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Frequently Asked Questions

Q : How does the Kylon® fabric biopsy work?

Kylon® is woven with long shallow stiff hooks (fenestrated, or cut from loops of stiff nylon thread) onto a nylon fabric pile. The shallow Kylon® hooks do not penetrate the tissue when placed on it with pressure. Instead, when pressed and rotated onto the tissue, the hooks bend back at their junction with the base of the fabric until the hook tips contact the tissue surface, exposing the hook tip to the tissue, "activating" the hooks to remove tissue by applying frictional force to the surface. The de-bonding force creates buckling of the tissue just below the epithelium and excavates fragments identical to curettings (full thickness tissue strips) and fragments similar to small trans-epithelial biopsies.

Q: How do fabric based biopsy devices compare with sharp cutting tools or bristle brushes for biopsies of the exocervix and endocervix?

Exocervical Biopsy with the SoftBiopsy® Gynecological Biopsy Device that employs Kylon®: When pressure is maintained, the hooks rake across the tissue plane frictionally dislodging and shearing tissue strips and fragments from just under the basement membrane, which collect in the base of the fabric. Thus, the unique feature is the shearing away of tissue using frictional de-bonding forces. Multiple fragments or strips can be harvested many of which resemble multiple punch biopsy specimens, depending on the size of the platform the fabric is mounted on (SoftBiopsy® has a circular tip that is just under ½ inch in diameter). Therefore, the surface area covered is many times larger than the average punch biopsy tip. The device is disposable, the fabric functions as a tissue-trap container, and its tip is snapped off at the scored handle to be placed in a fixative vial for transport to the lab. The SoftBiopsy® is commercially sold as a cervical biopsy device and container system, and is registered with the FDA as a Class 1, 510k Exempt gynecologic biopsy device as well as a system for tissue collection, storage and transport.

Stainless Steel Exocervical Gynecological Forceps Biopsy
Conventional colposcopic biopsies essentially crimp and pinch away single small or large fragments from the epithelium in what could be considered a "digging" action. Biopsy with opposing sharp tips usually are associated with varying degrees of discomfort and bleeding depending on the size and depth. Two jaws shear away fragments that are captured within the hollow jaws of the device. The average size fragment can range from 1mm to 5mm, depending on the size of the jaw tip. It is possible to obtain multiple "bites" of tissue from a target area, but each fragment must be removed from the jaw. Thus, the punch biopsy tool might be used multiple times during the procedure, and clinicians should be aware that removing tissue from it repeatedly should be done in a sterile manner.

Flat Spiral Bristle Biopsy Brushes:
Spiral shaped flat stiff brushes such as Spirabrush CX® are ½ inch in diameter. The stiff, thin, needle-like clear nylon brush bristles are loaded into a twisted metal frame and project from the wire. When pressed into tissue, the bristles "drill" into tissue, and with agitation or rotation, they extend into the epithelium to obtain cells and tissue. The specimen is placed in formalin with the brush tip and is transported to the lab. Initially, the Spirabrush CX® was considered a Cytology device, and was FDA cleared as a Class2, 510k Cytology device. It is now marketed for biopsy and is commercially registered for sale as a Class 1, 510k exempt gynecologic biopsy device under the FDA.

Endocervical Curettage employing a Conventional Curette Design:

Endocervical curettage specimens such as those obtained using the Kevorkian curette are obtained by back and forth cutting motions repeated in a radial fashion to scrape or cut away strips or tissue fragments. Because the curette can be repeatedly inserted and removed with force, it can potentially curette the exocervical tissue, and may dislodge some into the hollow of the curette. Most of the tissue remains in the canal following the procedure, usually requiring retrieval of tissue with forceps or a soft linear cytobrush. The specimen is rinsed from the curette or forceps (if used), or squeezed from the cytobrush (if used) using a Telfa® pad, and placed in the jar of fixative. Some of the tissue still remains uncollected in the endocervical canal.

Endocervical Brushing or Curettage with Bristle Brushes:

Although conventional use of the straight bristle brush has been to collect cytology specimens during cervical cytological testing, other brushes have been designed to take cellular specimens for other reasons, such as those used for HPV testing. There are many uses of bristle brushes for endocervical and endometrial biopsy but studies to date show vigorous brushing pose problems with false positive results (1) and similar discomfort levels (2) to conventional curettes.

1. Boardman et al. Obstet Gynecol. 2003 Mar;101(3):426-30.
2. Klam et al. Obstet Gynecol. 2000 Jul;96(1):90-4.

Endocervical Curettage: Soft-ECC® Curette that employs Kylon®
The Soft-ECC® endocervical tissue specimens are obtained by inserting the device tip fabric into the canal parallel to the plane of the canal gently until the fabric is entirely inside the canal. With pressure, the Kylon® hooks bend back at the base and lay flat , exposing the hook tips to the endocervical canal epithelium. This "activates" the fabric hook tips to be able to rotationally and frictionally remove tissue from the canal. If the canal is deep and loose, the face of the fabric must be pressed against the endocervical canal to "activate" the hooks to be able to remove, collect, and store tissue. Instead of the alternating insertion and withdrawal scraping method of the Kevorkian curette (which is noticeable and painful to the patient in many instances), the Soft-ECC® curette is inserted only once and when pressed perpendicularly against the canal and "activated", can be rotated to achieve the shearing and simultaneous collection of most or all of the epithelium excavated during the biopsy. The device is simply gently inserted, pressed against the canal with force equal to tooth brushing (unless there is already a tight fit in the canal), rotated, removed, snapped free at the scored area of the handle, and placed in formalin. There is usually no need to retrieve tissue following removal of the Soft-ECC® device because it is simultaneously collected within the straight rows between the fabric hooks.  The Soft-ECC® is commercially sold as a cervical biopsy device and container system, and is registered with the FDA as a Class 1, 510k Exempt gynecologic biopsy device as well as a tissue removal and container system for tissue collection, storage and trasport.  It is available as as smaller pad device for the short, shallow, or stenotic cervical os as the Soft-ECC-S® as well.
Q: What if the endocervical canal is short, shallow or stenotic?  Is there another version of Soft-ECC® that I can use?

The fabric based endocervical curette and tissue collection, storage, and transport system  is available as as smaller pad device for the short, shallow, or stenotic cervical os as the Soft-ECC-S®.  It is specially designed to employ a shorter pad to prevent inadvertant sampling of the ectocervix.  I should completely recess into the smaller os so that only endocervical (inner and outer endocervix) tissue is obtained, to aid in clinical decision making with more precision.
Q: What if I use the Soft-ECC® instead of the Soft-ECC-S® for the shorter, more shallow cervix and the pad does not completely enter the endocervix?  Are there any risks?  
The Soft-ECC® is the average length of an endocervical canal.  If it is inserted in a shorter/shallow cervix and the pad extends outside the outer endocervix, the hooks can contact the exocervix.  Unless the hooks are pressed down completely, the tips will not excavate biopsy specimens.  Thus, it is unlikey the fabric woud falselly remove tissue from the exocervix if the Kylon® hooks are not splayed flat, exposing the rigid tips; no raking effect shoud occur.  If the device is angled so that the hooks can splay and scrape the exocervix, exocervix tissue can enter the fabric channels.  It is advised that the colposcopist should choose and use the Soft-ECC-S if a stenotic, short, or shallow cervix (common in previously treated patients or peri/post-menopausal patients.

Q: How is a tissue specimen removed from a fabric (Kylon®) based biopsy device and then processed in the lab? How does it compare with other biopsy specimens from alternative methods such as sharp punch biopsy devices, sharp or blunt curettes, soft bristle brushes, or stiff spiral brushes?

Punch biopsy specimens require "unloading" or removal of tissue fragments from the forceps tip with each biopsy. The clinician often reuses the biopsy device and plucks the tissue from the tip between each biopsy with a sharp pick, dropping it in the vial containing fixative such as formalin. Keeping the tip sterile if used multiple times during a colpsocopy procedure is a challenge.  The epithelial fragments are usually full thickness. In the lab, the biopsies are removed from the preserviative vial and then loaded into a cassette for processing.

Endocervical curettage specimens obtained using a sharp curette are usually rinsed into the fixative solution, or pulled away from the curette into Telfa® pads that are dropped into fixative. Once in the lab, the fixative with tissue fragments can be drained into filter paper or a teabag and then loaded into a cassette for processing.

Bristle brush tines are arranged in spiral arrays. If they are soft brushes with tissue trapped between the straight thin, clear bristles, they can simply be squeezed with a forceps or with Telfa® pads with finger pressure to dislodge and capture the tissue for placement in the fixative vial. If they are stiff bristles, a tweezer, knife blade, or forceps can be used to pluck tissue from the bristles. If the brush wire is twisted into a flat spiral, to be effectively cleaned, it must be straightened. Due to the tight spiral, following removal of the brush tip from fixative, when attempting to straighten the wire, histo-technologists customarily wear eye protection in the event that the wire recoils and releases cell and tissue particulates. They also take care to remove any fractured bristles that may have dislodged into the specimen. Many brush bristles are transparent and thin, which can elude detection and serve as artifacts during tissue processing that may affect the quality of the specimen if not identified and removed.

Kylon® fabric hooks are woven tightly into the fabric pile and are arranged in straight rows. After a specimen is taken, the biopsy tip which traps and contains the specimen is snapped off at the scored handle and dropped into a second container; the fixative vial. In the lab, the fabric can be cleaned back into the vial using a small comb or blunt scraper in seconds, or the hooks bent back at the flexible junction with the fabric base using a flat side of a forceps to squeeze the tissue free from the device onto filter paper. The specimen is then placed into the cassette for processing. Kylon® fabric hooks are dense and black in color and in the unlikely event they dislodge when manipulated with comb or forceps in the lab, they can easily be visualized and discarded prior to tissue processing.

Q: Do cervical biopsy forceps and uterine curettes require FDA clearance?

Histologic's Soft-ECC® and SoftBiopsy® are registered with the U.S FDA as a uterine curette and gynecological biopsy forceps, with the product codes "HCY" and "HFB". Spirabrush CX® is also listed with the U.S. FDA as Gynecological Biopsy Forceps, with product code "HFB". Histologic's Soft-ECC®, SoftBiopsy®, as well as, Spirabrush CX® are all Class 1 medical devices that are exempt from 510k FDA premarket notification and clearance status. For more information on proper registration and labeling of medical devices:
The Histologics Kyon® fabric devices have dual purpose and dual registration for clearance for sale.  They also are registered as a Tissue Collection and Transport System because of the dual function of the fabric as a non sterile container, once removed from the body.  The fabric secures the specimen at the device tip, which is snapped free of the handle to be transported to the lab in the preservative vial.

Q: Do cervical cytological spatulas require FDA clearance?

Cervical cytology spatulas are identified by the U.S. FDA under a specific product classification with product code "HHT". This class of product is a Class 2 medical device which does require premarket notification. The identical proprietary name Spirabrush CX® (referenced in the above answer) is listed with the U.S. FDA as a cervical cytology spatula, product code "HHT" which is a Class 2 medical device requiring FDA premarket notification and clearance. Cytology samples prepared in cytology fixative and prepared into cell blocks were the basis for that clearance.

SoftBiopsy® and Soft-ECC® are NOT to be used or considered a cervical spatula cytology device because they dislodge and harvest tissue specimens suitable for histologic analysis. A Class 2 product requires premarket notification and clearance with the FDA. For more information on proper registration and labeling of medical devices:

Q: How are the SoftBiopsy® and Soft-ECC® distributed?

SoftBiopsy® and Soft-ECC® are now available for sale to licensed health care professionals, hospitals, distributors, or laboratories. Clinicians, Support Staff, Hospitals, or Laboratory representatives can reach out to Histologics LLC directly through the Support portal on the Histologics website or by contacting This email address is being protected from spambots. You need JavaScript enabled to view it. for more information on pricing and ordering procedures.

Histologics provides laboratories with access to training and quality support. Laboratories have validated and continue to validate the effectiveness of Fabric Biopsy for clinicians, verifying that the specimens are consistent, diagnostic and abundant.
 This is the subject of some exciting new research. A clinician can request a sample of each device at This email address is being protected from spambots. You need JavaScript enabled to view it., and inquire about purchasing these devices if not available through their laboratory.

Q: What laboratories distribute the SoftBiopsy® and Soft-ECC®?

Please contact Histologics for a list of laboratories that are distributing and re-selling these devices in your area. If your preferred laboratory does not carry the device, they may provide information about Histologics, its products, its pricing and availability. Labs customarily monitor the quality of the tissue samples harvested along with you. For any questions, please have the lab contact Histologics for more information.

Q: Is is safe to use the SoftBiopsy® and Soft-ECC® during a patients menses or unscheduled vaginal bleeding not associated with pregnancy?

During Menses or unscheduled vaginal bleeding: The curette or biopsy device may be used when vaginal bleeding is present when indicated for clinical reasons. Just as with any biopsy, if malignancy is suspected care must be taken to be sure other measures to arrest vaginal bleeding are available when performing any biopsy.

Q: What about tissue sampling during pregnancy?

Curettage is strictly contraindicated in pregnancy. Pregnancy is usually a contraindication for cervical biopsy. Use the exact same judgment and guidelines you would use with other biopsy devices when biopsy is indicated in pregnancy.

Q: What type of samples do SoftBiopsy® and Soft-ECC® take: cytology or histology specimens?

Kylon® based SoftBiopsy® and Soft-ECC® shear and collect intact full thickness epithelial tissue samples and thus are strictly processed as histological specimens.
SoftBiopsy® and Soft-ECC® are registered with the FDA as biopsy devices, not cytology tools.

Q: What fixative is used for SoftBiopsy® and Soft-ECC® tissue samples?

Formalin should be used exclusively (NOT alcohol-based fixatives commonly used for liquid based Pap smears). Alcohol can denature adhesives used in Histologic's devices and should be avoided, or, if preferred, the lab made aware that the fabric pad may disorient from the plastic tip once the specimen arrives in the lab.  Histologics does not sell fixative. Consult the laboratory for their preferred method and fixative.

Q: Do I need to apply local anesthesia to the cervix before performing colposcopic biopsy or curettage?

This is a clinical decision to be made by the clinician and the patient. Colposcopic biopsy and endocervical curettage is rarely performed under local anesthesia. Please refer to the published data regarding fabric based biopsy which discusses and compares the associated pain and bleeding with conventional methods.

Q: Can I use Acetic Acid or Lugol's solution prior to taking a biopsy with SoftBiopsy®?

There is no contraindication to Lugols Iodine or Acetic acid being used for colposcopy when performing any cervical biopsy, including the use of devices that collect tissue with Kylon®.

Q: How do I know I have collected enough tissue with these devices?

The mucoid tissue will be swept into the base below the fabric hook tips after sufficient biopsy and be visible to the clinician. The fabric should be full or nearly full of tissue on the surface area contacting and then de-bonding, collecting and storing the full epithelial fragments and superficial stromal fragments. The full device stores the specimen inside the fixative vial for transport to the laboratory.

Q: What if bleeding occurs during any colposcopic biopsy or curettage including Kylon® fabric tissue collection curettes or biopsy devices?

Bleeding of the exocervix either with any style of biopsy device can occur. Monsels solution or silver nitrate can be applied, just as in any other biopsy procedure. Endocervical bleeding is usually not amenable to the application of either Monsel's solution or Silver Nitrate. Most colposcopic biopsies and curettage bleeding is self limited and brief in duration. The reader is reminded to review the medical literature regarding the likelihood of bleeding with the different styles of devices.
Q:  What about using a cytobrush that customarily is used to remove cytology samples as a biopsy brush to remove tissue samples?  What does the medical research teach us?
This research study is illustrative of the drawback of using cytobrushes as biopsy replacements:
 2005 May-Jun;15(3):489-92.

Can we substitute brush cytology for biopsy in the evaluation of cervical lesions under the guidance of colposcopy?

Brush cytology from colposcopic areas under evaluation was substituted for cerivcal punch biopsy.  40 of 150 (27%) did not retrieve enough tissue to be diagnostic.  Of the remaining 110 cases, brush cytology had a sensitivity of 29% and a specificity of 97%.  The authors concluded that: " colposcopically directed brush cytology is not a safe substitute for biopsy in the evaluation of cervical lesions."

Q:  Do colposcopic cervical biopsies correlate with loop excision or hysterectomy specimens relative to revealing the highest grade of squamous or adenomatous neoplasia present?  Why is excision to rule out invasive cancer in cases with high grade neoplasia on colposcopy so important based on the evidence no matter the biopsy method?                                                                                                                                                                                                 

High grade or Carcinoma-in-situ diagnoses obtained on lesion-targeted or random cervical biopsy using traditional or “baby” punch biopsies, brush devices, or Kylon® Fabric devices require follow up excision (loop excision or cone biopsy) to rule out invasive cancer.  Due to the limitation of the depth of a biopsy (punch biopsies are often small and the jaws rarely extend beyond 3mm in depth, especially “Baby” size devices used to obviate the pain associated with punch biopsy), can be tangential in orientation, or of insufficient depth to clearly document gross invasion).  The trans-epithelial samples obtained with brush or Kylon® devices may have the same limitations rarely extending greater than 3mm in sub-epithelial stromal depth.  Again, it is common, when the biopsy cancer features are not highly anaplastic, to proceed to excision when there is a “full epithelial thickness” neoplastic lesion (CIN 3, AIS) noted on colposcopic biopsy/curettage.


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