Correlation coefficient of 0.972, standard deviation of 1.44
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Clinical study of 198 patients (8 US sites, 1 Sweden site)
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Indications for Use
The intended use of the CRIT-SCAN II Monitor is as a hematocrit-measuring device. NOTE: The CRIT-SCAN II is not for pediatric use.
Device Story
CRIT-SCAN II is a non-invasive, transcutaneous hematocrit monitor. Device uses optoelectronics to measure light absorption and scattering through a patient's finger. Finger is placed in a custom cuff that inflates to ensure perfusion. Device operates in clinical settings (e.g., intensive care, dialysis units) to provide hematocrit readings in under 30 seconds. Eliminates need for finger-stick blood sampling, reducing discomfort and risk of communicable disease. Healthcare providers use output to assess patient's anemic state and expedite treatment. Patient must remain still during 1-2 minute data acquisition. Device is intended for adult use only.
Clinical Evidence
Clinical study of 198 subjects (105 male, 93 female; ages 17-79) across 9 sites. Subjects included 74 dialysis patients and 124 healthy individuals. Data compared CRIT-SCAN II readings to Coulter Counter measurements. Regression analysis showed a correlation coefficient of 0.972 with a standard deviation of 1.44. No dependence on age, sex, pigmentation, finger size, or health status noted.
Technological Characteristics
Non-invasive electromechanical/optical hematocrit monitor. Uses optoelectronics to measure light absorption and scattering. Features custom cuff for finger perfusion. Standalone device. No specific materials or software architecture standards provided.
Indications for Use
Indicated for non-invasive hematocrit measurement in patients aged 17 and older to determine anemic state. Not for pediatric use.
Regulatory Classification
Identification
An automated hematocrit instrument is a fully automated or semi-automated device which may or may not be part of a larger system. This device measures the packed red cell volume of a blood sample to distinguish normal from abnormal states, such as anemia and erythrocytosis (an increase in the number of red cells).
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# MAY 2 7 1999
K983555-1
# 510(k) SUMMARY
### Submitter's Information 1.
Matthew L. Haynie In-Line Diagnostics (IDC) 117 West 200 South Farmington, UT 84025 Tel: 801-451-9000 Fax: 801-451-9007
## 510(k) Summary Prepared By:
Same as above
#### Date 510(k) Summary Prepared: 2.
September 28th, 1998 (updated May 25th, 1999 as per Dr. Charles C. Ho's suggestion)
### Name of Device: 3.
CRIT-SCAN II Monitor:
## Common Name:
Non-invasive (transcutaneous) hematocrit monitor
## Classification Name:
Physicians Office Lab/Blood Donor Facility Accessory
## 4. Identification of legally marketed device which the submitter claims equivalence:
The CRIT-SCAN II is an improvement to its predecessor, the CRIT-SCAN, which received 510 (K) approval in April 1992 (see # K910077). In the CRIT-SCAN 510 (K) submission, IDC claimed an accuracy level of ± 3 HCT% as compared to the microcentrifugation method of hematocrit measurement. For the CRIT-SCAN II, IDC claims an accuracy level of 1.5 HCT% as compared to Coulter Counter method of hematocrit measurement.
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NOTE: All data collected with the CRIT-SCAN II was compared to a Coulter Counter, a highly accepted method of hematocrit measurement in the blood processing industry. Due to the nature of the study, it made more sense to compare the CRIT-SCAN II to a Coulter Counter rather than its predicate device, the CRT-SCAN. This is due to the time restraints of taking measurements from a majority of patients whose hematocrit was changing at a quick rate (i.e. dialysis patients).
### Description of the Subject Devices: ട.
The CRIT-SCAN II consists of state-of-the-art optoelectronics which, when combined with custom software, has the ability to measure hematocrit transcutaneously (i.e. through a patient's middle finger or index finger). The patient's finger is placed into a custom designed cuff which, when filled with air, creates the necessary perfusion for the optoelectronics to take a hematocrit reading.
### Intended use of the Subject Device: 6.
The intended use of the CRIT-SCAN II Monitor is as a continuous, non-invasive hematocrit-measuring device whereby a physician could use the information to determine the anemic state of the patient. A patient would place one of his or her fingers in a custom designed sensor assembly. In less than 30 seconds, the CRIT-SCAN II provides a hematocrit reading, thus providing the physician with an accurate value concerning the patient's anemic state.
Use of the CRIT-SCAN II would eliminate the need for a "finger stick", which is commonly used to get a sufficient sample of blood for hematocrit determination. Eliminating the need for a "finger stick" prevents all the potential problems associated with needles, communicable blood diseases and patient discomfort.
It is also anticipated that the CRIT-SCAN II would be beneficial in an intensive care environment where being able to non-invasively measure a patient's hematocrit within one minute could expedite proper treatment.
NOTE: The CRIT-SCAN II is not for pediatric use.
## 7. Technological Characteristics of the Subject Devices:
The CRIT-SCAN II is a non-invasive electromechanical/optical hematocritmeasuring device. The optical light emitted by the device is scattered by the blood and then detected the device. The hematocrit measurement is a function of how the light is absorbed and scattered.
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## Discussion of Clinical Tests Performed: 8.
Between December 11th, 1997 and September 10th, 1998, IDC gathered data on 198 patients. The data was gathered during 9 separate studies conducted in the United States (8) and Sweden (1). All measurements taken with the CRIT-SCAN II were taken non-invasively and no intervention took place based on the readings of the CRIT-SCAN II. All subjects were required to complete a consent form since a blood sample was to be drawn. The following is a brief description of the method used to gather the data.
- Once the subject's age, gender, pigmentation and finger size were a. recorded, the CRIT-SCAN II's measuring source was placed onto the subject's finger with the optoelectronics placed against the "fatty pad" or underside of the finger.
- The instrument was turned ON and the quality of the optical and electrical b. signals was validated.
- If the optical or electrical signal was insufficient (i.e. poor perfusion) the C. subject's hand (including the finger being measured) was rubbed or warmed to increase circulation.
- Once the optical and electrical signals were validated, data was recorded d. by the CRIT-SCAN II Monitor while a blood sample was drawn either from the subject's arm or from the subjects dialysis circuit (if a dialysis patient).
- The blood sample was immediately measured via a cell counter (Coulter e. Counter) as well as a hemoglobin measuring device and the data was recorded.
- f. The data measured by the CRIT-SCAN II was compared to the corresponding cell counter data.
The following is a breakdown of the 198 subjects from which the data points were gathered:
- Sex: Data was gathered on 105 males and 93 females. During the study, a. no hematocrit dependence was noted based on sex.
- b. Age: The youngest subject tested was 17 years old while the oldest subject was 79 years old. IDC did not take any pediatric measurements or any measurements on subjects less than 17 years old. During the study, no hematocrit dependence was noted based on age.
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- Subject Condition: 74 subjects were dialysis patients (i.e. typically with C. lower hematocrits) and 124 subjects were normal (i.e. healthy). During the study, no hematocrit dependence was noted based on the subject's health (i.e. whether or not the subject was a dialysis patient had no effect on the CRIT-SCAN II's accuracy).
- Pigmentation: Although four different ethnic groups were included in the તે. study (Caucasian, African American, Hispanic and Asian), skin pigmentation was used to distinguish the subjects being tested. Each subject was given a pigmentation level between 1 and 3. Level 1 indicated light or fair skin and level 3 indicted dark skin. NOTE: the pigmentation level given was based on the pigmentation of the subjects "fatty pad" under the finger tip. Of the 198 subjects, 163 were considered level 1, 26 were considered level 2 and 9 were considered level 3. During the study, no hematocrit dependence was noted based on pigmentation.
- Hematocrit range: The highest hematocrit measured by the e. CRIT SCAN II was 54.1 and the lowest hematocrit measured was a 22.7. During the study, no hematocrit dependence was noted based on hematocrit level (i.e. the CRIT-SCAN II was accurate at low and high hematocrits.
- f. Finger Size: The circumference of every finger was measured prior to placing the finger into the CRIT-SCAN II Monitor. The smallest circumference measurement taken was 1.6 inches and the largest measurement taken was 2.4 inches. During the study, no hematocrit dependence was noted based on finger size.
- User Dependencies: It was noted that the CRIT-SCAN II was sensitive to g. patient movement. Therefore, patients were asked to remain still during the 1 to 2 minute data acquisition phase.
After all 198 data points were gathered, a regression analysis was performed to compare the CRIT-SCAN II data points to the cell counter data points. A comparison of the data resulted in a correlation coefficient of .972 with a standard deviation of 1.44.
### 9. Conclusions
In conclusion, based on comparison with the industry standard Coulter Counter, the subject CRIT-SCAN II has been found to be safe, accurate and effective in its intended use as a non-invasive, transcutaneous hematocrit monitor.
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Image /page/4/Picture/1 description: The image is a black and white logo for the Department of Health & Human Services - USA. The logo features a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is a stylized emblem consisting of three abstract shapes resembling birds in flight, stacked on top of each other.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
MAY 2 7 1999
Mr. Matthew L. Haynie In-Line Diagnostics Corporation P.O. Box 685 117 West 200 South Farmington, UT 84025-0685
K983551 Re : Crit-Scan II Monitor Regulatory Class: II (two) 81 GKF Product Code: March 1, 1999 Dated: Received: March 2, 1999
Dear Mr. Haynie:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in requlatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
{5}------------------------------------------------
Page 2 - Mr. Matthew L. Haynie
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4648. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Thomas J. Callehan
Thomas J. Callahan, Ph.D. Director Division of Cardiovascular, Respiratory, and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number (if known): K983551
Device Name: CRIT-SCAN II MONITOR
Indications for Use:
______________________________________________________________________________________________________________________________________________________________________________
## Section 3 - Intended Use
The intended use of the CRIT-SCAN II Monitor is as a hematocrit-measuring device.
NOTE: The CRIT-SCAN II is not for pediatric use.
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(PLEASE DO NOT WRITE BELOW THIS LINE -- CONTINUE ON ANOTHER PAGE IF NEEDED)
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Concurrence of CDRH, Office of Device Evaluation (ODE)
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Prescription for Use _________________________________________________________________________________________________________________________________________________________ (Per 21 CFR 801.109)
OR
Over the Counter Use__________________________________________________________________________________________________________________________________________________________
(Optional Format 1-2-96)
Arth A. Carlawsh.
(Division Sign-Off) Division of Cardiovascular, Respiratory, and Neurological Devices
510(k) Number ________________________________________________________________________________________________________________________________________________________________
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1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
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Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
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Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
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The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.