Thai National Guideline for Nuclear Medicine Investigations in Epilepsy.

Epilepsy is a disorder of the brain, which is characterized by recurrent epileptic seizures. These patients are generally treated with antiepileptic drugs. However, more than 30% of the patients become medically intractable and undergo a series of investigations to define candidates for epilepsy surgery. Nuclear Medicine studies using Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) radiopharmaceuticals are among the investigations used for this purpose. Since available guidelines for the investigation of surgical candidates are not up-to-date, The Nuclear Medicine Society of Thailand, The Neurological Society of Thailand, The Royal College of Neurological Surgeons of Thailand, and The Thai Medical Physicist Society has collaborated to develop this Thai national guideline for Nuclear Medicine study in epilepsy. The guideline focuses on the use of brain perfusion SPECT and F-18 fluorodeoxyglucose PET (FDG-PET), the mainly used methods in day-to-day practice. This guideline aims for effective use of Nuclear Medicine investigations by referring physicians e.g. epileptologists and neurologists, radiologists, nuclear medicine physicians, medical physicists, nuclear medicine technologists and technicians.

Simulated increased soft tissue thickness artefactually decreases trabecular bone score: a phantom study.

BACKGROUND: Trabecular bone score (TBS), which has been proposed to be used in complementary with bone mineral density (BMD) to improve the assessment of fracture risk, is negatively associated with body mass index (BMI). The effect of soft tissue, which is expected to be thicker in subjects with high BMI, on TBS was studied using three scan types: Hologic with fast array mode (Hfa), Hologic with high definition mode (Hhd), and GE-Lunar iDXA. METHODS: A spine phantom provided by Hologic for routine quality control procedure was scanned using three scan types: Hfa, Hhd, and iDXA. The phantom was scanned with an overlying soft tissue equivalent material (bolus used in radiotherapy) of 0 (without), 1, 2.5, 3.5, 5 and 7.5 cm thick. For each setting, 30 acquisitions were performed in the same way as for the quality control procedure. TBS was calculated using TBS iNsight® software version 2.1 on the same regions of interest as those used for lumbar spine BMD. RESULTS: Mean ± SD TBS of the phantom (without overlying soft tissue) were 1.379 ± 0.018, 1.430 ± 0.009, and 1.423 ± 0.005 using Hfa, Hhd, and iDXA, respectively. A one-way repeated measures ANOVA showed that there were statistically differences in TBS due to different thicknesses of soft tissue equivalent materials for all three scan types (p < 0.001). A Tukey post-hoc test revealed that the decrease in TBS was statistically significant (p < 0.001) when the soft tissue thickness was 1 cm (-0.0246 ± 0.0044, -0.0319 ± 0.0036, and -0.0552 ± 0.0015 for Hfa, Hhd, and iDXA, respectively). Although to a lesser degree, the effects were also statistically significant for BMD (p < 0.05): an increase for Hfa and Hhd but a decrease for iDXA. However, these changes did not exceed the least significant change (LSC) derived from patients. CONCLUSIONS: Increased soft tissue thickness results in lower TBS value. Although BMD is also affected, it is unlikely to pose a clinical problem because the change is unlikely to exceed the patient-derived LSC.

Age-Adjusted Dual X-ray Absorptiometry-Derived Trabecular Bone Score Curve for the Lumbar Spine in Thai Females and Males.

Trabecular bone score (TBS), which has been shown to discriminate patients with fractures from healthy individuals, decreases with age. This study was conducted to derive an age-adjusted normative TBS curve for each gender aged 30-80 + years to serve as reference data for Thai males and females. A cross-sectional study was conducted among employees from the Electricity Generating Authority of Thailand cohorts, after excluding those with conditions potentially affecting bone metabolism and analysis. The values of TBS at L1-L4 vertebrae were analyzed using a commercial software. Age-adjusted TBS curves were constructed using segmental linear regression analysis for each gender. Additional analysis was also performed on TBS with age, body mass index, and body mineral density (BMD) at L1-L4 vertebrae as covariates. A database of 848 healthy subjects (341 females and 507 males) aged 30-80+ years was created. The BMDs of both male and female subjects in the youngest decade were not statistically different from previous reports (p = 0.31 and 0.22 for females and males, respectively). In this age group, the mean TBS was higher in females, albeit not statistically significant (p = 0.12). Between the ages of 30-80+ years, female and male TBS dropped by 19.8% (0.40% per year) and 10.1% (0.20% per year), respectively. The association with TBS was weak for body mass index and moderate for BMD (coefficients of about -0.01 and 0.4-0.5, respectively). The age-adjusted reference curves for healthy Thai females and males aged 30-80+ years have been established.