Annals of Nuclear Medicine (v.27, #3)

The objective of this study was to identify specific brain lesions with regional perfusion abnormalities possibly associated with neuropsychological impairments (NPI), as sequela after mild traumatic brain injury (MTBI), using 99mTc-ethylcysteinate dimer single photon emission computed tomography (Tc-99m ECD SPECT) and its novel analytic software.We studied 23 patients with diffuse axonal injury with NPI group (Impaired-DAI), 26 with MTBI with NPI group (Impaired-MTBI) and 24 with MTBI without NPI group (Healthy-MTBI). In each subject, Tc-99m ECD SPECT images were analyzed by easy Z score imaging system (eZIS) and voxel-based stereotactic extraction estimation (vbSEE). Segmented into lobule levels, ROIs were set in 140 areas in whole brain, and relative regional low Tc-99m ECD uptake was computed as “extent” (rate of coordinates with Z score >2.0 in the ROI). Receiver operating characteristic analysis was performed using “extent” to discriminate the three groups.The highest area under the curve (AUC) value for data of Impaired-DAI and Healthy-MTBI groups was obtained in ROI on the left anterior cingulate gyrus (LtACG), with AUC of 0.93, optimal “extent” cutoff value of 10.9 %, sensitivity 87.0 %, specificity 83.3 %. The highest AUC value for data of Impaired-MTBI and Healthy-MTBI groups was also in the LtACG, with AUC of 0.87, optimal “extent” cutoff value of 9.2 %, sensitivity 73.1 %, specificity 83.3 %.Using two analytic software packages, eZIS and vbSEE, we identified specific lesions with low regional Tc-99m ECD uptake possibly associated with NPIs after MTBI. Especially, this trend was most marked in the left anterior cingulate gyrus in MTBI patients with NPIs and those with DAI. The optimal “extent” cutoff value, as a criterion for SPECT abnormality, might help the diagnosis of NPIs after MTBI.
Keywords: Mild traumatic brain injury; Neuropsychological impairments; Single photon emission computed tomography; Statistical imaging analysis

A hand-held beta imaging probe for FDG by Bipin Singh; Brendan C. Stack Jr.; Samta Thacker; Valeriy Gaysinskiy; Twyla Bartel; Val Lowe; Steven Cool; Gerald Entine; Vivek Nagarkar (203-208).
Advances in radiopharmaceuticals and clinical understanding have escalated the use of intraoperative gamma probes in surgery. However, most probes on the market are non-imaging gamma probes that suffer from the lack of ancillary information of the surveyed tissue area. We have developed a novel, hand-held digital Imaging Beta Probe™ (IBP™) to be used in surgery in conjunction with beta-emitting radiopharmaceuticals such as 18FDG, 131I and 32P for real-time imaging of a surveyed area with higher spatial resolution and sensitivity and greater convenience than existing instruments.We describe the design and validation of a hand-held beta probe intended to be used as a visual mapping device to locate and confirm excision of 18FDG-avid primary tumors and metastases in an animal model.We have demonstrated a device which can generate beta images from 18FDG avid lesions in an animal model.It is feasible to image beta irradiation in animal models of cancer given 18FDG. This technology may be applied to clinical mapping of tumors and/or their metastases in the operating room. Visual image depiction of malignancy may aid the surgeon in localization and excision of lesions of interest.
Keywords: 18FDG; PET; 131I; Imaging; Beta probe

Evaluation of Wegener’s granulomatosis using 18F-fluorodeoxyglucose positron emission tomography/computed tomography by Kimiteru Ito; Ryogo Minamimoto; Hiroyuki Yamashita; Setsuko Yoshida; Miyako Morooka; Momoko Okasaki; Akio Mimori; Kazuo Kubota (209-216).
Wegener’s granulomatosis (WG) is a relatively rare disease characterized by granulomatous necrotizing vasculitis that primarily involves small- and medium-sized vessels. Systemic findings observed on 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) have not been well reported. The purpose of this study was to evaluate the FDG PET/CT imaging in the diagnosis and follow-up of patients with WG.Thirteen FDG PET/CT images obtained for 8 patients (2 men and 6 women) with WG were retrospectively analyzed. Of these, 6 were performed for diagnosis, 2 for restaging and follow-up, and 5 for assessment of treatment efficacy. Maximum standardized uptake values (max SUVs) and visual analyses were used to interpret the FDG PET/CT images. In addition, nonenhanced CT findings obtained during FDG PET/CT were described.WG lesions of the upper respiratory tract and lung were more clearly detected by FDG PET/CT fusion imaging than by nonenhanced CT alone, and all of the active lesions showed decreased FDG uptake after treatment. In addition, FDG PET/CT can provide complementary information to indicate biopsy site based on FDG uptakes.FDG PET/CT is a feasible modality for evaluating lesion activities, therapeutic monitoring, and follow-up of WG. Furthermore, biopsy sites of WG lesions may be determined by FDG PET/CT.
Keywords: Wegener`s granuloma; Vasculitis; ANCA; PET/CT; FDG

A comparative study of FDG PET/CT and enhanced multi-detector CT for detecting liver metastasis according to the size and location by Jung Mi Park; Il Young Kim; Sang Won Kim; Sang Mi Lee; Hyun Gi Kim; Shin Young Kim; Hyung Chul Shin (217-224).
The aim of this study was to compare the diagnosability between 18F-fluorodeoxyglucose (FDG) PET/CT and enhanced multi-detector CT (MDCT) for the detection of liver metastasis (LM) according to the size and location in liver and to evaluate standard maximum standardized uptake values (SUVmax) of all liver metastatic lesions.One hundred two consecutive patients with malignancy who underwent both FDG PET/CT and MDCT for LM evaluation were retrospectively reviewed. Among them, 56 patients with LM were enrolled in this study. LM was confirmed by follow-up imaging studies after at least 6 months or by histopathology. FDG PET/CT and MDCT images were visually analyzed using three-point scale by the consensus of two radiologists and two nuclear medicine physicians. The size and location (central vs. sub-capsular) of the all liver lesions were evaluated using MDCT images. Furthermore, SUVmax of all liver lesions on FDG PET/CT images were calculated.A total of 146 liver lesions were detected by FDG PET/CT and MDCT and 142 of the lesions were diagnosed as LM. The detection rates of MDCT and FDG PET/CT for LM by visual analysis were 77 and 78 %, respectively. There was no significant difference of detection rate according to the overall location and size of the lesions. However, FDG PET/CT was more sensitive than MDCT for detecting small and sub-capsular LM. The detection rate of FDG PET/CT for LM was 68 % by the cutoff SUVmax of 2.7.Although the diagnosabilities of MDCT and FDG PET/CT for detecting LM were comparable, FDG PET/CT is superior to MDCT for detecting small LM located in the sub-capsular portion of liver.
Keywords: Metastasis; CT; PET/CT; Liver; Cancer

Standardization of image quality across multiple centers by optimization of acquisition and reconstruction parameters with interim FDG-PET/CT for evaluating diffuse large B cell lymphoma by Hiromitsu Daisaki; Ukihide Tateishi; Takashi Terauchi; Mitsuaki Tatsumi; Kazufumi Suzuki; Naoki Shimada; Hiroyuki Nishida; Akihiko Numata; Koji Kato; Koichi Akashi; Mine Harada (225-232).
A multicenter trial is currently underway using FDG-PET/CT to evaluate diffuse large B cell lymphoma in Japan (JSCT NHL10). Standardization of the image quality between the participating centers is a fundamental aspect of the study. Within the framework of JSCT NHL10, standardization of the image quality was attempted by optimizing the acquisition and reconstruction conditions using mid-therapy FDG-PET/CT for diffuse large B cell lymphoma. This report describes the procedures and results of this attempt.The acquisition protocols and imaging quality were initially determined at each center and again after modification. The image quality was based on performance with an 18F-filled National Electrical Manufacturers Association standards body phantom. We determined that the acquisition duration and reconstruction parameters of each scanner evaluated were in compliance with the Japanese guideline for the oncology FDG-PET/CT data acquisition protocol: synopsis of Version 1.0 (the Guideline) based on the results of the phantom experiments performed by the Core Laboratory.A total of 18 centers (19 scanners) participated in this trial. The center’s default protocol was unchanged for 9 scanners (47.4 %) and changed for 10 scanners (52.6 %). Both acquisition duration and reconstruction parameters were changed in 3 (15.8 %) of 10 scanners and the acquisition duration alone was changed in 7 (36.8 %) scanners. Also, the accuracy of the standardized uptake value (SUV) was evaluated with the acceptable level 1.0 ± 0.1, resulting in readjustment and recalibration in 2 scanners (10.5 %), which were confirmed to attain the acceptable accuracy after the required readjustment. As of August 2012, 21 patients have undergone an FDG-PET/CT examination under the acquisition protocols determined by the Core Laboratory. Evaluation of the image quality using several physical parameters confirmed that the accumulated data were of sufficient quality.Optimization of the acquisition protocol, in compliance with the guideline, was successfully achieved by the Core Laboratory in the framework of JSCT NHL10 to accumulate equivalent quality data across multiple centers. The progress of the trial was greatly facilitated by support from the Japan Society of Nuclear Medicine Working Group for Investigation of Response Evaluation Criteria in Malignant Tumors Using Standardized PET/CT (Principal Investigator: Ukihide Tateishi, MD., PhD).
Keywords: FDG; PET/CT; Diffuse large B cell lymphoma; Standardization; Multicenter study

Sensitive immunodetection of radiotoxicity after iodine-131 therapy for thyroid cancer using γ-H2AX foci of DNA damage in lymphocytes by Mariko Doai; Naoto Watanabe; Tomoko Takahashi; Mitsuru Taniguchi; Hisao Tonami; Kuniyoshi Iwabuchi; Daiki Kayano; Makoto Fukuoka; Seigo Kinuya (233-238).
The purpose of our study was to evaluate the degree of radiotoxicity to lymphocytes in thyroid cancer after iodine-131(I-131) therapy using γ-H2AX foci immunodetection.This study focused on 15 patients who underwent I-131 therapy for differentiated thyroid cancer after surgery. All patients received 3.7 GBq of I-131. Venous blood samples were collected from each patient before therapy and 4 days thereafter. Lymphocytes were isolated from the blood samples and subjected to γ-H2AX immunofluorescence staining.The number (mean ± SD) of foci per lymphocyte nucleus was 0.41 ± 0.51 before and 6.19 ± 1.80 after radioiodine therapy, and this difference was statistically significant (P = 0.001 < 0.05). Absorbed doses estimated for the 15 patients were 0.77 ± 0.31 Gy applying standard line in vitro external radiation doses.γ-H2AX foci immunodetection in lymphocytes may detect radiation-induced DNA damage associated with I-131 therapy for thyroid cancer, and may facilitate estimation of the radiation doses absorbed with this therapy.
Keywords: Radioiodine-131 therapy; γ-H2AX; DNA damage; Radiotoxicity

Long-term changes of aortic 18F-FDG uptake and calcification in health-screening subjects by Yoshiharu Ryu; Katsuya Yoshida; Yoshifumi Suzuki; Masashi Nakadate; Isao Umehara; Makoto Tomita; Hitoshi Shibuya (239-246).
We investigated long-term changes in aortic 18F-fluorodeoxyglucose (18F-FDG) uptake and calcification in health-screening subjects and their relation with atherogenic risk factors.A total of 94 consecutive subjects (72 men, 22 women; age 47–85 years, mean 57.9 years) participating in a health-screening protocol were evaluated retrospectively. All subjects had follow-up PET/CT scans 3.0–5.8 years (mean 4.1 years) later. We measured 18F-FDG uptake (maximum SUV) and calcium score (Agatston score) of the ascending, descending thoracic and infrarenal abdominal aorta on PET/CT images. 18F-FDG uptake and calcium score of the whole aorta (FUWA and CSWA) increased significantly in the follow-up study compared with the initial study (p = 0.02 and p < 0.0001, respectively). Multiple regression analysis showed that the change in FUWA per year was significantly associated with visceral fat area, while the change of CSWA per year was significantly associated with age and smoking habit. The degrees of 18F-FDG uptake and calcium score increases were significantly greater in the abdominal aorta than in the thoracic aorta (p = 0.05 and p < 0.0001, respectively).Our data demonstrated the longitudinal progressions of vascular inflammation and calcification of health-screening subjects. Inflammation and calcification were observed to progress significantly faster in the abdominal aorta than in the thoracic aorta. The progressions of vascular inflammation and calcification may be associated with different atherogenic risk factors.
Keywords: Atherosclerosis; Risk factors; Vascular inflammation; Vascular calcification; Positron emission tomography

A videofluoroscopic swallowing study (VFSS) is generally used to assess dysphagia and aspiration, although false-negative results may be obtained. Saliva aspiration may cause false-negative VFSS findings in elderly people. A radionuclide salivagram can be useful in detecting saliva aspiration. We therefore compared these two methods for the evaluation of patients with aspiration pneumonia.We prospectively enrolled 50 patients with aspiration pneumonia into this study. All patients underwent VFSS, and were evaluated on the Penetration-Aspiration Scale. A salivagram was performed on the day after VFSS and each patient received 1 mL Tc-99 m DTPA sublingually. Both dynamic and delayed images were obtained.Aspiration was observed in 34 % of patients by salivagram and in 42 % by VFSS. The frequency of tests that were positive for aspiration pneumonia using a combination of the two methods was 52 %. Five patients with positive aspiration findings on salivagram were negative on VFSS. The association between VFSS and salivagram findings was significant but the total agreement was 72 %. The frequency of aspiration pneumonia was significantly associated with an abnormal salivagram finding.A salivagram may be a useful method for the evaluation of aspiration in elderly people, and a combination of the VFSS and salivagram methods could enable a more effective investigation of aspiration pneumonia.
Keywords: Dysphagia; Pneumonia; Aspiration

Monte Carlo simulations and radiation dosimetry measurements of 142Pr capillary tube-based radioactive implant (CTRI): a new structure for brachytherapy sources by Mohamadreza K. Bakht; Mahdi Sadeghi; Seyed J. Ahmadi; Asghar Haddadi; Soudeh S. Sadjadi; Claudio Tenreiro (253-260).
Previously, a promising $$ {eta^- } $$ -emitting praseodymium-142 glass seed was proposed for brachytherapy of prostate cancer. In accordance with the previous study, a 142Pr capillary tube-based radioactive implant (CTRI) was suggested as a source with a new structure to enhance application of $$ {eta^- } $$ -emitting radioisotopes such as 142Pr in brachytherapy.Praseodymium oxide powder was encapsulated in a glass capillary tube. Then, a thin and flexible fluorinated ethylene propylene Teflon® layer sealed the capillary tube. The source was activated in the Tehran Research Reactor by the 141Pr(n,γ) 142Pr reaction. Measurements of the dosimetric parameters were performed using GafChromic® radiochromic film. In addition, the dose rate distribution of 142Pr CTRI was calculated by modeling 142Pr source in a water phantom using Monte Carlo N-Particle Transport (MCNP5) Code.The active source was unreactive and did not leak in water. In comparison with the earlier proposed 142Pr seed, the suggested source showed similar desirable dosimetric characteristics. Moreover, the 142Pr CTRI production procedure may be technically and economically more feasible. The mass of praseodymium in CTRI structure could be greater than that of the 142Pr glass seed; therefore, the required irradiation time and the neutron flux could be reduced.A 142Pr CTRI was proposed for brachytherapy of prostate cancer. The dosimetric calculations by the experimental measurements and Monte Carlo simulation were performed to fulfill the requirements according to the American Association of Physicists in Medicine recommendations before the clinical use of new brachytherapy sources. The characteristics of the suggested source were compared with those of the previously proposed 142Pr glass seed.
Keywords: Dosimetry; Monte Carlo modeling; Praseodymium-142; Prostate brachytherapy

Differentiation of tumor recurrence from radiation-induced pulmonary fibrosis after stereotactic ablative radiotherapy for lung cancer: characterization of 18F-FDG PET/CT findings by Naomi Nakajima; Yoshifumi Sugawara; Masaaki Kataoka; Yasushi Hamamoto; Takashi Ochi; Shinya Sakai; Tadaaki Takahashi; Makoto Kajihara; Norihiro Teramoto; Motohiro Yamashita; Teruhito Mochizuki (261-270).
Stereotactic ablative radiotherapy (SABR), also known as stereotactic body radiotherapy (SBRT), is now a standard treatment option for patients with stage I non-small cell lung cancer or oligometastatic lung tumor who are medically inoperable or medically operable but refuse surgery. When mass-like consolidation is observed on follow-up CT after SABR, it is sometimes difficult to differentiate tumor recurrence from SABR-induced pulmonary fibrosis. In this study, we evaluated the role of 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) in differentiating tumor recurrence from radiation fibrosis after SABR.Between June 2006 and June 2009, 130 patients received SABR for stage I non-small cell lung cancer or metastatic lung cancer at our institution. Fifty-nine patients of them were imaged with FDG-PET/CT after SABR. There were a total of 137 FDG-PET/CT scans for retrospective analysis. The FDG uptake in the pulmonary region was assessed qualitatively using a 3-point scale (0, none or faint; 1, mild; or 2, moderate to intense), and the shape (mass-like or non mass-like) was evaluated. For semi-quantitative analysis, the maximum standardized uptake value (SUVmax) was calculated.Sixteen of 59 patients had local failure. In recurrent tumor, the combination of intensity grade 2 and mass-like shape was most common (21/23; 91 %). By contrast, in cases of radiation fibrosis, the combination of intensity grade 0 or 1 and non mass-like shape was most common (48/59; 81 %). The SUVmax of tumor recurrence after 12 months was significantly higher than that of radiation fibrosis (8.0 ± 3.2 vs. 2.1 ± 0.9, p < 0.001), and all tumor recurrence showed the SUVmax > 4.5 at diagnosis of local failure. At ≥12 months after SABR, these two variables, the combination of intensity 2 and mass-like FDG uptake or SUVmax > 4.5 acquired a significant high predictive value of local recurrence, finding sensitivity 100 % and specificity 100 % for both of them.The combination of FDG uptake patterns and SUVmax was useful for distinguishing tumor recurrence from radiation fibrosis after SABR.
Keywords: FDG-PET/CT; Stereotactic ablative radiotherapy; Lung cancer; Radiation fibrosis; Tumor recurrence

Appropriate collimators in a small animal SPECT scanner with CZT detector by Yusuke Higaki; Masato Kobayashi; Tomoya Uehara; Hirofumi Hanaoka; Yasushi Arano; Keiichi Kawai (271-278).
Almost all small animal SPECT is performed with pinhole collimators (PH), including single-PH (SPH) and multi-PH (MPH). In the clinical study, not only PH but also parallel-hole collimator (PAH) is often used in planar and SPECT imaging. However, there have been no comparative studies on image quality with various collimators on the small animal imaging. This study compared the basic characteristics of PH and PAH in small animal imaging.Performance of planar and SPECT images was evaluated using 99mTcO4 and SPH, MPH and PAH with low energy and high resolution on the SPECT/CT scanner FX3200. We measured sensitivity, resolution, concentration linearity and uniformity. Planar imaging of mice with 99mTc-labeled mercaptoacetyltriglycine (99mTc-MAG3) was performed using SPH and PAH. SPECT imaging with 99mTc-methylene diphosphonate (99mTc-MDP) was performed using all collimators.With SPH, MPH and PAH, sensitivity was 43.5, 211.2 and 926.5 cps/MBq, respectively, and spatial resolution was 0.60/0.56, non/0.96, 5.20/5.34 mm full-width half maximum (planar/SPECT), respectively. There were marked correlations between the radioactivity counts on images and radioactivity with all collimators. Values of % standard deviation on planar imaging showed small differences between the SPH and PAH, while the values were the smallest on SPECT imaging with MPH. On imaging of mice, SPH yielded high-quality 99mTc-MAG3-planar images when compared with PAH. MPH yielded sharper 99mTc-MDP-SPECT images than SPH and PAH.The characteristics of PH and PAH differed on small animal imaging. Although sensitivity was higher with PAH, PH showed higher resolution. Among the PH collimators, SPH was more appropriate for planar imaging, and MPH was more suitable for SPECT imaging in a small animal imaging scanner with CZT detector.
Keywords: Small animal imaging; Planar imaging; SPECT imaging; Pinhole collimator; Parallel-hole collimator

Pharmacokinetic model of myocardial 99mTc-sestamibi washout by Tsubasa Watanabe; Hajime Monzen; Masatake Hara; Takashi Mizowaki; Masahiro Hiraoka (279-284).
Technetium-99m sestamibi (99mTc-MIBI) scintigraphy has been reported to be a functional imaging tool for in vivo detection of mitochondrial dysfunction in myocardium and multidrug resistance-associated protein expression in tumors. The purpose of this study was to propose a clinically applicable pharmacokinetic model with metabolic equilibrium of 99mTc-MIBI and to evaluate the accuracy of the model.For this study, eight healthy men received 99mTc-MIBI scintigraphy. The planar images were obtained at 0.25, 0.5, 1, 2, 3, 4, 5, and 6 h after 99mTc-MIBI injection. The measured time series 99mTc-MIBI counts were fitted to our model by nonlinear regression analysis. The predictive performance of the model was determined by comparing the residuals between measured and predicted values.We obtained a good regression by fitting data from 0.25 to 6 h after 99mTc-MIBI injection, with excellent correlation between measured and predicted 99mTc-MIBI counts (R 2 = 0.9792) and a slope near unity. The 95 % confidence interval of the mean prediction error included 0, which means that the prediction was not significantly biased. The precision of the prediction was also excellent.Our model shows good predictive capacity, with favorable bias and accuracy. By comparing the predictive values of this model with measured values, mitochondrial 99mTc-MIBI washout can be quantified. 99mTc-MIBI washout rates are reported to be a promising method for evaluating cardiac function in patients with cardiac diseases and P-glycoprotein expression in tumor cells. Therefore, this quantification could be useful for mitochondrial functional imaging, especially in patients with cardiac diseases or tumors.
Keywords: Mitochondria; 99mTc-sestamibi; Washout; P-glycoprotein; Functional imaging

Direct comparison of radiation dosimetry of six PET tracers using human whole-body imaging and murine biodistribution studies by Muneyuki Sakata; Keiichi Oda; Jun Toyohara; Kenji Ishii; Tadashi Nariai; Kiichi Ishiwata (285-296).
We investigated the whole-body biodistributions and radiation dosimetry of five 11C-labeled and one 18F-labeled radiotracers in human subjects, and compared the results to those obtained from murine biodistribution studies.The radiotracers investigated were 11C-SA4503, 11C-MPDX, 11C-TMSX, 11C-CHIBA-1001, 11C-4DST, and 18F-FBPA. Dynamic whole-body positron emission tomography (PET) was performed in three human subjects after a single bolus injection of each radiotracer. Emission scans were collected in two-dimensional mode in five bed positions. Regions of interest were placed over organs identified in reconstructed PET images. The OLINDA program was used to estimate radiation doses from the number of disintegrations of these source organs. These results were compared with the predicted human radiation doses on the basis of biodistribution data obtained from mice by dissection.The ratios of estimated effective doses from the human-derived data to those from the mouse-derived data ranged from 0.86 to 1.88. The critical organs that received the highest absorbed doses in the human- and mouse-derived studies differed for two of the six radiotracers. The differences between the human- and mouse-derived dosimetry involved not only the species differences, including faster systemic circulation of mice and differences in the metabolism, but also measurement methodologies.Although the mouse-derived effective doses were roughly comparable to the human-derived doses in most cases, considerable differences were found for critical organ dose estimates and pharmacokinetics in certain cases. Whole-body imaging for investigation of radiation dosimetry is desirable for the initial clinical evaluation of new PET probes prior to their application in subsequent clinical investigations.
Keywords: Radiation dosimetry; PET; Whole-body distribution

18F-FDG-PET/CT predicts survival in hypopharyngeal squamous cell carcinoma by Hidenori Suzuki; Katsuhiko Kato; Yasushi Fujimoto; Yoshiyuki Itoh; Mariko Hiramatsu; Takashi Maruo; Shinji Naganawa; Yasuhisa Hasegawa; Tsutomu Nakashima (297-302).
We investigated the relationship between overall survival of patients and pretreatment [18F]-2-fluorodeoxyglucose (18F-FDG) uptake, assessed by positron emission tomography combined with computed tomography (PET/CT) in hypopharyngeal squamous cell carcinoma.Thirty-one patients who were newly diagnosed as resectable hypopharyngeal squamous cell carcinoma underwent pretreatment 18F-FDG-PET/CT. We used the maximum standardized uptake value (SUVmax) as 18F-FDG uptake. Overall survival rate was calculated by the Kaplan–Meier method.The median SUVmax was 11.53 (range 2.49–22.33). Patients with SUVmax ≥ 13 significantly exhibited shorter overall survival in univariate analysis (p < 0.01). Moreover, by Cox proportional hazards model of multivariate analysis, SUVmax ≥ 13 was a significant prognostic factor independent of clinical T and N classification, and treatment group (p < 0.02).These results suggested that SUVmax obtained by pretreatment 18F-FDG PET/CT assessment is an important prognostic factor in patients with hypopharyngeal squamous cell carcinoma.
Keywords: 18F-FDG-PET/CT; Hypopharyngeal; Squamous; Cell; Carcinoma; SUVmax

SPG3A-linked hereditary spastic paraplegia associated with cerebral glucose hypometabolism by Tatsuhiro Terada; Satoshi Kono; Yasuomi Ouchi; Kenichi Yoshida; Yasushi Hamaya; Shigeru Kanaoka; Hiroaki Miyajima (303-308).
SPG3A-linked hereditary spastic paraplegia (HSP) is a rare autosomal dominant motor disorder caused by a mutation in the SPG3A gene, and is characterized by progressive motor weakness and spasticity in the lower limbs, without any other neurological abnormalities. SPG3A-linked HSP caused by a R239C mutation has been reported to present a pure phenotype confined to impairment of the corticospinal tract. However, there is still a debate about the etiology of this motor deficit with regard to whether it is peripheral or central. We herein report two patients who were heterozygous for a R239C mutation in the SPG3A gene. Two middle-aged Japanese sisters had been suffering from a pure phenotype of HSP since their childhood. Both patients had a significant decrease in glucose metabolism in the frontal cortex medially and dorsolaterally in a [18F]-fluorodeoxyglucose (FDG) positron emission photography (PET) study and low scores on the Frontal Assessment Battery. A real-time PCR analysis in normal subjects showed the frontal cortex to be the major location where SPG3A mRNA is expressed. The present finding that the frontal glucose hypometabolism was associated with frontal cognitive impairment indicates that widespread neuropathology associated with mutations in the SPG3A gene may be present more centrally than previously assumed.
Keywords: PET; SPG3A ; Atlastin; Frontal Assessment Battery