Hippocampal deformation mapping in MRI-negative PET-positive temporal lobe epilepsy

Objectives: To compare hippocampal surface structure, using large deformation high dimensional mapping (HDM-LD), in subjects with temporal lobe epilepsy (TLE) with (HS+ve) and without (HS−ve) hippocampal sclerosis.

Methods: The study included 30 HS−ve subjects matched with 30 HS+ve subjects from the previously reported epilepsy patient cohort. To control for normal right–left asymmetries of hippocampal surface structure, subjects were regrouped based on laterality of onset of epileptic seizures and presence of HS. Gender ratio, age, duration of epilepsy and seizure frequency were calculated for each of the four groups. Final HDM-LD surface maps of the right and left TLE groups were compared to define differences in subregional hippocampal involvement within the groups.

Results: There were no significant differences in comparisons of the left TLE (left HS−ve compared with HS+ve) or right TLE (right HS−ve compared with HS+ve) groups with respect to age, duration of epilepsy or seizure severity scores. HDM-LD maps showed accentuated surface changes over the lateral hippocampal surface, in the region of the Sommer sector, in the hippocampi affected by HS. However, HS−ve hippocampi showed maximal surface changes in a different pattern, and did not involve the region of Sommer sector.

Conclusion: We conclude that differences in segmental volume loss between the HS−ve and HS+ve groups are suggestive that the underlying pathophysiology of hippocampal changes in the two groups is different, and not related to chronic seizure duration or severity.

Asymmetry in volume between dominant and nondominant upper limbs in young tennis players

This study aimed at demonstrating the asymmetry in volume between the dominant and nondominant upper limbs in tennis players, controlled for maturity status. Upper limb volumes on both sides were calculated in 72 tennis players and 84 control subjects, using the truncated cone method. The participants’ maturity status was determined using the predicted age at peak height velocity (PHV). The results showed significant larger side-to-side asymmetry in volume in tennis groups than
in control groups. These findings suggested that, even before PHV, specific-sport adaptations occurred in the dominant upper limb in tennis players.

Anesthetic induction for ECT with etomidate is associated with longer seizure duration than thiopentone.

Many factors influence seizure duration associated with electroconvulsive therapy (ECT). This is a chart review study to assess seizure duration measured with both electroencephalography and electromyography after anesthetic induction with either thiopentone or etomidate. Thirty-seven patients receiving ECT for depression were entered into the study, and a pair of seizures was measured from each patient. Alternate induction agents were used in sequential pairings, and the study was controlled for interval between seizures, laterality, and percent energy. Etomidate was associated with a significantly (p = 0.0002, F = 15.84, df = 1, analysis of variance) longer seizure duration (mean = 34.43 s, SD = 16.06) than thiopentone (mean = 21.73 s, SD = 9.33).

Simulated hyperopic anisometropia and reading, visual information processing, and reading-related eye movement performance in children.

Purpose: This study investigated the impact of simulated hyperopic anisometropia and sustained near work on performance of academic-related measures in children.
Methods: Participants included 16 children (mean age: 11.1 ± 0.8 years) with minimal refractive error. Academic-related outcome measures included a reading test (Neale Analysis of Reading Ability), visual information–processing tests (Coding and Symbol Search subtests from the Wechsler Intelligence Scale for Children), and a reading-related eye movement test (Developmental Eye Movement test). Performance was assessed with and without 0.75 diopters of simulated monocular hyperopic defocus (administered in a randomized order), before and after 20 minutes of sustained near work. Unilateral hyperopic defocus was systematically assigned to either the dominant or nondominant sighting eye to evaluate the impact of ocular dominance on any performance decrements.
Results: Simulated hyperopic anisometropia and sustained near work both independently reduced performance on all of the outcome measures (P < 0.001). A significant interaction was also observed between simulated anisometropia and near work (P < 0.05), with the greatest decrement in performance observed during simulated anisometropia in combination with sustained near work. Laterality of the refractive error simulation (ocular dominance) did not significantly influence the outcome measures (P > 0.05). A reduction of up to 12% in performance was observed across the range of academic-related measures following sustained near work undertaken during the anisometropic simulation.
Conclusions: Simulated hyperopic anisometropia significantly impaired academic-related performance, particularly in combination with sustained near work. The impact of uncorrected habitual anisometropia on academic-related performance in children requires further investigation. © 2014 The Association for Research in Vision and Ophthalmology, Inc.

Facilitating effects of transcranial direct current stimulation on motor imagery brain-computer interface with robotic feedback for stroke rehabilitation

OBJECTIVE: To investigate the efficacy and effects of transcranial direct current stimulation (tDCS) on motor imagery brain-computer interface (MI-BCI) with robotic feedback for stroke rehabilitation. DESIGN: A sham-controlled, randomized controlled trial. SETTING: Patients recruited through a hospital stroke rehabilitation program. PARTICIPANTS: Subjects (N=19) who incurred a stroke 0.8 to 4.3 years prior, with moderate to severe upper extremity functional impairment, and passed BCI screening. INTERVENTIONS: Ten sessions of 20 minutes of tDCS or sham before 1 hour of MI-BCI with robotic feedback upper limb stroke rehabilitation for 2 weeks. Each rehabilitation session comprised 8 minutes of evaluation and 1 hour of therapy. MAIN OUTCOME MEASURES: Upper extremity Fugl-Meyer Motor Assessment (FMMA) scores measured end-intervention at week 2 and follow-up at week 4, online BCI accuracies from the evaluation part, and laterality coefficients of the electroencephalogram (EEG) from the therapy part of the 10 rehabilitation sessions. RESULTS: FMMA score improved in both groups at week 4, but no intergroup differences were found at any time points. Online accuracies of the evaluation part from the tDCS group were significantly higher than those from the sham group. The EEG laterality coefficients from the therapy part of the tDCS group were significantly higher than those of the sham group. CONCLUSIONS: The results suggest a role for tDCS in facilitating motor imagery in stroke.

Vein diameter for peripherally inserted cathether insertion: a scoping review

Background: The risk of venous thromboembolism (VTE) may be reduced if a vein of appropriate diameter is used forperipherally inserted central catheter (PICC) insertion. However, clinicians may have predilections to cannulate certainvein types and use particular insertion sites (eg, right or left arm) and therefore do not necessarily assess all veinsavailable to determine the most optimal vessel to introduce a catheter. It is important that clinicians have anunderstanding of the diameter of veins used for PICC insertion and the effect of patient factors such as hand dominanceon vein size to determine whether their clinical practice is appropriate.

Methods: A scoping review of published literature was performed to determine existing knowledge regarding thediameters of veins used for PICC insertion and the influence of patient factors such as hand dominance and laterality(left or right arm) on vein size.

Results: There was limited published research about the diameters of the basilic, brachial, and cephalic veins at themidupper arm, with only 6 studies identified. Three of the 6 selected articles focused on vein diameter measurement toinform arteriovenous fistula development. Only 1 study included participants undergoing PICC insertion. Scant researchexamined the effect of laterality on vein diameter and 1 study was identified that reported the influence of handdominance or vein type on the diameter of veins used for PICC insertion.

Conclusions: This review found that there is a paucity of studies that have examined the veins used for PICC insertion.Nevertheless, it appears that the basilic vein has the largest diameter (with smaller brachial and cephalic veins),although this is not always the case. Laterality and hand dominance does not seem to influence vein diameter. Furtherresearch about the vasculature used for PICC insertion is needed to inform clinical practice.