Bone Marrow Biopsy Needle Type Affects Core Biopsy Specimen Length and Quality and Aspirate Hemodilution

Miniature Integrated 2.4 GHz Rectennas Using Novel Tunnel Diodes

This work presents the design, fabrication, and measured results of a fully integrated miniature rectenna using a novel tunnel diode known as the Asymmetrical Spacer Layer Tunnel (ASPAT). The term rectenna is an abbreviation for a rectifying antenna, a device with a rectifier and antenna coexisting as a single design. The ASPAT is the centrepiece of the rectifier used for its strong temperature independence, zero bias, and high dynamic range. The antenna is designed to be impedance matched with the rectifier, eliminating the need for a matching network and saving valuable real estate on the gallium arsenide (GaAs) substrate. The antenna is fully integrated with the rectifier on a single chip, thus enabling antenna miniaturisation due to the high dielectric constant of GaAs and spiral design. This miniaturisation enables the design to be fabricated economically on a GaAs substrate whilst being comparable in size to a 15-gauge needle, thus unlocking applications in medical implants. The design presented here has a total die size of 4 × 1.2 mm², with a maximum measured output voltage of 0.97 V and a 20 dBm single-tone 2.35 GHz signal transmitted 5 cm away from the rectenna.

A prospective survey on trephine biopsy of bone and bone marrow: an experience with 274 Indian patients' biopsies

Trephine bone marrow biopsy is an effective technique for diagnosing hematological malignancies in patients of different ages. During trephine biopsy, bone marrow cores are obtained for detailed morphological evaluation to look for any abnormality and arrive at a diagnosis. The primary goal of this work is to perform a survey on Indian patients of various ages for the trephine bone marrow biopsy process. In the present study, data related to 274 trephine biopsy samples from 300 patients were acquired at the Post Graduate Institute of Medical Education and Research (PGIMER) in Chandigarh, India. Pain was found to be the sole major procedure-related complication, and patients reported no/less pain in 41 BMB (14.96%) patients, moderate pain in 82 (29.92%) cases, and unbearable pain in 151 (55.1%) BMB cases. In addition, the patients were evaluated by the authors and hematologist as non-anxious for the procedure in 34 (12.4%), anxious in 92 (33.57%), and very/highly anxious in 148 (56%) cases. The bone texture of the patients significantly affected the needle bending, number of repetitions required, and size of the bone marrow sample. This demonstrates the need for improvement in the biopsy procedure. To this end, a survey was conducted to assess the numerous difficulties and diagnostic outcomes throughout the trephine biopsy process.

Microfluidic isolation of aptamers with affinity towards multiple myeloma monoclonal immunoglobulins

Multiple myeloma (MM) is a bone marrow cancer of resident plasma cells that affects 125,000 patients in the U.S. with about 30,000 new cases per year. Its signature is the clonal proliferation of a single plasma cell that secretes a patient specific monoclonal immunoglobulin (M-Ig). Targeting the M-Ig in patient serum could allow sensitive and noninvasive identification of minimal residual disease in multiple myeloma. Aptamers, which are single-stranded oligonucleotides with affinity and specificity to a target molecule, have recently been introduced as affinity reagents for recognition of MM M-Igs. Here we exploit microfluidic SELEX technology to enable rapid and efficient generation of aptamers against M-Ig proteins from MM patients. We first characterize the technology by isolating aptamers with affinity towards the monoclonal antibody rituximab as a model M-Ig and then apply the technology to isolating aptamers specifically targeting M-Igs obtained from serum samples of MM patients. We demonstrate that high-affinity DNA aptamers (KD < 50 nM) for M-Ig proteins from a patient sample could be isolated via microfluidic SELEX within approximately 12 h and using less than 100 micrograms of patient M-Ig. Such aptamers can potentially be used in personalized monitoring of minimal residual disease in MM patients.

Contemporary Challenges in Clinical Flow Cytometry: Small Samples, Big Data, Little Time

Background

Immunophenotypic analysis of cell populations by flow cytometry has an established role in primary diagnosis and disease monitoring of many hematologic diseases. A persistent problem in evaluation of specimens is suboptimal cell counts and low cell viability, which results in an undesirable rate of analysis failure. In addition, the increased amount of data generated in flow cytometry challenges existing data analysis and reporting paradigms.

Content

We describe current and emerging technological improvements in cell analysis that allow the clinical laboratory to perform multiparameter analysis of specimens, including those with low cell counts and other quality issues. These technologies include conventional multicolor flow cytometry and new high-dimensional technologies, such as spectral flow cytometry and mass cytometry that enable detection of over 40 antigens simultaneously. The advantages and disadvantages of each approach are discussed. We also describe new innovations in flow cytometry data analysis, including artificial intelligence-aided techniques.

Summary

Improvements in analytical technology, in tandem with innovations in data analysis, data storage, and reporting mechanisms, help to optimize the quality of clinical flow cytometry. These improvements are essential because of the expanding role of flow cytometry in patient care.

A Synoptic Reporting System to Monitor Bone Marrow Aspirate and Biopsy Quality

Objectives:

Bone marrow evaluation plays a critical role in the diagnosis, staging, and monitoring of many diseases. Although there are standardized guidelines for assessing bone marrow specimen quality, there is a lack of evidence-based tools to perform such assessments. The objective was to monitor bone marrow sample quality in real time by standardizing the basic components of a synoptic report and incorporating it into a bone marrow report template.

Materials and Methods:

A relational database of bone marrow quality parameters was developed and incorporated into our laboratory information system bone marrow report template, with data entry completed during specimen sign out. Data from multiple reports created within a date range were extracted by Structured Query Language query, and summarized in tabular form. Reports generated from these data were utilized in quality improvement efforts.

Results:

The synoptic reporting system was routinely used to record the quality of bone marrow specimens from adult patients. Data from 3189 bone marrow aspirates, 3302 biopsies, and 3183 biopsy touch imprints identified hemodilution as the principal issue affecting bone marrow aspirate quality, whereas aspiration artifact and fragmentation affected bone marrow biopsy quality.

Conclusions:

The bone marrow synoptic reporting process was easy to use, readily adaptable, and has proved a useful component of the overall quality assurance process to optimize bone marrow quality.

Comparative analysis of CT guided vertebral biopsy by a conventional bone biopsy needle versus bone biopsy needle with acquisition cradle

BACKGROUND

We aimed to compare the rate of diagnostically successful vertebral biopsies using conventional bone biopsy needles versus those performed with bone biopsy needles with an acquisition cradle.

METHODS

We retrospectively analyzed the data of patients who underwent CT-guided vertebral biopsy between December 2017 to December 2019 at our institute. From December 2017 to November 2018, the procedure was performed on 185 patients using an 11G conventional bone biopsy needle, Jamshidi needleTM "(group 1)". From December 2018 to December 2019, the procedure was performed on 242 patients using an 11G T-handle Jamshidi needle with an acquisition cradle "(group 2)". We reviewed their histopathological reports for both groups of patients to determine the rate of diagnostically successful biopsies. We also compared the crush artifact amongst the unsuccessful biopsy samples acquired by the two types of biopsy needles.

RESULTS

427 patients (270 male and 157 female patients; mean age, 46.4 years; age range, 25-67 years) who underwent CT-guided vertebral biopsy from December 2017 to December 2019 were included in our study. In group 1, diagnostic success was achieved in 136 out of 185 biopsies (73.5%); whereas in group 2, diagnostic success was achieved in 219 out of 242 biopsies (90.50%), p < 0.0001. Out of the diagnostically unsuccessful biopsies in Group 1, 36 out of 49 (73.5%) were due to crush artifact; whereas crush artifact accounted for only 3 out of 23 (13.0%) diagnostically unsuccessful biopsies in group 2, p < 0.0001. Other causes of unsuccessful biopsies (hemorrhagic contents or presence of normal osseous tissue and fibrin only) were statistically insignificant.

CONCLUSION

The use of a T-handle Jamshidi needle with an acquisition cradle appears beneficial compared to the conventional Jamshidi needle in terms of the significantly higher rate of diagnostic success and a lower rate of crush artifact.

Personalized immunoglobulin aptamers for detection of multiple myeloma minimal residual disease in serum

Multiple myeloma (MM) is a neoplasm of plasma cells that secrete patient specific monoclonal immunoglobulins. A recognized problem in MM treatment is the early recognition of minimal residual disease (MRD), the major cause of relapse. Current MRD detection methods (multiparameter flow cytometry and next generation sequencing) are based on the analysis of bone marrow plasma cells. Both methods cannot detect extramedullary disease and are unsuitable for serial measurements. We describe the methodology to generate high affinity DNA aptamers that are specific to a patient’s monoclonal Fab region. Such aptamers are 2000-fold more sensitive than immunofixation electrophoresis and enabled detection and quantification of MRD in serum when conventional MRD methods assessed complete remission. The aptamer isolation process that requires small volumes of serum is automatable, and Fab specific aptamers are adaptable to multiple diagnostic formats including point-of-care devices.

Tapia-Alveal, Olsen and Worgall develop a novel strategy for patient-specific multiple myeloma diagnostics platform using DNA aptamers. The high affinity DNA aptamers enabled detection of minimal residual disease (MRD) when conventional MRD methods assessed complete remission and are adaptable to multiple diagnostic formats including point-of-care devices.