Physician distress when treatments fail. Survey on physician distress when treating persons with drug-resistant epilepsy and knowledge of neuropalliative care.

OBJECTIVE: Drug-resistant epilepsy can be difficult to cure and may pose emotional challenges for epilepsy providers. Neuropalliative care (NPC) can augment quality of life (QOL) in persons with neurological diseases and may add meaningful elements to the treatment repertoire of epilepsy specialists even if seizures continue. However, NPC has not been widely implemented in epilepsy. Our study aimed to determine whether physicians of persons with drug-resistant epilepsy (PWDRE) experience distress when faced with treatment failure (Engel class ≥ 2), either failure of medications-only (PWDREmo) or of both medications and surgery (procedures with curative intent (PWDREms)). Furthermore, we evaluated physician knowledge about and referrals to NPC following treatment failures to help improve patient QOL despite ongoing seizures. METHODS: An anonymous online survey was distributed to US epilepsy physicians through the American Epilepsy Society website and personal email to assess levels of distress experienced when caring for PWDREmo and PWDREms (7-point Likert scale ["1" = "no distress", "7" = "most distress ever felt"]), and knowledge and use of NPC. RESULTS: Eighty-two physicians completed the survey. Most experienced distress when epilepsy treatments failed: 59% felt moderate distress (≥4) with PWDREmo (median "4", mean 3.74, range 1-7), 90% suffered moderate to severe distress (5, 5.17, 1-7) with PWDREms. Distress over PWDREms was significantly greater than distress over PWDREmo (p < 0.0001). Forty-three percent reported confidence in their knowledge about NPC. Only 15% were likely to refer PWDREmo to NPC, while 44% would consider it for PWDREms. CONCLUSION: Among survey responders, physician distress was high when confronted with treatment failures, especially the failure of epilepsy surgery. Fewer than half of responders were likely to refer patients to NPC. Further research is necessary to determine extent, reasons, and effects of physician distress and whether improved understanding of and patient access to NPC would help alleviate physician distress when faced with treatment failures in PWDRE.

Using a Robotic-Assisted Approach for Stereotactic Laser Ablation Corpus Callosotomy: A Technical Report.

BACKGROUND: Corpus callosotomy for medically intractable epilepsy is an effective ablative procedure traditionally achieved using either standard open craniotomy or with less-invasive approaches. Advances in robotic-assisted stereotactic guidance for neurosurgery can be applied for LITT for corpus callosotomy. CLINICAL PRESENTATIONS: Two patients were included in this study. One was a 25-year-old female patient with extensive bi-hemispheric malformations of cortical development and medically refractory epilepsy, and the other was an 18-year-old male with medically refractory epilepsy and atonic seizures, who underwent a complete corpus callosotomy using robotic-assisted stereotactic guidance for LITT. RESULTS: Both patients underwent successful intended corpus callosotomy with volumetric analysis demonstrating a length disconnection of 74% and a volume disconnection of 55% for patient 1 and a length disconnection of 83% and a volume disconnection of 33% for patient 2. Postoperatively, both patients had clinical reductions in seizure. CONCLUSION: Our experience demonstrates that robotic guidance systems can safely and effectively be adapted for minimally invasive LITT corpus callosotomy.

Epilepsy in Parry-Romberg syndrome and linear scleroderma en coup de sabre: Case series and systematic review including 140 patients.

Parry-Romberg syndrome (PRS) and linear sclerosis en coup de sabre (LScs) are rare, related, autoimmune conditions of focal atrophy and sclerosis of head and face which are associated with the development of focal epilepsy. The scarcity of PRS and LScs cases has made an evidence-based approach to optimal treatment of seizures difficult. Here we present a large systematic review of the literature evaluating 137 cases of PRS or LScs, as well as three new cases with epilepsy that span the spectrum of severity, treatments, and outcomes in these syndromes. Analysis showed that intracranial abnormalities and epileptic foci localized ipsilateral to the external (skin, eye, mouth) manifestations by imaging or EEG in 92% and 80% of cases, respectively. Epilepsy developed before external abnormalities in 19% of cases and after external disease onset in 66% of cases, with decreasing risk the further from the start of external symptoms. We found that over half of individuals affected may achieve seizure freedom with anti-seizure medications (ASMs) alone or in combination with immunomodulatory therapy (IMT), while a smaller number of individuals benefitted from epilepsy surgery. Although analysis of case reports has the risk of bias or omission, this is currently the best source of clinical information on epilepsy in PRS/LScs-spectrum disease. The paucity of higher quality information requires improved case identification and tracking. Toward this effort, all data have been deposited in a Synapse.org database for case collection with the potential for international collaboration.

Would people living with epilepsy benefit from palliative care?

Palliative care (PC) is an approach to the care of persons living with serious illness and their families that focuses on improving quality of life and reducing suffering by addressing complex medical symptoms, psychosocial needs, spiritual well-being, and advance care planning. While PC has traditionally been associated with hospice care for persons with cancer, there is now recognition that PC is relevant to many noncancer diagnoses, including neurologic illness, and at multiple points along the illness journey, not just end of life. Despite the recent growth of the field of neuropalliative care there has been scant attention paid to the relevance of PC principles in epilepsy or the potential for PC approaches to improve outcomes for persons living with epilepsy and their families. We believe this has been a significant oversight and that PC may provide a useful framework for addressing the many sources of suffering facing persons living with epilepsy, for engaging patients and families in challenging conversations, and to focus efforts to improve models of care for this population. In this manuscript we review areas of significant unmet needs where a PC approach may improve patient and family-centered outcomes, including complex symptom management, goals of care, advance care planning, psychosocial support for patient and family and spiritual well-being. When relevant we highlight areas where epilepsy patients may have unique PC needs compared to other patient populations and conclude with suggestions for future research, clinical, and educational efforts.

Responsive neurostimulation for refractory epilepsy in the pediatric population: A single-center experience.

Drug-resistant focal epilepsy (DRFE) in children can impair cognition and behavior, and lead to premature death. Increased pediatric epilepsy surgery numbers reflect the improvements in seizure control and long-term developmental outcomes. Yet, many children with DRFE are not candidates for surgical resection due to overlap of the seizure network with eloquent cortex or multiple seizure-onset zones, making surgery dangerous or ineffective. In adults, responsive neurostimulation (RNS System) therapy is safe and effective treatment for DRFE with one or two seizure foci, especially when the seizure focus is in eloquent cortex. We present six pediatric patients with DRFE who underwent RNS implantation. Our outcomes demonstrate safety, decreased clinical seizure frequency, as well as improved functional status and quality of life. Changes in the clinical seizure semiology and frequency occurred in conjunction with adjustments to the stimulation parameters, supporting the efficacy of responsive neuromodulation in children.

Seizure outcome with responsive neurostimulation (RNS) comparing strip versus depth leads.

OBJECTIVE: This study aimed to compare seizure outcomes and complication rates in patients treated with only responsive neurostimulation (RNS) strip leads with those treated with only RNS depth leads. METHODS: A retrospective cohort study was performed using the institutional epilepsy surgery database. Included was any patient implanted with the RNS system between August 2015 and May 2018 with either two depth (2D) or two strip (2S) leads connected to the device and at least 6 months follow-up. Excluded were those with a combination of active depth and strip leads. Data extracted from the charts comprised demographic information, duration of epilepsy, presence of a magnetic resonance imaging (MRI) lesion, prior resective surgery, clinically disabling seizures at baseline and follow-up, prior invasive monitoring, location (mesial temporal or neocortical) and number of seizure foci, unilateral or bilateral RNS lead placement, and postoperative complications. RESULTS: Of 48 screened patients, 34 met study inclusion criteria. Of these, 15 were treated with 2D leads and 19 with 2S leads. Groups 2D and 2S were comparable with respect to age at onset, duration of epilepsy, baseline seizure frequency, and exposure time to RNS. After adjustment for patient age and duration of epilepsy, seizure frequency in 2S patients was noted to be decreased by 83% (p = 0.046), while it was reduced by 51% (p = 0.080) in 2D patients. The complication rate was not significantly different between the two groups. CONCLUSION: In our small retrospective population, patients with RNS strip leads experienced a significantly greater seizure reduction than patients with RNS depth leads, without a difference in complication rate.

Real-world experience with direct brain-responsive neurostimulation for focal onset seizures.

OBJECTIVE: The RNS System is a direct brain-responsive neurostimulation system that is US Food and Drug Administration-approved for adults with medically intractable focal onset seizures based on safety and effectiveness data from controlled clinical trials. The purpose of this study was to retrospectively evaluate the real-world safety and effectiveness of the RNS System. METHODS: Eight comprehensive epilepsy centers conducted a chart review of patients treated with the RNS System for at least 1 year, in accordance with the indication for use. Data included device-related serious adverse events and the median percent change in disabling seizure frequency from baseline at years 1, 2, and 3 of treatment and at the most recent follow-up. RESULTS: One hundred fifty patients met the criteria for analysis. The median reduction in seizures was 67% (interquartile range [IQR] = 33%-93%, n = 149) at 1 year, 75% (IQR = 50%-94%, n = 93) at 2 years, 82% (IQR = 50%-96%, n = 38) at ≥3 years, and 74% (IQR = 50%-96%, n = 150) at last follow-up (mean = 2.3 years). Thirty-five percent of patients had a ≥90% seizure frequency reduction, and 18% of patients reported being clinically seizure-free at last follow-up. Seizure frequency reductions were similar regardless of patient age, age at epilepsy onset, duration of epilepsy, seizure onset in mesial temporal or neocortical foci, magnetic resonance imaging findings, prior intracranial monitoring, prior epilepsy surgery, or prior vagus nerve stimulation treatment. The infection rate per procedure was 2.9% (6/150 patients); five of the six patients had an implant site infection, and one had osteomyelitis. Lead revisions were required in 2.7% (4/150), and 2.0% (3/150) of patients had a subdural hemorrhage, none of which had long-lasting neurological consequences. SIGNIFICANCE: In this real-world experience, safety was similar and clinical seizure outcomes exceeded those of the prospective clinical trials, corroborating effectiveness of this therapy and suggesting that clinical experience has informed more effective programming.

Mesial temporal resection following long-term ambulatory intracranial EEG monitoring with a direct brain-responsive neurostimulation system.

OBJECTIVE: To describe seizure outcomes in patients with medically refractory epilepsy who had evidence of bilateral mesial temporal lobe (MTL) seizure onsets and underwent MTL resection based on chronic ambulatory intracranial EEG (ICEEG) data from a direct brain-responsive neurostimulator (RNS) system. METHODS: We retrospectively identified all patients at 17 epilepsy centers with MTL epilepsy who were treated with the RNS System using bilateral MTL leads, and in whom an MTL resection was subsequently performed. Presumed lateralization based on routine presurgical approaches was compared to lateralization determined by RNS System chronic ambulatory ICEEG recordings. The primary outcome was frequency of disabling seizures at last 3-month follow-up after MTL resection compared to seizure frequency 3 months before MTL resection. RESULTS: We identified 157 patients treated with the RNS System with bilateral MTL leads due to presumed bitemporal epilepsy. Twenty-five patients (16%) subsequently had an MTL resection informed by chronic ambulatory ICEEG (mean = 42 months ICEEG); follow-up was available for 24 patients. After MTL resection, the median reduction in disabling seizures at last follow-up was 100% (mean: 94%; range: 50%-100%). Nine patients (38%) had exclusively unilateral electrographic seizures recorded by chronic ambulatory ICEEG and all were seizure-free at last follow-up after MTL resection; eight of nine continued RNS System treatment. Fifteen patients (62%) had bilateral MTL electrographic seizures, had an MTL resection on the more active side, continued RNS System treatment, and achieved a median clinical seizure reduction of 100% (mean: 90%; range: 50%-100%) at last follow-up, with eight of fifteen seizure-free. For those with more than 1 year of follow-up (N = 21), 15 patients (71%) were seizure-free during the most recent year, including all eight patients with unilateral onsets and 7 of 13 patients (54%) with bilateral onsets. SIGNIFICANCE: Chronic ambulatory ICEEG data provide information about lateralization of MTL seizures and can identify additional patients who may benefit from MTL resection.

The impact of cannabis use on intracarotid amobarbital testing.

Chronic cannabis use impacts memory functioning, even while users are not acutely intoxicated. The impact of cannabis use on Wada or intracarotid amobarbital testing (IAT) has not previously been described. We reviewed cannabis consumption in epilepsy patients undergoing IAT during pre-surgical work-up. Of 58 patients reviewed, 16 patients (28%) indicated regular use. During IAT, five regular cannabis users with suspected temporal lobe epilepsy exhibited poor memory while testing their presumptively healthy temporal lobe (i.e., the side opposite that targeted for epilepsy surgery), indicating the potential for an amnestic syndrome post-operatively. It was suspected that the pattern of IAT results for these patients was attributable to the deleterious impact of cannabis use on cognition. Thus, three of the five underwent repeat IAT after a period of enforced abstinence. On repeat IAT, each of the three patients exhibited improved memory performance while testing their healthy temporal lobe, suggesting that the healthy temporal lobe of each mediated sufficient memory ability to allow for epilepsy surgery. These findings raised concerns that frequent cannabis use may alter IAT results, leading to incorrect assessments regarding potential post-operative cognitive deficits, and led to a mandate at our institution that patients must stop cannabis use before IAT.

Outcomes after hemispherectomy in adult patients with intractable epilepsy: institutional experience and systematic review of the literature.

OBJECTIVE Hemispherectomy is a surgical technique that is established as a standard treatment in appropriately selected patients with drug-resistant epilepsy. It has proven to be successful in pediatric patients with unilateral hemispheric lesions but is underutilized in adults. This study retrospectively evaluated the clinical outcomes after hemispherectomy in adult patients with refractory epilepsy. METHODS This study examined 6 cases of hemispherectomy in adult patients at Barrow Neurological Institute. In addition, all case series of hemispherectomy in adult patients were identified through a literature review using MEDLINE and PubMed. Case series of patients older than 18 years were included; reports of patients without clear follow-up duration or method of validated seizure outcome quantification were excluded. Seizure outcome was based on the Engel classification. RESULTS A total of 90 cases of adult hemispherectomy were identified, including 6 newly added by Barrow Neurological Institute. Sixty-five patients underwent functional hemispherectomy; 25 patients had anatomical hemispherectomy. Length of follow-up ranged from 9 to 456 months. Seizure freedom was achieved in 80% of patients. The overall morbidity rate was low, with 9 patients (10%) having new or additional postoperative speech or language dysfunction, and 19 patients (21%) reporting some worsening of hemiparesis. No patients lost ambulatory or significant functional ability, and 2 patients had objective ambulatory improvement. Among the 41 patients who underwent additional formal neuropsychological testing postoperatively, overall stability or improvement was seen. CONCLUSIONS Hemispherectomy is a valuable surgical tool for properly selected adult patients with pre-existing hemiparesis and intractable epilepsy. In published cases, as well as in this series, the procedure has overall been well tolerated without significant morbidity, and the majority of patients have been rendered free of seizures.

Curative and palliative MRI-guided laser ablation for drug-resistant epilepsy.

Epilepsy is a common neurological disorder occurring in 3% of the US adult population. It is characterised by seizures resulting from aberrant hypersynchronous neural activity. Approximately one-third of newly diagnosed epilepsy cases fail to become seizure-free in response to antiseizure drugs. Optimal seizure control, in cases of drug-resistant epilepsy, often requires neurosurgical intervention targeting seizure foci, such as the temporal lobe. Advances in minimally invasive ablative surgical approaches have led to the development of MRI-guided laser interstitial thermal therapy (LITT). For refractory epilepsy, this surgical intervention offers many advantages over traditional approaches, including real-time lesion monitoring, reduced morbidity, and in some reports increased preservation of cognitive and language processes. We review the use of LITT for epileptic indications in the context of its application as a curative (seizure freedom) or palliative (seizure reduction) measure for both lesional and non-lesional forms of epilepsy. Furthermore, we address the use of LITT for a variety of extratemporal lobe epilepsies. Finally, we describe clinical outcomes, limitations and future applications of LITT for epilepsy.

Imaging of Laser Therapy in Epilepsy.

BACKGROUND AND PURPOSE: MR-guided laser interstitial thermal therapy (MRgLITT) is an increasingly popular neuroablative method for the surgical treatment of epilepsy patients. This article intends to demonstrate the utility and pitfalls of imaging in the context of patient care with MRgLITT. MATERIAL AND METHODS: A retrospective review of the medical records and imaging database with six illustrative cases selected to demonstrate the use of imaging throughout patient management with MRgLITT in diverse clinical situations and pathologies. A review of the knowledge in the literature was applied to the relevant points discussed. RESULTS: Imaging findings were described in the setting of laser therapy in nonlesional epilepsy, mesial temporal sclerosis, dual pathology, periventricular nodular heterotopia, and schizencephaly. Discussion of imaging principles, potential pitfalls, as well as its use in the patient work-up and follow-up, is shown. CONCLUSIONS: MRgLITT is an alternative minimally invasive therapy for refractory epilepsy, which is becoming widely sought for. Imaging plays a crucial role prior to, during, and after the procedure.

Optic Radiation Tractography and Visual Field Deficits in Laser Interstitial Thermal Therapy for Amygdalohippocampectomy in Patients with Mesial Temporal Lobe Epilepsy.

BACKGROUND/AIMS: Laser interstitial thermal therapy (LITT) has become an alternative to open-resective surgery for refractory mesial temporal lobe epilepsy (MTLE). Occurrence of visual field defects (VFDs) following open surgery for MTLE is reported at 52-100%. We examined the rate of VFDs following LITT for amygdalohippocampectomy (AHE) and correlated the occurrence of VFDs with damage to the optic radiations, assessed by diffusion tensor tractography (DTI). METHODS: We performed a retrospective analysis of 5 patients who underwent LITT-AHE for medically refractory MTLE. We examined the association between VFDs and optic radiation damage by correlating postprocedural visual field testing with qualitative assessment of optic radiation fiber tracts. RESULTS: Postoperative assessments showed that 4 patients had normal visual field testing, and 1 had a right superior quadrantanopsia (20%). We performed 3-dimensional reconstruction of the optic radiation, laser probe trajectory, and ablation volume. Damage to Meyer's loop was determined consistent with the VFD. CONCLUSIONS: Short-term follow-up in our series suggests that laser ablation AHE may be associated with a lower rate of VFD than has been reported for open AHE. Our results suggest that incorporating optic radiation mapping through DTI may preoperatively help to minimize the risk of VFD following laser ablation AHE.

Preoperative evaluation for epilepsy surgery: Process improvement.

BACKGROUND: Epilepsy surgery (ES) can improve seizure outcome. A prolonged duration of presurgical evaluation contributes to epilepsy-related morbidity and mortality. We introduced process changes to decrease evaluation time (ET) and increase ES numbers (excluding vagus nerve stimulation). METHODS: The University of Colorado Hospital patient database was searched for ESs between January 2009 and May 2016. Measures to reduce ET included (1) increasing patient care conference (PCC) frequency; (2) faster intracarotid amobarbital test (IAT) scheduling; (3) dedicated ES clinic; and (4) adding a nurse navigator. ET from noninvasive video-EEG monitoring (P1) to IAT, PCC, and ES, and ES volume were determined and compared for a baseline group (P1 January 2009-March 2013) and a group exposed to process changes (P1 after March 2013), the postchanges group, to assess the effect of these measures. RESULTS: ES number was 61 for the baseline group and 77 for the postchanges group, increasing the annual rate at 3 years after changes from 14.4 to 36.8 (p = 0.0008; 37% yearly increase postchanges). Interventions lowered average ET by 96 days (p ≤ 0.0001), P1 to IAT by 39 days (p = 0.0011), and P1 to PCC by 58 days (p = 0.0002). CONCLUSIONS: Simple process changes, including more frequent patient care conferences, faster scheduling, a dedicated ES clinic, and a nurse navigator significantly decreased evaluation times and increased ES numbers. Centers could utilize similar strategies to improve process and surgical volume and thereby increase patient seizure control and safety.

Seizure outcome and complications following hypothalamic hamartoma treatment in adults: endoscopic, open, and Gamma Knife procedures.

OBJECT: This study aimed at identifying outcomes with respect to seizures, morbidity, and mortality in adult patients undergoing resective or Gamma Knife surgery (GKS) to treat intractable epilepsy associated with hypothalamic hamartoma (HH). METHODS: Adult patients undergoing surgical treatment for HH-related epilepsy were prospectively monitored at a single center for complications and seizure outcome by using a proprietary database. Preintervention and postintervention data for patients 18 years of age and older, and with at least 1 year of follow-up, were analyzed, with specific attention to seizure control, complications, hormonal status, and death. RESULTS: Forty adult patients were found in the database (21 were women). The median HH volume was 0.54 cm(3). In 70% of patients, it was located inside the third ventricle, attached unilaterally and vertically to the hypothalamus (Delalande Type II). Most patients (26) underwent an endoscopic resection, 10 patients had a transcallosal or other type of open (pterional or orbitozygomatic) resection, and 4 patients chose GKS. Twenty-nine percent became seizure free in the long term, and overall a majority of patients (55%) reported at least > 90% seizure improvement. Only 3 patients were ultimately able to discontinue anticonvulsants, whereas most patients were taking an average of 2 antiepileptic drugs pre- and postoperatively. The only factor significantly correlated with seizure-free outcome was the absence of mental retardation. The HH volume, HH type, and amount of resection or disconnection were not correlated to seizure freedom. A total of 4 patients (10%) died, 2 immediately after surgery and 2 later. All of them had undergone a resection, as opposed to GKS, and still had seizures. Postoperatively, persistent neurological deficits were seen in 1 patient; 34% of patients had mild hormonal problems; and 59% experienced weight gain of at least 6.8 kg (average gain 12.7 kg). CONCLUSIONS: Surgical or GKS procedures in adults with HH provided seizure freedom in one-third of patients. The only significant favorable prognostic factor was the absence of mental retardation. The overall mortality rate was high, at 10%. Other important morbidities were persistent hormonal disturbances and weight gain.

EEG and video-EEG seizure monitoring has limited utility in patients with hypothalamic hamartoma and epilepsy.

PURPOSE: Hypothalamic hamartomas (HHs) are a malformation of the ventral hypothalamus and tuber cinereum, associated with gelastic seizures and epilepsy. We sought to determine the spectrum of electroencephalography (EEG) abnormalities in a large cohort of HH patients. METHODS: Data was collected for HH patients undergoing evaluation between 2003 and 2007. Data included seizure history, prior treatment, and results of diagnostic studies. After informed consent, data were entered into a database. KEY FINDINGS: We reviewed 133 HH patients. Mean age at time of data analysis was 15.7 years (59.4% male). Most patients had gelastic (77%) and/or complex partial seizures (58%). Records for 102 EEG studies on 73 patients were reviewed. Interictal epileptiform abnormalities were seen in 77%, localizing predominately to the temporal and frontal regions. Records for 104 video-EEG (VEEG) studies on 65 patients were reviewed. Of 584 gelastic seizures (GS) captured, no ictal EEG change was noted in 438 (75%). Of GS with localizing features, 89% suggested onset from the temporal and/or frontal regions. There were 160 complex partial seizures (CPS). For those with localizing features, 100% localized to the temporal and/or frontal head regions. EEG and VEEG findings correlated with the side of HH attachment. VEEG did not influence outcome. SIGNIFICANCE: EEG features in HH patients are diverse. The majority of gelastic seizures fail to demonstrate change in the EEG. The lack of EEG changes with many clinical seizures, and the false localization seen in those events with an ictal change suggest the utility of EEG is limited in the evaluation of these patients.

The histopathology of hypothalamic hamartomas: study of 57 cases.

Hypothalamic hamartomas (HHs) are rare developmental tumors that cause seizures or pituitary axis dysfunction, usually beginning in childhood. We analyzed HH tissue from 57 patients whose tumors were resected through recently developed transcallosal interforniceal and transventricular endoscopic surgical approaches. All cases were composed of abnormally distributed but cytologically normal neurons and glia, including fibrillary astrocytes and oligodendrocytes. Neuronal elements predominated in most cases, but a relative increase in astrocytic elements was seen with increasing age. All had various sized nodular foci of neurons as well as areas of diffusely distributed neurons with interspersed glial cells. Smaller neurons predominated, and most cases had only a few interspersed large ganglion cells. Immunohistochemistry demonstrated extensive production of synapse-associated proteins. Immunohistochemistry for phosphorylated and nonphosphorylated neurofilament and alpha-internexin demonstrated staining patterns consistent with mature neurons. In contrast to cortical dysplasia, atypical large ganglion-like balloon cells were almost never seen. In summary, although their number and distribution vary, mature smaller neurons were the most prominent and most consistent histologic feature of HH. Nodules of these small neurons were a universal feature of the microarchitecture of HH lesions associated with epilepsy. Characterization of these neurons may aid in understanding the mechanism of seizure development in HH.

Main trunk tibial neuropathies.

The authors present a retrospective study of 52 patients with main trunk tibial neuropathy. They found trauma and ischemia to be the most frequent causes, followed by tumors. These etiologic groups are underrepresented in the literature. Electrodiagnostic examination was helpful for localizing the lesion as well as for excluding S1 radiculopathies, with which tibial neuropathies can be confused clinically.