Conventional Tissue Processing Research Articles

EVALUATION OF THE EFFICACY OF VARIOUS XYLENE SUBSTITUTES AS A CLEARING AGENT IN TISSUE PROCESSING: A COMPARATIVE STUDY

Conventional tissue processing is still remains the gold standard. Tissue processing is a physical process that involves chemical solutions reacting with biological specimens. The main purpose of tissue processing is to embed the tissue in solid medium, firm enough to support the tissue and give it sufficient rigidity to enable thin sections to be cut and soft enough not to damage the knife or tissue. For any tissue specimen to undergo diagnosis, it has to follow procedural steps such as fixation, dehydration, clearing, impregnation, embedding, sectioning and staining. Clearing is the process of replacing the dehydrating solution (which is not miscible with the embedding medium) with a substance which will be miscible with alcohol and the embedding medium. The most commonly used clearing agent is xylene. It has excellent clearing capabilities. But it cause unwelcome effects on the various system of the human body like on skin, eyes, nervous system, blood, liver and kidneys as reported by Kandyala et al. In the present study, we evaluate the efficacy of three materials like Kerosene, Turpentine and Olive oil other than xylene which are substitutes as a clearing agent in tissue processing and observe their effect on staining characteristics and compare with xylene. It is better promoting to eliminate xylene from the histology laboratory is a duty of those who are in decision-making positions. Since our study was limited in sample size and there are very less studies comparing all the four chemicals in clearing agent, it is recommended to carry this study in large scale with addition of different substitutes and analyzing with multiple observers.

MP43-02 COMBINATION OF MICROSCOPIC TESTICULAR SPERM EXTRACTION (MTESE) AND DENSITY GRADIENT PROCESSING TO OPTIMIZE SPERM RETRIEVAL AND PREGNANCY OUTCOMES IN MEN WITH NONOBSTRUCTIVE AZOOSPERMIA (NOA)

You have accessJournal of UrologyCME1 Apr 2023MP43-02 COMBINATION OF MICROSCOPIC TESTICULAR SPERM EXTRACTION (MTESE) AND DENSITY GRADIENT PROCESSING TO OPTIMIZE SPERM RETRIEVAL AND PREGNANCY OUTCOMES IN MEN WITH NONOBSTRUCTIVE AZOOSPERMIA (NOA) Nicholas Deebel, Banafsheh Nikmehr, Janmejay Hingu, Collette O'Connor, Rachel Ruble, Yueqiang Song, Ayse Vuruskan, Anuradha Devineni, Cihan Halicigil, Stuart Howards, Tamer Yalcinkaya, and Hooman Sadri-Ardekani Nicholas DeebelNicholas Deebel More articles by this author , Banafsheh NikmehrBanafsheh Nikmehr More articles by this author , Janmejay HinguJanmejay Hingu More articles by this author , Collette O'ConnorCollette O'Connor More articles by this author , Rachel RubleRachel Ruble More articles by this author , Yueqiang SongYueqiang Song More articles by this author , Ayse VuruskanAyse Vuruskan More articles by this author , Anuradha DevineniAnuradha Devineni More articles by this author , Cihan HalicigilCihan Halicigil More articles by this author , Stuart HowardsStuart Howards More articles by this author , Tamer YalcinkayaTamer Yalcinkaya More articles by this author , and Hooman Sadri-ArdekaniHooman Sadri-Ardekani More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003289.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: mTESE with Intracytoplasmic sperm injection (ICSI) is the gold standard for treating infertile couples when NOA in the male is present. However, using conventional tissue processing techniques, many patients will remain negative for sperm on mTESE. Standard practice in assisted reproduction technology (ART) does not utilize the density gradient centrifugation process following mTESE. We hypothesize that gradient utilization can enrich sperm retrieval following mTESE. METHODS: Men with NOA underwent mTESE from 2019-2022 by a single surgeon. The biopsy specimens underwent mechanical dissection. Subsequent tissue processing and gradient wash were carried out through a gradient column including 90% and 50% gradient solution diluted in standard sperm wash medium. Upon verification of sperm, the post-gradient sperm and remaining un-dissociated tissue were cryopreserved separately. On the day of ICSI, the frozen gradient sperm were thawed to recover viable sperm. If needed, frozen tissue was thawed, subjected to mechanical dissociation, and a subsequent gradient to obtain enough viable sperm. Fertilization and embryo development were assessed morphologically with the Embryoscope and genetically with preimplantation genetic testing for aneuploidy (PGT-A). Following embryo transfer, biochemical (ß-HCG) and clinical (gestational sac) pregnancy were assessed. RESULTS: Overall, 24 male patients (36±1.5 years old) with NOA underwent mTESE for an average operating time of 110.6±6.9 minutes (range: 37-177). The primary sperm identification rate after mechanical dissociation of tissue was 37.5% (n=9). The use of the density gradient led to an overall sperm retrieval rate of 70.8% (n=17) (p<0.05) and secondary sperm retrieval rate (sperm identification in initially negative patients) of 53.3% (n=8). Retrieved sperm were cryopreserved to be used for ICSI. Thirteen couples (average female age and AMH 32.1±1.6 and 3.2±0.8 ng/ml respectively) underwent ICSI using extracted sperm. The overall fertilization, per-cycle pregnancy, and per-transfer pregnancy rates were 66%, 76%, and 100% respectively. Amongst these couples, 6 underwent PGT-A, and 70.0% of tested blastocysts were euploid. CONCLUSIONS: Utilization of mTESE with subsequent gradient technology may serve as a highly sensitive sperm detection and enrichment method for NOA patients in order to obtain superior ART outcomes. Source of Funding: NA © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e601 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nicholas Deebel More articles by this author Banafsheh Nikmehr More articles by this author Janmejay Hingu More articles by this author Collette O'Connor More articles by this author Rachel Ruble More articles by this author Yueqiang Song More articles by this author Ayse Vuruskan More articles by this author Anuradha Devineni More articles by this author Cihan Halicigil More articles by this author Stuart Howards More articles by this author Tamer Yalcinkaya More articles by this author Hooman Sadri-Ardekani More articles by this author Expand All Advertisement PDF downloadLoading ...

Neuropathology Evaluation in Juvenile Toxicity Studies in Rodents: Comparison of Developmental Neurotoxicity Studies for Chemicals With Juvenile Animal Studies for Pediatric Pharmaceuticals.

The developmental neuropathology examination in juvenile toxicity studies depends on the nature of the product candidate, its intended use, and the exposure scenario (eg, dose, duration, and route). Expectations for sampling, processing, and evaluating neural tissues differ for developmental neurotoxicity studies (DNTS) for chemicals and juvenile animal studies (JAS) for pediatric pharmaceuticals. Juvenile toxicity studies typically include macroscopic observations, brain weights, and light microscopic evaluation of routine hematoxylin and eosin (H&E)-stained sections from major neural tissues (brain, spinal cord, and sciatic nerve) as neuropathology endpoints. The DNTS is a focused evaluation of the nervous system, so the study design incorporates perfusion fixation, plastic embedding of at least one nerve, quantitative analysis of selected brain regions, and sometimes special neurohistological stains. In contrast, the JAS examines multiple systems, so neural tissues undergo conventional tissue processing (eg, immersion fixation, paraffin embedding, H&E staining only). An "expanded neurohistopathology" (or "expanded neuropathology") approach may be performed for JAS if warranted, typically by light microscopic evaluation of more neural tissues (usually additional sections of brain, ganglia, and/or more nerves) or/and special neurohistological stains, to investigate specific questions (eg, a more detailed exploration of a potential neuroactive effect) or to fulfill regulatory requests.

Microwave-Based Rapid Tissue Processing Technique: A Novel Aid in Histopathologic Laboratory.

Introduction:Conventional tissue processing takes a lot of time, but microwave processing method though rapid, its quality of tissue texture and staining properties is still questionable. Therefore, we conducted this study to find out the reliability of histological sections in the microwave method.Aim and Objectives:The aim is to assess whether microwave tissue processing, which is a rapid technique, is comparable to conventional tissue processing in terms of quality and reliability of histological sections.Materials and Methods:A total of 80 formalin-fixed tissue samples were taken and were divided into two pieces. One subjected to conventional tissue processing and the other subjected to microwave tissue processing. The slides were coded and evaluated by three independent observers using various parameters. All the data were subjected to Chi-square test.Results:Both the process did not differ in their efficiency in overall nuclear details, overall cytoplasmic detail, occurrence of artifact and tissue architecture, nuclear staining, cytoplasmic staining, and red blood cell staining. Although the other observers did not find any statistical significance, according to observer 3, conventional processing proved to have marginally significantly better epithelial connective tissue interface than microwave processing (P = 0.047).Conclusion:The microwave method of tissue processing is an economical procedure which reduces the obnoxious chemicals as well as the turnaround time.

Assessment of the ANDE 6C Rapid DNA system and investigative biochip for the processing of calcified and muscle tissue

The ANDE 6C Rapid DNA system could offer a potential alternative for the processing of calcified and soft tissue samples, often encountered in mass disaster scenarios. While originally designed for single source buccal swabs, interest in the performance of these instruments when using other types of single source samples continues to grow. To enhance the recovery of otherwise lesser quality samples, the manufacturer developed the investigative biochip, an alternative to the NDIS approved Arrestee biochip for reference sample buccal swabs. This study explores the viability of using the ANDE 6C system and the investigative biochip to process soft and calcified tissue, and uses conventional sample processing to contrast the results.Though the success rate obtained using the instrument’s expert system was lower than expected – 0% muscle, 11% ribs, and 50% teeth -, the ANDE 6C offers an advantage over conventional calcified tissue processing in terms of turn-around time and processing complexity. If robust analysis parameters can be established to allow the evaluation of the generated data by a qualified analyst on a third party software platform, the use of the ANDE 6C and investigative biochip could be a suitable alternative for currently employed procedures.However, as is the case with conventional DNA typing, the quantity, age, type of biological material and quality of the exemplars could all play a role in the success of the ANDE 6C typing process. In addition, it appears as if the calcified tissue pre-processing protocol that provides the better opportunity for the ANDE 6C success is not appropriate to be carried out in the field or by non-trained personnel as special equipment as well as a certain level of exe expertise and technique is necessary. Nevertheless, disaster victim and unidentified human remain samples could be processed in a laboratory setting using the Rapid DNA ANDE 6C platform provided sufficient material is available to conduct a second, ‘rescue’ sample processing if necessary.

Comparative Analysis of Immunohistochemistry of Hormone Receptors in Breast Cancer by Conventional and Microwave Tissue Processing Methods

Introduction: Rapid histopathological processing of neoplastic biopsies is crucial for initiating early therapy in patients. Microwave processing shortens the time to diagnosis and is less labour intensive. Aim: To compare the quality of immunohistochemical staining of Estrogen Receptors (ER) and Progesterone Receptors (PR) on paired breast samples using microwave processing versus conventional processing. Materials and Methods: A cross-sectional study was conducted at a tertiary care hospital in Kerala, India, from February 2014 to September 2015. A total of 44 paired samples from breast carcinoma patients were taken. Baseline characteristics of the patients such as age and type of carcinoma were noted. Haematoxylin and Eosin (H&amp;E) stain was used. One slide of the pair was processed conventionally and the other using a microwave. The stained slides were observed by three pathologists. The validity of ER and PR receptor status was evaluated with sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV). Kappa statistics and Spearman’s correlation test was used to denote the agreement between them. Results: The mean age was 51.32±11.16 years. There was agreement (Cohen k=0.902) between the microwave processed and conventionally processed paired breast samples for ER. The sensitivity and specificity of microwave processing in ER evaluation was 87.5% and 100% while that of PR evaluation was 92.9% and 100% respectively. The PPV was 100% and NPV was 93.3% for ER evaluation by microwave processing. Conclusion: Microwave aided tissue processing had significant advantages over conventional methods for providing a rapid diagnosis, being less laborious and had effective staining, which makes it a better choice.

Kerosene as an Alternative to Xylene in Histopathological Tissue Processing and Staining: An Experimental Study.

Background:Conventional tissue processing is as old as 100 years and still remains the gold standard. Tissue processing involves many steps, of which one of the important steps is clearing. Xylene is one of the common clearing agents used in laboratory, but it is carcinogenic and teratogenic.Aim:The aim of this study was to substitute conventionally used xylene with kerosene in tissue processing and staining.Materials and Methods:Thirty bits of chicken tissue samples were collected; each was randomly separated into two groups: tissue processing and staining. Instead of conventional xylene, we used kerosene. The tissue blocks were subjected to sectioning and staining, and finally, they were observed under light microscope.Results:Tissue samples that were processed and cleared with kerosene showed equal clearing and staining without any alterations of the tissue morphology and cellular details with that of xylene.Conclusion:Kerosene can be used as a substitute to xylene without posing any health risk or compromising the cellular integrity.

Xylene/Chloroform Free Microwave Tissue Processing and Staining a Non-hazardous and Time Effective Alternative

Introduction: Tissue processing using xylene/chloroform has been employed in histopathology reporting for the past 100 years. Microwave technique has not only reduced the processing time from 1 day to one hour but also doesn’t use xylene/chloroform and has been found to be on par with conventional processing. Xylene is expensive and detrimental to human health. The present study replaces chloroform with isopropanolol in tissue processing and xylene with liquid dish wash solution (LDW) in staining which is not only cheap but also non bio hazardous. Aim: To assess the efficacy of xylene free processing (microwave) and staining versus conventional tissueprocessing and hematoxylin and eosin are staining. Materials and methods: Two Tissue bits from 15 consecutively submitted samples at RL Jalappa Hospital after 1st Jan 2015 each of breast, cervix, lymph node, fat, thyroid, skin, alimentary tract, muscle, salivary gland, liver and kidney were taken and one was processed and stained using conventional method, other using xylene/chloroform free processing and conventional staining and other with both xylene/chloroform free processing and staining. The 495 sections were evaluated and scored by two pathologists independently for nuclear staining, cytoplasmic staining, uniformity, clarity and crispness. Results: In the samples evaluated xylene free processing and staining seems to be on par with conventional xylene processed and stained sections terms of nuclear and cytoplasmic detail, clarity and crispness. However Xylene cleared sections showed slightly better uniform staining (p value->0.05) Conclusion: Xylene/chloroform free processing and staining is not only a rapid but also safe alternative to conventional processing and staining using xylene. However more extensive studies need to be done on other types of tissues for validation

Comparison of Prostatic Tissue Processed by Microwave and Conventional Technique Using Morphometry.

Rapid processing of histopathological specimens and decreased turnaround time is important to fulfill the needs of clinicians treating sick patients, so the present study was conducted to compare the time taken and quality of sections in processing of prostatic tissue by rapid microwave and conventional techniques using morphometry. Four to five mm thick paired prostate tissue pieces of fifty cases of prostatectomy specimens were taken. One tissue piece of the pair was processed routinely overnight by conventional tissue processing and the other by microwave processing. Time taken for processing by both conventional technique and microwave technique was noted and compared. Then, both were stained with conventional method of hematoxylin and eosin staining and examined for histological typing and grading. Morphometric study was done on slides of prostatic tissue processed by both conventional and microwave technique. The prostatectomy specimens included both benign (86%) and malignant (14%) prostatic lesions in the age range of 46-85 years. The time taken for steps of dehydration, clearing and impregnation in microwave technique was significantly less as compared to histoprocessing done by conventional technique. Morphology, staining patterns of prostatic tissue processed within minutes by microwave technique, whether benign or malignant, were comparable to those sections which were processed in days using standard technique. Domestic microwave oven can be used for histoprocessing to accelerate the processing with preservation of morphology and is cheaper than commercially available microwave ovens and processing time was considerably reduced from days to minutes.

English

Aim: Tamoxifen, once praised for its importance in preventing breast cancer recurrence, is now implicated in dangerous side-effects. The authors are not aware of studies on the effect of tamoxifen on the histomorphological and biochemical components of the liver of guinea pig, hence the present one. Methods: Thirty guinea pigs weighing between 650g and 700g were assigned randomly into 6 groups of five and were separately given 0.70 and 7.0mg/kg body weight (b.w) tamoxifen for 2 and 4 weeks. Liver function tests and conventional tissue processing haematoxylin and eosin staining method were used in the study. Results: The results showed a significant loss in body weight (p&lt;0.05) of the guinea pigs administered with low and high doses of the tamoxifen for 4 weeks when compared with the controls. The mean serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total bilirubin and conjugated bilirubin increased significantly than the controls in high dose groups exposed for 2 weeks and 4 weeks respectively (p&lt;0.05). Similarly, histomorphological changes such as enlargement and sclerotic condition of central vein, enlargement and non-hexagonal radiating arrangement of sinusoids were observed in the liver of guinea pigs in the high dose tamoxifen Key words: Tamoxifen, Liver, Breast cancer

Endoscopic and Histologic Diagnosis of Upper Gastrointestinal Lesions, Experience in a Port City of Bangladesh

Background: For upper gastrointestinal tract disorders endoscopic biopsy is common procedure performed in the hospital for a variety of benign and malignant lesions. Endoscopy is incomplete without biopsy and histopathology is the gold standard for the diagnosis of endoscopically detected lesions.Methods: A prospective study was carried out at a private histopathology diagnostic center at Chittagong from October 2012 to September 2013. All the upper GIT endoscopic biopsy samples received during the period were included in the study. The endoscopy was done by a skilled endoscopist and his detail endoscopic findings were noted. After conventional tissue processing H&amp;E stained slides are examined under light microscope by three competent histopathologists.Results: Among total 110 upper GIT endoscopic biopsy samples 22 (20%) were oesophageal, 73 (66.36%) gastric and 15 (13.64%) duodenal biopsies. Among oesophageal biopsies 18 (81.82%) were histologically neoplastic of which 13 (81.25%) were SCC and 03 (18.75%) adenocarcinoma. Rest 02 (9.09%) were leiomyoma. Among all the oesophageal carcinomas, 10 (62.5%) were provisionally diagnosed as carcinoma by endoscopists. Among 73 endoscopic biopsies from stomach, the mean age was 54.63 yrs. On histopathology among 73 patients, adenocarcinoma-33 (45.20%), gastric ulcer-11 (15.07%), gastritis-15 (20.55%) and hyperplastic polyp-14 (19.18%). Among 33 adenocarcinoma of stomach 23 (69.69%) were clinically diagnosed or suspected as carcinoma by the endoscopist. Among 15 duodenal biopsies 11 (73.33%) were diagnosed histologically as hyperplastic polyp, 02 (13.33%) as adenocarcinoma, 02 (13.33%) as ulcer. Among 110 UGIT biopsies total 51 (46.36%) were malignant. Mean age 59.49 yrs ranges from 22 Yrs to 82 Yrs. M:F ratio is 1.4:1. Among all 33 (64.7%) were gastric carcinoma, 16 (31.37%) oesophageal carcinoma and 02 (3.92%) duodenal carcinoma. Among 51, 35 (68.63%) were clinically diagnosed or suspected as carcinoma by endoscopist. No clinical information was available in 03 (5.88%) cases and rest 13 (25.49%) cases were clinically diagnosed as non neoplastic conditions by the endoscopist. Conclusion:Endoscopy followed by histopathological examination play important role for diagnosis and management of UGIT lesions.DOI: http://dx.doi.org/10.3329/cmoshmcj.v13i3.20997

Role of microwaves in rapid processing of tissue for histopathology

<b>Aim:</b> The primary aim of the following study is to study the utility of microwave stimulated rapid processing of tissues for histopathology and the secondary aim is to compare the quality of the final product obtained after microwave stimulated rapid tissue processing with the conventional method. <b>Materials and Methods:</b> During the 3 years period of study, 150 cases were studied which were randomly selected from the tissues sent for histopathology. Tissues were processed by conventional method and by microwave assisted tissue processing. <b>Results:</b> Slides obtained by microwave and conventional tissue processing were statistically analyzed by using Chi-square test. The results obtained showed that the cellular and nuclear features of microwave processed tissues were comparable to conventionally processed tissue. Microwave assisted tissue processing reduced the total time for preparing tissue blocks to about an hour. <b>Conclusion:</b> Microwave stimulated processing provides an attractive alternative over traditional conventional processing.

Microwave processing of gustatory tissues for immunohistochemistry

We use immunohistochemistry to study taste cell structure and function as a means to elucidate how taste receptor cells communicate with nerve fibers and adjacent taste cells. This conventional method, however, is time consuming. In the present study we used taste buds from rat circumvallate papillae to compare conventional immunohistochemical tissue processing with microwave processing for the colocalization of several biochemical pathway markers (PLCβ2, syntaxin-1, IP3R3, α-gustducin) and the nuclear stain, Sytox. The results of our study indicate that in microwave versus conventional immunocytochemistry: (1) fixation quality is improved; (2) the amount of time necessary for processing tissue is decreased; (3) antigen retrieval is no longer needed; (4) image quality is superior. In sum, microwave tissue processing of gustatory tissues is faster and superior to conventional immunohistochemical tissue processing for many applications.

Domestic Microwave Versus Conventional Tissue Processing: A Quantitative and Qualitative Analysis

Microwave irradiation has been tried as a replacement for the conventional tissue processing technique in histopathology laboratories for quite some time. Studies have shown that Domestic Microwave Tissue Processing (DMWTP) provides a faster delivery of the tissue sections with a morphology which is similar to that which is seen Conventional Tissue Processing (CTP). But many laboratories still confine the domestic microwave tissue processing method only to the handle selected specimens, for which urgent reports are needed. One of the probable reasons is that, understanding about the number of tissue sections which can be processed using a microwave oven at a time, with the appropriate quality, still remains unclear. The aim of this study was to quantitatively analyze the optimum number of samples that a domestic microwave could process at a time, as well as to qualitatively analyze the morphological outcome of those tissue sections with that of conventional processing. This study was approved by the research and ethical committee of Sree Balaji Medical College and Hospital. A total of 135 paired tissue sections were included in the study. Ten tissue sections (which are mentioned hereafter as A10) were processed in a domestic microwave and their paired 10 tissues were processed by a conventional method. Subsequently, the number of tissues which was to be processed was increased to B15, C20, D25, E30 and F35, after ascertaining that the morphological qualities of the previously processed tissue sections were satisfactory. Sections of 4 μm thickness were taken and they were stained by the Haematoxylin and Eosin method. The slides of the tissues which were processed by the microwave method and the conventional method were randomly numbered, for a blind study, which were independently evaluated by two observers. The qualities of slides were assessed, based on 4 parameters: the cytoplasmic details, the nuclear details, the tissue architecture and the staining characteristics. The statistical analysis was done by using SPSS 15.0. The morphological outcomes (quality) of the DMWTPs were comparable to that of the CTPs, when the sample load (quantity) in the microwave oven was up to 25 samples. Domestic microwave processing can be effectively used in laboratories with a maximum sample size of 25 samples per load. This has the advantage of being rapid, with its morphological quality being identical to that of conventional processing.

Tissue processing of oral biopsy specimens: An adjunct to diagnosis

Conventional tissue processing dates back to 100 years and still remain the gold standard against which all new technologies and methods are assessed. A laborious and tedious manual sequence, tissue processing is of paramount importance for having good thin sections without artefacts. Tissues and cells examined outside the body with an imaging system are an artefact of the original. The structure of a tissue is determined by the shape and size of macromolecules in and around the cells. Histopathology is a comparative science where like is compared with like and like with unlike. Various techniques have been developed to prepare tissues for study so that they closely resemble their natural, living state. Biopsied tissue has to be stained for microscopical examination. The tissues have to be enabled for sectioning, and the series through which it is prepared is called tissue processing. This review article highlights the three methods of tissue processing and their benefits. The review was selected by typing tissue processing in the Google search engine, Pubmed, and Pubmed Central. Literature review of articles reflecting different methods, variation from the conventional tissue processing method, and latest technique to enhance the quality of the tissue to be processed was performed.

Use of microwave in diagnostic pathology

Conventional tissue fixation and processing is as old as 100 years and still remains the gold standard against which all new technologies and methods need to be assessed. Tissue processing is one of the important steps for obtaining good thin sections without artifacts. Though conventional tissue-processing methods are most commonly followed, they are well-known as very laborious and tedious procedures. Microwaves a form of electromagnetic wave-induced heat, when applied in histotechnology, reproducibly yields histolologic material of similar or superior quality to that provided by conventional processing methods, making it more popular in the recent years. A laboratory microwave offers features like maximum output of 2000-3000 watts, an in-built source of adjustable temperature probe, facility for ventilation of hazardous fumes, but is expensive. Considering the usefulness of microwave in histotechnology, i.e., reducing the time required for the diagnosis, replacing the conventional equipments of laboratories by microwave-guided ones is a remarkable and an acceptable change.

Comparison of conventional tissue processing with microwave processing using commercially available and domestic microwaves

Context: Microwave-accelerated tissue processing is believed to have brought a revolutionary improvement in the field of histopathology and histochemistry. This technique shortens the time for tissue processing from days to minutes. The technique fulfills the needs of the patient as well as those of the physician by improving the use of reagents while reducing or eliminating their toxicity, and places the laboratory in a better position to meet the demands of the surgeon. Aim: This study is being conducted to determine the efficacy of the microwave tissue processing method for orofacial biopsy specimens by comparing two different techniques of microwave histoprocessing with the conventional method, based on the clarity of nucleocytoplasmic differentiation and staining of tissues processed by each method . Materials and Methods: Twenty oral mucosal biopsy specimens were cut into three equal parts and each part was processed by three processing techniques. Hematoxylin and eosin staining was performed at the same time and grading was done by four oral pathologists . Statistical Analysis Used: The one-way ANOVA test using SPSS 17 was used in this study. Result: The parameters (color intensity, contrast, uniformity of staining, cytoplasmic and nuclear details) appeared slightly better in a commercial microwave, followed by the domestic microwave method and the routine method. The P values were statistically insignificant for all the parameters except color intensity . Conclusion: Microwaves can be used for tissue processing, which shortens the time for tissue processing without affecting the architecture of the cells and with increased intensity of staining.

A high-throughput comparative characterization of laser-induced soft tissue damage using 3D digital microscopy

3D digital microscopy was used to develop a rapid alternative approach to quantify the effects of specific laser parameters on soft tissue ablation and charring in vitro without the use of conventional tissue processing techniques. Two diode lasers operating at 810 and 980 nm wavelengths were used to ablate three tissue types (bovine liver, turkey breast, and bovine muscle) at varying laser power (0.3, 1.0, and 2.0 W) and velocities (1-50 mm/s). Spectrophotometric analyses were performed on each tissue to determine tissue-specific absorption coefficients and were considered in creating wavelength-dependent energy attenuation models to evaluate minimum heat of tissue ablations. 3D surface contour profiles characterizing tissue damage revealed that ablation depth and tissue charring increased with laser power and decreased with lateral velocity independent of wavelength and tissue type. While bovine liver ablation and charring were statistically higher at 810 than 980 nm (p < 0.05), turkey breast and bovine muscle ablated and charred more at 980 than 810 nm (p < 0.05). Spectrophotometric analysis revealed that bovine liver tissue had a greater tissue-specific absorption coefficient at 810 than 980 nm, while turkey breast and bovine muscle had a larger absorption coefficient at 980 nm (p < 0.05). This rapid 3D microscopic analysis of robot-driven laser ablation yielded highly reproducible data that supported well-defined trends related to laser-tissue interactions and enabled high throughput characterization of many laser-tissue permutations. Since 3D microscopy quantifies entire lesions without altering the tissue specimens, conventional and immunohistologic techniques can be used, if desired, to further interrogate specific sections of the digitized lesions.

Implementation of a new rapid tissue processing method – Advantages and challenges

Conventional tissue processing of histologic specimens has been carried out in the same manner for many years. It is a time-consuming process involving batch production, resulting in a 1-day delay of the diagnosis. Microwave-assisted tissue processing enables a continuous high flow of histologic specimens through the processor with a processing time of as low as 1 h. In this article, we present the effects of the automated microwave-assisted tissue processor on the histomorphologic quality and the turnaround time (TAT) for histopathology reports. We present a blind comparative study regarding the histomorphologic quality of microwave-processed and conventionally processed tissue samples. A total of 333 specimens were included. The microwave-assisted processing method showed a histomorphologic quality comparable to the conventional method for a number of tissue types, including skin and specimens from the gastrointestinal, urogenital, and female genital tract. We studied the TAT for all histologic specimens received in a period of six consecutive weeks in 2006 and 2007, respectively. We found a positive impact on TATs after introducing microwave-assisted processing in the laboratory. Turnaround times, in general, were improved, and same-day-reporting, in particular, showed an increase from 0% to 15%.

Anisotropic Nature of Mouse Lung Parenchyma

Lung parenchyma is normally considered to be isotropic, that is, its properties do not depend upon specific preferential directions. The assumption of isotropy is important for both modeling of lung mechanical properties and quantitative histologic measurements. This assumption, however, has not been previously examined at the microscopic level, in part because of the difficulty in large lungs of obtaining sufficient numbers of small samples of tissue while maintaining the spatial orientation. In the mouse, however, this difficulty is minimized. We evaluated the parenchymal isotropy in mouse lungs by quantifying the mean airspace chord lengths (Lm) from high-resolution histology of complete sections surrounded by an intact continuous visceral pleural membrane. We partitioned this lung into 5 isolated regions, defined by the distance from the visceral pleura. To further evaluate the isotropy, we also measured Lm in two orthogonal spatial directions with respect to the section orientation, and varied the sample line spacing from 3 to 280 microm. Results show a striking degree of parenchymal anisotropy in normal mouse lungs. The Lm was significantly greater when grid lines were parallel to the ventral-dorsal axis of the tissue. In addition the Lm was significantly smaller within 300 microm of the visceral pleura. Whether this anisotropy results from intrinsic structural factors or from nonuniform shrinkage during conventional tissue processing is uncertain, but it should be considered when interpreting quantitative morphometric measurements made in the mouse lung.