• Title/Summary/Keyword: resonance signal

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Gastric Metastasis from Gastric-Type Mucinous Adenocarcinoma of Uterine Cervix: A Case Report (자궁경부 위형 점액샘암종의 위 전이: 증례 보고)

  • Min Hye Kim;Kyeong Ah Kim;Yi Kyeong Chun;Jeong Woo Kim;Jongmee Lee;Chang Hee Lee
    • Journal of the Korean Society of Radiology
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    • v.85 no.2
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    • pp.445-450
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    • 2024
  • Gastric metastasis (GM) from cervical cancer is extremely rare, and only a few cases have been reported in the English literature. Gastric-type mucinous adenocarcinomas (GAS) of the uterine cervix are rare. GAS is an aggressive cancer commonly found in advanced stages; however, GM has not been reported. This study presents a rare case of GM from GAS of the uterine cervix in a 61-year-old female and describes the radiological findings of both the GM and cervical mucinous adenocarcinoma. GM appeared as a poor enhancing submucosal mass. The cervical mucinous adenocarcinoma appeared as an infiltrating mass with poor contrast enhancement. It exhibited mildly high and low signal intensities on the diffusion-weighted image and apparent diffusion coefficient map, respectively. This case is extremely rare and challenging to diagnose; however, if cervical cancer is an human papillomavirus-independent GAS type and a submucosal lesion is found in the stomach, the possibility of metastasis with a pattern similar to our case could be considered.

Imaging of Sequestered Lumbar Discs (요추 분리추간판의 영상 소견)

  • Gangwon Jeong;Heecheol Park;Sun Joo Lee;Dae-Hyun Park;Sung Hwa Paeng;Eugene Lee
    • Journal of the Korean Society of Radiology
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    • v.85 no.1
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    • pp.3-23
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    • 2024
  • Intervertebral disc herniation is frequently encountered in radiological practice. Sequestered disc herniation occurs when the disc material undergoes degeneration and completely loses continuity with the parent nucleus pulposus. Sequestered discs can reside within and outside the spinal canal, exerting a mass effect on adjacent structures, compressing nerve pathways, and eliciting a range of clinical symptoms. In particular, sequestered discs within the dura cannot be identified without durotomy. Therefore, precise preoperative localization is crucial for surgical planning. On MRI, the signal intensity of the sequestered disc may vary due to independent degeneration processes. Additionally, most sequestered disc fragments show varying degrees of peripheral enhancement depending on the degree of angiogenesis and granulation around the isolated tissue. In this article, we review various imaging findings and the location of the sequestered disc to provide patients with an accurate diagnosis and appropriate treatment direction.

Selection of TI for Suppression Fat Tissue of SPAIR and Comparative Study of SPAIR and STIR of Brain Fast SE T2 Weighted Imaging (뇌의 고속스핀에코 T2강조영상에서 지방조직 억제를 위한 SPAIR의 반전시간(TI) 결정 및 STIR 영상과의 비교 연구)

  • Lee, Hoo-Min;Kim, Ham-Gyum;Kong, Seok-Kyo
    • Journal of radiological science and technology
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    • v.32 no.1
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    • pp.95-99
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    • 2009
  • The purpose of this research is to seek SPAIR's reversal time (TI) which satisfies two conditions ; maintaining the suppression ability of fat tissue and simultaneously minimizing the inhomogeneity of fat tissue in T2 high-speed spin echo 3.0T magnetic resonance image (MRI) of the brain, and to compare SPAIR with STIR which is fat-suppression technique. The reversal times (TI) of SPAIR protocol are set to 1/2, 1/3, 1/6 and 1/12 of SPAIR TR (420 msec), namely 210 msec (8 people), 140 msec (26 people), 70 msec (26 people) and 35 msec (18 people) and STIR TI is set with 250 msec (26 people). With these parameter sets, we acquired the axis direction 104 images of the brain. In ROI ($50\;mm^2$) of output image, signal intensities of the fatty tissue, the muscular tissue, and the background were measured and the CNRs of fatty tissue and the muscular tissue were calculated. The inhomogeneity of the fatty tissue is SD/mean, where SD is the standard deviation and 'mean' is a average fatty tissue signal. Consequently, SPAIR TI is determined on either 1/3 or 1/6 of TR (420 ms) ; 140 ms or 70 ms. Because the difference of statistics in fat-suppression ability and inhomogeneity of fatty tissue is very small (p < 0.001), Selecting 140 ms seems to be better choice for the image quality. Meanwhile, Comparing SPAIR (TI : 140 ms) with STIR, the fat-suppression is not able to be considered statistically (p < 0.252), but the image quality is able to be considered statistically (p < 0.01). In conclusion, SPAIR is better than STIR in the image quality.

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Quantitative Assessment using SNR and CNR in Cerebrovascular Diseases : Focusing on FRE-MRA, CTA Imaging Method (뇌혈관 질환에서 신호대 잡음비와 대조도대 잡음비를 이용한 정량적평가 : FRE-MRA, CTA 영상기법중심으로)

  • Goo, Eun-Hoe
    • Journal of the Korean Society of Radiology
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    • v.11 no.6
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    • pp.493-500
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    • 2017
  • In this study, data analysis has been conducted by INFINITT program to analyze the effect of signal to noise ratio(SNR) and contrast to noise ratio(CNR) of flow related enhancement(FRE) and computed tomography Angiography(CTA) on cerebrovascular diseases for qualitative evaluations. Based on the cerebrovascular image results achieved from 63 patients (January to April, 2017, at C University Hospital), we have selected 19 patients that performed both FRE-MRA and CTA. From the 19 patients, 2 were excluded due to artifacts from movements in the cerebrovascular image results. For the analysis conditions, we have set the 5 part (anterior cerebral artery, right and left Middle cerebral artery, right and left Posterior cerebral artery) as the interest area to evaluate the SNR and CNR, and the results were validated through Independence t Test. As a result, by averaging the SNR, and CNR values, the corresponding FRE-MRA achieved were: anterior cerebral artery ($1500.73{\pm}12.23/970.43{\pm}14.55$), right middle cerebral artery ($1470.16{\pm}11.46/919.44{\pm}13.29$), left middle cerebral artery ($1457.48{\pm}17.11/903.96{\pm}14.53$), right posterior cerebral artery ($1385.83{\pm}16.52/852.11{\pm}14.58$), left posterior cerebral artery ($1318.52{\pm}13.49/756.21{\pm}10.88$). by averaging the SNR, and CNR values, the corresponding CTA achieved were: anterior cerebral artery ($159.95{\pm}12.23/123.36{\pm}11.78$), right middle cerebral artery ($236.66{\pm}17.52/202.37{\pm}15.20$), left middle cerebral artery ($224.85{\pm}13.45/193.14{\pm}11.88$), right posterior cerebral artery ($183.65{\pm}13.47/151.44{\pm}11.48$), left posterior cerebral artery ($177.7{\pm}16.72/144.71{\pm}11.43$) (p < 0.05). In conclusion, MRA had high SNR and CNR value regardless of the cerebral infarction or cerebral hemorrhage observed in the 5 part of the brain. Although FRE-MRA consumed longer time, it proved to have less side effect of contrast media when compared to the CTA.

Detection Characteristics of Gamma-Irradiated Seeds by using PSL, TL, ESR and GC/MS (PSL, TL, ESR 및 GC/MS 분석을 통한 감마선 조사된 유지종실류의 검지 특성 연구)

  • Kim, Kyu-Heon;Son, Jin-Hyok;Kang, Yoon-Jung;Park, Hye-Young;Kwak, Ji-Young;Lee, Jae-Hwang;Park, Yong-Chjun;Jo, Tae-Yong;Kim, Jae-I;Lee, Hwa-Jung;Lee, Sang-Jae;Han, Sang-Bae
    • Journal of Food Hygiene and Safety
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    • v.28 no.2
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    • pp.130-137
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    • 2013
  • In this study, we investigated the applicability of the photostimulated luminescence (PSL), thermoluminescence (TL), electron spin resonance (ESR) and gas chromatography/mass spectrometry (GC/MS) methods for 5 seeds which are not allowed to be irradiated in Korea. All 5 seeds including evening primrose seed, safflower seed, rape seed, sunflower seed and flax seed were analyzed. Samples were irradiated at 1~10 kGy using a $^{60}Co$ gamma-ray irradiator. In PSL study, the photon counts of all the unirradiated samples showed negative (lower than 700). The photon counts of irradiated (1, 5, 10 kGy) samples showed positive (higher than 5,000). In TL analysis, results showed that it is possible to apply TL method to all foods containing minerals. In ESR measurements, the ESR signal (single-line) intensity of irradiated foods was higher than non-irradiated foods. The hydrocarbons 1,7-hexadecadiene ($C_{16:2}$) and 8-heptadecene ($C_{17:1}$) from oleic acid were detected only in the irradiated samples before and after the treatment at doses ${\geq}$ 1 kGy, but they were not detected in non-irradiated samples before and after treatment. These two hydrocarbons could be used as markers to identify irradiated safflower seed, rape seed, Sunflower seed and flax seed. And then, the hydrocarbons 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$) from linoleic acid were detected in the evening primrose seed, safflower seed and sunflower seed. According to the results, PSL, TL and GC/MS methods were successfully applied to detect the irradiated foods. It is concluded that PSL, TL and GC/MS methods are suitable for detection of irradiated samples and a combined method is recommendable for enhancing the reliability of detection results.

The Comparative Analysis Study and Usability Assessment of Fat Suppressed 3D T2* weighted Technique and Fat Suppressed 3D SPGR Technique when Examining MRI for Knee Joint Cartilage Assesment (슬관절 연골 평가를 위한 자기공명영상 검사 시 지방 신호 억제 3D T2* Weighted 기법과 지방 신호 억제 3D SPGR 기법의 비교 및 유용성 평가)

  • Kang, Sung-Jin
    • Journal of the Korean Magnetics Society
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    • v.26 no.6
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    • pp.219-225
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    • 2016
  • In this study, for assessment of degenerative knee joint cartilage disease we acquired images by fat suppressed 3D spoiled gradient recalled (SPGR) and fat suppressed 3D $T2^*$ weighted imaging techniques. To do a quantitative evaluation, the knee joint cartilage was divided into medial femoral cartilage (MFC), medial tibial cartilage (MTC), lateral femoral cartilage (LFC), lateral femoral cartilage (LFC) and patella cartilage (Pat) to measure their respective signal intensity values, signal-to-noise ratio, and contrast-to-noise ratio. As for the measured values, statistical significance between two techniques was verified by using Mann-Whitney U-Test. To do a qualitative evaluation, two radiologists have examined images by techniques after which image artifact, cartilage surface, tissue contrast, and depiction of lesion distinguishing were evaluated based on 4-point scaling (1: bad, 2: appropriate, 3: good, 4: excellent), and based on the result, statistical significance was verified by using Kappa-value Test. 3.0T MR system and HD T/R 8ch knee array coil were used to acquire images. As a result of a quantitative analysis, based on SNR values measured by using two imaging techniques, MFC, LFC, LTC, and Pat showed statistical significance (p < 0.05), but MTC did not (p > 0.05). As a result of verifying statistical significance for measured CNR value, MFC, LFC, and Pat showed statistical significance (p < 0.05), while MTC and LTC did not show statistical significance (p > 0.05). As a result of a qualitative analysis, by comparing mean values for evaluated image items, 3D $T2^*$ weighted Image has indicated a slightly higher value. As for conformance verification between the two observers by using Kappa-value test, all evaluated items have indicated statistically significant results (p < 0.05). 3D $T2^*$ weighted technique holds a clinical value equal to or superior to 3D SPGR technique with respect to evaluating images, such as distinguishing knee joint cartilages, comparing nearby tissues contrast, and distinguishing lesions.

Correlation Analysis of Diffusion Metrics (FA and ADC) Values Derived from Diffusion Tensor Magnetic Resonance Imaging in Breast Cancer (유방암의 확산텐서 자기공명 영상에서 유도된 확산 지표(FA, ADC) 값의 연관성 분석)

  • Lee, Jae-Heun;Lee, Hyo-Yeong
    • Journal of the Korean Society of Radiology
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    • v.12 no.6
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    • pp.755-762
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    • 2018
  • The purpose of this study was to compare the FA(faractional anisotropy) and ADC(apparent diffusion coefficient) values, which were derived from diffusion tensor imaging in breast cancer patients. The diffusion gradient used in this study was derived from quantitative diffusion indices using 20 directions(b-value, 0 and $1,000s/mm^2$). Quantitative analysis was analyzed using Pearson's correction and qualitative analysis using for correction coefficients. As a result, $FA_{min}$, $FA_{mean}$ and $FA_{max}$ were $0.098{\pm}0.065$, $0.302{\pm}0.142$ and $0.634{\pm}0.236$, respectively(p > 0.05). The $ADC_{min}$, $ADC_{mean}$ and $ADC_{max}$ were $0.741{\pm}0.403$, $1.095{\pm}0.394$ and $1.530{\pm}0.447$, respectively(p > 0.05). The $FA_{min}$, $FA_{mean}$, and $FA_{max}$ mean values were $0.132{\pm}0.050$, $0.418{\pm}0.094$, and $0.770{\pm}0.164$ for Category 6 and Kinetic Curve Pattern III, respectively. $ADC_{min}$, $ADC_{mean}$, and $ADC_{max}$ were $0.753{\pm}0.189$, $1.120{\pm}0.236$, and $1.615{\pm}0.372$, respectively. Quantitative analysis showed negative correlation between $ADC_{mean}-FA_{mean}$ and $ADC_{max}-FA_{max}$(p = 0.001, 0.003). The qalitative analysis showed ADC 0.628(p = 0.001), FA 0.620(p = 0.001) in the internal evaluations, ADC 0.677(p = 0.001), FA 0.695(p = 0.001) in external evaluations. In conclusion, based on the morphological examination, time to signal intensity graph is the form of wash-out(pattern III) in the dynamic contrast enhance examination, As a result, the $ADC_{mean}$ $1.120{\pm}0.236$ and $FA_{mean}$ values were $0.032{\pm}0.142$ with a negative correlation (Y=1.44-1.12X). Therefore, If we understand the shape of time to signal intensity graph and the relationship between ADC and FA, It will be a criterion for distinguishing malignant diseases in breast cancer.

Reduction of Artifacts in Magnetic Resonance Imaging with Diamagnetic Substance (반자성 물질을 이용한 자기공명영상검사에서의 인공물 감소)

  • Choi, Woo Jeon;Kim, Dong Hyun
    • Journal of the Korean Society of Radiology
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    • v.13 no.4
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    • pp.581-588
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    • 2019
  • MRI is superior when contrasted to help the organization generate artifacts resolution, but also affect the diagnosis and create a image that can not be read. Metal is inserted into the tooth, it is necessary to often be inhibited in imaging by causing the geometric distortion due to the majority and if the difference between the magnetic susceptibility of a ferromagnetic material or paramagnetic reducing them. The purpose of this study is to conduct a metal artefact in accordance with the analysis using a diamagnetic material. The magnetic material include a wire for the orthodontic bracket and a stainless steel was used as a diamagnetic material was used copper, zinc, bismuth. Testing equipment is sequenced using 1.5T, 3T was used was measured using a SE, TSE, GE, EPI. A self-produced phantom material was used for agarose gel (10%) to a uniform signal artifacts causing materials are stainless steel were tested by placing in the center of the phantom and cover inspection of the positive cube diamagnetic material of 10mm each length.After a measurement artefact artifact zone settings area was calculated using the Wand tool After setting the Low Threshold value of 10 in the image obtained by subtracting images, including magnetic material from a pure tool phantom images using Image J. Metal artifacts occur in stainless steel metal artifact reduction was greatest in the image with the bismuth diamagnetic materials of copper and zinc is slightly reduced, but the difference in degree will not greater. The reason for this is thought to be due to hayeotgi offset most of the susceptibility in bismuth diamagnetic susceptibility of most small ferromagnetic. Most came with less artifacts in image of bismuth in both 1.5T and 3T. Sequence-specific artifact reduction was most reduced artifacts from the TSE 1.5T 3T was reduced in the most artifacts from SE. Signal-to-noise ratio was the lowest SNR is low, appears in the implant, the 1.5T was the Implant + Bi Cu and Zn showed similar results to each other. Therefore, the results of artifacts variation of diamagnetic material, magnetic susceptibility (${\chi}$) is the most this shows the reduced aspect lower than the implant artificial metal artifacts criteria in the video using low bismuth susceptibility to low material the more metal artifacts It was found that the decrease. Therefore, based on the study on the increase, the metal artifacts reduction for the whole, as well as dental prosthesis future orthodontic materials in a way that can even reduce the artifact does not appear which has been pointed out as a disadvantage of the solutions of conventional metal artifact It is considered to be material.

Correlation Analysis between Fat Fraction and Bone Mineral Density Using the DIXON Method for Fat Dominant Tissue in Knee Joint MRI: A Preliminary Study (지방우세 딕슨기법을 이용한 슬관절 자기공명영상 지방신호분율과 골밀도 간의 상관관계 분석: 예비 연구)

  • Sung Hyun An;Kyu-Sung Kwack;Sunghoon Park;Jae Sung Yun;Bumhee Park;Ji Su Kim
    • Journal of the Korean Society of Radiology
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    • v.84 no.2
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    • pp.427-440
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    • 2023
  • Purpose This study aimed to investigate the correlation between the fat signal fraction (FF) of the fat-dominant bone tissue of the knee joint, measured using the MRI Dixon method (DIXON) technique, and bone mineral density (BMD). Materials and Methods Among the patients who underwent knee DIXON imaging at our institute, we retrospectively analyzed 93 patients who also underwent dual energy X-ray absorptiometry within 1 year. The FFs of the distal femur metaphyseal (Fm) and proximal tibia metaphyseal (Tm) were calculated from the DIXON images, and the correlation between FF and BMD was analyzed. Patients were grouped based on BMD of lumbar spine (L), femoral neck (FN), and common femur (FT) respectively, and the Kruskal-Wallis H test was performed for FF. Results We identified a significant negative correlation between TmFF and FN-BMD in the entire patient group (r = -0.26, p < 0.05). In female patients, TmFF showed a negative correlation with FN-BMD, FT-BMD, and L-BMD (r = -0.38, 0.28 and -0.27, p < 0.05). In male patients, FmFF was negatively correlated with only FN-BMD and FT-BMD (r = -0.58 and -0.42, p < 0.05). There was a significant difference in the TmFF between female patients grouped by BMD (p < 0.05). In male patients, there was a significant difference in FmFF (p < 0.05). Conclusion Overall, we found that FF and BMD around the knee joints showed a negative correlation. This suggests the potential of FF measurement using DIXON for BMD screening.

The Comparative Imaging Study on Mn-phthalocyanine and Mangafodipir trisodium in Experimental VX2 Animal Model (실험적으로 유발시킨 VX2 동물모델에서의 Mn-phthalocyanine과 Mangafodipir trisodium의 비교영상)

  • Park Hyun-Jeong;Ko Sung-Min;Kim Yong-Sun;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.32-41
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    • 2004
  • Purpose : To measure the NMR relaxation properties of MnPC, to observe the characteristics of liver enhancement patterns on MR images in experimentally implanted rabbit VX2 tumor model, and to estimate the possibility of tissue specific contrast agent for MnPC in comparison with the hepatobiliary agent. Materials and Methods : Phthalocyanine (PC) was chelated with paramagnetic ions, manganese (Mn). 2.01 g (5.2 mmol) of phthalocyanine was mixed with 0.37 g (1.4 nlmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography ($CHCl_3:\;CH_3OH=98:2$, volume ratio) to obtain 1.04 g $(46\%)$ of MnPC (molecular weight = 2000 daltons). The T1/T2 relaxivity (R1/R2) for MnPC were determined at a 1.5 T (64 MHz) MR spectrometer. VX2 tumor model was experimentally implanted in the liver parenchyma of rabbits. All MR studies were performed on 1.5 T. The human extremity radio frequency coil of a bird cage type was employed. MR images were acquired at 17 to 24 days after VX2 carcinoma implantation.4 mmol/kg MnPC and 0.01 mmol/kg Mn-DPDP were injected via the ear vein of rabbits. T1-weighted images were obtained with spin-echo (TR/TE=516/14 msec) and fast multiplanar spoiled gradient recalled (TR/TE : 80/4 msec, $60^{\circ}$ flip angle) pulse sequence. Fast spin-echo (TR/TE=1200/85 msec) was used to obtain the T2-weighted images. Results : The value of T1/T2 relaxivity (R1/R2) of MnPC was $7.28\;mM^{-1}S^{-1}$ and $55.56\;mM^{-1}S^{-1}$ respectively at 1.5 T (64 MHz). Because the T2 relaxivity of MnPC that bonded strongly, covalently manganese with phthalocyanine was very high, the signal intensity of liver parenchyma was decreased on postcontrast T2-weighted images and we could easily distinguish the VX2 carcinoma within the liver parenchyma. When MnPC was administrated intravenously, the tumor margin delineation was more remarkable than Mn-DPDP-enhanced images. The enhancement of liver parenchyma with MnPC persisted at relatively high levels over at least one hour after injection of the contrast agents. Conclusion : The hepatic uptake and biliary excretion of MnPC, which are similar to Mn-DPDP, suggest that this agent is a new liver-specific agent. Also, MnPC seems to be used as a dual contrast agent (T1 and T2) with high T2 relaxivity. However, it is warranted that MnPC needs further investigation as a potential contrast agent for MR imaging of the liver. That is, further characterizations of MnPC are needed in vivo and in vitro before clinical trials. The diagnostic potential of MnPC will also have to be examined more in the animal models of additional types.

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