Median intraneural ganglion cyst at the elbow: the first known example of a joint connection and a reflection on the past. Illustrative case.

Background: The articular origin of intraneural ganglion cysts has been previously described and well supported, except for the median nerve at the level of the elbow.

Observations: The authors present a patient with a median intraneural ganglion cyst at the elbow region and magnetic resonance imaging (MRI) evidence of a joint connection to the proximal radioulnar joint. A 63-year-old man presented with thumb flexion weakness and dysesthesias in the thumb, index, and middle fingers.

Induction of Extremely Severe Nausea via Vestibular Activation on a 7 Tesla MRI Scanner.

Extremely severe nausea was experienced by four subjects positioned prone on a 7T scanner table with their arm extended overhead for a wrist examination and their head positioned approximately 10-20 cm above the magnet's central axis. Movement through the large static and spatial field gradients of current 7T MRI scanner magnets typically causes mild vestibular activation which is well tolerated by most individuals. However, when positioned off-axis, the head moves through regions of even larger and more rapidly changing magnetic fields which in the current study were sufficient to induce the extremely severe nausea.

Development of a tibial intraneural ganglion cyst after surgery on a peroneal intraneural ganglion in a pediatric patient: further support for the articular origin of intraneural ganglion cysts. Illustrative case.

Background: The articular origin of intraneural cysts has been previously described and well supported. Intraneural ganglion cysts most commonly occur in adults and in the common peroneal nerve arising from the anterior aspect of the superior tibiofibular joint (STFJ).

Observations: The authors report a pediatric patient who developed a tibial intraneural cyst arising from the posterior aspect of the STFJ within months after surgical treatment of a peroneal intraneural cyst from the anterior aspect of the same joint.

Abnormal Brachial Plexus Differentiation from Routine Magnetic Resonance Imaging: An AI-based Approach.

Automatic abnormality identification of brachial plexus (BP) from normal magnetic resonance imaging to localize and identify a neurologic injury in clinical practice (MRI) is still a novel topic in brachial plexopathy. This study developed and evaluated an approach to differentiate abnormal BP with artificial intelligence (AI) over three commonly used MRI sequences, i.e.

Dynamic Computed Tomography of the Distal Radioulnar Joint Versus Magnetic Resonance Imaging in Detecting Foveal Tears of the Triangular Fibrocartilage Complex.

Background: Diagnosis of foveal triangular fibrocartilage complex (TFCC) tears remains difficult. The purpose of this study was to evaluate whether dynamic computed tomography (CT) of the distal radioulnar joint (DRUJ) has a higher sensitivity in detecting foveal tears of the TFCC when compared with magnetic resonance imaging (MRI).

Methods: A database query identified all patients above the age of 18 years with suspected foveal TFCC injuries who underwent bilateral dynamic CT imaging of the DRUJ, static 3T MRI, and subsequent wrist arthroscopy.

Exuberant circumferential fibroproliferative neuromas in lipomatosis of nerve: a unifying theory. Illustrative case.

Background: Lipomatosis of nerve (LN) is a rare disorder characterized by the massive enlargement of peripheral nerves, frequently accompanied by generalized fibroadipose proliferation and skeletal overgrowth.

Observations: The authors have been routinely following a 20-year-old male for lipomatosis of median nerve at the wrist noted shortly after birth. He had undergone resection of the lesion accompanied by sural nerve grafting at another institution.

Tibial intraneural ganglion cysts arising from the tibiofemoral joint: illustrative cases.

Background: Intraneural cysts involving the tibial nerve in the knee region (popliteal fossa) are rare. According to the articular (synovial) theory, which posits a joint origin for this pathology, these cysts originate from either the superior tibiofibular joint (STFJ) or the tibiofemoral (knee) joint. As tibial intraneural cysts arising from the tibiofemoral joint remain poorly understood, the authors present 2 illustrative cases and a review of the world's literature on all tibial intraneural ganglion cysts in the knee region.

7T for clinical imaging of benign peripheral nerve tumors: preliminary results.

Purpose: MRI has become an essential diagnostic imaging modality for peripheral nerve pathology. Early MR imaging for peripheral nerve depended on inferred nerve involvement by visualizing downstream effects such as denervation muscular atrophy; improvements in MRI technology have made possible direct visualization of the nerves. In this paper, we share our early clinical experience with 7T for benign neurogenic tumors.

Imaging Peripheral Nerve Injuries of the Lower Extremities: What Surgeons Need to Know.

Peripheral nerve injury is a common sequela of lower extremity trauma. Injuries to lower extremity nerves range from contusions and stretch injuries that will often resolve without interventions to traumatic disruptions requiring surgical procedures, including neurolysis, repair or even nerve grafting. While clinical examination and tools such as electromyography will often help to localize the site of injury, imaging is a critical tool in determining the extent and degree of nerve injury in the setting of trauma.

Posterior interosseous nerve paralysis secondary to an extraneural ganglion cyst from a radial neck pseudarthrosis: illustrative case.

Background: Many benign and malignant tissue or bony lesions have been reported as causes of extrinsic or intrinsic posterior interosseous nerve (PIN) neuropathy at the proximal forearm/elbow region. The authors describe an unusual cause of external compression of the PIN due to a ganglion cyst arising from a radial neck pseudarthrosis (a false joint).

Observations: Decompression of the PIN with the release of the arcade of Frohse was performed with resection of the radial head and the ganglion cyst.

Characterizing peroneal nerve injury clinicoradiological patterns with MRI in patients with sciatic neuropathy and foot drop after total hip replacement.

Objective: Sciatic nerve injury following total hip arthroplasty (THA) predominantly affects the peroneal division of the sciatic nerve, often causing a foot drop. This can result from a focal etiology (hardware malposition, prominent screw, or postoperative hematoma) or nonfocal/traction injury. The objective of this study was to compare the clinicoradiological features and define the extent of nerve injury resulting from these two distinct mechanisms.

Tibial intraneural ganglion cysts at the superior tibiofibular joint treated with joint resection alone: a proof of concept.

Background: Intraneural ganglion cysts involving the tibial nerve are rare. Recent evidence has supported an articular (synovial) theory to explain the joint-related origin of these cysts; however, optimal operative treatment for cysts originating from the STFJ remains poorly understood. Therefore, we present a novel strategy: addressing the joint itself without addressing the articular branch and/or the cyst.

Nerve relationships to the sacrospinous ligament: application to suspension procedures and transgluteal approaches for nerve repair and tumor removal with three case illustrations.

Background: Transvaginal suspension procedures often use the sacrospinous ligament (SSL), which attaches onto the ischial spine (IS). However, nerve-related sequelae (e.g.

Perineurioma of the sciatic nerve with reticular, microcystic, and pseudolipoblastic features: illustrative case.

Background: Perineuriomas are peripheral nerve sheath tumors that are composed of benign, localized proliferations of perineural cells and further subclassified as intraneural or extraneural (soft tissue) based on their relationship to the histological boundaries of the nerve. Multiple histological variants have been described, and herein the authors present the first known case of a pseudolipoblastic perineurioma affecting the nerve.

Observations: A 52-year-old woman presented with a 5-year history of progressive, severe left buttock pain radiating down to the top of her foot and ankle, without any associated weakness, with a large mass in her sciatic nerve noted on magnetic resonance imaging (MRI).

PET imaging characteristics of neuromuscular choristoma and associated desmoid-type fibromatosis.

Background: Neuromuscular choristoma (NMC) is a rare peripheral nerve lesion characterized by abnormal presence of muscle within nerve. Associated desmoid-type fibromatosis (NMC-DTF) often develops. We report F-fluorodeoxyglucose positron emission tomography (FDG PET) characteristics of NMC and NMC-DTF and propose that increased FDG activity within NMCs may be associated with subclinical NMC-DTF or NMC-DTF "precursor" tissue.

Peroneal intraneural ganglion cyst with a nearly invisible joint connection (even to advocates of the articular theory): illustrative case.

Background: The articular (synovial) theory describes the formation of intraneural ganglion cysts through defects in the capsule of synovial joints. While the articular theory is gaining significant traction in the literature, it is not universally accepted. Therefore, the authors present a case of a plainly visible peroneal intraneural cyst, although the subtle joint connection was not identified specifically at the time of surgery, with subsequent rapid extraneural cyst recurrence.

Occult lipomatosis of the nerve as part of macrodystrophia lipomatosa: illustrative case.

Background: Macrodystrophia lipomatosa (MDL) is characterized by progressive overgrowth affecting soft tissues and bony structures and is part of lipomatous overgrowth syndromes. MDL has been associated with lipomatosis of the nerve (LN), an adipose lesion of nerve that has a pathognomonic magnetic resonance imaging (MRI) appearance as well as a mutation in the PIK3CA gene. The authors present a case of occult LN in the setting of MDL.

Plexal intraneural perineurioma: an analysis of the clinicoradiologic presentation of this rare variant.

Purpose: Intraneural (IN) perineurioma is a rare benign peripheral nerve sheath tumor, typically presenting as a painless, progressive mononeuropathy in adolescents. A rare plexal variant has been described, although there are little data describing its clinicoradiologic features. Herein, we present the largest case series of plexal IN perineuriomas reported in the literature.

Hybrid tumors with perineurioma components: a systematic review of the literature and illustrative case.

Purpose: Hybrid peripheral nerve sheath tumors (HPNST) are a newly recognized class of peripheral nerve sheath tumor, composed of at least two areas characteristic of perineurioma, schwannoma, or neurofibroma. The literature consists only of case reports and small series; therefore, we present an illustrative case and an analysis of all reported cases of HPNST with a perineurioma component in the literature.

Methods: A systematic search of the literature was performed to identify all reported cases of hybrid perineurioma-schwannoma or perineurioma-neurofibroma in the world's literature.