Diagnostic confirmation of cancer in solid organs is based on biopsy findings. In a standard 12-core prostate biopsy protocol, conventional biopsy needles sample only 0.95% (∼0.228 cm³) of a typical 24-cm³ prostate gland. The primary objective of this study was to enhance the sensitivity of standard biopsy protocol by gauging electrical properties of tissue simultaneously with tissue extraction for histopathology analysis. A conventional biopsy (Bx) needle was instrumented with an electrical impedance spectroscopy (EIS) sensor to interrogate the tissue volume surrounding the needle tip. The EIS-Bx device was evaluated in a series of saline bath and ex vivo porcine experiments. It was found to sense a volume of 0.286 cm³ of tissue around the needle tip. EIS measurements were recorded from three ex vivo human prostates using the device, and the extracted biopsy cores were histologically assessed. Prostate conductivity σ ranged from 0.179 to 0.3310 S/m for benign tissues and 0.0746 to 0.0837 S/m for malignant tissues at frequencies ranging from 1 to 100 kHz. Relative permittivity ϵ(r) ranged from 2.10×10⁶ to 2.9 × 10⁴ for benign and 6.63×10⁵ to 5.3 × 10³ for cancer tissues over the same frequency range. Both are found to be significantly higher in normal prostate tissues than in malignant tissue (p< 0.00001).

Significant electrical property differences noted between benign and malignant prostate tissues suggest the potential efficacy an EIS-Bx device would provide for cancer detection in a clinical setting. By sensing a greater fraction of the prostate's volume in real-time, the EIS-Bx device has the potential to improve the accuracy of cancer grading and volume estimation made with current biopsy procedures.

Currently biopsy is considered the gold standard for diagnosis of prostate cancer in humans, although it samples only 19mm 3 volume of prostate, corresponding to 0.95% of a 50cm 3 prostate gland for a regular 12-core biopsy procedure. The aim of this study was to increase the sampling volume by incorporating electrical impedance spectroscopy (EIS) into the standard biopsy needle. Electrical impedance can act as a reliable biomarker for distinguishing malignant from benign tissues in human prostate. The EIS biopsy needle allows tip of the needle to act as sensor to measure the electrical impedance of the tissue core extracted. The sensitivity of the prototype device was evaluated in a series of saline bath experiments. We demonstrated that EIS biopsy needle senses 286.92 mm 3 of volume of the tissue on either side of the needle trajectory for each core, adding up to 2 X 12 X 286.92 = 6886.08 mm 3 or 13.8% of tissue's volume. Thus, measuring electrical properties in addition to core extraction is expected to enhance the sensitivity and specificity of the device. A few experiments have been conducted on ex vivo porcine samples to envisage EIS biopsy needle's ability in distinguishing two different kinds of tissues.

Abstract-Electrical impedance was recorded at 21 discrete frequencies (1 to 100 kHz) from 27 ex vivo human prostates. These electrical properties were measured by using custom designed Electrical Impedance Spectroscopy (EIS) sensing biopsy (Bx) needles. EIS-Bx needles gauge the electrical properties of tissue in tandem with the tissue extraction (used for histopathological assessment). The EIS-Bx probe has a signal-tonoise ratio (SNR) of 65 dB across the frequency range (1 kHz to 100 kHz [7]. These contrasts are due to morphological differences present in the different prostatic tissue types. We have developed an electrical impedance spectroscopy (EIS) sensing biopsy (Bx) needle to record bipolar impedance measurements in tandem with tissue core extraction. We have demonstrated that this type of data has the potential to distinguish normal from abnormal tissue across a larger fraction of prostate volume than that sampled during conventional biopsy procedure [8] [9]. We present our most recent analysis of a 27 patient cohort evaluating how well these electrical properties discriminate cancer from non-cancer tissues in the prostate. II. EIS-BX DEVICE OVERVIEWDevice Design A typical biopsy needle is constructed of stainless steel and consists of an inner trocar and an outer cannula. BARD Maxcore Disposable Biopsy Instruments (MC1820, C.R. Bard, Murray Hill, NJ) extract a 22 mm long tissue core and are the standard biopsy needles used for prostate biopsy at our institution. These needles are modified into an EIS-Bx device by electrically isolating the two (inner and outer) needle elements; a thin insulating tube (polyimide) is adhered onto the surface of each of these elements, leaving just the tip of both needles exposed. The tips of inner and outer elements act as two electrodes, through which EIS based bipolar measurements are recoded. The two electrodes are interfaced to an impedance analyzer (HP4284A, Agilent Technologies) through a RCA plug and assembly of coaxial cables. A small current (<1mA) is applied between the tip electrodes. The impedance recorded is the ratio of induced voltage to the applied

In the present investigation, the genetic structure of four populations of Catla catla, sequences of mitochondrial gene, cytochrome b (cyto b) from four populations were sequenced and analyzed. The sequences of mitochondrial regions revealed high haplotype diversity and low nucleotide diversity. The lowest 249 polymorphic sites and 0.00 parsimony informative sites were detected in populations of Fish Federation Pond (CCFFB) whereas highest 330 polymorphic sites and 56 parsimony informative sites were detected in populations of Narmada River (CCNRH) in the cyto b gene sequences in Catla catla populations. The twelve different haplotypes were detected among the four populations studied, lowest population specific haplotype as 2.00 was observed in Fish Federation Pond (CCFFB) and highest was in Population of Narmada River and Tighra reservoir. Sequencing of cyto b gene revealed 12 number of haplotypes (h) with haplotype (gene) diversity (Hd) 0.8736 and nucleotide diversity (π) 0.6474. These data clearly indicated that, feral/wild population showing highest values of polymorphisms, parsimony, haplotype diversity showing good, healthy habitat is lotic water (Narmada River) and lentic water body (Tighra reservoir). The results also concluded that the partial cyto b is polymorphic and can be a potential marker to determine ecological habitat based genetic differentiation among the populations.