Zelko Matkovic

Epilepsy Surgery for Pathologically Proven Hippocampal Sclerosis Provides Long‐term Seizure Control and Improved Quality of Life

Summary:  Purpose: To examine long‐term seizure and quality‐of‐life outcome in a homogeneous group of patients after temporal lobectomy with pathologically proven hippocampal sclerosis (HS). Previous research has had limited follow‐up (generally <2 years) and has grouped patients across multiple pathologies.

Seizure Frequency and Duration of Epilepsy are Not Risk Factors for Postoperative Seizure Outcome in Patients with Hippocampal Sclerosis

Summary: Purpose: Despite accurate localization of the seizure focus, not all patients are seizure free after temporal lobectomy. This study determined risk factors for seizure recurrence in patients with proven hippocampal sclerosis.

Non-invasive investigations successfully select patients for temporal lobe surgery

OBJECTIVES There is controversy regarding the need for invasive monitoring in the preoperative assessment of patients with temporal lobe epilepsy. The use of a series of non-invasive investigations in identifying the seizure focus is reported in 75 consecutive adults referred for epilepsy surgery. METHODS All had video-EEG monitoring using scalp electrodes, high resolution MRI, and neuropsychology assessment. Other investigations included volumetric MRI, PET, and ictal and interictal SPECT. The seizure focus was localised and surgery offered if MRI disclosed unilateral hippocampal atrophy or a foreign tissue lesion and other investigations were either concordant or not discordant. RESULTS In 68 patients the seizure focus was localised and three patients were inoperable. Sixty five patients have been offered surgery and 50 have undergone temporal lobe surgery and have a follow up of at least 12 months (mean 24 months). All had pathology: hippocampal sclerosis 34, dysembryoblastic neuroepithelial tumour six, cavernoma four, dysplasia two, low grade glioma two, ganglioglioma two. Thirty nine patients (78%) are seizure free postoperatively, 29/34 with hippocampal sclerosis and 10/16 with a foreign tissue lesion. Of the 11 patients with postoperative recurrent seizures, eight have a >90% reduction in seizure frequency and three have <90% reduction in seizure frequency but a worthwhile improvement. CONCLUSIONS Non-invasive investigations successfully select most patients for temporal lobe surgery.

The Liverpool Adverse Events Profile: Relation to AED Use and Mood

Summary:  Purpose: The Liverpool Adverse Events Profile (LAEP) is used as a systematic measure of adverse effects from antiepileptic drugs (AEDs). This study evaluated LAEP in newly diagnosed seizure patients, and examined the relation between LAEP, anxiety, and depression.

Preoperative evaluation for temporal lobe surgery

Temporal lobe epilepsy (TLE), the most common form of partial epilepsy in adults is often refractory to medical treatment and in these patients epilepsy surgery is considered. Successful surgery is dependent on accurate localisation and lateralisation of the epileptogenic zone. The preoperative evaluation involves a series of assessments and investigations including detailed clinical history, interictal EEG, video-EEG monitoring, MRI, PET, SPECT, and neuropsychology and neuropsychiatric assessment. The role of each of these investigations and assessments in the preoperative evaluation is discussed. Advanced MR techniques including magnetic resonance spectroscopy, MR diffusion and MR perfusion have recently been assessed and are likely to enhance the pre-surgical evaluation of patients with TLE.The surgical outcome and preoperative investigations performed of 80 consecutive patients who underwent temporal lobe surgery between 1993 and 2002 at Royal Melbourne Hospital were reviewed. All patients had MRI, video-EEG monitoring and neuropsychology assessment and 56% a PET scan. During a mean follow-up of 5.9 years 75% had Class 1 outcome, 22% non-Class 1 outcome and 3% were lost to follow-up. The results of preoperative investigations were correlated with outcome. For interictal EEG, seizure semiology, ictal EEG, PET and neuropsychology assessment the surgical outcome of patients in whom results were concordant to side of surgery was compared with those discordant or non-lateralising. There was no significant difference. In 78 of 80 patients MRI revealed mesial temporal sclerosis or a foreign tissue lesion. The outcome was no different between these two groups. Results suggest that in patients with unilateral temporal lobe lesion on MRI and where ictal EEG is either concordant or non-lateralising, other investigations including PET, provide little additional prognostic information.

Surgery for suspected neurogenic thoracic outlet syndromes: a follow up study

OBJECTIVES To assess the outcome of surgical treatment for thoracic outlet syndrome (TOS), and to compare the outcome in patients with and without an underlying cervical rib. METHODS a heterogeneous group of 40 patients (33 women, seven men; aged 22–62 years) were evaluated 3 months to 20 years after surgery for suspected neurogenic TOS. Forty nine operations had been performed: cervical ribs were removed in 23 patients, together with fibrous band excision in nine. In the 17 without a cervical rib the thoracic outlet was decompressed by resection of the first thoracic rib in nine, and by other operations in eight. RESULTS After surgery patients reported improved pain (33/36), sensory disturbance (30/35), hand muscle strength (14/27), and hand function (23/34). Postoperatively TOS recurred in two, and symptoms continued to progress in three patients in whom other diagnoses eventually emerged. Surgical complications were recorded in 10 patients, but were transient and did not result in permanent symptomatic sequelae. CONCLUSIONS Surgical treatment of suspected neurogenic TOS relieves pain and sensory disturbance (90%), but is less effective for muscle weakness (50%). Surprisingly, surgery relieved sensory and motor abnormalities to a similar degree in patients both with and without a cervical rib. Ideally, patients require early operation to forestall permanent hand muscle denervation, but, our retrospective analysis fails to identify any single preoperative diagnostic criterion for TOS, particularly in patients lacking a radiographic cervical rib.

The diagnostic value of oral lacerations and incontinence during convulsive "seizures".

Purpose: Oral lacerations and urinary incontinence have long been considered useful clinical features for the diagnosis of epileptic seizures; however, both are also reported in patients with psychogenic nonepileptic seizures (PNES). The aims of the study were (1) to investigate whether the presence and nature of oral lacerations or incontinence during convulsive seizures of patients with epilepsy differed from those with PNES, and (2) whether the side of the oral laceration has any correlation with the epilepsy syndrome or lateralization.

Convulsive nonepileptic seizures have a characteristic pattern of rhythmic artifact distinguishing them from convulsive epileptic seizures.

Summary:  Purpose: Approximately 30% of patients admitted for video‐EEG monitoring have psychogenic nonepileptic seizures (PNES). Differentiation of “convulsive” PNES from convulsive seizures can be difficult. The EEG often displays rhythmic movement artifact that may resemble seizure activity and confound the interpretation. We sought to determine whether time–frequency mapping of the rhythmic EEG artifact during “convulsive” PNES reveals a pattern that differs from that of epileptic seizures.

MRI-identified pathology in adults with new-onset seizures

Objective: To determine the frequency and nature of potentially epileptogenic lesions on MRI in adults with new-onset seizures. Methods: We prospectively studied a consecutive series of 993 patients (597 males [61%]; mean [SD] age: 42.2 [18.8] years, range 14.3–94.3 years) who presented to an adult First Seizure Clinic over a 10-year period. The MRI scans, performed clinically on 3- and 1.5-tesla scanners, were reviewed for their diagnostic yield, nature of abnormalities, and their association with abnormal electrical activity on EEG. Results: MRI scans were acquired in 764 patients (77%); potentially epileptogenic lesions were detected in 177 (23%). The frequency of potentially epileptogenic lesions was higher in patients who were diagnosed as having an epileptic seizure (28%) than in those with a nonepileptic event (8%) (p < 0.001), and highest in those who had focal-onset seizures (53%) (p < 0.001). The most common lesion type in patients with focal seizures was gliosis or encephalomalacia (49%). Other common lesion types were tumors (15%), cavernomas (9%), and mesial temporal sclerosis (9%). Abnormal MRI and EEG were concordant in 18% of patients, with EEG being normal in 55% of patients with epileptogenic lesions. Conclusions: MRI reveals potentially epileptogenic lesions in a minority of patients with a newly diagnosed seizure disorder. Lesions are most common in patients who have experienced focal seizures. The presence of a potentially epileptogenic MRI lesion did not influence the chance of having an abnormal EEG.

Tiagabine-induced generalised non convulsive status epilepticus in patients with lesional focal epilepsy

PURPOSE To report 3 cases with focal lesional epilepsy that had non-convulsive status epilepticus (NCSE) induced by treatment with tiagabine (TGB) and review the previously published cases. Drugs that enhance GABAnergic transmission are recognised to promote absence seizures in patients with generalised epilepsy syndromes and may on occasions even induce NCSE. However, that TGB can also induce NCSE in focal lesional epilepsy is not widely recognised in clinical practice. METHOD The clinical history, EEG and MRI findings were reviewed in 3 patients with lesional focal epilepsy who presented to our epilepsy programs over a 12 month period with TGB-induced NCSE. All previously reported cases in the English medical literature were reviewed. RESULTS The three patients had longstanding complex partial and secondarily generalised seizures refractory to multiple different anti-epileptic drugs. In two cases, MRI demonstrated a focal malformation of cortical development in the left parieto-occipital region and in the third left mesial temporal sclerosis. Following commencement of TGB in one patient and dose escalation in two, prolonged episodes of confusion and poor responsiveness were noted. Prolonged EEG monitoring demonstrated continuous high amplitude, generalised, 2-4 Hz delta activity with intermingled spikes during the episodes of unresponsiveness, consistent with NCSE. The clinical and EEG activity normalised following the administration of IV clonazepam followed by dose reduction or withdrawal of the TGB. Eleven previously reported cases of patients with partial epilepsy and a focal underlying lesion on MRI were identified, all of whom had similar features to that seen in our cases. CONCLUSIONS These cases illustrate that TGB may induce generalised NCSE in patients with focal lesional epilepsy, in addition to those with generalised syndromes. We hypothesise that patients may have developed an acquired alteration in the sensitivity of their thalamocortical circuitry that renders them more sensitive to the effects of drugs that enhance GABAnergic activity.