Ultrasonic Needles for Bone Biopsy

Bone biopsy is an invasive clinical procedure, where a bone sample is recovered for analysis during the diagnosis of a medical condition. When the architecture of the bone tissue is required to be preserved, a core-needle biopsy is taken. Although this procedure is performed while the patient is under local anaesthesia, the patient can still experience significant discomfort. Additionally, large haematoma can be induced in the soft tissue surrounding the biopsy site due to the large axial and rotational forces, which are applied through the needle to penetrate bone. It is well documented that power ultrasonic surgical devices offer the advantages of low cutting force, high accuracy, and preservation of soft tissues. This paper reports a study of the design, analysis, and test of two novel power ultrasonic needles for bone biopsy that operate using different configurations to penetrate bone. The first utilizes micrometric vibrations generated at the distil tip of a full-wavelength resonant ultrasonic device, while the second utilizes an ultrasonic-sonic approach, where vibrational energy generated by a resonant ultrasonic horn is transferred to a needle via the chaotic motion of a free-mass. It is shown that the dynamic behavior of the devices identified through experimental techniques closely match the behavior calculated through numerical and finite-element analysis methods, demonstrating that they are effective design tools for these devices. Both devices were able to recover trabecular bone from the metaphysis of an ovine femur, and the biopsy samples were found to be comparable to a sample extracted using a conventional biopsy needle. Furthermore, the resonant needle device was also able to extract a cortical bone sample from the central diaphysis, which is the strongest part of the bone, and the biopsy was found to be superior to the sample recovered by a conventional bone biopsy needle.

[Bone marrow biopsy: processing and use of molecular techniques]

The rapid technological development in diagnostic pathology, especially of immunohistochemical and molecular techniques, also has a significant impact on diagnostic procedures for the evaluation of bone marrow trephine biopsies. The necessity for optimal morphology, combined with preservation of tissue antigens and nucleic acids on one hand and the wish for short turnaround times on the other hand require careful planning of the workflow for fixation, decalcification and embedding of trephines. Although any kind of bone marrow processing has its advantages and disadvantages, formalin fixation followed by EDTA decalcification can be considered a good compromise, which does not restrict the use of molecular techniques. Although the majority of molecular studies in haematological neoplasms are routinely performed on bone marrow aspirates or peripheral blood cells, there are certain indications, in which molecular studies such as clonality determination or detection of specific mutations need to be performed on the trephine biopsy. Especially, the determination of B- or T-cell clonality for the diagnosis of lymphoid malignancies requires stringent quality controls and knowledge of technical pitfalls. In this review, we discuss technical aspects of bone marrow biopsy processing and the application of diagnostic molecular techniques.

How I diagnose and treat splenic lymphomas

The incidental finding of an isolated splenomegaly during clinical assessment of patients evaluated for unrelated causes has become increasingly frequent because of the widespread use of imaging. Therefore, the challenging approach to the differential diagnosis of spleen disorders has emerged as a rather common issue of clinical practice. A true diagnostic dilemma hides in distinguishing pathologic conditions primarily involving the spleen from those in which splenomegaly presents as an epiphenomenon of hepatic or systemic diseases. Among the causes of isolated splenomegaly, lymphoid malignancies account for a relevant, yet probably underestimated, number of cases. Splenic lymphomas constitute a wide and heterogeneous array of diseases, whose clinical behavior spans from indolent to highly aggressive. Such a clinical heterogeneity is paralleled by the high degree of biologic variation in the lymphoid populations from which they originate. Nevertheless, the presenting clinical, laboratory, and pathologic features of these diseases often display significant overlaps. In this manuscript, we present our approach to the diagnosis and treatment of these rare lymphomas, whose complexity has been so far determined by the lack of prospectively validated prognostic systems, treatment strategies, and response criteria.