Abstract Purpose: To compare the sensitivities of MRI, FDG-PET and ictal/SPECT in localization of the epileptogenic substrate in patients with refractory temporal lobe epilepsy. Patients and methods: This study included 137 patients who received surgical treatment for intractable epilepsy. MRI, FDGPET and ictal 99mTc-HMPAO SPECT were retrospectively reviewed regarding their sensitivity in lateralization of the epileptogenic zone compared to video/EEG, pathological results and surgical outcome. Results: 104 MR-positive and 33 MR-negative patients were enrolled. In the MR-positive group, MRI, PET and ictal/SPECT were concordant to video/EEG in 72%, 83% and 73%, respectively. When compared to pathological diagnosis, they correctly lateralized the epileptogenic zone in 70%, 87%, and 73%, respectively. In patients with good surgical outcome, they correctly localized the epileptogenic zone in 79%, 88%, and 78%, respectively. In the MR-negative group, PET andictal/SPECT were concordant with video/EEG in 82% and 58%, respectively and matching with pathological diagnosis in 85% and 56%, respectively. Conclusion: PET is the most sensitive method in lateralization of the epileptogenic substrate. The use of MRI, PET and ictal/SPECT as a multimodality approach improves lateralization of the affected zone particularly in cases with negative MR findings and distinguishes patients who will benefit from surgery.

Background and methods: This study investigated the effects of sleep deprivation on total and partial (early and late) declarative memory and activation in the areas of the brain involved in these activities. The study included two experiments. Experiment 1 included 40 male residents of an orphanage aged 16–19 years, who were divided into four groups (n = 10 each) and subjected to total sleep deprivation, normal sleep, early-night sleep deprivation, or late-night sleep deprivation. Experiment 2 included eight students from the same institution who were divided into the same four groups (n = 2) as in experiment 1. Declarative memory was tested using lists of associated word pairs in both experiments, and activation of the relevant brain regions was measured before and after retrieval by single-photon emission computed tomography for subjects in experiment 2 only. Results: Students subjected to normal sleep had significantly higher scores for declarative memory retrieval than those subjected to total sleep deprivation (P = 0.002), early-night sleep deprivation (P = 0.005), or late-night sleep deprivation (P = 0.02). The left temporal lobe showed the highest rate of activity during memory retrieval after normal sleep, whereas the frontal, parietal, and right temporal lobes were more active after sleep deprivation. Conclusion: Both slow wave sleep and rapid eye movement sleep play an active role in consolidation of declarative memory, which in turn allows memory traces to be actively reprocessed and strengthened during sleep, leading to improved performance in memory recall.

Background and methods: This study investigated the effects of sleep deprivation on total and partial (early and late) declarative memory and activation in the areas of the brain involved in these activities. The study included two experiments. Experiment 1 included 40 male residents of an orphanage aged 16–19 years, who were divided into four groups (n = 10 each) and subjected to total sleep deprivation, normal sleep, early-night sleep deprivation, or late-night sleep deprivation. Experiment 2 included eight students from the same institution who were divided into the same four groups (n = 2) as in experiment 1. Declarative memory was tested using lists of associated word pairs in both experiments, and activation of the relevant brain regions was measured before and after retrieval by single-photon emission computed tomography for subjects in experiment 2 only. Results: Students subjected to normal sleep had significantly higher scores for declarative memory retrieval than those subjected to total sleep deprivation (P = 0.002), early-night sleep deprivation (P = 0.005), or late-night sleep deprivation (P = 0.02). The left temporal lobe showed the highest rate of activity during memory retrieval after normal sleep, whereas the frontal, parietal, and right temporal lobes were more active after sleep deprivation. Conclusion: Both slow wave sleep and rapid eye movement sleep play an active role in consolidation of declarative memory, which in turn allows memory traces to be actively reprocessed and strengthened during sleep, leading to improved performance in memory recall.

Background and methods: This study investigated the effects of sleep deprivation on total and partial (early and late) declarative memory and activation in the areas of the brain involved in these activities. The study included two experiments. Experiment 1 included 40 male residents of an orphanage aged 16–19 years, who were divided into four groups (n = 10 each) and subjected to total sleep deprivation, normal sleep, early-night sleep deprivation, or late-night sleep deprivation. Experiment 2 included eight students from the same institution who were divided into the same four groups (n = 2) as in experiment 1. Declarative memory was tested using lists of associated word pairs in both experiments, and activation of the relevant brain regions was measured before and after retrieval by single-photon emission computed tomography for subjects in experiment 2 only. Results: Students subjected to normal sleep had significantly higher scores for declarative memory retrieval than those subjected to total sleep deprivation (P = 0.002), early-night sleep deprivation (P = 0.005), or late-night sleep deprivation (P = 0.02). The left temporal lobe showed the highest rate of activity during memory retrieval after normal sleep, whereas the frontal, parietal, and right temporal lobes were more active after sleep deprivation. Conclusion: Both slow wave sleep and rapid eye movement sleep play an active role in consolidation of declarative memory, which in turn allows memory traces to be actively reprocessed and strengthened during sleep, leading to improved performance in memory recall.

Background and methods: This study investigated the effects of sleep deprivation on total and partial (early and late) declarative memory and activation in the areas of the brain involved in these activities. The study included two experiments. Experiment 1 included 40 male residents of an orphanage aged 16–19 years, who were divided into four groups (n = 10 each) and subjected to total sleep deprivation, normal sleep, early-night sleep deprivation, or late-night sleep deprivation. Experiment 2 included eight students from the same institution who were divided into the same four groups (n = 2) as in experiment 1. Declarative memory was tested using lists of associated word pairs in both experiments, and activation of the relevant brain regions was measured before and after retrieval by single-photon emission computed tomography for subjects in experiment 2 only. Results: Students subjected to normal sleep had significantly higher scores for declarative memory retrieval than those subjected to total sleep deprivation (P = 0.002), early-night sleep deprivation (P = 0.005), or late-night sleep deprivation (P = 0.02). The left temporal lobe showed the highest rate of activity during memory retrieval after normal sleep, whereas the frontal, parietal, and right temporal lobes were more active after sleep deprivation. Conclusion: Both slow wave sleep and rapid eye movement sleep play an active role in consolidation of declarative memory, which in turn allows memory traces to be actively reprocessed and strengthened during sleep, leading to improved performance in memory recall.

Objectives: The rate and impact of thyroglossal duct remnant (TGDR) visualization in patients with hypothyroidism after total thyroidectomy for differentiated thyroid carcinoma (DTC) have not yet been fully determined. The aim of this study was to assess the rate of TGDR visualization in post total thyroidectomy whole body scan (WBS) for DTC and to evaluate its impact on the outcome of I‑131 ablation. Methods: A total of 60 consecutive DTC patients (51 papillary thyroid Ca., and 9 Follicular thyroid Ca.), underwent total thyroidectomy, followed by WBS (using I‑131 in 28 patients and I‑123 in 32 patients), neck ultrasound (US), thyroglobulin (Tg) and Tg anti‑bodies (TgAb) assay after 40 days and subsequent I‑131 ablation. At 6 months later follow‑up I‑131 WBS, neck U/S, Tg and TgAb were performed following suspension of L‑thyroxine for 1‑month (thyroid stimulating hormone [TSH] >30 μIU/ml) in 53 patients and following recombinant human TSH stimulation in seven patients. Results: Of the studied 60 patients, 19/60 (31.7%) had a linear or focal radioactivity at the superior midline of the neck, suggesting TGDR (Group 1), and 41/60 (68.3%) had no uptake to suggest TGDR (Group 2). No significant difference regarding age, gender and histopathology between both groups. Neck US showed no evidence of thyroid tissue in the superior midline of the neck in both groups, and only a small or no residual thyroid tissue in patients of Group 1. There was a significant successful I‑131 ablation rate among patients of group 1 compared to group 2 (79% in Group 1 vs. 41.5% in Group 2) (P = 0.007). Conclusions: Thyroglossal duct remnant visualization on WBS of hypothyroid subjects after total thyroidectomy suggests presence of only a small or no residual functioning thyroid tissue at the thyroid bed and can predict a good response to I‑131 ablation.