Hiroshi Ohyama

653 total citations
58 papers, 378 citations indexed

About

Hiroshi Ohyama is a scholar working on Surgery, Oncology and Pulmonary and Respiratory Medicine. According to data from OpenAlex, Hiroshi Ohyama has authored 58 papers receiving a total of 378 indexed citations (citations by other indexed papers that have themselves been cited), including 40 papers in Surgery, 30 papers in Oncology and 28 papers in Pulmonary and Respiratory Medicine. Recurrent topics in Hiroshi Ohyama's work include Pancreatic and Hepatic Oncology Research (28 papers), Gallbladder and Bile Duct Disorders (22 papers) and Pediatric Hepatobiliary Diseases and Treatments (12 papers). Hiroshi Ohyama is often cited by papers focused on Pancreatic and Hepatic Oncology Research (28 papers), Gallbladder and Bile Duct Disorders (22 papers) and Pediatric Hepatobiliary Diseases and Treatments (12 papers). Hiroshi Ohyama collaborates with scholars based in Japan, United States and Germany. Hiroshi Ohyama's co-authors include Rintaro Mikata, Hitoshi Mochizuki, Masao Omata, Yosuke Hirotsu, Naoya Kato, Shin Yasui, Toshio Oyama, Kenji Amemiya, Harutoshi Sugiyama and Toshio Tsuyuguchi and has published in prestigious journals such as The Lancet, Cancer and Scientific Reports.

In The Last Decade

Hiroshi Ohyama

48 papers receiving 369 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Hiroshi Ohyama Japan 12 187 165 128 72 54 58 378
Akihito Nishio Japan 9 170 0.9× 134 0.8× 83 0.6× 40 0.6× 78 1.4× 18 376
Ewa Pomianowska Norway 12 214 1.1× 318 1.9× 82 0.6× 28 0.4× 38 0.7× 14 395
Chrysanthi Aggeli Greece 13 183 1.0× 124 0.8× 61 0.5× 87 1.2× 41 0.8× 27 381
Hajime Otsu Japan 14 261 1.4× 146 0.9× 247 1.9× 76 1.1× 155 2.9× 38 502
Yoichi Saitoh Japan 9 202 1.1× 156 0.9× 82 0.6× 37 0.5× 34 0.6× 14 334
Tsann-Long Hwang Taiwan 14 312 1.7× 272 1.6× 242 1.9× 71 1.0× 54 1.0× 18 516
Jiro Shimazaki Japan 13 289 1.5× 260 1.6× 134 1.0× 88 1.2× 227 4.2× 41 683
Shuichi Tsukamoto Japan 11 77 0.4× 132 0.8× 106 0.8× 48 0.7× 107 2.0× 23 333
Daniela Paccagnella Italy 8 110 0.6× 150 0.9× 81 0.6× 54 0.8× 84 1.6× 11 361

Countries citing papers authored by Hiroshi Ohyama

Since Specialization
Citations

This map shows the geographic impact of Hiroshi Ohyama's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Hiroshi Ohyama with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Hiroshi Ohyama more than expected).

Fields of papers citing papers by Hiroshi Ohyama

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Hiroshi Ohyama. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Hiroshi Ohyama. The network helps show where Hiroshi Ohyama may publish in the future.

Co-authorship network of co-authors of Hiroshi Ohyama

This figure shows the co-authorship network connecting the top 25 collaborators of Hiroshi Ohyama. A scholar is included among the top collaborators of Hiroshi Ohyama based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Hiroshi Ohyama. Hiroshi Ohyama is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Takahashi, Koji, Hiroshi Ohyama, Izumi Ohno, & Naoya Kato. (2025). Factors Affecting Patency of Uncovered Duodenal Stents in Malignant Duodenal Stenosis Due to Pancreatic Cancer: A Retrospective Cohort Study. Cureus. 17(1). e77245–e77245.
2.
Sakai, Yuji, Toshio Tsuyuguchi, Hiroshi Ohyama, et al.. (2024). Usefulness of Elobixibat in Patients With Chronic Constipation After Cholecystectomy. Cureus. 16(8). e67132–e67132. 1 indexed citations
3.
Ohyama, Hiroshi, Yosuke Hirotsu, Kenji Amemiya, et al.. (2024). Liquid biopsy of wash samples obtained via endoscopic ultrasound‐guided fine‐needle biopsy: Comparison with liquid biopsy of plasma in pancreatic cancer. Diagnostic Cytopathology. 52(6). 325–331. 1 indexed citations
4.
Ohyama, Hiroshi, Rintaro Mikata, Yosuke Hirotsu, et al.. (2024). The efficacy of bile liquid biopsy in the diagnosis and treatment of biliary tract cancer. Journal of Hepato-Biliary-Pancreatic Sciences. 31(5). 329–338. 4 indexed citations
5.
6.
Ohyama, Hiroshi, Yosuke Hirotsu, Kenji Amemiya, et al.. (2023). Comparison of genomic profiling of circulating tumor DNA in pancreaticobiliary malignancies in plasma and bile. Cancer. 129(11). 1714–1722. 4 indexed citations
7.
Takahashi, Koji, et al.. (2023). Endoscopic Transpapillary Stenting for Malignant Hilar Biliary Stricture: Side-by-Side Placement versus Partial Stent-in-Stent Placement. Journal of Personalized Medicine. 13(5). 831–831. 1 indexed citations
8.
Ohyama, Hiroshi, Yosuke Hirotsu, Kenji Amemiya, et al.. (2023). Development of a molecular barcode detection system for pancreaticobiliary malignancies and comparison with next-generation sequencing. Cancer Genetics. 280-281. 6–12. 18 indexed citations
9.
10.
Maeda, Takahiro, et al.. (2023). Addition of Mechanical Lithotripsy to Endoscopic Papillary Large Balloon Dilation in Patients with Difficult Common Bile Duct Stones: A Retrospective Single-Center Study. Journal of Laparoendoscopic & Advanced Surgical Techniques. 33(12). 1162–1166. 1 indexed citations
11.
12.
Ohyama, Hiroshi, Yosuke Hirotsu, Kenji Amemiya, et al.. (2022). Detection of actionable mutations in cytological specimens obtained by endoscopic ultrasound-guided fine needle aspiration with rapid onsite evaluation in pancreatic cancer. Annals of Diagnostic Pathology. 60. 152008–152008. 4 indexed citations
13.
Mikata, Rintaro, Tetsuhiro Chiba, Masayuki Yokoyama, et al.. (2021). Analysis of circulating cell-free DNA after endoscopic ultrasound-guided fine needle aspiration in pancreatic ductal adenocarcinoma. Pancreatology. 21(6). 1030–1037.
14.
Higuchi, Rumi, Taichiro Goto, Yosuke Hirotsu, et al.. (2021). Sphingomonas and Phenylobacterium as Major Microbiota in Thymic Epithelial Tumors. Journal of Personalized Medicine. 11(11). 1092–1092. 14 indexed citations
15.
16.
Ohyama, Hiroshi, Yosuke Hirotsu, Kenji Amemiya, et al.. (2021). Detection of actionable mutations in archived cytological bile specimens. Journal of Hepato-Biliary-Pancreatic Sciences. 28(10). 837–847. 8 indexed citations
17.
Hirotsu, Yosuke, Sotaro Otake, Hiroshi Ohyama, et al.. (2020). Dual-molecular barcode sequencing detects rare variants in tumor and cell free DNA in plasma. Scientific Reports. 10(1). 3391–3391. 26 indexed citations
18.
Hirotsu, Yosuke, Hitoshi Mochizuki, Kenji Amemiya, et al.. (2019). Deficiency of mismatch repair genes is less frequently observed in signet ring cell compared with non-signet ring cell gastric cancer. Medical Oncology. 36(3). 23–23. 12 indexed citations
19.
Hirotsu, Yosuke, Hiroshi Ohyama, Hitoshi Mochizuki, et al.. (2019). Molecular subtype switching in early-stage gastric cancers with multiple occurrences. Journal of Gastroenterology. 54(8). 674–686. 15 indexed citations
20.
Mikata, Rintaro, Takashi Kishimoto, Masahiro Hayashi, et al.. (2017). Immunohistochemical analysis of IMP3 and p53 expression in endoscopic ultrasound-guided fine needle aspiration and resected specimens of pancreatic diseases. Pancreatology. 18(2). 176–183. 22 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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