Liver biopsy is the gold‑standard method for diagnosing liver diseases, assessing the degree of liver fibrosis and guiding therapeutic decisions. Among various biopsy needles, the Menghini liver biopsy needle has been widely used worldwide for more than half a century since its invention in 1958 by Italian pathologist Giorgio Menghini, thanks to its distinctive design, efficient operation and reliable safety profile. Its technological evolution represents a history of innovation transitioning from classic manual aspiration to deep integration with modern imaging technologies.

The Classic Menghini Needle: Core Principles and Design Essence

The core design philosophy of the Menghini needle lies in speed, safety and minimal invasiveness. Essentially a negative‑pressure aspiration biopsy needle, its classic structure consists of a sharp‑beveled tip, a hollow cannula, a removable stylet (to seal the needle lumen during puncture and prevent entry of non‑target tissue), and a connector for attaching a syringe to generate negative pressure.

Its operating principle is ingenious and efficient. Under ultrasound or CT guidance, the needle tip is rapidly punctured through the liver capsule. The syringe plunger is then quickly withdrawn to create strong instantaneous negative pressure, which draws liver tissue into the cannula lumen while the sharp edge of the needle tip cuts the tissue. The biopsy needle is rapidly removed while maintaining negative pressure, yielding an intact cylindrical strip of liver tissue. The entire procedure is typically completed within 1–2 seconds.

The advantages of this design are evident:

Rapid operation: A single puncture retrieves sufficient specimens, shortening the needle's dwell time inside the body.

Relatively minimal trauma: As it relies on aspiration rather than cutting, it theoretically causes less parenchymal laceration than cutting‑type biopsy needles, potentially lowering bleeding risks.

High‑quality specimens: The obtained tissue strips are usually intact and continuous, suitable for histopathological examination including evaluation of hepatic lobular architecture, inflammatory grading and fibrosis staging.

Technical Comparison: Menghini Needle vs. Tru‑Cut Needle

To understand the status of the Menghini needle, it must be compared with another mainstream type: the Tru‑Cut needle (or cutting‑type biopsy needle). The Tru‑Cut needle comprises an outer cannula with a sharp tip and an inner stylet featuring a notch at the front. During operation, the inner stylet is advanced first to lodge tissue into the notch, followed by rapid advancement of the outer cannula to cut the tissue within the notch.

The key differences between the two are as follows:

• Sampling mechanism: The Menghini needle depends on negative‑pressure aspiration; the Tru‑Cut needle relies on mechanical cutting.
• Specimen characteristics: Tissue strips obtained by the Menghini needle are thinner and longer, sometimes slightly deformed by negative pressure; those from the Tru‑Cut needle are thicker and shorter with more well‑preserved structure, especially suitable for livers with hard texture or severe fibrosis.
• Operational difficulty and risks: Traditionally, the Menghini needle is deemed simpler and faster to operate with a slightly lower bleeding risk. The Tru‑Cut needle requires a two‑step procedure with a steeper learning curve, demanding higher operator control and greater caution in patients with poor coagulation function.

Modern Modifications and Evolution

Classic Menghini needles were mostly reusable stainless‑steel devices requiring rigorous cleaning and sterilization. With improved medical safety standards and widespread use of single‑use consumables, modern Menghini needles have evolved into single‑use sterile products. Manufacturers have introduced numerous optimizations based on the classic design:

• Needle tip design: Optimized bevel angle and sharpness to reduce puncture resistance and tissue injury.
• Material upgrades: Adoption of higher‑grade medical‑grade stainless steel to ensure rigidity and biocompatibility. Titanium alloys are used in some high‑end products for enhanced MRI compatibility.
• Diversified specifications: Needles of varying lengths (typically 15–20 cm) and gauges (e.g., 16G, 18G) are available to accommodate patients of different body types and clinical needs (e.g., finer 18G needles for pediatric use).
• Integration and user‑friendliness: Many modern products feature pre‑attached or integrated syringes/negative‑pressure devices to simplify procedures and improve standardization.

Technological Competition Among Manufacturers

Numerous medical device companies worldwide produce Menghini‑style liver biopsy needles. Beyond traditional European and American brands, Chinese manufacturers represented by Manners Technology are emerging with robust precision manufacturing capabilities. Manufacturers such as Manners Technology offer not only standard‑specification products but also customized services, adjusting parameters including needle length, diameter and tip morphology to meet specific requirements of hospitals or research institutions. Such flexibility is vital for conducting special clinical research or managing complex cases.

Furthermore, some manufacturers have combined Menghini needles with automatic firing devices to develop semi‑automatic biopsy guns. These devices standardize and accelerate puncture and aspiration actions, further reducing complication risks caused by variations in operator technique, and are particularly suitable for novice practitioners.

Conclusion

From the original prototype by Giorgio Menghini to today's highly standardized and safe single‑use medical devices, the evolution of the Menghini liver biopsy needle embodies the eternal rule that clinical needs drive technological innovation. Although emerging non‑invasive diagnostic technologies (e.g., transient elastography) can replace biopsy in certain scenarios, histopathological examination remains irreplaceable for definitive diagnosis, assessment of active inflammation and guidance of precision therapy. Featuring classic design, high efficiency and reliability, the Menghini needle still holds an unshakable vital position in the diagnostic armamentarium of hepatology. In the future, with advances in materials science and minimally invasive technologies, it will continue to evolve toward greater safety, precision and intelligence.