Contribution of real-time elastography in diagnosis of polycystic ovary syndrome

Diagnostic value of ultrasound elastography in polycystic ovary syndrome: a systematic review and meta-analysis

OBJECTIVE

The main purpose of this systematic review and meta-analysis was to investigate the diagnostic value of ultrasound elastography in the evaluation of polycystic ovary syndrome (PCOS).

METHODS

A comprehensive and methodical investigation was carried out in the databases of PubMed, EMBASE, Cochrane, Scopus, Web of Science, and China National Knowledge Infrastructure, covering the entire duration of these databases until October 18, 2023. The primary purpose of this research was to evaluate and contrast ovarian tissue elasticity in people with and without PCOS. The elasticity of ovarian tissue was quantified using standardized mean difference (SMD).

RESULTS

A total of eight studies were ultimately selected for systematic evaluation and meta-analysis. Five studies used shear wave elastography (SWE) as a diagnostic tool, and it was discovered that women with PCOS had higher levels of ovarian shear wave elasticity than their healthy counterparts. The SMD was determined to be 1.86 kilopascal (95% CI: 1.27 to 2.44). Three studies were conducted using strain elastography (SE) to compare the ovarian strain ratio of patients with PCOS to that of a healthy control group. The SMD for the PCOS group was 2.07 (95% CI: 1.79 to 2.34), which indicated that the ovarian strain ratio was significantly higher in that group.

CONCLUSION

This systematic review and meta-analysis found that women with PCOS had stiffer ovarian tissue than women without the disorder. Ultrasound elastography may provide clinicians with value beyond 2D ultrasound in the diagnosis of PCOS.

Ultrasonographic criteria in the diagnosis of polycystic ovary syndrome: a systematic review and diagnostic meta-analysis

BACKGROUND

Polycystic ovary morphology (PCOM) on ultrasonography is considered as a cardinal feature of polycystic ovarian syndrome (PCOS). Its relevance as a diagnostic criterion for PCOS was reaffirmed in the most recent International Evidence-Based Guideline for the Assessment and Management of PCOS. However, there remains a lack of clarity regarding the best practices and specific ultrasonographic markers to define PCOM.

OBJECTIVE AND RATIONALE

The aim of this systematic review and diagnostic meta-analysis was to assess the diagnostic accuracy of various ultrasonographic features of ovarian morphology in the diagnosis of PCOS.

SEARCH METHODS

Relevant studies published from 1 January 1990 to 12 June 2023 were identified by a systematic search in PubMed, Web of Science, Scopus, CINAHL, and CENTRAL. Studies that generated diagnostic accuracy measures (e.g. proposed thresholds, sensitivity, specificity) for PCOS using the following ultrasonographic markers met criteria for inclusion: follicle number per ovary (FNPO) or per single cross-section (FNPS), ovarian volume (OV), and stromal features. Studies on pregnant or post-menopausal women were excluded. Risk of bias and applicability assessment for diagnostic test accuracy studies were determined using the QUADAS-2 and QUADAS-C tool for a single index test or between multiple index tests, respectively. Diagnostic meta-analysis was conducted using a bivariate model of pooled sensitivity and specificity, and visualized using forest plots and summary receiver-operating characteristic (SROC) curves.

OUTCOMES

From a total of 2197 records initially identified, 31 studies were included. Data from five and two studies were excluded from the meta-analysis due to duplicate study populations or limited data for the index test, leaving 24 studies. Pooled results of 20 adult studies consisted of 3883 control participants and 3859 individuals with PCOS. FNPO was the most accurate diagnostic marker (sensitivity: 84%, CI: 81-87%; specificity: 91%, CI: 86-94%; AUC: 0.905) in adult women. OV and FNPS had similar pooled sensitivities (OV: 81%, CI: 76-86%; FNPS: 81%, CI: 70-89%) but inferior pooled specificities (OV: 81%, CI: 75-86%; FNPS: 83%, CI: 75-88%) and AUCs (OV: 0.856; FNPS: 0.870) compared to FNPO. Pooled results from four adolescent studies consisting of 210 control participants and 268 girls with PCOS suggested that OV may be a robust ultrasonographic marker for PCOS diagnosis albeit the current evidence remains limited. The majority of the studies had high risk of bias for the patient selection (e.g. lack of randomized/consecutive patient selection) and index test (e.g. lack of pre-proposed thresholds for comparison) domains across all ultrasonographic markers. As such, diagnostic meta-analysis was unable to determine the most accurate cutoff for ultrasonographic markers to diagnose PCOS. Subgroup analysis suggested that stratification based on previously proposed diagnostic thresholds, age, BMI, or technology did not account for the heterogeneity in diagnostic accuracy observed across the studies. Studies that diagnosed PCOS using the Rotterdam criteria had improved sensitivity for FNPO. Studies from North America had lower diagnostic accuracy when compared to Asian studies (FNPO: sensitivity) and European studies (OV: specificity, diagnostic odds ratio and positive likelihood ratio). Geographic differences in diagnostic accuracy may potentially be due to differences in age, BMI, and diagnostic criteria of the PCOS group across regions.

WIDER IMPLICATIONS

This diagnostic meta-analysis supports the use of FNPO as the gold standard in the ultrasonographic diagnosis of PCOS in adult women. OV and FNPS provide alternatives if total antral follicle counts cannot be accurately obtained. Our findings support the potential for ultrasonographic evidence of PCOM in adolescents as more data becomes available. Subgroup analysis suggests the need to investigate any relative contributions of geographical differences on PCOS phenotypes. These findings may provide the basis for the development of strategies and best practices toward a standardized definition of PCOM and a more accurate ultrasonographic evaluation of PCOS.

Evaluation of endometrial receptivity by ultrasound elastography to predict pregnancy outcome is a non-invasive and worthwhile method

Up to today, there is no effective, specific and non-invasive evaluation method to assess the endometrial receptivity. This study aimed to establish a non-invasive and effective model with the clinical indicators to evaluate endometrial receptivity. Ultrasound elastography can reflect the overall state of the endometrium. Ultrasonic elastography images from 78 hormonally prepared frozen embryo transfer (FET) patients were assessed in this study. Meanwhile, the clinical indicators reflecting endometrium in the transplantation cycle were collected. The patients were received to transfer only one high-quality blastocyst. A novel code rule that can generate a large number of 0-1 symbols was designed to collect data on different factors. At the same time, a logistic regression model of the machine learning process with an automatic combination of factors was designed for analysis. The logistic regression model was based on age, body mass index, waist-hip ratio, endometrial thickness, perfusion index (PI), resistance index (RI), elastic grade, elastic ratio cutoff value, serum estradiol level and 9 other indicators. The accuracy rate of predicting pregnancy outcome of the logistic regression model was 76.92%. Elastic ultrasound can reflect the endometrial receptivity of patients in FET cycles. We established a prediction model including ultrasound elastography and the model precisely predicted the pregnancy outcome. The predictive accuracy of endometrial receptivity by the predictive model is significantly higher than that of the single clinical indicator. The prediction model by integrating the clinical indicators to evaluate endometrial receptivity may be a non-invasive and worthwhile method for evaluating endometrial receptivity.

Ovarian Stiffness Is Significantly Increased in Polycystic Ovary Syndrome and Related With Anti-Mullerian Hormone: A Point Shear Wave Elastography Study

OBJECTIVES

Parenchymal stiffness obtained by point shear-wave elastography (pSWE) in solid organs is used as a sign of damage in these organs. However, its clinical use and whether patients with polycystic ovary syndrome (PCOS) have increased ovarian tissue stiffness are still unclear. The aim of this study is to determine the parameters related to ovarian stiffness and whether there is an increase in ovarian stiffness in patients with PCOS compared with healthy controls.

METHODS

Forty-five women who were followed up regularly with the diagnosis of PCOS and 30 healthy controls similar to age and sex were included in this study. In addition to the routine follow-up parameters for PCOS, serum homeostatic model assessment of insulin resistance and anti-Mullerian hormone (AMH) levels were examined in all patients, and pSWE examination was performed with pelvic ultrasound (US) and ElastPQ technique.

RESULTS

Serum dehydroepiandrosterone sulfate, luteinizing hormone/follicle-stimulating hormone, testosterone, homeostatic model assessment of insulin resistance, and AMH were higher in PCOS compared with healthy controls (P < 0.001). Right, left, and mean ovary stiffness and volumes were significantly higher in PCOS group than healthy controls (P < 0.001). Correlation analysis was performed between mean ovary stiffness and dehydroepiandrosterone sulfate, luteinizing hormone/follicle-stimulating hormone, testosterone, homeostatic model assessment, and AMH and ovary volumes (P < 0.01 for each one). In linear regression analysis, only AMH was found to be related to mean ovary stiffness (P < 0.001 and β = 0.734).

CONCLUSIONS

Ovarian stiffness value obtained by ElastPQ technique and pSWE method increases in PCOS patients compared with healthy controls and is closely related to serum AMH levels. In patients with PCOS, in addition to the conventional US, ovarian stiffness measured by pSWE may be an auxiliary examination in the follow-up of the disease. However, it was concluded that the ovarian stiffness measurement obtained in our current study should be supported by studies involving more patients and the transvaginal US method.

Diagnostic value of shear wave velocity in polycystic ovarian syndrome

Aim: In polycystic ovarian syndrome, the ovaries become stiffer due to chronic anovulation. We aimed to compare tissue elasticity in terms of shear wave velocities measured using acoustic radiation force impulse imaging technique between the ovaries of polycystic ovarian syndrome women and non-polycystic ovarian syndrome women. Material and methods: The study was designed as a retrospective data analysis of women who underwent transvaginal ultrasound and acoustic radiation force impulse imaging in a university hospital between July 2014 and March 2015, for various reasons. There were 32 polycystic ovarian syndrome patients and 32 patients without a diagnosis of polycystic ovarian syndrome. Age, body mass index, fasting glucose levels, cycle day 3 follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, prolactin, antimullerian hormone levels, and menstrual patterns with clinical hyperandrogenism were evaluated. On the menstrual cycle days 2-4, by performing a transvaginal ultrasound scan, the ovarian volumes and antral follicle counts in both ovaries were recorded for each woman. The ultrasound system was converted into the elastography mode, and acoustic radiation force impulse imaging was performed. Shear wave velocity (m/sec) was measured at least 5 times for each ovary, and the mean value was calculated for each polycystic ovarian syndrome and non-polycystic ovarian syndrome woman. Results: Age, body mass index, fasting glucose levels, cycle day 3 follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, and prolactin levels were similar between the groups (p >0,05). Antimullerian hormone levels, antral follicle counts, and mean ovarian volumes were statistically different between the groups (p <0,05). Mean shear wave velocity values for both ovaries were 2.12 ± 0.82 (0.78-4.9) m/sec in the polycystic ovarian syndrome group, and 1.18 ± 0.41 (0.77-2.0) m/sec in the non-polycystic ovarian syndrome group, which was statistically significantly different (p = 0.016). Conclusion: In our study, we found significantly higher shear wave velocity levels in polycystic ovarian syndrome women than non-polycystic ovarian syndrome women, which indicates an impact of the condition on shear wave velocity. The increased acoustic frequencies cause a decreased response in time to transition, and motion becomes out of phase; in other words, scattered waves are faster in stiffer ovaries. Our results are thus compatible with the pathophysiology of the disease. Shear wave velocity is a beneficial tool for evaluating ovarian elasticity in polycystic ovarian syndrome patients in whom the levels are found to be significantly higher than non-polycystic ovarian syndrome women. In light of these findings, shear wave velocity is expected to be slower than polycystic ovarian syndrome levels in ovulatory women.

Mechanobiology of the female reproductive system

BACKGROUND

Mechanobiology in the field of human female reproduction has been extremely challenging technically and ethically.

METHODS

The present review provides the current knowledge on mechanobiology of the female reproductive system. This review focuses on the early phases of reproduction from oocyte development to early embryonic development, with an emphasis on current progress.

MAIN FINDINGS RESULTS

Optimal, well-controlled mechanical cues are required for female reproductive system physiology. Many important questions remain unanswered; whether and how mechanical imbalances among the embryo, decidua, and uterine muscle contractions affect early human embryonic development, whether the biomechanical properties of oocytes/embryos are potential biomarkers for selecting high-quality oocytes/embryos, whether mechanical properties differ between the two major compartments of the ovary (cortex and medulla) in normally ovulating human ovaries, whether durotaxis is involved in several processes in addition to embryonic development. Progress in mechanobiology is dependent on development of technologies that enable precise physical measurements.

CONCLUSION

More studies are needed to understand the roles of forces and changes in the mechanical properties of female reproductive system physiology. Recent and future technological advancements in mechanobiology research will help us understand the role of mechanical forces in female reproductive system disorders/diseases.

Evaluation of Ovaries in Patients with Polycystic Ovary Syndrome using Shear Wave Elastography

BACKGROUND

Shear wave electrography (SWE) is a novel non-invasive imaging technique which demonstrate tissue elasticity. Recent research evaluating the elasticity properties of normal and pathological tissues emphasize the diagnostic importance of this technique.

AIMS

Polycystic ovarian syndrome (PCOS), which is characterized by menstrual irregularity, hyperandrogenism, and polycystic overgrowth, may cause infertility. The aim of this study was to evaluate the elasticity of ovaries in patients with PCOS using SWE.

METHODS

66 patients diagnosed with PCOS according to the Rotterdam criteria (PCOS = group I) and 72 patients with non-PCOS (Control = group II), were included in the study. Demographic and clinical characteristics of the participants were recorded. Ovarian elasticity was assessed in all patients with SWE, and speed values were obtained from the ovaries. The elasticity of the ovaries was compared between the two groups.

RESULTS

While there were statistically significant differences between the groups in body mass index (BMI), right and left ovarian volumes, luteinizing hormone and testosterone levels (p<0.05), no significant differences were found between groups I and II in the velocity (for the right ovary 3.89±1.81 vs. 2.93±0.72, p=0.301; for the left ovary 2.88±0.65 vs. 2.95±0.80, p=0.577) and elastography (for the right ovary 36.62±17.78 vs. 36.79±14.32, p=0.3952; for the left ovary 36.56±14.15 vs. 36.26±15.10, p=0.903) values, respectively.

CONCLUSION

We could not obtain different velocity and elastography values from the ovaries of the patients with PCOS using SWE. Therefore, further large-scale studies are needed to elucidate this issue.

Role of shear wave elastography in predicting the metabolic and androgenic alterations in patients with polycystic ovary syndrome

AIM

To evaluate the variation in tissue stiffness caused by the changes in ovarian volume and stroma in polycystic ovary syndrome (PCOS) using a novel method of ultrasonography, that is shear wave elastography (SWE). The current study also aimed to evaluate the potential applications of this method in predicting the metabolic and androgenic alterations in patients with PCOS.

METHODS

The present study included 33 patients with PCOS. The blood samples for the metabolic and androgenic parameters and SWE values pertaining to the patients were obtained on the same day during the early follicular phase. The predictive ability of SWE to reflect the metabolic and androgenic abnormalities was evaluated using the receiver operating characteristic curve (ROC) analysis.

RESULTS

The mean SWE value pertaining to the group with higher total testosterone levels was significantly lower, compared to the group with normal testosterone levels (p = 0.041). The ROC analysis revealed that the predictive potential of SWE was statistically significant in regard to the serum testosterone levels alone (area under the curve [AUC] = 0.755, 95% confidence interval [CI]: 0.573-0.938, p = 0.041). There was no significant relationship between the SWE values and metabolic parameters.

CONCLUSIONS

Based on the results of the present study, decreased SWE values appear to be associated with increased serum testosterone levels. However, the present study did not observe any significant relationship between the SWE values and metabolic parameters. SWE can be used as a practical and non-invasive method to predict the serum testosterone levels during the follow-up evaluations of the patients with PCOS.

Differentiation Between Phenotypes of Polycystic Ovarian Syndrome With Sonography

Objectives:

To differentiate between the classic (A/B) from the nonclassic (C/D) phenotypes of the polycystic ovarian syndrome (PCOS) with sonography.

Materials & Methods:

Retrospective analysis was performed upon 72 female patients with PCOS. All patients underwent transvaginal sonography. The patients were classified into classic and nonclassic phenotypes of PCOS. Image analysis was performed for the ovarian volume, follicle counts, follicle size, and endometrial plate thickness.

Results:

There were significant differences in the ovarian volume ( P = .001), follicle counts ( P = .001), follicle size ( P = .001), and endometrial plate thickness ( P = .001) between classic and nonclassic phenotypes of PCOS. The threshold value for ovarian volume, follicle count, follicle size, and endometrial plate thickness used to differentiate classic from nonclassic phenotypes were 12.5, 10.5, 5.25, and 5.75, respectively, with an area under the curve of 0.79, 0.82, 0.83, 0.77 and an accuracy of 75%, 73.6%, 79.2%, and 68.1%, respectively. The serum testosterone level and the body mass index were significantly higher in patients with classic than nonclassic phenotypes of PCOS ( P = .001, .04), respectively.

Conclusion:

Sonography findings can differentiate classic from nonclassic phenotypes of PCOS.

Evaluation of the medial rectus muscle and optic nerve using strain and shear wave elastography in Graves' patients

PURPOSE

The purpose of this study was to describe the elastic properties of the medial rectus muscle and optic nerve in Graves' patients without clinically apparent ophthalmopathy using strain elastography (SE) and shear wave elastography (SWE) and to determine whether these elastic properties could be used to aid in the diagnosis of the medial rectus muscle or optic nerve involvement.

MATERIALS AND METHODS

Thirty participants diagnosed with Graves' disease without ophthalmopathy and 30 healthy volunteers (control group) were prospectively examined between November 2018 and August 2019. SE and SWE findings in both groups were compared using the χ² test and the independent samples t test.

RESULTS

A statistically significant softening of the medial rectus muscle was observed in the SE patterns of the Graves' patients (p = 0.009). A statistically appreciable distinction was observed between the medial rectus muscle (7.64 ± 2.1 and 9.20 ± 1.7 kPa, p = 0.000) and the optic nerve (8.35 ± 2.8 and 9.37 ± 1.5 kPa, p = 0.019) in the SWE modulus of the Graves' patients and healthy volunteers.

CONCLUSION

SE and SWE can be used to identify structural alterations to the medial rectus muscle and optic nerve before clinically apparent Graves' ophthalmopathy has developed.

Ultrasound Shear Wave Velocity Varies Across Anatomical Region in Ex Vivo Bovine Ovaries

The physical properties of the ovarian extracellular matrix (ECM) regulate the function of ovarian cells, specifically the ability of the ovary to maintain a quiescent primordial follicle pool while allowing a subset of follicles to grow and mature in the estrous cycle. Design of a long-term, cycling artificial ovary has been hindered by the limited information regarding the mechanical properties of the ovary. In particular, differences in the mechanical properties of the two ovarian compartments, the cortex and medulla, have never been quantified. Shear wave (SW) ultrasound elastography is an imaging modality that enables assessment of material properties, such as the mechanical properties, based on the velocity of SWs, and visualization of internal anatomy, when coupled with B-mode ultrasound. We used SW ultrasound elastography to assess whole, ex vivo bovine ovaries. We demonstrated, for the first time, a difference in mechanical properties, as inferred from SW velocity, between the cortex and medulla, as measured along the length (cortex: 2.57 ± 0.53 m/s, medulla: 2.87 ± 0.77 m/s, p < 0.0001) and width (cortex: 2.99 ± 0.81 m/s, medulla: 3.24 ± 0.97 m/s, p < 0.05) and that the spatial distribution and magnitude of SW velocity vary between these two anatomical planes. This work contributes to a larger body of literature assessing the mechanical properties of the ovary and related cells and specialized ECMs and will enable the rational design of biomimetic tissue engineered models and durable bioprostheses. Impact Statement Shear wave (SW) ultrasound elastography can be used to simultaneously assess the material properties and tissue structures when accompanied with B-mode ultrasound. We report a quantitative difference in mechanical properties, as inferred from SW velocity, between the cortex and medulla, with SW velocity being 11.4% and 8.4% higher in the medulla than the cortex when measured along the length and width, respectively. This investigation into the spatial and temporal variation in SW velocity in bovine ovaries will encourage and improve design of more biomimetic scaffolds for ovarian tissue engineering.

Evaluation of the Optic Nerve by Strain and Shear Wave Elastography in Patients With Migraine

OBJECTIVES

To investigate the optic nerve's elastic properties using shear wave and strain elastography in patients with migraine compared to healthy individuals.

METHODS

The migraine group consisted of 30 patients (16 with visual auras and 14 without auras) who had previously had a diagnosis of migraine. These were age and sex matched with healthy participants to form the control group. The findings from shear wave and strain elastography in the groups were compared. The elastographic examination was performed with a 6-15-MHz multifrequency linear array transducer.

RESULTS

The evaluation involved 30 patients with migraine (3 male and 27 female), whose mean age ± SD was 34.63 ± 10 years, and 30 healthy participants (3 males, 27 females), whose mean age was 36.4 ± 10.5 years. In strain elasticity patterns, a statistically insignificant hardening of the optic nerve in the patients with migraine was observed (P = .052). Analysis of the shear wave elastic modulus values (9.8 ± 3.34 and 12.3 ± 5.25 kPa; P = .03) revealed that differences between the healthy participants and patients with migraine were statistically significant. The results for elasticity patterns and the shear modulus suggested that the differences between migraines with and without visual auras were insignificant (P > .05). A positive correlation was discovered between the duration of the disease and the shear modulus in the patients with migraine (r = 0.496; P < .01).

CONCLUSIONS

Histopathologic changes in the optic nerve may be seen in patients with migraine due to possible fibrotic changes. Elastographic techniques can be useful diagnostic tools for investigating these changes.

Sonoelastographic evaluation of the sciatic nerve in patients with unilateral lumbar disc herniation

OBJECTIVE

The aim of this study was to compare strain elastography (SE) and shear wave elastography (SWE) findings of the sciatic nerve in patients with unilateral lumbar disc herniation (LDH) and healthy control subjects.

MATERIALS AND METHODS

The study group included patients with complaints of unilateral sciatica for 3-12 months, with foraminal stenosis due to one level of LDH (L4-L5 or L5-S1). An age- and gender-matched control group was formed of healthy subjects. Evaluations were performed on both the axial and longitudinal planes from the bilateral gluteal region using a 5-9 MHz multifrequency convex probe.

RESULTS

There were 40 patients (20 male, 20 female) with a mean age of 43.1 ± 12.7 years in the study group, and 40 healthy subjects (22 male, 18 female) with a mean age of 42.9 ± 10.7 years in the control group (p > 0.05). The sciatic nerve stiffness assessed on both the axial (12.3 ± 3.7 kPA) and longitudinal (14.3 ± 3.8 kPA) planes of the involved side was significantly higher than non-involved side (axial: 6.8 ± 2.1 and longitudinal: 8.3 ± 2.3 kPA) in the patient group (p < 0.001).

CONCLUSIONS

Patients with unilateral LDH have increased stiffness of the sciatic nerve compared to healthy control subjects. Although the findings in this preliminary study show that shear wave elastography can detect a change in sciatic nerve stiffness in patients with unilateral LDH, larger studies are required to determine the clinical utility of this technique.

Is real-time elastography helpful to differentiate acute from subacute deep venous thrombosis? A preliminary study

PURPOSE

To detect and characterize changes in stiffness of thrombus in patients with acute and subacute deep venous thrombosis (DVT) by using real-time elastography (RTE).

METHODS

Fifty-eight patients with acute or subacute DVT were prospectively evaluated by B-mode sonography (US), color Doppler US (CDUS), and RTE. Two radiologists evaluated the thrombus echogenicity, compressibility, and recanalization of the affected vein, and thrombus stiffness in consensus. The thrombi were classified into 3 groups as soft, intermediate, and hard on RTE images.

RESULTS

The final study group consisted of 30 patients with acute DVT, among whom 10 were women (33%), and 19 patients with subacute DVT, among whom 6 were women (32%). The presence of hypoechoic thrombus, incompressible vein, and absence of recanalization on US and CDUS were significantly associated with acute DVT (P < .001 for all variables). The differences in elasticity pattern of the thrombi between acute and subacute DVT were not significant (P = .202).

CONCLUSION

Venous thrombus hardens with age; however, elastography pattern on RTE, in its present form, may not be able to differentiate acute DVT from subacute DVT.

Evaluation of Optic Nerve with Strain and Shear Wave Elastography in Patients with Behçet's Disease and Healthy Subjects

The objective of this study was to investigate the elasticity characteristics of the optic nerve using strain and shear wave elastography in patients with Behçet's disease and to compare the results with those of healthy volunteers. Forty-six optic nerves from patients with Behçet's disease and 54 optic nerves from healthy volunteers were investigated prospectively in this study using strain and shear wave elastography. There was a statistically significant difference in terms of elasticity patterns between patients and healthy volunteers (p < 0.001). Elastographic images of healthy volunteers revealed most optic nerves to be type 3 (51.8%); however, type 2 (40.7%) and type 1 (7.5%) were also observed. Elastographic examination of Behçet's disease patients revealed type 2 in 52.2%, type 1 in 43.5% and type 3 in 4.3% of patients. Statistically significant differences were observed between patients and healthy volunteers in the analysis of shear wave elastography values (p < 0.001). Receiver operating characteristic curve analysis was perfect (0.933) (95% CI = 0.885-0.980), and a cutoff value of 16.5 kPa shear had very high sensitivity and specificity for the patient group. Strain and shear wave elastography findings for the optic nerves of patients with Behçet's disease were significantly different from those for healthy volunteers.

Usefulness of transabdominal real-time sonoelastography in the evaluation of ovarian lesions: preliminary results

OBJECTIVE

We aim to evaluate and describe the tissue elasticity characteristics of various ovarian lesions with sonoelastography.

METHODS

35 patients (age range 16-85 years; mean age 40.8 years) underwent sonoelastography and later MRI. Histopathological confirmation of all lesions was carried out, except eight of endometriomas and six of septated cysts which were confirmed on MRI and follow-up ultrasonography. Strain ratios and elastogram patterns were recorded. Lesions were classified into three groups (Group 1: cystic lesions, Group 2: benign tumours and Group 3: malignant lesions) and findings were compared between groups for both observers. Interobserver agreement was analyzed. Optimal cut-off values for strain ratios were achieved with receiver operating characteristic curve analysis.

RESULTS

Ovarian endometriomas and complex cystic lesions were observed hard on elastograms with high strain ratios, and malignant lesions were observed mostly soft with very small strain ratios. Benign tumours had average tissue stiffness, observed harder than the malignant lesions, and strain ratios ranged from 4 to 14. The differences in patterns and strain ratios between groups were statistically significant (p < 0.05 for both observers).

CONCLUSION

Our study revealed that malignant ovarian lesions have softer tissue property than benign lesions and cystic lesions in terms of elastogram patterns and strain ratios.

ADVANCES IN KNOWLEDGE

Most ovarian lesions contain solid and cystic parts which make the malignant and benign lesions look similar on imaging modalities. Using real-time sonoelastography as an adjunct to other imaging modalities may improve the differentiation of malignant ovarian lesions from benign lesions.