Pseudo-Meigs syndrome caused by a rapidly enlarging hydropic leiomyoma with elevated CA125 levels mimicking ovarian malignancy: a case report and literature review.

Pseudo-Meigs syndrome is a rare syndrome characterized by hydrothorax and ascites associated with pelvic masses, and patients occasionally present with elevated serum cancer antigen-125 (CA125) levels. Hydropic leiomyoma (HLM) is an uncommon subtype of uterine leiomyoma characterized by hydropic degeneration and secondary cystic changes. Rapidly enlarging HLMs accompanied by hydrothorax, ascites, and elevated CA125 levels may be misdiagnosed as malignant tumors. Here, we report a case of HLM in a 45-year-old Chinese woman who presented with ascites and hydrothorax. Preoperative abdominopelvic CT revealed a giant solid mass in the fundus uteri measuring 20 × 15 × 12 cm. Her serum CA125 level was elevated to 247.7 U/ml, while her hydrothorax CA125 level was 304.60 U/ml. The patient was initially diagnosed with uterine malignancy and underwent total abdominal hysterectomy and adhesiolysis. Pathological examination confirmed the presence of a uterine hydropic leiomyoma with cystic changes. After tumor removal, the ascites and hydrothorax subsided quickly, with no evidence of recurrence. The patient's serum CA125 level decreased to 116.90 U/mL on Day 7 and 5.6 U/mL on Day 40 postsurgery. Follow-up data were obtained at 6 months, 1 year, and 2 years after surgery, and no recurrence of ascites or hydrothorax was observed. This case highlights the importance of accurate diagnosis and appropriate management of HLM to achieve successful outcomes.

Design, analysis and control of a novel tendon-driven magnetic resonance-guided robotic system for minimally invasive breast surgery.

Biopsy and brachytherapy for small core breast cancer are always difficult medical problems in the field of cancer treatment. This research mainly develops a magnetic resonance imaging-guided high-precision robotic system for breast puncture treatment. First, a 5-degree-of-freedom tendon-based surgical robotic system is introduced in detail. What follows are the kinematic analysis and dynamical modeling of the robotic system, where a mathematic dynamic model is established using the Lagrange method and a lumped parameter tendon model is used to identify the nonlinear gain of the tendon-sheath transmission system. Based on the dynamical models, an adaptive proportional-integral-derivative controller with friction compensation is proposed for accurate position control. Through simulations using different sinusoidal input signals, we observe that the sinusoidal tracking error at 1/2π Hz is 0.41 mm. Finally, the experiments on tendon-sheath transmission and needle insertion performance are conducted, which show that the insertion precision is 0.68 mm in laboratory environment.

Modelling and control of a five-degrees-of-freedom pneumatically actuated magnetic resonance-compatible robot.

BACKGROUND: Magnetic resonance imaging (MRI) combined with robotic assistance has the potential to improve on clinical outcomes of biopsy and local treatment of prostate cancer. This paper introduces a pneumatically actuated surgical robotic system for prostatic interventions under MRI guidance. METHODS: A mechanical dynamics model was established using the Lagrange method and simulated using MATLAB software. A pneumatic actuator model was built through the use of system identification, and stability analysis was proposed based on the Nyquist criterion. In addition, a proportional-integral-derivative controller was implemented on the robot for accurate position control. RESULTS: Simulation results showed that the steady-state error of a step response was 0.3 mm and the tracking error of a 1.0 Hz sinusoidal response was 1.5 mm. Experimental results showed that the insertion precision was 0.72 mm in the general laboratory environment. CONCLUSIONS: The results demonstrated that the robotic system with the designed controller was effective in both position control and trajectory tracking.