JIEN SAITO

Dr. JIEN SAITO

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 July 2023 in Neurology and Clinical Neuroscience
Verified
Journal Article
Closed access
YIYuji Isono
Yuji Isono
YKYuya Kano
Yuya Kano
KYKentaro Yamada
Kentaro Yamada
MMMasahiro Muto
Masahiro Muto
JSJIEN SAITO
JIEN SAITO
NMNoriyuki Matsukawa
Noriyuki Matsukawa

1 January 2024 in Annals of Vascular Diseases
Verified
Journal Article
Open access
PDF file
SHShunta Hayakawa
Shunta Hayakawa
JSJIEN SAITO
JIEN SAITO
SKShinji Kamiya
Shinji Kamiya
YSYoshiaki Sone
Yoshiaki Sone
YNYukihide Numata
Yukihide Numata
HSHideki Sasaki
Hideki Sasaki
Ruptured iliac artery aneurysms are serious conditions with high mortality, occasionally perforating into the venous system. A 73-year-old male presented with left leg edema and a pulsatile left lower abdominal mass. Computed tomography revealed a ruptured left common iliac artery aneurysm with perforation into the left common iliac vein. Additionally, bilateral internal iliac veins were noted to form an anomalous common trunk draining into the left common iliac vein. Treatment involved internal iliac vein balloon occlusion under fluoroscopy followed by open surgery for artificial graft replacement and fistula repair. The patient was discharged on the 8th postoperative day.

13 March 2024 in medRxiv
Verified
Preprint
Open access
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JSJIEN SAITO
JIEN SAITO
MMMasahiro Muto
Masahiro Muto
MTMasafumi Tada
Masafumi Tada
IYIsao Yokota
Isao Yokota
SKShinji Kamiya
Shinji Kamiya
SWSatoru Wakasa
Satoru Wakasa
Background Diffusion-weighted whole-body imaging with background body signal suppression is one of the whole-body magnetic resonance imaging techniques and is effective in diagnosing inflammatory and infectious diseases. We aimed to evaluate the diagnostic performance of this modality in infectious aortitis, which remains unclear. Methods The study participants were 32 patients with suspected infectious aortitis who underwent computed tomography and magnetic resonance imaging between September 2020 and November 2022. Sensitivity, specificity, and areas under the curve of each imaging modality were studied using a diagnosis based on a combination of imaging results, clinical symptoms, and laboratory tests. Decision curve analysis was performed to determine the benefit of adding magnetic resonance imaging to computed tomography. Results The median age was 74 years, and 23 participants were men. Fifteen patients (47%) were diagnosed with infectious aortitis. Positive findings for infectious aortitis were identified in 19, 18, and 14 patients by computed tomography, diffusion-weighted whole-body imaging, and the combination of both modalities, respectively. Sensitivity, specificity, and area under the curve for correct diagnosis were 93.3%, 70.6%, and 0.82 (95% confidence interval 0.69–0.95), respectively for computed tomography, 93.3%, 76.5%, and 0.85% (95% confidence interval 0.73%–0.97), respectively for diffusion-weighted imaging, and 86.7%, 94.1%, and 0.90 (95% confidence interval 0.80–0.10), respectively for the combination of both modalities. Decision curve analysis reinforced the clinical benefit of combining the two imaging modalities across all ranges of the probability thresholds. Conclusions Diffusion-weighted whole-body imaging with background body signal suppression is an effective diagnostic tool for infectious aortitis, especially when combined with computed tomography. Clinical Perspective Infectious aortitis is a serious disease that is difficult to accurately diagnose. Although PET-CT is associated with high diagnostic performance, limited access to this modality has encouraged the development of an alternative modality. The whole-body MRI with DWIBS is a more available modality, which is commonly used for cancer diagnosis but is also considered effective in diagnosing infectious diseases. The combination of DWIBS and non-contrast CT yielded a sensitivity of 86.7% (95% CI: 59.5–98.3%), a specificity of 94.1% (95% CI: 71.3–99.9%), and an AUC of 0.90 (95% CI: 0.80–0.10) for the diagnosis of infectious aortitis. DWIBS can be a useful modality as an alternative to PET-CT.

15 October 2026 in SSRN Electronic Journal
Verified
Preprint
Open access
JSJIEN SAITO
JIEN SAITO
TNTakayuki Nonoyama
Takayuki Nonoyama
YOYoshitaka Oda
Yoshitaka Oda
KYKoji Yamasaki
Koji Yamasaki
STSatonori Tsuneta
Satonori Tsuneta
SWSatoru Wakasa
Satoru Wakasa
Local weakness of the aortic wall can lead to dissection or rupture. Tensile testing loads a strip to rupture but gives one value for the whole strip. Micro-indentation maps local stiffness without damage, but its map is usually reduced to a mean. We asked whether the map's texture separates aneurysmal from non-aneurysmal wall and whether it tracks the tensile behavior of the same tissue. We studied 18 human ascending aortas (8 aneurysmal, 10 non-aneurysmal). We mapped the reduced modulus (Er) of each intimal surface by micro-indentation (582 points in total). We cut six tensile strips from each aorta (104 analyzed), matched each to one map band, and described each band by 22 texture features. Groups were compared at the patient level. Band-to-strip correspondence was tested within each aorta by Spearman correlation and leave-one-aorta-out cross-validation. Only the elastin-phase modulus Ee, the stiffness at low strain, was lower in aneurysmal aortas (p = 0.009); Er and its texture did not separate the groups. Within each aorta, five features tracked the collagen-phase modulus Ec, the stiffness at high strain. Bands whose map was stiffer, especially at its softest points, and varied more sharply from point to point had a lower Ec and a higher Ee/Ec ratio (|ρ| 0.27–0.43, FDR < 0.05). These relations held out of sample, explaining 5–13 % of the within-aorta variation. Ee showed no such relation. Paired at the same location, part of the wall's tensile behavior can be estimated from a non-destructive map of the intimal surface.

10 January 2026 in Diagnostics
Verified
Journal Article
Open access
PDF file
JSJIEN SAITO
JIEN SAITO
MMMasahiro Muto
Masahiro Muto
MTMasafumi Tada
Masafumi Tada
IYIsao Yokota
Isao Yokota
SKShinji Kamiya
Shinji Kamiya
SWSatoru Wakasa
Satoru Wakasa
Background/Objectives: This study examined the clinical utility of diffusion-weighted whole-body magnetic resonance imaging with background body signal suppression (DWIBS) for differentiating infectious from non-infectious aortitis. Methods: The study included 32 patients with suspected inflammatory aortitis who underwent non-contrast computed tomography (NCCT) and magnetic resonance imaging. We evaluated the diagnostic performance of DWIBS using the spinal cord as a reference, NCCT, and their combination. The diagnosis of infectious aortitis was adjudicated based on imaging, clinical, and laboratory findings. We conducted a sensitivity analysis using a stricter definition of infectious aortitis that required both surgical and microbiological confirmation. Results: Fifteen patients were diagnosed with infectious aortitis. The sensitivity, specificity, and areas under the receiver operating characteristic curves were 93.3%, 70.6%, and 0.82, respectively, for NCCT; 93.3%, 76.5%, and 0.85, respectively, for DWIBS; and 86.7%, 94.1%, and 0.90, respectively, for the combination of both modalities. In the sensitivity analysis, the combined DWIBS and NCCT approach demonstrated a specificity of 87.5% and a sensitivity of 70.8%. Conclusions: DWIBS using the spinal cord as a reference appears to be a promising diagnostic tool for differentiating infectious from non-infectious aortitis, especially when combined with NCCT.

1 January 2026 in Annals of Vascular Diseases
Verified
Journal Article
Open access
PDF file
JSJIEN SAITO
JIEN SAITO
SKShinji Kamiya
Shinji Kamiya
HSHideki Sasaki
Hideki Sasaki
Postsurgical thrombotic microangiopathy (TMA) is a highly lethal complication. We report a 71-year-old woman who developed TMA following open thoracoabdominal aortic aneurysm repair. From postoperative day 2, she presented with progressive thrombocytopenia, acute kidney injury, and hemolytic anemia. Therapeutic plasma exchange (PE) and hemodialysis were promptly initiated upon clinical suspicion, without waiting for ADAMTS13 results. In conclusion, we experienced a case of postsurgical TMA triggered by profound surgical stress, in which prompt initiation of PE was effective. The patient successfully recovered from the acute phase and has remained in remission for over 3 years.