Nerve Root Sheath Research Articles

Thecaloscopy Reduces the Risk of Recurrent Perineural (Tarlov) Cysts after Microsurgical Resection.

Sacral Tarlov cysts (TCs), often asymptomatic, can cause significant pain and severe neurological dysfunction. Conventional treatments are generally associated with high recurrence and complication rates. Specifically, the substantial recurrence rates, which can reach as high as 50%, significantly impact long-term outcomes. Recent evidence increasingly supports the hypothesis that the formation of Tarlov cysts (TCs) may be associated with inflammatory processes within the nerve root sheath, further exacerbated by elevated cerebrospinal fluid (CSF) pressure. This retrospective study explores thecaloscopy, combined with surgical techniques, as a more effective alternative. We observed a total of 78 patients, 48 of whom underwent endoscopic fenestration of the arachnoid sheath in addition to microsurgical resection of the TC. We found that the fenestration of the arachnoid sheath at the level of lumbosacral spinal nerve root entry led to a significantly decreased risk of developing recurrent TCs (5/48 vs. 9/30). Only one of the patients suffered from a persistent new bladder dysfunction after microsurgical resection. This presented technique provides a promising treatment path for the future management of TCs, offering a safe and more effective treatment option compared to previous methods. Additionally, the advantages of the thecaloscopy provide pathophysiological implications regarding the development of perineural cysts.

Large- and Small-Fiber Neuropathy in Patients with Tarlov Cysts.

PurposeTarlov cysts (TCs) are dilated nerve root sheaths originating from increased cerebrospinal pressure. Patients with TCs often complain of neuropathic pain and paresthesia. The aim of this study was to retrospectively review intraepidermal nerve fiber density (IENFD) and electrodiagnostic (EDX) data from TC patients.Patients and MethodsLower leg skin biopsy results and EDX data from the L2–S4 myotomes of patients with lumbar or sacral TCs ≥8 mm were retrieved from a database of a physical medicine clinic. Patients with compressive pathology, diabetes mellitus and chemotherapy were excluded.ResultsIENFD data from 17 patients and EDX data from 24 patients with TCs ≥8 mm were available. The mean age was 47 ± 10y, and 83% were women. In 82% of patients, the IENFD was below the 5th percentile by age and sex. EDX showed increased Hoffmann reflex latencies in 25%, increased anal reflex latencies in 95%, and a patchy distribution of neurogenic motor unit potentials in 100%. More than 50% of needle EMG abnormalities appeared in myotomes unrelated to the location of the TCs.ConclusionSmall- and/or large-fiber neuropathy was documented in a significant proportion of patients with TCs. The novel findings may add to the understanding of the mechanisms involved in symptomatic TCs. We propose that pathologically elevated cerebrospinal fluid pressure not only dilates some of the nerve root sheaths to form TCs but also potentially damages axons in nondilated nerve root sheaths and neurons in the dorsal root ganglia.

Malignant Peripheral Nerve Sheath Tumour in a Seba's Short-Tailed Bat (Carollia perspicillata)

There are few reports of tumours in bats, despite the fact that members of the Chiroptera order include 22.4% of all currently known mammal species. We now describe a case of malignant peripheral nerve sheath tumour (MPNST) in an adult female Seba's short-tailed bat (Carollia perspicillata) from a private zoo in Switzerland. The macroscopical and histological findings indicated that the MPNST originated from a dorsal spinal nerve root sheath in the lumbar region and metastasized to the spleen. Immunohistochemical labelling for glial fibrillary acid protein, S100 protein, neuron specific enolase and synaptophysin was negative. The cytoplasm of a few neoplastic cells labelled for smooth muscle actin and desmin. To our knowledge, this is the first report of a PNST in a member of the Chiroptera order.

Spinal schwannoma causes acute subarachnoid haemorrhage: A case report and literature review

BackgroundSpinal schwannomas that arise from spinal nerve root sheaths are the most common intradural extramedullary spinal tumours and are often accompanied by nerve roots or spinal cord irritation symptoms. The phenomenon of spinal schwannoma causing subarachnoid haemorrhage (SAH) is rare, with ependymoma of the conus medullaris accounting for most cases. Case reportA 45-year-old man was admitted to our hospital due to progressive lower limb weakness and sudden back pain after hard physical work. The patient had not been able to walk for 2hours upon admission. An emergency magnetic resonance imaging (MRI) scan showed that the spinal cord at the C6-T4 level was severely compressed by a subdural mass. During the emergency operation, exploration of the dura and arachnoid mater revealed a fresh blood clot covering a tumour located on the ventral side of the spinal cord. The size of the tumour was approximately 3×2×1cm without adhesion to the surrounding tissue, but the drainage vein was ruptured. Postoperative pathology showed that the tumour was a schwannoma with areas of fresh haemorrhage and focal necrosis. ConclusionsSpinal schwannomas presenting with SAH are rare events. In our opinion, spinal pathology with rapid progression of neurological symptoms requires early diagnosis and emergency management. Complete excision of haemorrhagic tumours is the goal of treatment to prevent recurrence, which can effectively avoid irreversible damage to the spinal cord resulting from spinal cord compression.

Probable Cerebrospinal Fluid Infiltration into the Sacral Nerve Root Sheath and Exudation after Stagnant Retention in It, detected via Magnetic Resonance Imaging and Myelography : A Case Report

Probable Cerebrospinal Fluid Infiltration into the Sacral Nerve Root Sheath and Exudation after Stagnant Retention in It, detected via Magnetic Resonance Imaging and Myelography : A Case Report

Glue That Pain: A Case Report and Review of Literature

Tarlov cysts are cystic lesions of the nerve root sheath in the lower spine. With a reported incidence ranging from 1 to 5%, these lesions are fairly rare, benign and often asymptomatic. When they cause neural compression they may become symptomatic with sensory, motor, bowel/bladder and sexual dysfunction. The treatment of symptomatic Tarlov cysts is a controversial issue, ranging from conservative management and local steroid injections to a bewildering assortment of surgical options including CSF diversion procedures and advance microsurgical approaches with various ways of cyst manipulation. All these surgical modalities carry a high risk of serious complications, recurrence with need of a redo operation and a very variable rate of symptomatic relief ranging from 38 – 100 % in different series. Developing from the CT guided needle aspiration of the cyst which suffered disappointment in the form of re accumulation and heralded by earlier reports of aseptic meningitis, CT guided aspiration and subsequent filling of the cyst with fibrin glue has now emerged as a safe, highly effective and first line of treatment for symptomatic Tarlov cyst.

Symptomatic intraspinal lumbosacral pseudomeningocele, a late consequence of root avulsion injury secondary to a gunshot wound

BackgroundTraumatic pseudomeningocele are usually a late consequence of cervical root avulsion injury and its occurrence in lumbosacral region is rare. This pathology is mostly due to violent blunt traumatic events and usually develops outside of the spinal canal. Occasionally, a pseudomeningocele may grow inside of the spinal canal causing delayed neurological deficit due to compromise of the adjacent neural structures. Case descriptionEvaluation of a delayed left lower extremity weakness in a young man with a history of a gunshot wound injury revealed an extradural pseudomeningocele arising from an S1 root avulsion injury with compressive effect on the adjacent L5 root OutcomeExcision of the cyst wall and reinstitution of the nerve root sheath resulted in an uneventful recovery ConclusionTo the best of our knowledge, the presented case with traumatic pseudomeningocele is the first example secondary to high velocity bullet injury. Furthermore, management of traumatic intraspinal pseudomeningocele subsequent to root avulsion injury has not been paid sufficient attention. In this paper, the surgical strategy will be discussed in detail.

Hydrocephalus associated with multiple Tarlov cysts

Tarlov cysts (TCs) consist of dilated nerve root sheaths filled with cerebrospinal fluid (CSF) and are most frequently found in the sacrum. It is estimated that 25% of detected TCs cause chronic pain and intestinal and urogenital symptoms due to compression of the sacral nerve root fibers inside the TC. Unfortunately, symptomatic TCs are frequently overlooked.It is assumed that TCs result from pathologically increased hydrostatic pressure (HP) in the dural sac that forces CSF into the nerve root sheaths. We hypothesize that in patients with TCs, increased spinal hydrostatic pressure is always associated with increased intracranial pressure. This hypothesis of increased cerebrospinal pressure might explain why patients with sacral TCs frequently report distant symptoms, such as headaches and pain in the neck and arms.In this paper, we describe a case report that provides evidence for this hypothesis.A 30-year-old man presented for the first time in our clinic complaining of lower back, leg, thoracic, neck, and arm pain; headaches; and bladder, bowel, and sphincter symptoms.He was born prematurely and suffered cerebral intraventricular bleeding followed by progressive hydrocephalus. Progression was stabilized with acetazolamide and lumbar punctures. At 19 years of age, his head circumference had further increased and he reported back pain and headaches. Fundoscopy showed no papilledema, and lumbar puncture for CSF evacuation improved the headaches and back pain. The former medical team chose not to insert a ventriculo-external shunt.Brain magnetic resonance imaging (MRI) showed significant dilation of all the ventricles. No CSF flow obstruction between the ventricles was observed.Surprisingly, MRI of the lumbar and sacral spine showed multiple large TCs.This case report indicates that hydrocephalus with a patent aqueduct may be associated with TCs because the increased intracranial pressure is transferred to the spinal canal. While increased intracranial pressure causes dilation of the ventricles, the associated increased spinal pressure may cause dilation of multiple spinal nerve root sheaths to form TCs. Furthermore, while the increased volume of the ventricles gradually compresses the neurons and axons of the brain against the bony skull, simultaneously, the increased pressure inside the nerve sheaths may also gradually compress the neurons and axons located inside the dorsal root ganglia and spinal nerves, resulting in neuropathic pain, sensory abnormalities, and neurogenic bladder and bowel symptoms.Hydrocephalus patients reporting neuropathic pain should be screened for the presence of TCs.

A systematic comparative outcome analysis of surgical versus percutaneous techniques in the management of symptomatic sacral perineural (Tarlov) cysts: a meta-analysis.

Symptomatic perineural or Tarlov cysts (TCs) are a rare cause of chronic low-back pain. Given the rarity of the disease, there is no literature consensus regarding the optimal management of these cysts. The authors conducted a systematic comparative outcome analysis of symptomatic TCs treated with surgery (group A, 32 studies, n = 333) or percutaneous interventions (group B, 6 studies, n = 417) analyzing the demographic characteristics, baseline characteristics of the cysts, clinical presentations, types of interventions, complication rates, and the recurrence rate in both treatment groups. The literature search was performed using the PubMed, MEDLINE, Cochrane, and Ovid databases up to 2018. The MeSH search terms used were "Tarlov cyst," "sacral perineural cyst," "sacral nerve root cyst," "meningeal cyst of the sacral spine," "extra meningeal cyst with spinal nerve root fibers," "spinal extradural arachnoid pouch," and "cyst of the sacral nerve root sheath." The authors used statistical tests for two proportions using the "N-1" chi-square test with the free version of MedCalc for Windows for comparison among the groups. Overall symptomatic improvement was reported in 83.5% of patients in both groups; however, exacerbation of preprocedural symptoms was significantly higher in group B than group A (10.1% vs 3.3%, p = 0.0003). The overall complication rates in the surgical and nonsurgical groups were 21% and 12.47%, respectively. Transient sciatica was the most common complication in both groups (17% vs 8%, respectively; p = 0.017). The incidence of cyst recurrence was much lower in group A than group B (8% vs 20%, p = 0.0018). The mean follow-up duration for the surgical group was 38 ± 29 months (25 studies, n = 279), while that for the nonsurgical group was 15 ± 12 months (4 studies, n = 290) (p < 0.0001). The authors noted that although the surgical interventions were associated with higher postprocedural complication rates, long-term efficacy and success in terms of cyst resolution were superior following surgery compared to percutaneous procedures in the management of symptomatic TCs. There was no difference in symptom recurrence with either of the techniques.

NEUROFIBROMATOSIS TYPE 1

Background Neurofibromatosis type 1 (NF1), a complex multisystemic disorder caused by a genetic mutation on chromosome 17, causes uncontrolled tumor growths (called neurofibromas) in the nervous system. There are numerous conditions and complications associated with this disorder, which can affect the skin, eye, muscle, bone, and nervous system. We are presenting 2 cases of NF1 evaluated by using advanced imaging modalities. Clinical and Radiographic Findings Case #1: 20-year-old female, who had been referred to our department at age 15 years for preradiation therapy dental screening. Computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography–CT (PET-CT) studies were performed, and they demonstrated aggressive invasive nasopharyngeal carcinoma, metastatic cervical and retropharyngeal lymphadenopathy, and numerous plexiform neurofibromas along the expected course of cranial nerves (CNs) VII, IX, X, XI, and XII, and along the peripheral path of CN V. Throughout the neck, the NFs virtually involved all of the cervical nerve root sheaths and extended to the mediastinum. Case #2: 53-year-old female, who presented to the University of Florida Emergency Department complaining of right facial swelling, pain, and hearing impairment. CT and MRI of the head were performed, and they demonstrated suspicious right preauricular thrombosis of an enlarged facial vein versus evolution of hematoma, multiple skin/subcutaneous NFs, plexiform NF in the distribution of the trigeminal nerve on the right side with related atrophy of the muscles of mastication, enophtalmos, and dysplasia of the skull base, mandible, and facial bones. Definitive Interpretation Neurofibromatosis type 1. Discussion/Conclusions Patients with NF1 are at risk of eventual development of malignancy. For this reason, patients with NF1 need to be evaluated periodically by multiple specialists, using advanced imaging modalities, and it is important for dental professionals to recognize this disorder and be proactive in its interdisciplinary management.

The link between idiopathic intracranial hypertension, fibromyalgia, and chronic fatigue syndrome: exploration of a shared pathophysiology.

PurposeIdiopathic intracranial hypertension (IICH) is a condition characterized by raised intracranial pressure (ICP), and its diagnosis is established when the opening pressure measured during a lumbar puncture is elevated >20 cm H2O in nonobese patients or >25 cm H2O in obese patients. Papilledema is caused by forced filling of the optic nerve sheath with cerebrospinal fluid (CSF). Other common but underappreciated symptoms of IICH are neck pain, back pain, and radicular pain in the arms and legs resulting from associated increased spinal pressure and forced filling of the spinal nerves with CSF. Widespread pain and also several other characteristics of IICH share notable similarities with characteristics of fibromyalgia (FM) and chronic fatigue syndrome (CFS), two overlapping chronic pain conditions. The aim of this review was to compare literature data regarding the characteristics of IICH, FM, and CFS and to link the shared data to an apparent underlying physiopathology, that is, increased ICP.MethodsData in the literature regarding these three conditions were compared and linked to the hypothesis of the shared underlying physiopathology of increased cerebrospinal pressure.ResultsThe shared characteristics of IICH, FM, and CFS that can be caused by increased ICP include headaches, fatigue, cognitive impairment, loss of gray matter, involvement of cranial nerves, and overload of the lymphatic olfactory pathway. Increased pressure in the spinal canal and in peripheral nerve root sheaths causes widespread pain, weakness in the arms and legs, walking difficulties (ataxia), and bladder, bowel, and sphincter symptoms. Additionally, IICH, FM, and CFS are frequently associated with sympathetic overactivity symptoms and obesity. These conditions share a strong female predominance and are frequently associated with Ehlers-Danlos syndrome.ConclusionIICH, FM, and CFS share a large variety of symptoms that might all be explained by the same pathophysiology of increased cerebrospinal pressure.

Spinal fluid evacuation may provide temporary relief for patients with unexplained widespread pain and fibromyalgia

Fibromyalgia (FM) exhibits characteristics of a neurological disorder, and similarities have been identified between FM and idiopathic intracranial hypertension (IICH). When intracranial pressure rises, the drainage of excess cerebrospinal fluid (CSF) through the subarachnoid space of the cranial and spinal nerves increases. Higher CSF pressure irritates nerve fibers inside nerve root sheaths and may consequently cause radicular pain, as was reported in patients with IICH. Moreover, the cut-off of 20–25 cm H20 used to define IICH may be too high, as has been suggested in patients with chronic fatigue syndrome. We hypothesize that the neurological symptoms of FM are caused by the dysregulation of cerebrospinal pressure (CSP) and that spinal fluid drainage can relieve this pain.Exploring the processes underlying increased CSP may provide an alternative explanation for the generation of unexplained widespread pain (WSP) and FM as opposed to central sensitization.Additionally, when performing a lumbar puncture for diagnostic reasons, it is useful to measure opening pressure in patients with chronic WSP.

Can patients with symptomatic Tarlov cysts be differentiated from patients with specific low back pain based on comprehensive history taking?

Tarlov cysts (TCs) are expanded nerve root sheaths that occur near the dorsal root ganglion and result from increased intraspinal hydrostatic pressure. TCs most frequently affect the lumbosacral plexus and therefore may cause specific symptoms such as perineal pain and neurogenic bladder, bowel, and sphincter problems. It has been estimated that 1% of the population has symptomatic Tarlov cysts (STCs). However, STCs appear to be underdiagnosed, with the pain reported by patients commonly attributed to degenerative alterations seen on MRI. The aim of the present study is to investigate the utility of a comprehensive questionnaire for use by physicians in establishing the diagnosis of STCs. We compared questionnaire responses regarding patient history between 33 patients diagnosed with symptomatic TCs and 42 patients with chronic low back pain and sciatica due to disc problems or degenerative or inflammatory disorders. The diagnosis of STCs was confirmed using nerve conduction studies (NCS) and electromyography (EMG) of the sacral myotomes by an expert neurophysiologist. The questionnaire responses revealed specific differences in perineal symptoms (perineal pain, dyspareunia, coccygodynia), bowel symptoms (constipation, diarrhea), bladder symptoms (hesitation, retention, frequency), and anal sphincter problems (anal pain, mild fecal incontinence). Additionally, sitting, walking, and straining aggravated pain more frequently in STC patients, and STC patients were more often forced to stop working and/or reduce their social activities. Including the above-listed items in the patient history might facilitate differentiation of low back pain and sciatica due to STCs from that due to disc problems or degenerative or inflammatory disorders.

Adnexal masses or perineural (tarlov) cysts? Differentiation by imaging techniques: A case report

Perineural cysts formed within the nerve-root sheath at the dorsal root ganglion. They are most commonly located in the arachnoid covering the junction of the dorsal ganglion and nerve root. They are usually asymptomatic, incidental findings, usually located in the lumbar and sacral region of the spinal canal. It is important to consolidate the imaging findings of this rare disease so clinicians can become more clinically relevant in the evaluation of these cysts. Herein we report a case of perineural cyst misdiagnosed with hydrosalpinx by pelvic ultrasonography and finally diagnosed with magnetic resonance image. Perineural cyst should be considered, in the presence of bilateral adnexal masses separated from the ovaries in pelvic sonography.

Incomplete cauda equina syndrome secondary to haemorrhage within a Tarlov cyst

Sacral perineural (Tarlov) cysts are benign, cerebrospinal fluid containing lesions of the spinal nerve root sheath. They are usually asymptomatic; however, a small proportion have the potential to cause compression...

A Case Report: Symptomatic Sacral Tarlov Cyst in a Male of 24 Years

Perineural (Tarlov) cyst, a rare but benign condition, is meningeal dilatations of the posterior spinal nerve root sheath that most often affects sacral roots and can cause a progressive painful radiculopathy. Tarlov cysts are most commonly diagnosed by lumbosacral magnetic resonance imaging (MRI) and can often be demonstrated by computerized tomography (CT) to communicate with the spinal subarachnoid space. The cyst can enlarge via a net inflow of cerebrospinal fluid, eventually causing symptoms by distorting, compressing, or stretching adjacent nerve roots. It is generally agreed that asymptomatic Tarlov cysts do not require treatment. When symptomatic, the potential surgery-related benefit and the specific surgical intervention remain controversial. A 24 years old male presented with a history of trauma and pain in his low back with dull headache for six months. Physical and radiographic examination was consistent with tarlov cyst. Microsurgical excision with plication of the cyst wall was performed. Histo-pathological examination confirmed the diagnosis of Tarlov cyst. Excellent clinical and functional results were obtained with no recurrence after 6 months of follow-up. Tarlov cyst in a male of age 24 is a rare entity and decision making for management poses difficulties. Our experience with microsurgical excision with plication of the cyst wall was quite satisfactory with excellent clinical result, and we recommend this as one of the satisfactory modalities of treatment of Tarlov cyst in adult.Delta Med Col J. Jul 2017 5(2): 99-103

Cervical extraforaminal ligaments: an anatomical study.

The purpose of this study was to elucidate the anatomy and clinical importance of extraforaminal ligaments in the cervical region. This study was performed on eight embalmed cadavers. The existence and types of extraforaminal ligaments were identified. The morphology, quantity, origin, insertion, and orientation of the extraforaminal ligaments in the cervical region were observed. Extraforaminal ligaments could be divided into two types: transforaminal ligaments and radiating ligaments. It was observed that during their course, transforaminal ligaments cross the intervertebral foramen ventrally. They usually originate from the anteroinferior margin of the anterior tubercle of the cranial transverse process and insert into the superior margin of the anterior tubercle of the caudal transverse process. The dorsal aspect of the transforaminal ligaments adhere loosely to the spinal nerve sheath. The length, width and thickness of these ligaments increased from the cranial to the caudal direction. A single intervertebral foramen contained at least one transforaminal ligament. A total of 98 ligaments in 96 intervertebral foramina were found. The spinal nerves were extraforaminally attached to neighboring anterior and posterior tubercle of the cervical transverse process by the radiating ligaments. The radiating ligaments consisted of the ventral superior, ventral, ventral inferior, dorsal superior and dorsal inferior radiating ligaments. Radiating ligaments originated from the adjacent transverse processes and inserted into the nerve root sheath. The spinal nerve was held like the hub of a wheel by a series of radiating ligaments. The dorsal ligaments were the thickest. From C2-3 to C6-7 at the cervical spine, radiating ligaments were observed. They developed particularly at the level of the C5-C6 intervertebral foramen. This anatomic study may provide a better understanding of the relationship of the extraforaminal ligaments to the cervical nerve root.

Totally cystic intradural schwannoma in thoracic region

Spinal schwannomas are benign intradural extramedullary tumors arising from spinal nerve root sheath. They are usually solid or heterogeneously solid. Totally cystic schwannomas are rare entities. Herein, we report a 60-year-old male presenting with backache radiating along the chest wall and weakness of both lower limbs. He had spastic paraparesis. Magnetic resonance imaging revealed a cystic mass in the thoracic region. At operation, the cystic mass was seen to be attached to D4 dorsal rootlets. It was excised in toto and histopathology confirmed it to be a schwannoma. The relevant literature is reviewed.

Tarlov cyst – an uncommon cause of back pain

Tarlov cysts, also known as perineural or sacral nerve root cysts, are cerebrospinal fluid-filled dilatations of the nerve root sheath most commonly found at the sacral spine, near the dorsal root ganglion. The cysts are relatively rare and usually asymptomatic, but some can exert pressure on the nerve root, causing perineal pain/discomfort or lower back pain or sphincter/sexual dysfunction. Tarlov (perineural) cysts of the nerve roots were first described in 1938.

The Tarlov cyst: A cause of sciatica

Our goal is to study through this observation and review of the literature the role of Tarlov cyst in the occurrence of lombosciatalgias and therapeutic possibilities. Mrs. H.M 48 years old, with no notable medical history, is hospitalized in Physical Medicine and Functional Rehabilitation department CHU Sahloul for a right S1 radiculopathy associated with a subjective feeling of lower extremity weakness evolving for one year. Clinical examination found a spinal syndrome, absence of discoradicular conflict signs and a plantar flexion deficit of the right ankle. A lumbar MRI reported a cystic lesion in right neural foramen of S2 of 15 mm size. The patient received two epidural by the sacro coccygeal hiatus separated by an interval of 6 days. The evolution was characterized by improved lombo-radicular pain. Perineural (Tarlov) cysts are meningeal dilatations of the posterior spinal nerve root sheath that found most commonly in the sacral roots, but can see much more rarely, lumbar, dorsal and cervical roots. These cysts are relatively rare and most of them are asymptomatic. Some cysts can have nerve compression, causing sacral or lumbar pain syndromes, sciatica or rarely as cauda equina syndrome. The Tarlov cysts are typically benign lesion. These cysts are rarely sources of complications due to distorting, compressing, or stretching of adjacent sacral nerve roots. These are symptomatic in 12% of cases and responsible of 0.2% of the lumbosacral radicular pain. An MRI gives a much better soft tissue contrast and is currently the gold-standard investigation in identifying perineural cysts and to study their relationship with surrounding structures. Treatment may be medical or surgical that is aimed at symptomatic Tarlov cysts.