Patent ID: 12241818

The drawings are not necessarily to scale and may be illustrated by phantom lines, diagrammatic representations and fragmentary views. In certain instances, details that are not necessary for an understanding of the embodiments or that render other details difficult to perceive may have been omitted.

DETAILED DESCRIPTION

The present disclosure provides methods and systems for preparing cytological samples for testing and diagnoses in histological and pathological procedures. In some embodiments, the disclosed methods may include providing a concave-shaped filter within which cytological samples are collected. A vacuum device may apply a negative pressure to withdraw liquid from the sample, leaving cellular material within and along an internal surface of the concave filter. The cellular material may be distributed along a bottom of the filter and along sidewalls of the filter. A liquid matrix material may be provided over the cellular material within the concave filter, and the matrix material may be hardened (e.g., gelled or solidified) either chemically or by cooling the liquid matrix material, such as with an appropriately shaped metal tamper. One example suitable sectionable matrix material that may be used with embodiments of the present disclosure is described in U.S. Pat. No. 9,851,349, titled “MATRIX FOR RECEIVING A TISSUE SAMPLE AND USE THEREOF,” issued on Dec. 26, 2017 (hereinafter “the '349 patent”), the entire disclosure of which is incorporated herein by reference. Additional examples of liquid matrix material include wax or another material that may be sectioned in a resulting cell block. A resulting assembly of the cells and hardened matrix material may be obtained for further histological processing (e.g., one or more of: fixation, dehydration, embedding, sectioning, staining, multiplexing, or slide preparation, etc.) and pathological analysis.

In some embodiments, the filter may initially be substantially planar and may be formed into a concave shape as a result of the filtration step. By way of example and not limitation, a pre-folded filter may be configured to transition from a generally planar, folded initial shape to an unfolded concave shape during filtration.

In some examples, the filter (e.g., either initially concave or to be transitioned into a concave shape, as noted above) may be positioned over a concave sectionable pre-gelled lower matrix material. The lower matrix material may include a number of channels passing from an inner concave surface to a bottom outer surface of the lower matrix material. An initially liquid sectionable matrix material may be applied over the filtered cellular material and may be hardened (e.g., gelled or solidified), as described above. The resulting matrix and cellular assembly, including the lower matrix material, filter, cellular material, and hardened upper matrix material, may be submitted for further histological processing (e.g., one or more of: fixation, dehydration, embedding, sectioning, staining, multiplexing, or slide preparation, etc.) and pathological analysis.

Alternatively or additionally, a pre-solidified (e.g., pre-gelled) and pre-shaped convex upper matrix material may be positioned over the filtered cellular material within concave portion of the lower matrix material. The matrix and cellular assembly, including the lower matrix material, filter, cellular material, and pre-gelled upper matrix material may be submitted for further histological processing (e.g., one or more of: fixation, dehydration, embedding, sectioning, staining, multiplexing, or slide preparation, etc.) and pathological analysis. In some embodiments, the pre-shaped sectionable matrix material may be or include wax, proteins, lipids, a combination thereof, or any other suitable matrix material that may be sectioned from a resulting cell block together with the cellular material.

Alternatively or additionally, prior to disposing an upper matrix material (e.g., an initially liquid upper matrix material or a pre-gelled upper matrix material) over the filtered cellular material, an additional filter may be positioned over the filtered cellular material. The upper matrix material may then be positioned over the additional filter, and the assembly may be submitted for further histological processing (e.g., one or more of: fixation, dehydration, embedding, sectioning, staining, multiplexing, or slide preparation, etc.) and pathological analysis.

Alternatively or additionally, in some examples, an initially liquid matrix material may be positioned over the assembly that includes the upper matrix material, additional filter, filtered cellular material, concave filter, and lower matrix material assembly and may be hardened (e.g., gelled or solidified, such as chemically or thermally). In this manner, assembly including the upper matrix material, additional filter, filtered cellular material, concave filter, and lower matrix material may be sealed and held in place securely.

The methods and systems described in the present disclosure may enable the obtaining of cell blocks from cell suspensions (e.g., low cellularity samples) with low—to substantially zero-cell losses during the preparative steps. In addition, the disclosed methods may be performed faster than some conventional techniques and may be compatible with all fixatives that are typically employed in cytopathology. In addition, embodiments of the disclosed methods and systems may be compatible with microwave-assisted tissue processing, cryo-sectioning, and other histological procedures. The cellularity of the slides resulting from embodiments of this disclosure may be predictable and controllable. Cross-contamination may be inhibited (e.g., reduced or eliminated) by containing all cells within the concave filter when the assembly of cells and matrix material is removed for histological processing. The methods and systems may be cost-effective, particularly when compared with certain conventional methods. The resulting assemblies of cells and matrix material may enable or facilitate multiplexing, and sectionable code or other identifiers may be used with the assemblies for identification and standardized processing of the cytological samples.

FIG.1is a flow diagram illustrating an example method for preparing cytological samples for histological processing. As shown at operation110, in some examples of the present disclosure, a raw or prefixed cytological sample may be placed in a cavity of a concave filter (e.g., a membrane including cellulose acetate, cellulose nitrate, and/or mixed esters of cellulose) in a filtration system. The concave filter may have, for example, a porosity of 0.11 microns, 0.22 microns, 0.45 microns, 3 microns, 5 microns, 8 microns, or another suitable porosity. The porosity of the filter may be selected depending on a type of liquid being processed, a known cell size (e.g., to be smaller than the known cell size), etc. Prior to this primary filtering, a preliminary concentration (e.g., using a centrifuge or another filter) can be performed, such as for a high-volume, low cellularity (e.g., “thin” or “watery”) samples. Optionally, cellular samples with undesirable characteristics (e.g., high protein content, the presence of mucus, the presence of blood, etc.) may be cleaned, purified, concentrated, etc. The porosity, diameter of the filter, radius of the cavity, and depth of the filter can be adjusted or selected depending on the type of cytology specimen being processed. The filter may be pre-formed to exhibit a concave shape or may be pre-folded to result in a concave shape when a low pressure is applied below the filter. In some examples, the filter may be positioned in or over a concave cavity in a pre-formed, sectionable lower matrix material. The lower matrix material may include channels extending from an inner concave surface of the cavity to a bottom surface thereof for applying a negative pressure to the concave cavity for filtration.

As shown at operation120, a vacuum device (e.g., a pump) may apply a negative pressure to an outer side of the concave filter (e.g., through the channels in the lower matrix material) to withdraw a liquid from the cytological sample, while depositing the cells within the sample on inner surfaces of the filter. The level of the applied negative pressure may be selected to at least maintain an integrity of the cells. At the same time, the level of the applied negative pressure may be selected to result in a reasonably fast filtration, such as for efficient processing and cell block preparation.

The filtered cells may tend to generate a thin layer of filtered cells formed on internal surfaces of the concave filter. The layer of filtered cells may be slightly thicker at the bottom of the cavity or near a top of the cavity, depending on a buoyancy or mass of the cells and/or on a distribution of channels in a pre-formed lower matrix material below the filter, and/or the level of vacuum applied for example. The concave shape of the filter may enable a distribution of the cells that facilitates obtaining multiple sections of a resulting cell block that each contains cells therein for processing and analysis. For example, the cellular material may be distributed substantially evenly along an inner surface of the concave filter.

As a part of subsequent histological processing, a resulting assembly of the matrix material, the filter, and the filtered cellular material may be sectioned. By providing the filtered cellular material in a substantially even distribution along the concave inner surface of the filter, each section obtained may include sufficient cellular material for useful examination by a pathologist, as will be explained further below. This may enable the use of relatively few sections for review by a pathologist, while leaving additional portions of the assembly for further processing as may be desired, and/or while providing additional sections for different processing techniques (e.g., by application of a different histological stain, etc.). In some examples (e.g., depending on the characteristics of the cytological sample to be examined), the methods and systems described herein may result in a plurality of usable sections, each of which may include at least fifty, at least one hundred, at least two hundred, at least three hundred, at least four hundred, or at least five hundred visible cells for review by the pathologist. In some embodiments, at least twenty, at least fifty, at least one hundred, or at least two hundred sections each having such a suitable number of visible cells may be obtained from a single assembly of matrix material, filter, and filtered cellular material.

As shown at operation130, after the liquid or a sufficient portion of the liquid of the cytology specimen is removed via the applied negative pressure, a sectionable matrix material may be applied over the filtered cells within the concave filter. By way of example, a liquid or molten sectionable matrix material may be applied over the filtered cells within the concave filter, such as until the cavity is substantially full with a slight meniscus. In some examples, the temperature of the molten sectionable matrix may be maintained below about 60 degrees Celsius to prevent denaturation of proteins present in the cell sample (which may nullify a downstream diagnostic value of the sample). Various sectionable matrix materials may be used, but the fluidity and solidification speed may be appropriately tuned such that, before solidification is complete, the matrix will encapsulate substantially all cells or cellular aggregates, tissue fragments, or other material of interest that may be present on the concave filter. After hardening, the initially liquid matrix material applied over the filtered cells may form an upper matrix material.

By way of another example, a pre-gelled and pre-shaped upper matrix material may be applied over the filtered cells within the concave filter. For example, the upper matrix material may be molded or otherwise formed to have a convex shape that is complementary to a concave region of the filter and/or to the underlying lower matrix material, if present. Example pre-formed upper matrix materials are further described below.

Whether initially liquid or pre-gelled, one suitable example sectionable matrix material that may be used in the disclosed methods and systems (e.g., as the lower matrix material and/or as the upper matrix material) is described in the '349 patent,

In embodiments in which the upper matrix material includes an initially liquid material, after the liquid or molten matrix material is applied, the sectionable matrix material may be hardened (e.g., solidified or gelled), to form an assembly of cells and matrix material. For example, a cooling device, such as a chilled tamper, may be applied on top of the liquid-filled cavity and held in position until the sectionable matrix sufficiently gels or solidifies. The temperature of the tamper may initially be (or may be maintained) at or above about zero degrees Celsius for preventing damage to the cells, such as may otherwise result from freezing and/or cracking of the cells. By tuning the composition of the sectionable matrix, gelling times of about fifteen seconds to about 2 minutes or less may be attainable, depending on the size of the cell block. Additionally, or alternatively, the matrix may be of a type that is solidified or gelled in another way, such as by a chemical reaction.

As shown at operation140, the assembly of cells and sectionable matrix may be removed from the filtration system. The assembly may then be histologically processed, such as using a method well-known to the person skilled in the art. In some embodiments, the cell block prepared from pre-fixed cells can proceed directly to a dehydration step without any additional fixation (e.g., in formalin). Moreover, the assembly obtained using the disclosed method can be also employed for cryo-sectioning (i.e., without any fixation, dehydration, clarification, and paraffin embedding)

During embedding of the cell blocks (e.g., in paraffin wax), the assembly of cells and sectionable matrix can be oriented either with the lower matrix material or the upper matrix material down (e.g., to be sectioned first). Additionally or alternatively, the assembly may be bisected, trisected, etc., depending on its size and/or on future diagnostic applications envisioned by a diagnostician.

The assembly may be submitted for further histological processing (e.g., one or more of: fixation, dehydration, embedding, sectioning, staining, multiplexing, or slide preparation, etc.) and pathological analysis. At least. some resulting slides formed by sectioning the processed assembly may display a rim of cells at a periphery of the sectionable matrix (e.g., sandwiched between the filter if it was maintained in place and the sectionable matrix, sandwiched between two filters, etc.) or a disc of cells, substantially devoid of sectionable matrix (except for potentially a thin layer encapsulating individual cells or cellular aggregates). If the filter was retained in the block, the filter may be present as a ring around the disc of cells. If a pre-formed (e.g., pre-gelled) upper matrix material b employed without applying a liquid upper matrix material to the filtered cellular material, the cells may not be encapsulated by the matrix material.

If desired, the cell blocks- or fragments of them (before or after sectioning)—can be multiplexed, such as in an appropriately shaped receptacle formed of a sectionable matrix, as described in the '349 patent or including wax or another sectionable matrix material. Thus, multiple cell blocks or cell block fragments (e.g., from the same patient or from different patients) can be processed together in a same sectionable matrix receptacle. The sectionable matrix receptacle may have features (e.g., sectionable code, measurement marks, dividers, depth gauges, identifiers, etc.) that may enable separation and/or identification of the cell blocks or fragments, Example systems and methods that may be suitable for providing sectionable matrix receptacles with such features are described in the disclosure of U.S. patent application Ser. No. 15/893,061, titled “Systems and Methods for Tissue Sample Processing,” filed on Feb. 9, 2018, published as U.S. Patent Application Publication No. 2018/0226138, the entire disclosure of which is incorporated herein by reference.

By way of example, the position and distribution of channels passing through the lower matrix material may serve as a pre-determined pattern (e.g., a grid) for three-dimensional reconstruction of the distribution of the assembly of cells and matrix material. Such reconstruction may facilitate the process of microtome sectioning of a resulting cell block and may reduce (e.g., eliminate) a risk of generating and presenting sections devoid of cells or of removing too much material from the cell block and losing cellular material. Individual serial sections obtained from the resulting cell block may be stained and examined under a microscope, and/or images (e.g., digital images) may be obtained and archived for later examination. The location, shape, and/or distribution pattern of the channels extending through the lower matrix material may be visible on the resulting slides, which may enable the reviewer (e.g., a pathologist) to ascertain the depth within the cell block at which a particular section was taken. Additionally, by providing the channels in a predetermined pattern (e.g., shape, distribution, size, etc.), the channels will appear in the stained sections as unstained holes. Thus, tracking and tracing various histological features may be facilitated by the presence and configuration of the channels in the lower matrix material. Example configurations of channels in the lower matrix material are further described below.

In some embodiments, a variety of pigments (e.g., colors, fluorophores, etc.) may be employed for distinguishing the lower matrix material, the upper matrix material, or both of the lower and upper matrix materials from each other and/or from the cellular material. By way of example, this may facilitate identifying a depth at which a particular section was taken, and may reduce (e.g., eliminate) producing slides having sections that are devoid of cellular material. Additionally or alternatively, such distinguishing stains may reduce a risk of removing too much material from the cell block and, therefore, losing cellular material from the cell block. In some embodiments, a backlight may further facilitate the proper obtaining and use of sections from the cell block, by highlighting pigment differences between the lower matrix material, the upper matrix material, and/or the filtered cellular material.

The multiplexing can be done prior to fixation or during embedding, for example. The sectionable matrix may be in the same stage of the processing protocol as the cell block to be multiplexed. In addition to providing sectionable matrix receptacles with sectionable code, other methods of identifying certain cell blocks can be envisioned, for example, using color-coded liquid matrices, color-coded multiplexing matrices, RFIDs, etc. If desired, after sectioning the multiplexed cell blocks, each individual cell block can be removed from the sectionable matrix material and multiplexed or processed/tested individually again, in another configuration.

Embodiments of the multiplexing procedures described in the present disclosure may provide a number of benefits over conventional methods, such as cost and time efficiencies. The multiplexing may be facilitated by the methods and systems of the present disclosure by providing the cell blocks in a standardized size, shape, and configuration, which may be placed into standardized sectionable matrix receptacles for case of processing, identification, and handling. In addition, the number of sections that may be obtained from the cell blocks generated using the systems and methods described in the present disclosure may be higher (e.g., substantially higher) than conventional methods, due to the concave shape of the filter used to form the cell blocks.

Testing of the presently disclosed system and methods was completed with a cytological sample including about 41,800 cells (immortalized kidney epithelial cells) suspended in a 0.250 ml solution and filtered through a concave filter having a concave cavity diameter of about 8 mm and a cavity depth of about 2.5 mm, with a porosity of 5 microns. The resulting paraffin block generated in excess of 250 serial sections taken at about 5-micron interval. Each 25thsection was stained and all cells present were counted under the microscope at a 400× magnification. The following values were recorded (counts/number of section): 682/1st, 388/25th, 293/50th, 190/75th, 122/100th, 271/125th, 266/150th, 141/175th, 73/200th, 101/225th, and 84/250th. It is evident that these counts could suggest that the number of cells present on the filter (and by way of consequence in the paraffin sections) is slightly larger than the cells that were deposited on the surface of the filter. However, some cells may be intercepted during microtome sectioning in more than one section (depending on the size of cell in 2, 3, or even more successive sections), However, the number of cells lost during obtaining a cell block by employing the presently disclosed methods and systems is virtually nil.

FIG.2is a side perspective view of a system200(e.g., a filtering system) for preparing cytological samples, such as for further histological processing, according to embodiments of the present disclosure.FIG.3is an upper perspective view of the system200ofFIG.2.FIG.4is another perspective view of the system200ofFIG.2, with a cooling device applied.

Referring toFIGS.2-4, the system200may include a vacuum device202(e.g., a pump), a filtering chamber204, and a conduit206fluidly coupling the vacuum device202to the filtering chamber204. The filtering chamber204may be shaped and sized for receiving a concave filter208.FIG.4also shows a cooling device in the form of a chilled tamper210(e.g., including a metallic material) in place over the filtering chamber204, which may be chilled and applied for hardening an initially liquid upper matrix material that may be applied to the filtering chamber204and over a cellular material after filtering. In some examples, the tamper210may have a generally planar lower surface for contacting and hardening the upper matrix material. In additional examples, the tamper210may have a convex lower surface, which may be complementary to a concave cavity formed in the concave filter208.

FIG.5is a side perspective view of an example concave filter300according to the present disclosure. For example, the concave filter300may include a concave portion302and a handle portion304for installing and removing the concave filter300in the filtering chamber204.

FIG.6is a schematic side cross-sectional view of a system600for preparing cytological samples, according to at least one additional embodiment of the present disclosure. The system600may include a funnel602, a lower matrix material receptacle604, a filtrate reservoir606, and a vacuum conduit607positioned for applying a negative pressure to the filtrate reservoir606. The lower matrix material receptacle604may be shaped and sized for receiving a pre-formed (e.g., pre-gelled) lower matrix material608and a concave filter610. The lower matrix material608may include a concave cavity612, within which a portion of the concave filter610may be positioned prior to a filtering operation. As discussed above and as further discussed below, the lower matrix material608may include channels (not shown in the view ofFIG.6) extending from an inner surface of the concave cavity612to a bottom surface of the lower matrix material608.

In some embodiments, a liquid-blocking filter614may be positioned across the vacuum conduit607to reduce or prevent the passage of liquid or aerosols (e.g., biohazardous solution) from a cytological sample616to an associated vacuum device618(e.g., a pump), while allowing a gas (e.g., air) to pass. The cytological sample616may be or include a cellular material suspended in a liquid, such as water. The funnel602may facilitate deposition of the cytological sample616over and into the concave filter610. In some examples, the funnel602may be removable from over the concave filter610, such as to install and remove the lower matrix material608and the concave filter610relative to the lower matrix material receptacle604.

FIG.7is a perspective view of a system700for preparing cytological samples, according to at least one further embodiment of the present disclosure.FIG.8is a side cross-sectional view of the system700ofFIG.7. Referring toFIGS.7and8, the system700may include a lower matrix material receptacle704positioned over a filtrate reservoir706, a vacuum conduit707extending from a side of the filtrate reservoir706, and a vacuum device718that may be configured to apply a negative pressure to the filtrate reservoir706via the vacuum conduit707. In addition, the system700may include a drain720for removing a liquid from the filtrate reservoir706after a filtration operation. A control unit722may be positioned and configured to control operation (e.g., turn off and on, alter a value of an applied negative pressure, etc.) of the vacuum device718.

FIG.9is a top view of the lower matrix material receptacle704(also referred to as “receptacle704” for simplicity) of the system700ofFIG.7. As shown inFIG.9, an inner surface of the receptacle704within a concave cavity712of the receptacle704may include at least one recess724. For example, the recess724may have a spiral configuration. Other configurations are also suitable, such as radially extending recesses724, concentric recesses724, etc. The recess724may provide fluid communication between channels formed in a lower matrix material positioned within the recess724and at least one hole726extending through the receptacle704. In this manner, a negative pressure may be applied by the vacuum device718(FIGS.7and8) through the channels via the recess724and the hole726. At the same time, portions of the receptacle704between portions of the recess724may physically support a corresponding lower matrix material positioned within the recess724.

FIG.10is a side cross-sectional view of a lower matrix material1000for use with systems for preparing cytological samples (e.g., with the systems200,600,700described above), according to at least one embodiment of the present disclosure.FIG.11is a top view of the lower matrix material1000ofFIG.10. As discussed above, the lower matrix material1000may be or include a pre-formed (e.g., pre-gelled) sectionable matrix material. The lower matrix material1000may include a central depression1002, within which a concave filter may be positioned for a filtering operation. A plurality of channels1004may extend from an inner surface1006of the centra6depression1002to a bottom surface1008of the lower matrix material1000, providing fluid communication across the lower matrix material1000. Thus, when the lower matrix material1000is positioned within a corresponding receptacle (e.g., the receptacle704shown inFIG.9), a negative pressure may be applied to the central depression1002via the channels1004.

The channels1004may be distributed across the inner surface1006of the central depression1002, such that a substantially consistent pressure may be applied across the inner surface1006. This may facilitate the deposition of cellular material in a cytological sample substantially evenly across a concave filter positioned within the central depression1002. As shown inFIG.11, at least some of the channels1004may have different cross-sectional shapes (e.g., circular and rectangular) and/or sizes. For example, the variety of cross-sectional shapes and/or sizes of the channels1004may facilitate obtaining a proper or known orientation of a section or slide obtained from a corresponding pathological cell block.

FIG.12is a side cross-sectional view of an assembly1200including a lower matrix material1202, a first (e.g., lower) concave filter1204, a filtered cellular material1206, a second (e.g., upper) concave filter1208, and an upper matrix material1210for use with systems for preparing cytological samples, according to at least one embodiment of the present disclosure. As discussed above with reference toFIGS.10and11, the lower matrix material1202may include channels1212extending therethrough.

The assembly1200may be formed by positioning the lower matrix material1202in a corresponding receptacle of a vacuum device (e.g., the receptacle704of the system700discussed above with reference toFIGS.7-9) and placing the first concave filter1204over the lower matrix material1202. A cytological sample (e.g., a liquid solution including a suspension of cellular material) may be applied to the first concave filter1204, and a negative pressure may be applied through the channels1212. The filtered cellular material1206may be deposited on the first concave filter1204substantially evenly across a concave surface of the concave filter1204. Optionally, the second concave filter1208may be positioned over the filtered cellular material1206, such as to hold the filtered cellular material1206in place during subsequent handling. The upper matrix material1210may be applied over the filtered cellular material1206(and over the second concave filter1208, if present). For example, a liquid upper matrix material1210may be applied and hardened, or a pre-formed (e.g., pre-gelled) upper matrix material1210may be disposed over the filtered cellular material1206. The assembly1200may then be submitted for further histological processing.

FIG.13Ais a side cross-sectional view of the assembly1200ofFIG.12, showing a location where a first section1300may be taken at line13B-13B.FIG.13Bis a top cross-sectional view of the assembly1200ofFIG.13A, showing an appearance of the first section1300taken at line13B-13B. The first section1300may be taken at a lower portion of the inner concave surface of the lower matrix material1202. As shown inFIG.13B, a small central region1302may be evident in the first section1300where the assembly1200was cut just at or above the lower matrix material1202. However, the filtered cellular material1206may not have been reached by the first section1300, such that none of the filtered cellular material1206is present in the first section1300. Since no filtered cellular material1206is present in the first section1300, the first section1300may be discarded prior to further histological processing.

FIG.14Ais a side cross-sectional view of the assembly1200ofFIG.12, showing a location where a second section1400may be taken at line14B-14B.FIG.14Bis a top cross-sectional view of the assembly1200ofFIG.14A, showing an appearance of the second section1400taken at line14B-14B. The second section1400may be taken just above the lower portion of the inner concave surface of the lower matrix material1202, such as just reaching the first concave filter1204. As shown inFIG.14B, a slightly larger (compared toFIG.13B) central region1402may be evident in the second section1400where the assembly1200was cut just at the first concave filter1204. However, the filtered cellular material1206may not have been reached by the second section1400, such that none of the filtered cellular material1206is present in the first section1400. Since no filtered cellular material1206is present in the second section1400, the second section1400may be discarded prior to further histological processing. However, the second section1400may provide an indication to the technician obtaining the second section1400that the filtered cellular material1206may soon be present in subsequent sections.

FIG.15Ais a side cross-sectional view of the assembly1200ofFIG.12, showing a location where a third section1500may be taken at line15B-15B.FIG.15Bis a top cross-sectional view of the assembly1200ofFIG.15A, showing an appearance of the third section1500taken at line15B-15B. The third section1500may be taken just above the lower portion of the first concave filter1204, such as just reaching a lower portion of the filtered cellular material1206within a bottom of the first concave filter1204. As shown inFIG.15B, a disk1502of the filtered cellular material1206may be evident in the third section1500. The third section1500may represent a lowest section that may be suitable for diagnostic review by a pathologist, for example.

FIG.16Ais a side cross-sectional view of the assembly1200ofFIG.12, showing a location where a fourth section1600may be taken at line16B-16B.FIG.16Bis a top cross-sectional view of the assembly1200ofFIG.16A, showing an appearance of the fourth section1600taken at line16B-16B. The fourth section1600may be taken above a lowest layer of filtered cellular material1206within the first concave filter1204. As shown inFIG.16B, a circular ring1602of the filtered cellular material1206may be evident in the fourth section1600.

FIG.17Ais a side cross-sectional view of the assembly1200ofFIG.12, showing a location where a fifth section1700may be taken at line17B-17B.FIG.17Bis a top cross-sectional view of the assembly1200ofFIG.17A, showing an appearance of the fifth section1700taken at line17B-17B. The fifth section1700may be taken through a lower portion of the upper matrix material1210. As shown inFIG.17B, a circular ring1702of the filtered cellular material1206may be evident in the fifth section1700. A central portion of the upper matrix material1210may also be evident in the fifth section1700.

FIG.18Ais a side cross-sectional view of the assembly1200ofFIG.12, showing a location where a sixth section1800may be taken at line18B-18B.FIG.18Bis a top cross-sectional view of the assembly1200ofFIG.18A, showing an appearance of the sixth section1800taken at line18B-18B. The sixth section1800may be taken near a top of the lower matrix material1202. As shown inFIG.18B, a circular ring1802of the filtered cellular material1206may be evident in the sixth section1800. A larger (compared toFIG.17B) central portion of the upper matrix material1210may also be evident in the sixth section1800.

Accordingly, the concave shape of the filtered cellular material1206, due to deposition on the inner surface of the first concave filter1204, may enable a plurality of sequential sections to be obtained from the assembly1200, each of which may include portions of the filtered cellular material1206.

FIG.19is a side cross-sectional view of an assembly1900including a lower matrix material1902, a concave filter1904, and an upper matrix material1906for use with systems for preparing cytological samples, according to at least one embodiment of the present disclosure. A tissue sample1908is illustrated as being positioned between the lower matrix material1902and the upper matrix material1906(e.g., within an inner cavity of the concave filter1904). The tissue sample1908may be a biopsy or brushing, rather than a cellular material obtained from a cellular suspension in a liquid as discussed above. For example, the tissue sample1908may be a biopsy that was removed from an organ of a patient and placed in a liquid. To remove the liquid and form a cell block, the assembly1900may be used in connection with a system for preparing cytological samples, as described herein. For example, the lower matrix material1902may include channels1910through which a negative pressure may be applied to withdraw liquid. The upper matrix material1906may then be applied over the tissue sample1908. For example, the upper matrix material may initially be liquid that is hardened, or the upper matrix material1906may be pre-formed (e.g., pre-gelled). Accordingly, embodiments of the present disclosure may be used to form cell blocks for low-concentration cellular suspensions or bulk tissue samples, such as the tissue sample1908.

FIG.20is an exploded side cross-sectional view of a matrix assembly2000including a lower matrix material2002and an upper matrix material2004, according to at least one embodiment of the present disclosure. As shown inFIG.20, the lower matrix material2002may have a central concave depression2006, and the upper matrix material2004may be shaped and sized to be complementary to (e.g., to fit within) the central concave depression2006.

FIG.21is a side cross-sectional view of a lower matrix material2100, according to at least one embodiment of the present disclosure. As shown inFIG.21, an upper perimeter2102of the lower matrix material2100may be chamfered in cross-section, such as to provide relief to facilitate placement and/or removal of a corresponding upper matrix material.

FIG.22is a side cross-sectional view of a lower matrix material2200, according to at least one additional embodiment of the present disclosure. As shown inFIG.22, an upper perimeter2202of the lower matrix material2200may be rounded in cross section, such as to facilitate handling of the lower matrix material2200.

FIG.23Ais an upper perspective view of a lower matrix material2302, according to at least one further embodiment of the present disclosure.FIG.23Bis an upper perspective view of an exploded matrix assembly2300, including the lower matrix material2302and an upper matrix material2304, according to at least one embodiment of the present disclosure.FIG.23Cis an upper perspective view of the matrix assembly2300ofFIG.23Bwhen the lower matrix material2302and the upper matrix material2304are assembled together, according to at least one embodiment of the present disclosure.FIG.23Dis a top view of the assembled matrix assembly2300ofFIG.23C. As shown inFIGS.23A-23D, in some examples, the lower matrix material2302may include one or more radial recesses2306, such as to facilitate proper placement and/or removal of the upper matrix material2304.

FIG.24is a top view of a prepared tissue sample slide including twelve example sections2402A-2402L of a matrix assembly, according to at least one embodiment of the present disclosure. As shown inFIG.24, the sections2402A-2402L are substantially circular, with a disk or circle of cellular material between or adjacent to portions of upper and lower matrix materials. The cellular material may be simple to locate due to the distinct boundaries between the matrix materials and the portions of the sections2402A-2402L that may contain the cellular material.

Accordingly, disclosed are systems and methods for cytological processing that involve the use of a concave filter to deposit cellular material in a concave configuration. The concave configuration may facilitate obtaining multiple cellular sections for histological review and diagnosis, as described above.

The process parameters and sequence of the steps described and/or illustrated herein are given by way of example only and can be varied as desired. For example, while the steps illustrated and/or described herein may be shown or discussed in a particular order, these steps do not necessarily need to be performed in the order illustrated or discussed. The various exemplary methods described and/or illustrated herein may also omit one or more of the steps described or illustrated herein or include additional steps in addition to those disclosed.

The preceding description has been provided to enable others skilled in the art to best utilize various aspects of the exemplary embodiments disclosed herein. This exemplary description is not intended to be exhaustive or to be limited to any precise form disclosed. Many modifications and variations are possible without departing from the spirit and scope of the instant disclosure. The embodiments disclosed herein should be considered in all respects illustrative and not restrictive. Reference should be made to the appended claims and their equivalents in determining the scope of the instant disclosure.

Unless otherwise noted, the terms “connected to” and “coupled to” (and their derivatives), as used in the specification and claims, are to be construed as permitting both direct and indirect (i.e., via other elements or components) connection. In addition, the terms “a” or “an,” as used in the specification and claims, are to be construed as meaning “at least one of.” Finally, for ease of use, the terms “including” and “having” (and their derivatives), as used in the specification and claims, are interchangeable with and have the same meaning as the word “comprising.”