 13 were diagnosed to have INGC of a peripheral nerve on MRI. The other cystic lesions included extraneural ganglion cyst, paralabral cyst impinging upon the suprascapular nerve, cystic schwannoma and nerve abscesses related to Hansen’s disease involving various peripheral nerves. Thirteen lesions of INGC were identified in 12 patients. Seven of these affected the common peroneal nerve with one patient having a bilateral involvement. Two lesions each were noted in the tibial and suprascapular nerves, and one each in the obturator and proximal sciatic nerve. An intra-articular connection along the articular branch was demonstrated in 12 out of 13 lesions. Varying stages of denervation atrophy of the supplied muscles of the affected nerves were seen in 7 cases. Out of these 13 lesions in 12 patients, 6 underwent surgery.

CONCLUSION

INGC is an important cause of reversible mono-neuropathy if diagnosed early and surgically treated. Its classic MRI pattern differentiates it from other lesions of the peripheral nerve and aid in its therapeutic planning. In each case, the joint connection has to be identified preoperatively, and the same should be excised during surgery to prevent further cyst recurrence.

Keywords: Intra-neural, Magnetic resonance imaging, Peripheral nerves, Extra-neural, Ganglion cyst

Core tip: This is a retrospective study to emphasize the characteristic magnetic resonance imaging (MRI) features of the intraneural ganglion cyst (INGC) of the peripheral nerves. The radiologist should recognize the classic MRI pattern of the INGC, its joint connection and imaging anatomy of the involved nerve. This would aid surgeons in complete removal of the cyst, prevent its recurrence and hence improved patient outcomes. Both radiologists and surgeons should be aware of other neurogenic lesions and the extra neural ganglion cyst which may also have a joint connection.