{"created":"2023-05-15T14:56:57.324986+00:00","id":77293,"links":{},"metadata":{"_buckets":{"deposit":"2d70beac-fbd6-429e-85c5-4f8f8c7c61e3"},"_deposit":{"created_by":1,"id":"77293","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"77293"},"status":"published"},"_oai":{"id":"oai:repo.qst.go.jp:00077293","sets":["10:28"]},"author_link":["797531","797537","797543","797540","797532","797530","797528","797534","797529","797538","797541","797536","797539","797542","797544","797527","797533","797535"],"item_10005_date_7":{"attribute_name":"発表年月日","attribute_value_mlt":[{"subitem_date_issued_datetime":"2019-10-30","subitem_date_issued_type":"Issued"}]},"item_10005_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Brain PET imaging plays key roles in neurology, neuro-oncology, and molecular imaging research fields. To fulfill a growing demand for a high-sensitivity, high-resolution, low-cost and compact brain PET system, we have proposed a helmet-shape detector arrangement. In the 2016 conference, we described development of the first prototype, which had depth-of-interaction (DOI) detectors without time-of-flight (TOF) capability. Last year, we reported the second prototype which had TOF capability of a 245-ps coincidence timing resolution without DOI capability. The crystal thickness was optimized through simulation so as to reduce the parallax error while keeping the gain in image quality. The detector was composed of 12×12 lutetium fine silicate (LFS) scintillation crystals (4×4×10 mm3) connected to a 12×12 multi-pixel photon counter (MPPC) array with one-to-one coupling.  In this work, we have evaluated performance of the second prototype based on the NEMA NU2 standards and compared the results with those of the first prototype. The values measured with the first (DOI) and second (TOF) prototypes were: spatial resolutions of 2.8 and 4.3 mm at the central position (1-cm offset) by the filtered back-projection method; sensitivities of 13.4 and 4.1 kcps/MBq; scatter fractions at the low activity of 31% and 31%; and peak noise-equivalent count rates (NECR) of 20.0 kcps at 2.6 kBq/mL and 18.6 kcps at 9.0 kBq/mL. With a TOF sensitivity gain of 5.4 (= 20 cm diameter / 3.675 cm TOF localization), effective sensitivity and effective peak NECR were 22.3 kcps/MBq and 101.2 kcps at 9.0 kBq/mL for the second prototype. In the image quality assessment, the second prototype outperformed the first prototype. Although the first prototype had better performance for spatial resolution and sensitivity themselves which were measured with low count rate, the TOF capability of the second prototype worked well to reduce the random ratio, which resulted in the superior image quality.","subitem_description_type":"Abstract"}]},"item_10005_description_6":{"attribute_name":"会議概要（会議名, 開催地, 会期, 主催者等）","attribute_value_mlt":[{"subitem_description":"2019 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","subitem_description_type":"Other"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"metadata only access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_14cb"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Akamatsu, Go"}],"nameIdentifiers":[{"nameIdentifier":"797527","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Yoshida, Eiji"}],"nameIdentifiers":[{"nameIdentifier":"797528","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Tashima, Hideaki"}],"nameIdentifiers":[{"nameIdentifier":"797529","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Iwao, Yuma"}],"nameIdentifiers":[{"nameIdentifier":"797530","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Wakizaka, Hidekatsu"}],"nameIdentifiers":[{"nameIdentifier":"797531","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Maeda, Takamasa"}],"nameIdentifiers":[{"nameIdentifier":"797532","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Takahashi, Miwako"}],"nameIdentifiers":[{"nameIdentifier":"797533","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Yamashita, Taichi"}],"nameIdentifiers":[{"nameIdentifier":"797534","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Yamaya, Taiga"}],"nameIdentifiers":[{"nameIdentifier":"797535","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Akamatsu, Go","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797536","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Yoshida, Eiji","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797537","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Tashima, Hideaki","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797538","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Iwao, Yuma","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797539","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Wakizaka, Hidekatsu","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797540","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Maeda, Takamasa","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797541","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Takahashi, Miwako","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797542","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Yamashita, Taichi","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797543","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Yamaya, Taiga","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"797544","nameIdentifierScheme":"WEKO"}]}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"conference object","resourceuri":"http://purl.org/coar/resource_type/c_c94f"}]},"item_title":"DOI vs. TOF: performance comparison of two helmet-type PET prototypes based on the NEMA NU2 standards","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"DOI vs. TOF: performance comparison of two helmet-type PET prototypes based on the NEMA NU2 standards"}]},"item_type_id":"10005","owner":"1","path":["28"],"pubdate":{"attribute_name":"公開日","attribute_value":"2019-10-02"},"publish_date":"2019-10-02","publish_status":"0","recid":"77293","relation_version_is_last":true,"title":["DOI vs. TOF: performance comparison of two helmet-type PET prototypes based on the NEMA NU2 standards"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-15T23:53:05.527873+00:00"}