A bibliometric analysis of Cushing’s disease and magnetic resonance imaging: history, research hotspots, and emerging trends

Introduction

Cushing’s disease, caused by adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma, is the most common cause of endogenous Cushing’s syndrome, accounting for approximately 70% of cases (1-3). Pituitary adenomas are the most prevalent tumors in the sellar region. Approximately 10% of the general population has pituitary adenomas detectable by imaging or autopsy. Among different kinds of pituitary adenomas, ACTH-secreting adenomas account for around 4%, with a significantly higher incidence in females than males (8:1) (4). Cushing’s disease affects multiple systems throughout the body, including the cardiovascular system, metabolic system, immune system, skeletal system, and nervous system (2). Typical clinical features include moon face, buffalo hump, purple striae, central obesity, hypertension, impaired glucose tolerance, menstrual irregularity, and osteoporosis (Figure 1) (5).

Figure 1 Cushing’s disease can affect multiple body systems, and magnetic resonance imaging is the most powerful diagnostic tool. CBF, cerebral blood flow; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging.

In 2021, the International Pituitary Society emphasized the challenge of the diagnosis of Cushing’s disease. The diagnosis was often delayed by several years due to a lack of awareness of the disease (2,6), and Cushing’s disease was difficult to distinguish from other causes of Cushing’s syndrome. Preoperative diagnosis of Cushing’s disease primarily relies on a comprehensive analysis of clinical symptoms, signs, laboratory tests, and pituitary magnetic resonance imaging (MRI). Laboratory tests focus on cortisol and ACTH levels, including assessments of diurnal rhythm, dexamethasone suppression tests, bilateral inferior petrosal sinus sampling (BIPSS), and desmopressin stimulation tests. Treatment for Cushing’s disease mainly includes surgery, medical therapy, and radiotherapy. Transsphenoidal surgery is recommended as the first-line treatment, performed by experienced surgeons, with remission observed in approximately 80% of patients with microadenomas and 60% with macroadenomas, and overall low surgical complication rates. Medical therapy and radiotherapy are primarily used for persistent or recurrent Cushing’s disease and for patients with hypercortisolism who are unsuitable for or refuse surgery (2,7-10).

In 1990, Carsin et al. utilized MRI to scan nine patients with Cushing’s disease, demonstrating that MRI was the most sensitive and specific method for diagnosing ACTH-secreting pituitary adenomas (11). Subsequently, in 1993, Escourolle et al. and Buchfelder et al. conducted both computed tomography (CT) and MRI scans on patients with Cushing’s disease, concluding that MRI was superior to CT in detecting pituitary lesions (12,13). With advancements in MRI technology, the use of higher field strengths and additional MRI sequences has further increased the sensitivity of MRI in the diagnosis of Cushing’s disease. International consensus recommended MRI as the preferred imaging modality for detecting ACTH-secreting pituitary adenomas, with 3.0 T MRI favored over 1.5 T MRI for better diagnostic accuracy. Moreover, recent developments in advanced imaging sequences, such as 3-dimensional (3D) gradient echo and 3D-enhanced fluid-attenuated inversion recovery (FLAIR), have shown potential in improving the visualization of small pituitary lesions, particularly in cases with equivocal or negative findings on conventional imaging. These sequences offer higher spatial resolution and superior contrast between adenomas and surrounding tissues, thus increasing the likelihood of detecting microadenomas. Incorporating these novel techniques into standard imaging protocols may further enhance the diagnostic performance of MRI in patients with Cushing’s disease (14-16). A combination of functional MRI might eventually surpass conventional MRI alone (2). In addition to its critical role in the diagnosis of Cushing’s disease, MRI has been considered essential for predicting postoperative remission. Studies have shown that the preoperative size of the pituitary adenoma, the presence of cavernous sinus invasion, and tumor visibility were essential indicators for predicting postoperative remission in patients with Cushing’s disease (17). For ACTH-secreting pituitary adenomas that were difficult to operate on, MRI-based neuronavigation has significantly aided in the surgical treatment of patients with Cushing’s disease (18).

Bibliometric analysis is the quantitative study of publications, mainly focusing on the publication landscape description, publication performance of important authors and affiliations, citation life of important publications, research hotspots, and emerging trends. The concept of bibliometric analysis dates back to 1969, when it was defined as the quantitative analysis of recorded discourse (19,20). With time, apart from various quantitative tools used for the statistical analysis of publication and citation numbers, there has been huge progress in computational methods and software for text processing and clustering analysis to visualize research hotspots and emerging trends, making bibliometrics a powerful tool for providing the landscape of a specific research field as well as detecting its evolution and frontiers.

Bibliometric analysis has been applied in many medical fields, and its value has been widely recognized (21). In the field of Cushing’s disease and the application of MRI in its diagnosis, treatment, and prognosis, there has been no such review to indicate the research focuses and the emerging trends. To fill this gap, this study aimed to perform a bibliographic review on Cushing’s disease and MRI technology to map the research landscape and detect the emerging research trends. We present this article in accordance with the BIBLIO reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-221/rc).

Methods

Search strategies

The study focused on the publications about Cushing’s disease and MRI technology. The data were retrieved from the Science Citation Index Expanded (SCI-EXPANDED) database of the Clarivate Analytics Web of Science Core Collection (WoSCC). Key search words about Cushing’s disease included “Cushing disease”, “Cushing’s disease”, “Cushing diseases”, and “Cushing’s diseases”. Key search words about MRI included “MRI” and “magnetic resonance imaging”. As a result, the search strategies was set as: (TS=(“Cushing disease”) OR TS=(“Cushing’s disease”) OR TS=(“Cushing diseases”) OR TS=(“Cushing’s diseases”)) AND (TS=(“MRI”) OR TS=(“magnetic resonance imaging”)). The search was performed in the Topic field within the publication year limitation from 1991 to 2023 (22). The retrieval was manually checked for their relevance. Finally, 587 publications were defined as topic-related documents. Their full record including publication information and citation history was downloaded. Among all the documents, only articles in English underwent further analysis.

Key bibliometric indicators

To investigate the citation history of the publications, we introduced four citation indicators:

• C_year: the number of citations from WoSCC in a particular year. In this study, we used the indicator C₂₀₂₃, meaning the number of citations of an article in 2023;
• TC_year: the total number of citations from WoSCC from the publication year to a particular year. In this study, we used the indicator TC₂₀₂₃, meaning the number of citations of an article since its publication to the year 2023;
• TP: the total number of citations from WoSCC of a particular group of articles;
• CPP_year: citations per publication, CPP_year = TC_year/TP. In this study, we used the indicator CPP₂₀₂₃.

Analytical methods and tools

To begin with, authors, their affiliations, and nationalities were analyzed. The first author and the corresponding author are regarded as the two most important authors for a publication, so the top productive first authors and corresponding authors were collected. The top productive affiliations and the collaborative relationship between different affiliations were identified. Furthermore, the top productive countries and their bibliometric information were gathered. In the analysis of countries, affiliations from England, Scotland, Northern Ireland, and Wales were classified as from the United Kingdom (UK). Affiliations from mainland China and from Taiwan were classified as from China.

VOSviewer is a powerful tool for the visualization of co-authorship and co-occurrence analysis (23). Here, VOSviewer was used to visualize the co-authorship between affiliations with time-overlaying features and the co-occurrence among author keywords in clusters.

CiteSpace is another visualization software for co-citation analysis (24). It supports cluster generation and cluster naming using various sources including keywords, references, authors, affiliations, and so on. In this study, CiteSpace was used for reference co-citation analysis and cluster generation using the embedded algorithm.

The workflow of this study is shown in Figure 2.

Figure 2 The workflow of this study. WoSCC, Web of Science Core Collection.

Results

Document types

The total of 555 English-language documents (94.5% of 587 documents) could be classified into seven document types in WoSCC, including 464 articles (83.6%), 66 reviews (11.9%), 10 meeting abstracts (1.8%), 7 letters (1.3%), 5 editorial material (0.9%), 2 notes (0.4%), and 1 correction (0.2%) (Table 1). Each article has an average of 7.0 authors and 26.2 times of citation. Reviews are another important topic for a medical topic—they usually make up a small percentage of the overall documents but have significant higher average citation numbers then articles. However, in this study, topic-related reviews only had a slightly higher CPP₂₀₂₃ than articles.

The publication history of topic-related articles

Only the 464 English-language articles underwent further analysis. The distribution of annual publication number of articles and their average citation numbers are shown in Figure 3. There were two rapid growths: the annual number of articles increased from 12 in 2011 to 26 in 2015, and the annual number of articles increased from 14 in 2018 to 30 to reach a peak in 2021. With the increase of annual publication number, the citation number per article decreased.

Figure 3 Number of topic-related articles and citations per publication by year.

Journals and Web of Science categories

A total of 464 English-language articles were published in 142 journals. The top 10 productive journals are listed in Table 2. Journal of Clinical Endocrinology & Metabolism (IF₂₀₂₃ =5.0) and Clinical Endocrinology (IF₂₀₂₃ =3.0) published the most articles (TP =34), followed by Endocrine Journal (IF₂₀₂₃ =1.3, TP =26), European Journal of Endocrinology (IF₂₀₂₃ =5.3, TP =24), and Pituitary (IF₂₀₂₃ =3.3, TP =22). Of note, Journal of Clinical Endocrinology & Metabolism not only published the most articles, but had the highest CPP₂₀₂₃ of 55.8, meaning that its topic-related articles had an average of 55.8 times of citation. Articles in European Journal of Endocrinology (IF₂₀₂₃ =5.3) and Neurosurgery (IF₂₀₂₃ =3.9) were also of high quality, with CPP₂₀₂₃ of 54.8 and 53.1, respectively.

Most of the top productive journals fell into the category of Endocrinology and Metabolism (7/10), and the others fell into the category of Clinical Neurology and Surgery (3/10). An alluvial diagram was used to detect the dynamic evolution of categories of journals that accepted research papers on Cushing’s disease and MRI with time. Over the past 3 decades, categories of journals that accepted topic-related articles have become increasingly more diverse, expanding from 8 to 12, which reflected the multidisciplinary nature of this topic (Figure 4). In each of the 5-year time frames, surgery and pediatrics were the consistent discipline categories. During 2014–2018, in particular, surgery and psychiatry became the top 2 predominant categories, due to the advance in surgical technologies and the emergence of new research hotspots. Radiology, nuclear medicine and medical imaging and neuroscience were another two major research fields that constantly drew research attention. In the recent 5 years [2019–2023], healthcare services and nutrition emerged as new research categories, indicating a focus on the healthcare and nutrition management of patients with Cushing’s disease. In general, research on Cushing’s disease and MRI showed its multidisciplinary nature from the early times and had evolved to encompass a wider range of disciplines.

Figure 4 The evolution of journal categories shown in an alluvial diagram.

Publication performance: authors, institutions, and countries

The first author and the corresponding author (reprint author) are the most important authors for a publication. The top 3 productive first authors were Hong Jiang from China (TP =6), Ulrich J Knappe from Germany (TP =4), and Márcio Carlos Machado from Brazil (TP =4). The top 3 productive corresponding authors were Edward H. Oldfield from USA (TP =7), Prashant Chittiboina from USA (TP =6), and Qing-Fang Sun from China (TP =6).

The publication performance of institutions worldwide is shown in Figure 5, wherein each circle represents an institution. The larger the circle, the higher the publication number. Lines between the circles represent the collaboration between institutions. The top productive institutions included National Institutes of Health (NIH), National Institute of Neurological Disorders & Stroke (NINDS), National Institute of Child Health & Human Development (NICHD), University of Virginia, Mayo Clinic, Chinese Academy of Medical Sciences & Peking Union Medical College (PUMC), and Shanghai Jiao Tong University. This time-overlaying figure also shows the peak publication time of each institution. Circles in yellow indicate institutions that published topic-related articles around 2020, whereas circles in dark indicate institutions that publish in the early times. As a result, the recent top productive institutions included PUMC, Harvard Medical School, Chinese People’s Liberation Army General Hosp, Tehran University of Medical Sciences, and Postgraduate Institute of Medical Education and Research.

Figure 5 The time overlay visualization of the publication performance and collaboration network of institutions.

The top 15 productive countries and their publication performance are shown in Table 3. USA ranked top in 5 bibliometric indictors including a TP of 131, an IP of 107, a CP of 24, an FP of 118, and an RP of 124, showing its domination in this field. China ranked the second in 4 indictors including TP, IP, FP, and RP. Japan ranked the third in the above 4 indictors. UK, USA, and the Netherlands were the top 3 countries that published high-quality articles with CPP₂₀₂₃ of 41.6, 41.4, and 37.6, respectively.

Citation history of the 10 most cited articles since 1991 and the most cited articles in 2023

The citation history of the 10 most cited articles from 1991 to 2023 is shown in Figure 6. Half of the top 10 articles were published in the 1990s, having a longer impact history, but most of them were less influential in recent years. An article by Hall et al. that performed MRI on normal volunteers to detect occult adenomas was the most cited article with a TC₂₀₂₃ of 422 (rank 1), and it was still highly cited with a C₂₀₂₃ of 14 (rank 3) (25). The citation history of the 11 most cited articles in 2023 was shown in Figure 7. Besides the aforementioned study by Hall et al., all the other articles were published after 2005. An article by McEwen on sleep deprivation was the most cited article in 2023 with a C₂₀₂₃ of 17, and it was the second most cited article since 1991. A total of 3 articles published in the recent 5 years appeared in the list of most cited articles in 2023; these included the study by Frete et al. about the non-invasive diagnostic strategy of Cushing’s disease (26), the study by Chen et al. about the optimal cut-off of BIPSS in diagnosis of ACTH-dependent Cushing’s syndrome (27), and the study by Berkmann et al. about the selective resection of Cushing microadenoma guided by preoperative positron emission tomography (PET)/MRI (28).

Figure 6 The citation history of top 10 highly cited articles since 1991. TC₂₀₂₃, the number of citations of an article since its publication to the year 2023.

Figure 7 The citation history of top 11 highly cited articles in 2023. C₂₀₂₃, the number of citations of an article in 2023; TC₂₀₂₃, the number of citations of an article since its publication to the year 2023.

Research hotspots and emerging trends

The co-citation analysis of references is shown in Figure 8, with the cluster names generated by the log-likelihood ratio (LLR) algorithm based on article titles. Clusters in cold colors indicated topics that previously attracted research interests, whereas clusters in warm colors indicated topics that received attention in the recent decade. Based on the clustering results, the primary research themes were “Clinical value” (#7) and “Dependent Cushing’s syndrome” (#9). Research on “Diagnostic feature” (#1), “Diagnostic evaluation” (#4), and “Clinical characteristics” (#12) was mainly concentrated between 1990 and 2010. Current research hotspots were “Surgical remission” (#0), “Transsphenoidal surgery” (#5), “White matter integrity” (#8), and “Cognitive deficit” (#10).

Figure 8 The co-citation analysis of references.

The cluster analysis of author keywords in three time periods (1991–2001, 2002–2012, and 2013–2023) is separately shown in Figure 9, highlighting the evolution of new research focus with time. During 1991–2001, research primarily concentrated on the diagnosis and surgical treatment of Cushing’s disease. Keywords in the green area, such as “hormone”, “corticotropin”, and “secretion”, indicated studies on endocrine function and hormone therapy. The yellow area included keywords such as “radiotherapy” and “radiation”, indicating research on radiosurgery. In the 2002–2012 period, the number of keywords significantly increased with higher density connections. Cluster analysis showed the same focus on surgical methods, diagnostic techniques, and imaging studies. Notably, keywords such as “transsphenoidal surgery”, “bilateral adrenalectomy”, and “radiosurgery” suggested exploration of various treatment approaches. In the most recent decade, the clustering results showed an increasingly complex research network, indicating extensive research on the diagnosis, management, and treatment of Cushing’s disease. Emerging keywords included “long-term remission”, “microadenomas”, and “quality-of-life”, indicating new focus areas on long-term prognosis, microadenomas, and quality of life. A new cluster in the bottom, marked “New cluster”, contained keywords such as “brain”, “atrophy”, “depression”, and “volume”, highlighting recent research on brain structural changes and cognitive function impacts as emerging research hotspots.

Figure 9 The co-occurrence analysis of keywords.

Discussion

The invention of MRI in the 1970s significantly advanced medical imaging, enriching diagnostic methods and enhancing the accuracy and safety of disease diagnosis. Cushing’s disease, a primary cause of endogenous hypercortisolism, affects multiple body systems and severely influences patient quality of life. However, Cushing’s disease often presents insidiously, making diagnosis challenging. In 1984, Older et al. proposed the use of MRI in the diagnosis of Cushing’s disease (29). With the development of MRI technology, it has been widely applied in the evaluations of Cushing’s disease. In this study, we retrieved publications from the WoSCC and screened 464 English articles on MRI and Cushing’s disease from 1991 to 2023.

W.A. Hall from the US is the most influential researcher in this field due to his groundbreaking work in 1994. He conducted MRI scans with gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) injections on 100 volunteers, discovering that 10% of normal adults exhibited pituitary abnormalities. In patients with Cushing’s disease, the detection of analogous lesions on MRI scans demonstrated a positive predictive value of 86% (25). In the same year, Magiakou et al. highlighted the critical role of MRI in diagnosis of pediatric Cushing’s syndrome (30). The application of MRI in Cushing’s disease extends beyond diagnosis and follow-up. Starkman et al. explored the non-diagnostic uses of MRI, focusing on detecting the structural and neuropsychological changes in the brain due to endogenous hypercortisolism. In 1999, Starkman et al. used MRI to scan the brains of 22 Cushing’s disease patients before and after surgery, discovering that hippocampal atrophy was partially reversible post-treatment (31). In 2003, this team not only measured hippocampal volume in patients before and after treatment using MRI but also conducted neuropsychological tests, demonstrating that increases in hippocampal volume post-treatment were accompanied by improvements in neuropsychological function (32).

Co-citation and keyword analyses revealed the developmental trajectory and recent research hotspots in the field of MRI studies on Cushing’s disease. Cluster 1 (red area in Figure 7) focused on “diagnostic feature” (#1), “diagnostic evaluation” (#4), “clinical value” (#7), and “clinical characteristics” (#12) (Figure 6), emphasizing the role of MRI in diagnosis of Cushing’s disease. Diagnosing Cushing’s disease often took several years, primarily due to a lack of awareness regarding the disease progression. For a patient suspected of having Cushing’s syndrome, there was no single preferred laboratory test for diagnosis, nor was there a consensus on the timing and selection of tests (2,6). International consensus strongly recommended individualized decisions regarding the timing and choice of diagnostic tests based on the patient’s clinical situation. If Cushing’s syndrome was suspected, it is strongly recommended to start with tests such as urinary free cortisol, late-night salivary cortisol, dexamethasone suppression test, or a combination of these tests (2,33). After diagnosing Cushing’s syndrome, morning plasma ACTH levels should be measured to distinguish between ACTH-dependent and ACTH-independent causes of hypercortisolism. Using inferior petrosal sinus sampling to measure ACTH levels in the pituitary and peripheral veins was the gold standard for excluding ectopic ACTH secretion (2,4,34,35). MRI should be utilized when ACTH-dependent Cushing’s syndrome is clinically suspected. MRI was the preferred method for detecting ACTH-secreting pituitary adenomas. Consensus recommended using 3 T MRI instead of 1.5 T MRI to improve the detection of pituitary adenomas. Combining functional MRI with standard MRI might be a more effective approach than using MRI alone (2,36). BIPSS remains the gold standard for differentiating pituitary from ectopic ACTH secretion and should be considered when the diagnosis is uncertain (2).

There remained a small subset of microadenomas that are challenging to detect. Cluster 2 (brown area in Figure 7) primarily focused on the research involving PET in Cushing’s disease and MRI. PET has been explored as an alternative or adjunct to MRI for localizing ACTH-secreting adenomas (2). Early studies utilized ¹⁸F-fluoro-deoxy-glucose (¹⁸F-FDG) for detecting pituitary adenomas, but FDG uptake in the pituitary gland was shown to be dependent on endocrine function. Recent research has shifted towards using amino acid analogs such as ¹¹C-methionine (¹¹C-MET), ¹⁸F-fluoroethyl-L-tyrosine (¹⁸F-FET), and ⁶⁸Ga-corticotropin-releasing hormone as suitable radiotracers (14,28,36-38). Compared to ¹⁸F-FDG, methionine (MET)-PET had relatively lower uptake in surrounding brain tissue, whereas most types of pituitary adenomas exhibit increased ¹¹C-MET uptake. Recent studies report that 3.0 T MRI achieves a sensitivity of approximately 60–90% for detecting ACTH-secreting microadenomas, with improved visualization using advanced sequences (37,39,40). In comparison, MET-PET combined with MRI has shown even higher sensitivity in some studies, reaching up to 90% in cases with negative or equivocal conventional MRI findings (28,37,38). Combined registration with 3.0 T MRI provided higher accuracy in intrasellar localization of adenomas (14,37,38,40).

Cluster 3 (red area in Figure 7) focused on the application of MRI in “following transsphenoidal surgery (TSS)” (#5) for Cushing’s disease and in the postoperative assessment of “surgical remission” (#0) (Figure 6). The first-line treatment for Cushing’s disease is TSS (2), with the ideal outcome being high cortisol remission. However, even at renowned medical institutions with experienced neurosurgeons, not all patients achieved the desired postoperative results. In experienced pituitary centers, the current remission rate for surgery was 65–85% (41). Patients who did not achieve remission remain at risk for chronic cortisol excess. Therefore, identifying the predictors of remission following TSS was a key focus in managing Cushing’s disease patients. Various tests and examinations have been suggested as candidate predictors of remission (41,42). MRI has represented a crucial tool for assessing the feasibility of complete resection of pituitary adenomas. Previous studies have shown higher remission rates in patients with microadenoma (43-45), although some research has suggested that remission rates were similar regardless of tumor size (46). Factors determining postoperative remission were more related to the presence of invasive growth rather than tumor size (42,47,48). The visibility of the adenoma on preoperative MRI was another predictor of postoperative remission in Cushing’s disease (17,49). Studies have shown that patients with pituitary adenomas smaller than 3 mm have lower remission rates, possibly due to the difficulty in detecting and completely resecting (42). The visibility of the adenoma largely depended on MRI technology; using sensitive MRI techniques could improve detection rates and potentially lead to better outcomes (39,50). Additionally, some researchers have constructed machine learning models using MRI images and clinical data to predict postoperative remission in Cushing’s disease (51).

The new cluster in Figure 7 focused on “white matter integrity” (#8) and “cognitive deficits” (#10) (Figure 6), highlighting emerging research hotspots in Cushing’s disease and MRI studies in recent years. The neurocognitive and psychiatric symptoms of Cushing’s disease were first described by Starkman et al. in 1981, highlighting memory impairment and attention difficulties in patients (52). Since then, various neurocognitive changes in Cushing’s disease have been widely reported, including anxiety, sleep disturbances, fatigue, cognitive impairment, and, less commonly, manic behavior. The primary psychiatric symptoms were affective disorders, particularly depression and anxiety (53-58). The main cause of these psychiatric and neurocognitive deficits were the elevated endogenous cortisol levels affecting the brain. The harmful effects of high glucocorticoids on the human brain were mainly mediated by glucocorticoid receptors, which were widely distributed throughout the brain (31,32,59,60). Although surgery could immediately reverse hypercortisolemia, previous studies have shown that these psychiatric and neurocognitive changes are not entirely reversible even after biochemical remission (31,32,61,62). Recent research indicated that these symptoms in Cushing’s disease were related to structural and functional changes in the brain. MRI studies have found significant changes in brain volume in patients with Cushing’s disease (63). With advances in MRI techniques, studies have distinguished gray from white matter in the brains of Cushing’s disease patients. Research showed gray matter reductions in cortex, hippocampus, and cerebellum, further confirming brain atrophy in these patients (64-67). Research on white matter in Cushing’s disease was relatively limited. van der Werff et al. and Pires et al. described white matter abnormalities in patients with Cushing’s disease using diffusion tensor imaging (DTI), indicating loss of white matter integrity (68,69). Jiang et al. and Cui et al. used a practical various MRI techniques including DTI, diffusional kurtosis imaging, and neurite orientation dispersion and density imaging to study white matter changes in Cushing’s disease patients (70,71). In addition to structural abnormalities, functional networks in the brains of Cushing’s disease patients were also affected (57,72). Task-based functional MRI studies have shown decreased activation of the several cortexes in patients compared to healthy controls when processing of emotional faces (73). Resting-state functional MRI studies in Cushing’s disease patients indicated that three major functional networks are affected: the limbic network, the default mode network, and the executive control network (74). These changes partially explained the manifestation of psychiatric symptoms and cognitive impairments in Cushing’s disease patients. Although brain MRI research in Cushing’s disease has become more sophisticated, further studies are needed to better elucidate the mechanisms underlying these neuropsychiatric symptoms and cognitive deficits.

The study is not without limitations. Firstly, this study analyzed English articles from the single source of WoSCC. Articles from other databases that were not covered in WoSCC were missed from this study. Secondly, recently published high-quality studies might not have received due attention due to citation delays, and this should be addressed in future research. Thirdly, in this study, the article quality was evaluated by citation numbers. However, high citation numbers did not necessarily equal high quality. The citation number could be affected by various factors, including publication time, self-citation, and citations from the same group or affiliation.

Conclusions

Cushing’s disease and MRI technology are tightly linked, and MRI has had increasingly applied in the diagnosis, surgery, and quality of life assessment of patients with Cushing’s disease. Recent research hotspots included surgical remission, surgical modality, and brain structural and functional change. Emerging research trends included long-term remission, patient quality-of-life, and changes in brain structure and cognitive function.

Acknowledgments

We would like to express our gratitude to Professor Yuh-Shan Ho for his guidance.

Footnote

Reporting Checklist: The authors have completed the BIBLIO reporting checklist. Available at https://qims.amegroups.com/article/view/10.21037/qims-2025-221/rc

Funding: This work was supported by the Teaching Reform Project of Peking Union Medical College (No. 2022zlgc0120 to M.F.), Peking Union Medical College Hospital Research Funding for Postdoc (No. kyfyjj202403 to Y.C.), (Peking Union Medical College Hospital) National High-Level Hospital Clinical Research Funding (No. 2022-PUMCH-C-012 to M.F.), and CAMS Innovation Fund for Medical Sciences (No. 2023-I2M-C&T-B-008 to M.F.).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-221/coif). M.F. reports funding from the Teaching Reform Project of Peking Union Medical College (No. 2022zlgc0120), (Peking Union Medical College Hospital) National High-Level Hospital Clinical Research Funding (No. 2022-PUMCH-C-012), and CAMS Innovation Fund for Medical Sciences (No. 2023-I2M-C&T-B-008). Y.C. reports funding from Peking Union Medical College Hospital Research Funding for Postdoc (No. kyfyjj202403). The other authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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