High-density electric source imaging patterns and outcomes following temporal lobectomy in patients with hippocampal sclerosis

OBJECTIVE

The objective of this study was to ascertain specific patterns of electrical source imaging (ESI) that are associated with a good surgical outcome (no seizure recurrence) using 256-channel high-density (HD) electroencephalography (EEG) in patients with temporal lobe epilepsy with hippocampal sclerosis (TLE-HS) who underwent temporal lobectomy.

METHODS

Adult patients (age ≥ 18 years) were prospectively recruited from September 2016 to May 2020 at the authors' center. All patients underwent phase I presurgical evaluation and were subsequently advised to proceed with surgery based on consensus from a multidisciplinary epilepsy conference, without knowing HD-ESI results. All recruited patients were followed for at least 12 months after surgery. The outcome of interest was a status of no seizure recurrence, which was assessed at the end of the study. The association between ESI patterns and outcome was assessed using the chi-square or Fisher exact test. Associated p values as well as odds ratios and 95% CIs were reported. The diagnostic performance of the significant pattern associated with the outcome was also evaluated.

RESULTS

Fifty-eight patients with known predictors for either good or worse surgical outcomes were recruited. The mean postoperative follow-up period was 33.34 (SD 13.88) months. Forty-seven patients had sufficient interictal epileptiform discharges for HD-ESI analysis. Thirteen of these 47 patients experienced seizure recurrence. The most common source localizations were at Brodmann area (BA) 20 (inferior temporal area) and BA 21 (middle temporal area). A specific ESI pattern of BA 21 without extratemporal sources was significantly associated with no seizure recurrence (p = 0.047). This pattern had a high positive predictive value of 100% and false-positive rate of 0% associated with no seizure recurrence following the surgery.

CONCLUSIONS

A specific ESI pattern that was highly associated with no seizure recurrence following surgery was demonstrated by a 256-channel HD-EEG. If this pattern can be reproducibly proven in further studies, some TLE-HS patients may be able to proceed with surgery without further investigations.

Serum proinsulin levels as peripheral blood biomarkers in patients with cognitive impairment

Insulin has long been associated with dementia. Insulin affecting the clearance of amyloid-β peptide and phosphorylation of tau in the CNS. Proinsulin is a precursor of insulin and its elevated serum levels are associated with peripheral insulin resistance that may reduce brain insulin levels. Our study aimed to assess differences in serum proinsulin levels between normal and cognitive impairment groups. Prospective recruitment of elderly participants was initiated from October 2019 to September 2023. Patients were divided into "cognitive impairment" and "normal cognition" group. All participants had blood drawn and serum proinsulin was measured at baseline and 12 months. Neurocognitive testing was performed every 6 months. A total of 121 participants were recruited. Seventy-seven were in the normal cognition group and 44 in the cognitive impairment group. The glycemic control and prevalence of diabetes type 2 was similar between groups. Baseline serum proinsulin levels were higher in the cognitively impaired group compared to the normal group at baseline (p = 0.019) and correlated with worse cognitive scores. We identified cognitive status, age, and BMI as potential factors associated with variations in baseline proinsulin levels. Given the complex interplay between insulin and dementia pathogenesis, serum biomarkers related to insulin metabolism may exhibit abnormalities in cognitive impaired patients. Here we present the proinsulin levels in individuals with normal cognitive function versus those with cognitive impairment and found a significant difference. This observation may help identifying non-diabetic patients suitable for treatment with novel AD drugs that related to insulin pathway.

Prospective evaluation of plasma phosphorylated tau in a real-life memory clinic in Thailand

INTRODUCTION

Despite the substantial accuracy of plasma p-tau in diagnosing Alzheimer's disease (AD) in research cohorts, data on real-life memory clinic patients are lacking.

METHODS

Memory clinic patients at their early symptomatic stages were prospectively enrolled to undergo routine clinical assessment, plasma p-tau181 quantification (Simoa), amyloid and tau-positron emission tomography (PET). The diagnostic performance of plasma p-tau181, neurocognitive specialists, and regional tau-PET were compared head-to-head using amyloid-PET as the reference standard.

RESULTS

Plasma p-tau181 has the area under the curve (AUC), sensitivity, specificity, and accuracy of 0.84 (95% confidence interval [CI] 0.73-0.94), 0.80 (95% CI 0.64-0.90), 0.75 (95% CI 0.51-0.90), and 0.78 (95% CI 0.65-0.88) for detecting amyloid-PET positivity in early symptomatic patients, respectively. The AUC of clinical diagnosis and tau-PET were 0.70 (95% CI 0.56-0.85) and 0.88 (95% CI 0.79-0.97), respectively.

DISCUSSION

Plasma p-tau181 also performed well in real-life memory clinic settings and its role in clinical practice is supported.

Nuclear imaging for localization and surgical outcome prediction in epilepsy: A review of latest discoveries and future perspectives

Background

Epilepsy is one of the most common neurological disorders. Approximately, one-third of patients with epilepsy have seizures refractory to antiepileptic drugs and further require surgical removal of the epileptogenic region. In the last decade, there have been many recent developments in radiopharmaceuticals, novel image analysis techniques, and new software for an epileptogenic zone (EZ) localization.

Objectives

Recently, we provided the latest discoveries, current challenges, and future perspectives in the field of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) in epilepsy.

Methods

We searched for relevant articles published in MEDLINE and CENTRAL from July 2012 to July 2022. A systematic literature review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis was conducted using the keywords "Epilepsy" and "PET or SPECT." We included both prospective and retrospective studies. Studies with preclinical subjects or not focusing on EZ localization or surgical outcome prediction using recently developed PET radiopharmaceuticals, novel image analysis techniques, and new software were excluded from the review. The remaining 162 articles were reviewed.

Results

We first present recent findings and developments in PET radiopharmaceuticals. Second, we present novel image analysis techniques and new software in the last decade for EZ localization. Finally, we summarize the overall findings and discuss future perspectives in the field of PET and SPECT in epilepsy.

Conclusion

Combining new radiopharmaceutical development, new indications, new techniques, and software improves EZ localization and provides a better understanding of epilepsy. These have proven not to only predict prognosis but also to improve the outcome of epilepsy surgery.

Brain perfusion single photon emission computed tomography abnormality in MRI-negative stroke-like patients post COVID-19 vaccination

Stroke-like symptoms after COVID-19 vaccination was thought to be functional if there was no anatomical image abnormality. We aimed to analyze brain perfusion changes in these patients. A case-control study of brain perfusion single photon emission computed tomography (SPECT) of 12 vaccinated patients with left-sided stroke-like symptoms were compared with 12 age- and gender-matched normal interictal brain SPECTs using voxel-based analysis. Significant hyperperfusion was seen on the right side in postcentral, inferior parietal, mid temporal, parahippocampal, and caudate regions, and on the left side in the thalamus, hippocampus, and mid temporal areas. In addition, there were hypoperfused bilateral superior frontal gyri and right mid/posterior cingulate cortex (Family-wise-error corrected p-values  < .05). Both hypoperfusion and hyperperfusion in the brain are demonstrated. We hypothesize that these findings might be the result of the functional neurological disorder. However, based on other previous studies, circulating spike protein in the patients' plasma early after vaccination might also be the cause.

Brain laterality evaluated by F-18 fluorodeoxyglucose positron emission computed tomography in autism spectrum disorders

Background and rationale

Autism spectrum disorder (ASD) is a neuropsychiatric disorder that has no curative treatment. Little is known about the brain laterality in patients with ASD. F-18 fluorodeoxyglucose positron emission computed tomography (F-18 FDG PET/CT) is a neuroimaging technique that is suitable for ASD owing to its ability to detect whole brain functional abnormalities in a short time and is feasible in ASD patients. The purpose of this study was to evaluate brain laterality using F-18 FDG PET/CT in patients with high-functioning ASD.

Materials and methods

This case-control study recruited eight ASD patients who met the DSM-5 criteria, the recorded data of eight controls matched for age, sex, and handedness were also enrolled. The resting state of brain glucose metabolism in the regions of interest (ROIs) was analyzed using the Q.Brain software. Brain glucose metabolism and laterality index in each ROI of ASD patients were compared with those of the controls. The pattern of brain metabolism was analyzed using visual analysis and is reported in the data description.

Results

The ASD group’s overall brain glucose metabolism was lower than that of the control group in both the left and right hemispheres, with mean differences of 1.54 and 1.21, respectively. We found statistically lower mean glucose metabolism for ASD patients than controls in the left prefrontal lateral (Z = 1.96, p = 0.049). The left laterality index was found in nine ROIs for ASD and 11 ROIs for the control. The left laterality index in the ASD group was significantly lower than that in the control group in the prefrontal lateral (Z = 2.52, p = 0.012), precuneus (Z = 2.10, p = 0.036), and parietal inferior (Z = 1.96, p = 0.049) regions.

Conclusion

Individuals with ASD have lower brain glucose metabolism than control. In addition, the number of ROIs for left laterality index in the ASD group was lower than control. Left laterality defects may be one of the causes of ASD. This knowledge can be useful in the treatment of ASD by increasing the left-brain metabolism. This trial was registered in the Thai Clinical Trials Registry (TCTR20210705005).

Cutaneous Management after Extravasation of High-Concentrated Amino Acid Solution Administered for Renal Protection in PRRT

High-concentrated amino acid solution is used to protect the kidneys during peptide receptor radionuclide therapy (PPRT) in patients with neuroendocrine tumors (NETs). Extravasation of the solution can cause cutaneous complications. In this study, we described a 66-year-old man with metastatic medullary thyroid cancer and a 32-year-old woman with metastatic pancreatic NET who developed cutaneous lesions caused by the extravasation of an amino acid solution (25 g of lysine and 25 g of arginine in 1 L of normal saline) during PRRT with [¹⁷⁷Lu]Lu-DOTA-TATE. Both were treated conservatively, and these cutaneous lesions gradually improved. The patient with metastatic pancreatic NET rejected the amino acid infusion in subsequent cycles of PRRT and therefore received [¹⁷⁷Lu]Lu-DOTA-TATE alone, and her serum creatinine level and estimated glomerular filtration rate (eGFR) remained normal for 2 months after the last treatment. These two cases revealed cutaneous complications resulting from high-concentrated amino acid solution during PRRT because of hyperosmolarity. Health care providers should be aware of this complication to ensure its prevention and appropriate management. Preserved renal function was demonstrated after [¹⁷⁷Lu]Lu-DOTA-TATE treatment in the absence of the infusion of a high-concentrated amino acid solution. However, long-term follow-up of renal function is suggested.

Prolonged migraine aura resembling ischemic stroke following CoronaVac vaccination: an extended case series

Background

After the initiation of the COVID-19 vaccination program in Thailand, thousands of patients have experienced unusual focal neurological symptoms. We report 8 patients with focal neurological symptoms after receiving inactivated virus vaccine, CoronaVac.

Case series

Patients were aged 24–48 years and 75% were female. Acute onset of focal neurological symptoms occurred within the first 24 h after vaccination in 75% and between 1-7d in 25%. All presented with lateralized sensory deficits, motor deficits, or both, of 2–14 day duration. Migraine headache occurred in half of the patients. Magnetic resonance imaging of the brain during and after the attacks did not demonstrate any abnormalities suggesting ischemic stroke. All patients showed moderately large regions of hypoperfusion and concurrent smaller regions of hyperperfusion on SPECT imaging while symptomatic. None developed permanent deficits or structural brain injury.

Discussions

Here, we present a case series of transient focal neurological syndrome following Coronavac vaccination. The characteristic sensory symptoms, history of migraine, female predominant, and abnormal functional brain imaging without structural changes suggest migraine aura as pathophysiology. We propose that pain related to vaccine injection, component of vaccine, such as aluminum, or inflammation related to vaccination might trigger migraine aura in susceptible patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01385-0.

Alterations of regional cerebral glucose metabolism using18F-fluorodeoxyglucose positron-emission tomography/computed tomography and electroencephalography analysis during mindfulness breathing in Anapanasati meditation: A preliminary analysis

Anapanasati is a core meditation of a breath-centered practice in the Buddhist Theravada tradition, which may have some neurological mechanism effects on the brain. To gain insight into the neurological mechanisms involved in Anapanasati meditation, we measured the alterations of regional cerebral glucose metabolism during Anapanasati meditation using positron-emission tomography/computed tomography (PET/CT) and electroencephalography (EEG) analysis. This prospective study was conducted in six right-handed volunteer participants (two men, four women; aged: 32–67 years) who underwent¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET/CT scans to compare the alterations of regional cerebral glucose metabolism during normal consciousness and Anapanasati meditation states. Spectral EEG analysis was performed throughout the investigations. Statistical parametric mapping was used for the¹⁸F-FDG PET/CT image analyses. The visual analysis demonstrated moderate-to-marked increased metabolism in posterior cingulate cortex in all six patients, while mild-to-moderate increased uptake in the whole frontal lobe was also observed in four patients and precuneus in four patients. Meanwhile, the semiquantitative analysis yielded an increase of regional cerebral glucose metabolism in the right mid-to-posterior cingulate gyrus (P < 0.000), with visible alpha waves on the frontal of the EEG findings. Our semiquantitative analysis showed a significantly increased metabolism only in the posterior cingulate cortex, but visually, there was also an increased metabolism in the whole frontal lobe in most of the patients correlating with EEG findings.

Impact of reconstruction parameters on lesion detection and localization in joint ictal/inter-ictal SPECT reconstruction

PURPOSE

Previously, a joint ictal/inter-ictal SPECT reconstruction was proposed to reconstruct a differential image representing the change of brain SPECT image from an inter-ictal to an ictal study. The so-called joint method yielded better performance for epileptic foci localization than the conventional subtraction method. In this study, we evaluated the performance of different reconstruction settings of the joint reconstruction of ictal/inter-ictal SPECT data, which creates a differential image showing the difference between ictal and inter-ictal images, in lesion detection and localization in epilepsy imaging.

METHODS

Differential images reconstructed from phantom data using the joint and the subtraction methods were compared based on lesion detection performance (channelized Hotelling observer signal-to-noise ratio (SNR_CHO) averaged across four lesion-to-background contrast levels) at the optimal iteration. The joint-initial method which was the joint method that was initialized by the subtraction method at optimal iteration was also used to reconstruct differential images. These three methods with respective optimal iteration and the subtraction method with four iterations were applied to epileptic patient datasets. A human observer lesion localization study was performed based on localization receiver operating characteristic (LROC) analysis.

RESULTS

From the phantom study, at their respective optimal iteration, the joint method yielded an improvement in lesion detection performance over the subtraction method of 26%, which increased to 145% when using the joint-initial method. From the patient study, the joint-initial method yielded the highest area under the LROC curve as compared with those of the joint and the subtraction methods with optimal iteration and with 4 iterations (0.44 vs 0.41, 0.39 and 0.36, respectively).

CONCLUSIONS

In lesion detection and localization, the joint method at optimal iteration outperformed the subtraction method at optimal iteration and at iteration typically used in clinical practice. Furthermore, initialization by the subtraction method improved the performance of the joint method.

Acute prolonged motor aura resembling ischemic stroke after COVID - 19 vaccination (CoronaVac): the first case report

Background

We report the first case of a patient who suffered transient focal neurological deficit mimicking stroke following CoronaVac vaccination. However, instead of an ischemic stroke, motor aura was suspected.

Case presentations

A 24 year-old Thai female presented with left hemiparesis fifteen minutes after receiving CoronaVac. She also had numbness of her left arm and legs, flashing lights, and headaches. On physical examination, her BMI was 32.8. Her vital signs were normal. She had moderate left hemiparesis (MRC grade III), numbness on her left face, arms, and legs. Her weakness continued for 5 days. A brain CT scan was done showing no evidence of acute infarction. Acute treatment with aspirin was given. MRI in conjunction with MRA was performed in which no restricted diffusion was seen. A SPECT was performed to evaluate the function of the brain showing significant hypoperfusion of the right hemisphere. The patient gradually improved and was discharged.

Discussions

In this study, we present the first case of stroke mimic after CoronaVac vaccination. After negative imaging studies had been performed repeatedly, we reach a conclusion that stroke is unlikely to be the cause. Presumably, this phenomenon could possibly have abnormal functional imaging study. Therefore, we believed that it might be due to cortical spreading depression, like migraine aura, which we had conducted a literature review.

Effects of vitamin D and calcium supplementation on bone mineral density among Thai youth using daily HIV pre-exposure prophylaxis

INTRODUCTION

Tenofovir disoproxil fumarate with emtricitabine (TDF/FTC) is used for HIV pre-exposure prophylaxis (PrEP). TDF may affect bone mineral density (BMD), particularly in youth who are at a stage of peak bone mass accrual. The objective of this study was to evaluate the effect of vitamin D and calcium supplementation on BMD among Thai youth receiving daily oral PrEP.

METHODS

This open-label randomized trial was conducted in male youth aged between 15 and 24 years. Participants were randomized to Arm A who received once-daily TDF/FTC plus vitamin D3 and calcium supplementation with meals twice daily (400 units of vitamin D3 and 1200 mg of elemental calcium/day) or Arm B who received once-daily TDF/FTC only. PrEP users were defined as taking at least two tablets/week (tenofovir-diphosphate level of >350 fmol/punch). Adherence to vitamin D/calcium supplementation was defined as self-reported adherence of >50%. Lumbar spine (L2-L4) BMD (LSBMD) was evaluated by dual-energy X-ray absorptiometry scan zero and six months after PrEP initiation.

RESULTS

From March 2019 to March 2020, 100 youth were enrolled. Baseline characteristics between the two arms were similar. Median (IQR) age was 18 (17 to 20) years. At entry, median (IQR) LSBMD z-score was -0.8 (-1.5 to -0.3), 17% had low LSBMD (Z-score < -2). The median amount of calcium intake from nutritional three-day recall was 167 (IQR 94 to 272) mg/day, 39% of participants had vitamin D deficiency, defined as 25(OH)D levels <20 IU/mL. At six months, 79 participants were evaluated. Of these, 42 (52%) were PrEP takers and 25 of 38 (66%) of arm A participants had good adherence to vitamin D/calcium supplementation. Significantly higher proportions of youth in arm A compared to arm B had >3% increase in LSBMD at month 6 compared to baseline (67.6% vs. 42.9% respectively; p = 0.03). There were significantly higher increases in LSBMD among youth with vitamin D deficiency who were supplemented; arm A + 0.05 (0 to 0.05) compared to arm B + 0.03 (-0.1 to 0.03), p = 0.04.

CONCLUSIONS

Increases in LSBMD over six months among youth using PrEP who received vitamin D/calcium supplementation was greater than those not supplemented. Long-term follow-up should be considered to explore long-term outcomes.

Early prediction of donepezil cognitive response in Alzheimer's disease by brain perfusion single photon emission tomography

Currently, there is no effective means to evaluate donepezil response. We evaluated brain perfusion change at 4 h after donepezil administration (4 h DNPZ) to predict cognitive responses after 6 months of medication. CERAD neuropsychological assessment battery was used to define cognitive response at 6 months. We compared 4 h DNPZ to baseline single photon emission tomography (SPECT) by statistical parametric mapping to identify perfusion changes in responders (N = 16) and non-responders (N = 7). In responders, there were significant relatively increase in perfusion in left parietal lobe (BA39, 7, 1), right superior frontal gyrus (BA6) and right middle occipital gyrus (BA39). In the non-responders, perfusion was relatively increase in the left parietal lobe (BA39) only. In an explorative analysis, we found a significant correlation between perfusion changes in right BA6 and CERAD score changes at 6 months. Different SPECT perfusion changes at 4 h after donepezil administration were demonstrated in the group of responders and non-responders with potential correlation with CERAD score change. Thus, 4 h DNPZ brain perfusion SPECT can be used to predict donepezil response at 6 months.

Finding the best effective way of treatment for rapid I-131 turnover Graves' disease patients: A randomized clinical trial

BACKGROUND

Rapid I-131 turnover Graves' disease patients have low cure rate. We aimed to compare cure percentage at 12 months among 3 treatment doses of I-131 with or without lithium carbonate (LiCO3) in rapid turnover Graves' disease patients.

METHODS

Sixty Graves' disease patients referred for radioactive iodine treatment were randomised into three arms of treatment: Group A, 3.7 MBq I-131/g thyroid plus 600 mg/day LiCO3, Group B, 5.55 MBq I-131/g plus 600 mg/day LiCO3, and Group C, 7.4 MBq I-131/g without LiCO3. Data were collected at baseline, 3, 6, 9, and 12 months. The primary endpoint were cure rates (percentage of euthyroid or hypothyroid) at 12 months. Pairwise comparisons were made across 3 groups using an equality of proportions test. The secondary endpoint, the odds of cure over the total follow-up for group B and C versus group A, was analyzed using generalized estimating equation (GEE). Side effects of I-131 and LiCO3 treatment were evaluated at 1 to 2 weeks after treatment.

RESULTS

The cure rate at 12 months was 45% (9/20) for group A, 60% (12/20) for group B and 80% (16/20) for group C. The mean difference in proportion cured at 12 months between group C and group A was 35 (7.0 to 66.8)%; P-value = .02. There was a statistically significant difference between cure rates over all follow-up of group C and A after adjustment for sex (adjusted OR = 3.09; 95%CI = 1.32-7.20; P-value = .009), but no significant difference was found between group B and A or C and B in the primary and/or secondary efficacy endpoints. Side effects from the treatment were found in 12% (7/60); 2 in group A, 4 in group B, and 1 in group C. Four of these were likely due to LiCO3 side effects.

CONCLUSIONS

Treatment of rapid turnover Graves' disease patients with high dose I-131 (7.4 MBq/g) provides significantly higher cure rates at 12 months, and 3 times odds of cure than 3.7 MBq/g I-131 plus LiCO3 with lesser side effects. We thus recommend 7.4 MBq I-131/g for treatment in these patients.

Impact of injection time on migration of SPECT seizure onset in temporal lobe epilepsy

In this work, we investigated an impact of injection time on migration of seizure-onset in ictal/interictal single photon emission computed tomography (SPECT) study for patients with temporal lobe epilepsy. We selected 33 patients with refractory temporal lobe epilepsy who underwent ictal/interictal SPECT studies and had preoperative intracranial EEG result or surgical resection which was used as reference for seizure location. We divided all patients into two groups, which are the fast and the delayed groups; the delayed group comprised patients with injection time more than a cutoff time and vice versa. Using the subtraction ictal-interictal SPECT co-registered with SPECT (SISCOS) with varied Z-threshold (1.0, 1.5, 2.0 and 2.5), a method similar to subtraction ictal SPECT co-registered to magnetic resonance imaging (MRI) (SISCOM), a seizure-onset region in the SISCOS image was localized at the region with maximum sum of Z-scores. For each pair of cutoff time and Z-threshold, we determined the migratory proportion which was defined as the proportion of patients whose seizure-onset location based on SISCOS image was discordant with the reference. At cutoff time of 32-35 seconds and the Z-threshold of 2.0, the migratory proportion values were 7/26 (26.9%) and 5/7 (71.4%) in the fast and the delayed groups, respectively. At the same range of cutoff time with the Z-threshold of 2.5, the migratory proportion was 8/26 (30.8%) in the fast group while the proportion was 5/7 (71.4%) in the delayed group. Using Fisher's exact test, the migratory proportion values at the Z-threshold of 2.0 and 2.5 were significantly different between the fast and the delayed groups (p = 0.0709 and 0.0838, respectively), suggesting that patients with temporal lobe epilepsy who undergo an ictal/interictal SPECT study with injection time longer than 35 seconds tend to have seizure-onset zone migration in the SISCOS analysis with the traditionally-used Z-threshold of 2.0.

Joint reconstruction of Ictal/inter-ictal SPECT data for improved epileptic foci localization

PURPOSE

To improve the performance for localizing epileptic foci, we have developed a joint ictal/inter-ictal SPECT reconstruction method in which ictal and inter-ictal SPECT projections are simultaneously reconstructed to obtain the differential image.

METHODS

We have developed a SPECT reconstruction method that jointly reconstructs ictal and inter-ictal SPECT projection data. We performed both phantom and patient studies to evaluate the performance of our joint method for epileptic foci localization as compared with the conventional subtraction method in which the differential image is obtained by subtracting the inter-ictal image from the co-registered ictal image. Two low-noise SPECT projection datasets were acquired using ^99m Tc and a Hoffman head phantom at two different positions and orientations. At one of the two phantom locations, a low-noise dataset was also acquired using a ^99m Tc-filled 3.3-cm sphere with a cold attenuation background identical to the Hoffman phantom. These three datasets were combined and scaled to mimic low-noise clinical ictal (three different lesion-to-background contrast levels: 1.25, 1.55, and 1.70) and inter-ictal scans. For each low-noise dataset, 25 noise realizations were generated by adding Poisson noise to the projections. The mean and standard deviation (SD) of lesion contrast in the differential images were computed using both the conventional subtraction and our joint methods. We also applied both methods to the 35 epileptic patient datasets. Each differential image was presented to two nuclear medicine physicians to localize a lesion and specify a confidence level. The readers' data were analyzed to obtain the localized-response receiver operating characteristic (LROC) curves for both the subtraction and joint methods.

RESULTS

For the phantom study, the difference between the mean lesion contrast in the differential images obtained using the conventional subtraction versus our joint method decreases as the iteration number increases. Compared with the conventional subtraction approach, the SD reduction of lesion contrast at the 10^th iteration using our joint method ranges from 54.7% to 68.2% (P < 0.0005), and 33.8% to 47.9% (P < 0.05) for 2 and 4 million total inter-ictal counts, respectively. In the patient study, our joint method increases the area under LROC from 0.24 to 0.34 and from 0.15 to 0.20 for the first and second reader, respectively. We have demonstrated improved performance of our method as compared to the standard subtraction method currently used in clinical practice.

CONCLUSION

The proposed joint ictal/inter-ictal reconstruction method yields better performance for epileptic foci localization than the conventional subtraction method.

Cardio-metabolic risk factors in youth with classical 21-hydroxylase deficiency

Patients with congenital adrenal hyperplasia (CAH) appear to have adverse cardiovascular risk profile and other long-term health problems in adult life, but there are limited data in young CAH patients. We aim to evaluate the cardio-metabolic risk factors in adolescents and young adults with classical 21-hydroxylase deficiency (21-OHD). We performed a cross-sectional study of 21 patients (17 females) with classic CAH detected clinically and not through newborn screening, aged 15.2 ± 5.8 years, and 21 healthy matched controls. Anthropometric, biochemical, inflammatory markers, and body composition using dual-energy X-ray absorptiometry were measured. Obesity was observed in 33% of the CAH patients. The waist/hip ratio and waist/height ratio were significantly higher in CAH patients. Five out of 21 patients (24%) had elevated blood pressure. Silent diabetes was diagnosed in one patient (4.8%), but none in the control group. Serum leptin and interleukin-6 levels were not different between groups, but hs-CRP levels tended to be higher in CAH patients. Other metabolic profiles and body composition were similar in CAH and controls.

CONCLUSION

Adolescents and young adults with CAH appear to have an increased risk of obesity and cardio-metabolic risk factors. Close monitoring, early identification, and secondary prevention should be implemented during pediatric care to improve the long-term health outcomes in CAH patients. What is Known: • Lifelong glucocorticoid (GC) replacement is the main treatment modality in patients with congenital adrenal hyperplasia which predispose to an adverse metabolic profile. • Adult CAH patients have adverse cardiovascular risk profile and other long-term health problems. What is New: • Adolescents and young adults with CAH appear to have an increased risk of obesity and cardio-metabolic risk factors.

Partial-volume effect correction in positron emission tomography brain scan image using super-resolution image reconstruction

OBJECTIVE

The partial-volume effect (PVE) is a consequence of limited (i.e. finite) spatial resolution. PVE can lead to quantitative underestimation of activity concentrations in reconstructed images, which may result in misinterpretation of positron emission tomography (PET) scan images, especially in the brain. The PVE becomes significant when the dimensions of a source region are less than two to three times the full width at half maximum spatial resolution of the imaging system. In the present study, the ability of super-resolution (SR) image reconstruction to compensate for PVE in PET was characterized.

METHODS

The ability of SR image reconstruction technique to recover activity concentrations in small structures was evaluated by comparing images before and after image reconstruction in the NEMA/IEC phantom (Washington, DC), in the Hoffman brain phantom and in four human brain subjects (three normal subjects and one atrophic brain subject) in terms of apparent recovery coefficient (ARC) and percentage yield.

RESULTS

Both the ARC and percentage yield are improved after SR implementation in NEMA/IEC phantom and Hoffman brain phantom. When tested in normal subjects, SR implementation can improve the intensity and justify SR efficiency to correct PVE.

CONCLUSION

SR algorithm can be used to effectively correct PVE in PET images.

ADVANCES IN KNOWLEDGE

The current research focused on brain PET scanning exclusively; future work will extend to whole-body imaging.

Comparison of brain perfusion SPECT parameters accuracy for seizure localization in extratemporal lobe epilepsy with discordant pre-surgical data

OBJECTIVE

Extratemporal lobe epilepsy is difficult to localize. We aimed to define the best parameter(s) of SPECT for confirmation of seizure origin among the region of maximum cerebral perfusion in ictal phase (MP), maximum change of cerebral perfusion from interictal to ictal phase (MC), and maximum extent of hyperperfusion in ictal phase (ME) of (99m)Tc ECD brain perfusion SPECT as well as combined SPECT parameters, and combined SPECT and MRI for seizure localization in extratemporal lobe epilepsy.

MATERIALS AND METHODS

Twenty intractable extratemporal lobe epilepsy patients who had (99m)Tc-ECD brain SPECT were reviewed. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of single SPECT parameter, combined SPECT parameters, and combined SPECT and MRI parameters for localization of seizure origin were calculated using pathology and surgical outcomes (Engel class I and II) as gold standards.

RESULTS

Combined SPECT parameters provided more specificity, PPV and accuracy than single SPECT parameters. The best combined SPECT parameters was MP+MC with 80.6 % accuracy, 92.4 % specificity and 43.8 % PPV. Combination of SPECT parameter with MRI (ME+MRI) was the most sensitive (41.7 %), specific (97.5 %), accurate (88.2 %) parameter and had highest PPV (76.9 %) and NPV (89.3 %) for seizure localization. It improved specificity and PPV when compared to MRI alone.

CONCLUSION

Combined SPECT parameters improved the specificity and accuracy in seizure localization. The most specific and accurate SPECT combination is MP+MC. The combined SPECT parameter with MRI further improved sensitivity, specificity, accuracy, PPV and NPV. The authors recommend using SPECT combination, MP+MC, when MRI is negative and ME+MRI when there is MRI lesion.

Factors affecting bilateral temporal lobe hypometabolism on 18F-FDG PET brain scan in unilateral medial temporal lobe epilepsy

Bilateral temporal lobe hypometabolism (BTH) on (18)F-FDG PET brain scan is frequently seen in unilateral medial temporal lobe epilepsy (mTLE). This study aimed to identify the factors that influence BTH in patients with mTLE in order to minimize the significant factor(s) prior to performing a FDG-PET brain scan. Forty patients with unilateral mTLE who underwent (18)F-FDG PET scan for presurgical epilepsy workup were included. Bilateral temporal lobe hypometabolism of the anterior and medial parts of the temporal lobe was identified by a semiquantitative visual scale. Lateralization of TLE was identified by either intracranial EEG (22/40 cases) and/or improvement of seizure 2 years after temporal lobectomy (37/40 cases). The factors analyzed included basic demographic characteristics (age, sex, occupation, years of education, and handedness), history related to seizure (age at epilepsy onset and epilepsy duration, history of febrile seizure and head injury, frequency of seizure with impaired cognition in the last 3 months, presence of secondarily generalized tonic-clonic seizure, automatism side, presence of postictal confusion, and side of MRI temporal abnormality), information during video-EEG monitoring (clinical lateralization, interictal scalp EEG lateralization (interictal epileptiform discharge), and ictal scalp EEG lateralization), and information during the FDG-PET study (duration from the last seizure (≤2 days or >2 days), last seizure type, and the presence of slow waves or sharp waves during the FDG uptake period). Significant factors related to BTH were analyzed using multivariate analysis. Only the ≤2-day duration from the last seizure to the PET scan shows a significant effect (p=0.021) on BTH finding with 15 times greater incidence compared to a duration >2 days. Bilateral temporal lobe hypometabolism, which causes conflict in lateralizing the epileptogenic zone in temporal lobe epilepsy, can be avoided by performing PET scan more than 2 days after the last seizure.

Outcomes after temporal lobectomy for temporal lobe epilepsy with hippocampal sclerosis

OBJECTIVE

Outcome predictors from the pure cohorts of patients with temporal lobe epilepsy (TLE) with hippocampal sclerosis (HS) are limited The aim of the present study was to assess seizure outcomes and predictive factors in groups of well-defined patients with TLE-HS.

MATERIAL AND METHOD

One hundred forty eight patients with drug resistant TLE who had magnetic resonance imaging (MRI) that demonstrated unilateral HS underwent temporal lobectomy between 2004 and 2008 by a single neurosurgeon. All patients had completed at least two years of follow-up. Seizure outcome was categorized into seizure-free and not seizure-free.

RESULTS

Ninety-five patients (64.2%) were seizure-free after surgery at two years of follow-up. At four years follow-up, 47 patients (77.1%) were seizure-free for at least two years. There was no operative mortality or significant morbidity. No clinical variables are predictive of surgical outcomes at two and four years offollow-up.

CONCLUSION

Temporal lobectomy for drug-resistant TLE with HS is safe and effective. The authors did not identify predictive factors of surgical outcomes in TLE-HS.

Value of Osteoporosis Self-assessment Tools for Asians (OSTA) with or without Brown's clinical risk factors in detection of postmenopausal osteoporosis

OBJECTIVE

To evaluate the value of Osteoporosis Self-assessment Tools for Asians (OSTA) score, Brown's clinical risk assessment and their combination as screening tools for postmenopausal osteoporosis.

METHODS

Two hundred postmenopausal women were enrolled between August 2010 and January 2011. The weight and age of all participants were collected for the OSTA score. Clinical risk factors were collected for Brown's criteria. Bone mineral density was measured using dual-energy X-ray absorptiometry.

RESULTS

The mean age (± standard deviation (range)) of the studied population was 60.1 ± 7.8 (41-81) years. Twenty-one percent of the participants had either osteoporosis of the lumbar spine, or femoral neck or both, of which 8% had osteoporosis at the lumbar spine and 17% had osteoporosis at the femoral neck. The sensitivity and specificity for OSTA score cut-off values of ≤ -1 were 78.6% and 58.2% and for Brown's clinical risk factors were 57.1% and 71.5%, respectively. When the OSTA score of ≤ -1 and Brown's clinical risk factors were combined to screen participants with positive values for one or both test(s), the sensitivity increased from 78.6% to 81.0%, while the specificity decreased from 58.2% to 50.6%. The positive predictive values of the OSTA score, Brown's clinical criteria and the combined tools ranged between 30.4 and 70.6%.

CONCLUSIONS

An OSTA score of ≤ -1 seems to have higher sensitivity compared to Brown's clinical risk factor assessment. The combination of both tools provides a slight improvement in sensitivity but with a decline in specificity.

Prevention of bone loss in children receiving long-term glucocorticoids with calcium and alfacalcidol or menatetrenone

BACKGROUND

Long-term treatment with glucocorticoids can induce bone loss and increase fracture risks.

AIM

To compare the efficacy of a 12-month treatment between alfacalcidol and menatetrenone in preventing bone loss in children treated with long-term glucocorticoids.

PATIENTS AND METHODS

Twenty children on a stable dosage of glucocorticoids were randomly divided into two groups (alfacalcidol or menatetrenone). Each group received the assigned treatment along with 400 mg of elemental calcium daily for 12 months. Patients receiving medications affecting bone metabolism or patients with impaired kidney function were excluded. Bone density parameters, including lumbar spine bone mineral content (BMC), bone mineral density (BMD), and BMD Z-score were assessed by dual-energy X-ray absorptiometry at baseline and at 12-month follow-up. Bone mineral apparent density (BMAD) was calculated as a size-adjusted measurement of BMD in growing children. Baseline characteristics and bone density parameters were similar between both groups.

RESULTS

After 12 months, BMC and BMD were significantly increased from baseline in both groups, but did not differ between the groups. The BMD Z-score at 12-month follow-up was significantly decreased from baseline in the menatetrenone group. BMAD was significantly increased from baseline in the alfacalcidol group.

CONCLUSIONS

Administration of long-term glucocorticoids in children justifies an intervention to preserve bone mass. Calcium supplementation along with alfacalcidol can prevent further bone loss to a greater extent than menatetrenone in this group of patients.

Utility of 8F-FDG PET/CT in well differentiated thyroid carcinoma with high serum antithyroglobulin antibody

OBJECTIVE

Evaluate the utility of 18F-FDG PET/CT in the follow-up of differentiated thyroid cancer (DTC) patients with high serum antithyroglobulin antibody (TgAb) but negative serum thyroglobulin (Tg) measurements and negative 131I whole-body scans (WBS).

MATERIAL AND METHOD

The present study included 22 consecutive patients with high serum TgAb levels. They had negative serum Tg measurements and negative 131I WBS. PET/CT was performed 60 min after intravenous injection of 227.55-455.47 MBq (6.15-12.31 mCi) of 18F-FDG using a combined PET/CT scanner. Co-registered CT images were used to differentiate physiologic from pathologic tracer uptake. Findings on 18F-FDG PET/CT were correlated with tissue pathology follow-up imaging or clinical follow-up served as a reference.

RESULTS

Twenty-two well differentiated thyroid cancerpatients participated. Twelve had positive findings on 18F-FDG PET/CT six were true positives and six were false-positives. 18F-FDG PET/CT results were true negative in 10 patients and the authors found no false-negative patients in the present study. The overall sensitivity, specificity and accuracy of 18F-FDG PET/CT were 100%, 62.5% and 72.7%, respectively. TgAb levels, which are appropriated for sending DTC patient who are 131I WBS negative but have elevated serum TgAb levels to undergo 18F-FDG PET/CT scan, should be more than or equal to 414.6 IU/ml. Results should be highly consider positive if max SUV value is equal or greater than 4.5.

CONCLUSION

18F-FDG PET/CT is a useful tool for localizing recurrent or metastatic DTC patients, who have negative 131I WBS but elevated serum TgAb levels. The authors recommend its use in clinical management of selected cases regardless of the TgAb level being more than or equal to 415 IU/ml.

Rosiglitazone effect on radioiodine uptake in thyroid carcinoma patients with high thyroglobulin but negative total body scan: a correlation with the expression of peroxisome proliferator-activated receptor-gamma

BACKGROUND

Thyroid carcinoma patients with high thyroglobulin (Tg) level but negative total body scan (TBS) are difficult to treat with radioiodine (RAI). The objective of this study was to determine if treatment with rosiglitazone (RZ), a peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist, was associated with an increase in RAI uptake in thyroid carcinoma patients with high serum Tg and negative TBSs. We also determined if there was a correspondence between the effect of RZ and the degree of staining for PPAR-gamma within thyroid cancer tissues.

METHODS

We prescribed 8 mg of RZ daily for 6 weeks in 23 patients with epithelial cell thyroid carcinoma who previously had negative posttherapeutic I-131 total body scans (post Rx TBSs) with high serum Tg concentrations. Diagnostic total body scans (Dx TBSs) before and 6 weeks after RZ treatment were compared. An ablative dose of I-131 was then given to all patients, and post Rx TBS was performed to evaluate RAI uptake. Immunohistochemical staining of PPAR-gamma expression in thyroid cancer biopsies was done to correlate this with possible effects of RZ on RAI uptake.

RESULTS

Seven patients had strong PPAR-gamma-positive staining in thyroid biopsies, nine patients had weakly positive staining, and seven patients had negative staining. Five of seven patients with strong staining had either positive post Rx TBS, or both Dx TBS and post Rx TBS. One of nine patients with weak staining had positive Dx TBS and post Rx TBS. In contrast, none of the seven patients with negative staining had positive TBS.

CONCLUSIONS

RZ can increase RAI uptake in thyroid tissue in the majority of patients with epithelial cell thyroid carcinoma whose previous posttherapeutic I-131 scans were negative provided they have high intensity and extent of PPAR-gamma expression in thyroid tissue. Few, if any, patients with weak or no PPAR-gamma expression in thyroid cancer tissue increase RAI uptake after RZ treatment.

Quantitative study of new bone formation in distraction osteogenesis of craniofacial bones by bone scintigraphy

Although distraction osteogenesis is widely accepted as a technique to augment the craniofacial skeleton, timing to start distraction after an osteotomy or to remove distractors is basically based on studies on long bones. Because bone scintigraphy is well known to be the gold standard for quantitative measurement of bone formation, we conducted this pilot study to evaluate its feasibility as a tool for assessing new bone formation by distraction osteogenesis. Five patients with midface hypoplasia and four with mandibular hypoplasia were studied. Each patient had five bone scans: before surgery, 3 and 30 days after stopping distraction, and 3 days before and 3 months after distractor removal. Radiotracer uptake values at distraction sites were measured at 1 and 3 hours. Each uptake value was compared with preoperative study as uptake ratio. A typical pattern of radiotracer uptake ratio was observed in all cases with successful distraction. Uptake rose to the maximum during the consolidation period and remained at or above the preoperative level until the study end point. In one patient who had mandibular distraction and nonunion of the right ramus, there was no uptake peak during early consolidation as seen in the successfully distracted body and in the other cases. Bone scintigraphy was found to be a useful investigation in craniofacial distraction. It showed the dynamic of new bone formation by demonstrating the osteoblastic activity, which is important objective information for determining distraction rate and consolidation duration in each case. It may also be a tool that can predict the outcome of distraction osteogenesis.

Comparative analysis of MR imaging, Ictal SPECT and EEG in temporal lobe epilepsy: a prospective IAEA multi-center study

BACKGROUND AND PURPOSE

MR imaging, ictal single-photon emission CT (SPECT) and ictal EEG play important roles in the presurgical localization of epileptic foci. This multi-center study was established to investigate whether the complementary role of perfusion SPECT, MRI and EEG for presurgical localization of temporal lobe epilepsy could be confirmed in a prospective setting involving centers from India, Thailand, Italy and Argentina.

METHODS

We studied 74 patients who underwent interictal and ictal EEG, interictal and ictal SPECT and MRI before surgery of the temporal lobe. In all but three patients, histology was reported. The clinical outcome was assessed using Engel's classification. Sensitivity values of all imaging modalities were calculated, and the add-on value of SPECT was assessed.

RESULTS

Outcome (Engel's classification) in 74 patients was class I, 89%; class II, 7%; class III, 3%; and IV, 1%. Regarding the localization of seizure origin, sensitivity was 84% for ictal SPECT, 70% for ictal EEG, 86% for MRI, 55% for interictal SPECT and 40% for interictal EEG. Add-on value of ictal SPECT was shown by its ability to correctly localize 17/22 (77%) of the seizure foci missed by ictal EEG and 8/10 (80%) of the seizure foci not detected by MRI.

CONCLUSIONS

This prospective multi-center trial, involving centers from different parts of the world, confirms that ictal perfusion SPECT is an effective diagnostic modality for correctly identifying seizure origin in temporal lobe epilepsy, providing complementary information to ictal EEG and MRI.

Successful resection of Hypothalamic Hamartoma with intractable gelastic seizures--by transcallosal subchoroidal approach

A 19-year old female with intractable gelastic seizures was found to have 0.7 x 1.8 x 1.8 cm elliptical mass on the floor of the third ventricle. The signal intensity on the Magnetic Resonance Imaging (MRI) was consistent with the Hypothalamic Hamartoma (HH). Ictal EEG demonstrated rhythmic 7 Hz waves over Fp2, F4, and C4 with spreading to the right temporal region and then bilaterally. Ictal Single Photon Emission Computerized Tomography (SPECT) showed hyperperfusion at hypothalamic and medial frontopolar regions. The patient underwent surgical resection using Trans Callosal Subchoroidal Approach (TCSA) to the third ventricle. Pathological finding confirmed the diagnosis of hypothalamic hamartoma. Following the operation, she has been seizure free up to 12 months. Thereafter, provoked seizures seldom occurred and there has been improvement in her memory, emotional control and independence. This appears to be the first report of this surgical approach for HH, which is less likely to disturb memory function compared to previously described interfoniceal approach.

The first invasive EEG monitoring for surgical treatment of epilepsy in Thailand

The authors report the first invasive electroencephalography (EEG) monitoring in Thailand in a patient who had intractable left temporal lobe epilepsy. The seizure origin and functioning cortices were identified The corresponding epileptogenic zone was resected without functional deficit. The patient has become seizure free 1 year since surgery. Subdural EEG monitoring with cortical stimulation have been developed at this tertiary epilepsy center The technique provides essential evidence for the surgical decision so that the best post operative outcome can be achieved.

The difference among stress and rest normal reference databases using non-corrected, scatter corrected, and scatter with attenuation corrected Bull's eye myocardial perfusion scintigraphy in both genders

OBJECTIVES

To compare 3 types of Bull's eye normal reference maps; non-corrected, scatter corrected, and scatter with attenuation corrected Bull's eye in both genders.

MATERIAL AND METHOD

Sixty-seven normal healthy males and females volunteered for the present study. After screening tests to identify low post-test (exercise EKG) likelihood of coronary artery disease, 41 subjects (20 males and 21 females) had stress and rest myocardial perfusion scintigraphy (99mTc-sestamibi). The data were reconstructed by filtered back projection reconstruction in three ways as follows; (1) non-correction (NoC), (2) scatter elimination only (SC), (3) scatter elimination and attenuation correction (SC+AC). Three sets of reconstructed data of both stress and resting studies were added into 6 sets of Bull's eye. The data of each Bull's eve were normalized to 100% of the maximum count. Percentage of uptake in each area was compared by t-test statistics.

RESULTS

Stress and rest count distribution of NoC and SC sets were lowest at the inferior wall, followed by the septal wall, anterior wall, and lateral wall in both genders. In the SC+AC sets; septum and lateral walls showed more uptake than anterior and inferior walls. A significant difference of percentage uptake between stress and rest images at septum in NoC and SC images in male and in SC image in female was observed. No difference was seen in the SC+AC groups.

CONCLUSION

There was similarity of count distribution between NoC and SC images. SC+AC caused more uniform image. However; some non-uniformity was observed. The use of sex-independent SC+AC bull's eye is possible. Stress study can be omitted for bull's eye collection of normal files.

Quality of life after successful epilepsy surgery: evaluation by occupational achievement and income acquisition

OBJECTIVES

A comprehensive epilepsy surgery program has been developed at Chulalongkorn University Hospital, Thailand to reach an international standard level, rendering patients good surgical outcomes comparable to developed countries. After successful operation, seizure free patients have become independent, self earning or employed. However, quality of life (QOL) in terms of occupational achievement and income acquisition after epilepsy surgery has never been studied. These indicators reflect the ultimate QOL in the aspects of actual independency, intact brain functions, mental health and psycho-social interactions. The authors therefore conduct the study on improvement of QOL after successful epilepsy surgery using these parameters.

MATERIAL AND METHOD

One hundred and eleven intractable epilepsy who have become seizure free to worthwhile improved (Engel class I to III) after standard presurgical evaluation and epilepsy surgery from January 2002 to December 2004 were evaluated. The patients were followed up for 3 years. The occupational status and incomes were categorized according to the ranking of the patients' functioning levels. The pre and post surgery work abilities, employment and incomes were interviewed and compared. Mc Nemar test and paired t-test were used for statistical analyses.

RESULTS

The average age of the 111 adults (54 males and 57 females) was 33.7 +/- 9.2 years. Eighty two percent of the patients had temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) and underwent standard anterior temporal lobectomy. The rest had tumors, cortical dysplasia or scar and received lesionectomy or cortical resection assisted by intra-operative or intra-cranial EEG. The overall seizure free rate is 83.8%. The occupational status of the subjects was shown to improve significantly after surgery from unemployed to higher categories of professional achievement (p < 0.001). The number of unemployed and no income individuals decreased from 66 to 25 cases (62.1% reduction rate) after surgery (p < 0. 001). Reciprocally, the number of persons who achieved professional jobs with regular incomes or salaries increase from 30 to 53 cases (43.4% increasing rate) (p < 0.001). The patients who have not acquired any income increment showed improvement in working ability after epilepsy surgery. The average annual incomes per capita shows the increasing rate of 45.08%, from 55,657.85 Baht (approximately U.S. dollars 1390) to 80,748.15 Baht (approximately U.S. dollars 2018), with strong statistical significance (p < 0.001). The improvement is best seen in seizure free than in non-seizure free subjects.

CONCLUSION

The present study, to the authors 'knowledge, is the first to use work abilities, professional achievement and income acquisition to assess the ultimate QOL after epilepsy surgery. Most subjects have been shown to significantly improve their postoperative lives in terms of occupational accomplishment and income increment, especially in seizure free individuals. The need for expansion of epilepsy surgery is emphasized.

The effect of phenobarbital on the accuracy of technetium-99m diisopropyl iminodiacetic acid hepatobiliary scintigraphy in differentiating biliary atresia from neonatal hepatitis syndrome

Biliary atresia (BA) and neonatal hepatitis syndrome (NHS) are major causes of cholestatic jaundice in infancy. Technetium-99m diisopropyl iminodiacetic acid hepatobiliary scintigraphy (99mTc-DISIDA scan) is widely used in the differentiation of these two entities. The objective of this study was to evaluate the effect of phenobarbital premedication on the accuracy of 99mTc-DISIDA scan. Ninety-five cholestatic infants (38 females and 57 males) with an age range of 2 weeks to 4 months (mean 2.1 mo) who underwent 99mTc-DISIDA scan testing were retrospectively reviewed. The patients were divided into 3 groups according to the history of phenobarbital administration prior to 99mTc-DISIDA scan examination. Group 1 (n = 48), group 2 (n = 29), and group 3 (n = 18) received phenobarbital at the dosage of 5 mg/kg/day for at least 5 days, less than 5 mg/kg/day or less than 5 days, and no premedication, respectively. The accuracy of 99mTc-DISIDA scan in differentiating BA from NHS in group 1, 2, and 3 was 72.92 per cent, 89.66 per cent, and 100 per cent, respectively. No significant difference was seen between the patients who received and did not receive phenobarbital in terms of age at presentation, age at onset of jaundice, and liver function tests. In conclusion, phenobarbital therapy may not be necessary prior to 99mTc-DISIDA scan examination in the evaluation of cholestatic infants and thus a delay in diagnosis and surgical therapy of BA can be avoided.

Detection of acute cerebral ischaemia with Tc-99m apcitide scintigraphy

The established indication for Tc99m apcitide scintigraphy is for detecting deep venous thrombosis. However, due to its mechanism of binding to GP IIb/IIIa receptors on activated platelets, it can be used to image acute cerebral thrombosis. I report a patient with an acute ischaemic stroke, with right leg swelling, referred for Tc99m apcitide scintigraphy to show of deep venous thrombosis. There was no abnormal uptake in the legs but there was in the left parieto-occipital region. This correlated with the clinical and CT data, indicating an acute ischaemic stroke in this area.

Enhancement of radioiodine uptake in hyperthyroidism with hydrochlorothiazide: a prospective randomised control study

The aim of this study was to determine whether hydrochlorothiazide (HCTZ) could improve radioiodine uptake in low-uptake hyperthyroid patients. Eighteen hyperthyroid patients with low 3-h and 24-h iodine-131 uptake were recruited to the study. Eleven patients were assigned to the HCTZ group, and seven to the control group. Two weeks after the first, baseline uptake study, a second uptake study was performed. Patients in both groups had a low-iodine diet after the first uptake study. In the HCTZ group, 50 mg of HCTZ was administered twice a day for 5 days prior to the second uptake study. Improvement in uptake at 3 and 24 h in the second uptake study, as compared with the baseline study, was assessed within and between groups. In the control group, compared with the baseline study there was a significant improvement in uptake at 3 h ( P=0.03) but a non-significant improvement at 24 h ( P=0.07). In the HCTZ group, significant improvements were observed at both 3 h ( P=0.0005) and 24 h ( P=2.28 x 10(-5)). Patients in the HCTZ group had statistically greater improvement in uptake at both 3 h and 24 h compared with the control group ( P=0.003 and 0.0008, respectively). There was a 7.18-fold average improvement in uptake in the HCTZ group at 24 h, compared with only a 1.33-fold improvement in the control group. Administration of HCTZ significantly improves 24-h radioiodine uptake in high-iodide pool, low-uptake hyperthyroid patients compared with patients who have received a low-iodine diet alone.

Relationship between vesicoureteral reflux and renal cortical scar development in Thai children: the significance of renal cortical scintigraphy and direct radionuclide cystography

Relationship of vesicoureteral reflux (VUR), urinary tract infection (UTI) and subsequent renal scarring nowadays is still in question. This study aimed to determine 1) the incidence of cortical scarring in Thai children presenting with upper urinary tract infection, 2) the association between VUR with acute pyelonephritis and subsequent renal scarring, 3) the use of DMSA and direct radionuclide cystography (DRNC) scintigraphy in children with UTI. Sixty newly diagnosed UTI children underwent DRNC and Tc-99m DMSA renal cortical scintigraphy at the time of first UTI diagnosis and 6 months later. There were no significant differences of age, sex, type of antiobiotics and pathogens (E. coli vs non-E. coli) between those who did and did not develop scars (p>0.05). 58/98 of 1st DMSA abnormal kidneys (59.18%) developed scars. 60.20 per cent of 98 positive 1st DMSA had VUR while 80.33 per cent of 61 with VUR had positive 1st DMSA. 59.02 per cent of these 61 kidneys developed scars. Scar occurrence were 18.7 times in high grade VUR compared to low grades. In conclusion, there was a high incidence of acute pyelonephritis in the presence of VUR but acute pyelonephritis does not necessarily need VUR for its development. High grade reflux with upper UTI, is a strong indicator for renal scarring. Children presenting with UTI, irrespective of age, sex, or pathogen, should have both DMSA and DRNC scintigraphy performed to identify upper UTI and high risk patients who will develop subsequent renal scarring.

Detection of restenosis after percutaneous transluminal coronary angioplasty using the exercise treadmill test and technetium 99m-sestamibi scintigraphy

BACKGROUND

The detection of myocardial ischemia after percutaneous transluminal coronary angioplasty (PTCA) is important because 30-50 per cent of the patients will develop restenosis within 6 months. Symptoms of chest pain and exercise stress test (EST) have shown to be less sensitive for detection of ischemia than exercise Technetium-99m Sestamibi (Tc-99m MIBI). The purpose of this study was to compare the sensitivity and specificity of chest pain, EST and Tc-99m MIBI with coronary angiography (CAG).

METHOD

Tc-99m MIBI with SPECT imaging was performed at months 1, 3 and 6 and CAG was repeated 6 months after successful PTCA. Earlier Tc-99m MIBI and CAG were performed in patients with recurrent angina pectoris or suspected restenosis.

RESULTS

Forty six patients (M 29, F 17) who had undergone successful angioplasty were prospectively enrolled. Their mean age was 61 +/- 19 yrs. Eighty eight lesions (LAD63%, LCX34%, RCA19%) were performed. Lesion characteristics were type A in 9 per cent, type in B 30 per cent and type C in 61 per cent. Fifty four per cent of PTCA were performed for single vessel disease and 46 per cent for multivessel disease. The mean duration of time between PTCA and follow-up CAG was 6.1 +/- 2.7 months. We detected restenosis from CAG in 58 per cent of the cases. The Tc-99m MIBI had higher sensitivity to detect restenosis than anginal pain (85.0% vs 39.4% p < 0.005) or EST (85.0% vs 63.6% p < 0.05) when compared with CAG. The overall accuracy of Tc-99m MIBI for the detection of restenosis was 80 per cent.

CONCLUSION

Tc-99m MIBI with SPECT imaging constitutes a better means than symptoms or exercise test to detect restenosis after successful coronary angioplasty.

131I MIBG therapy in neuroblastoma: mechanisms, rationale, and current status

131I MIBG has been used as palliative treatment of neuroblastoma patients with recurrent or persistent disease who failed other modalities of treatment. Since the results were promising, the concept arose of using it in conjunction with other modalities, either as an up-front treatment or as combination therapy. This article reviews the principle of 131I MIBG treatment, in conjunction with other modalities currently used for the treatment of neuroblastoma, in an attempt to improve the final outcome.