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Evaluating Impact of NIRAF Detection for Identifying Parathyroid Glands During Parathyroidectomy

Evaluating Impact of Near Infrared Autofluorescence (NIRAF) Detection for Identifying Parathyroid Glands During Parathyroidectomy

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04299425
Acronym
NIRAF
Enrollment
160
Registered
2020-03-06
Start date
2020-03-13
Completion date
2023-03-03
Last updated
2024-05-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hypercalcemia, Parathyroid Adenoma, Parathyroid Cancer, Parathyroid Hyperplasia, Parathyroid Neoplasms, Primary Hyperparathyroidism

Keywords

Parathyroidectomy, Intraoperative Parathyroid Identification, Near Infrared Autofluorescence, Persistent Hyperparathyroidism, Persistent Hypercalcemia, Failed Parathyroidectomy, Repeat Parathyroidectomy

Brief summary

This study describes a single center, randomized, single-blinded clinical trial to assess the clinical benefits of the use of near infrared autofluorescence (NIRAF) detection with an FDA-cleared device 'Parathyroid Eye (PTeye)' for identifying parathyroid glands (PGs) during parathyroidectomy (PTx) procedures. It compares risk-benefits and outcomes in PTx patients where NIRAF detection with PTeye for parathyroid identification is either used or not used.

Detailed description

Inability of the surgeon to identify or localize the diseased PG can occur in 5 - 10% of cases resulting in failed parathyroidectomies (PTx). As a result, persistent hyperparathyroidism can occur in these patients resulting in unnecessary repeat surgeries that may be associated with increased morbidity and costs. Ultrasound imaging, 99mTechnetium-sestamibi scintigraphy, and computed tomography (CT) have so far demonstrated variable efficacy in preoperative localization of diseased PGs and may not always correlate well with the surgical field of view as observed intraoperatively. Consequently, most surgeons rely on visual identification of PGs during surgery, whereby the accuracy of PG identification is eventually determined by her/his surgical skill and experience. When in doubt, a surgeon routinely confirms the identity of PG tissue intraoperatively by sending the specimen for frozen section analysis that typically requires a wait time of 20-30 minutes per sample and has additional costs. By easily being able to distinguish parathyroid from other tissues intraoperatively, postsurgical complications and associated costs may be reduced. The unique discovery of near infrared autofluorescence (NIRAF) in parathyroid tissues demonstrated that optical modalities that detect NIRAF can be utilized for non-invasive and label-free identification of parathyroid tissues with an accuracy as high as 97%. Since then, several research groups have explored the feasibility of localizing parathyroid glands using NIRAF detection with reasonable success, resulting in FDA clearance for marketing this optical technique. In this study, we plan to evaluate whether an FDA-cleared device called 'PTeye' (AiBiomed, Santa Barbara, CA) is beneficial or not, for the surgeon and patient during PTx operations. The results of such a study will help us to understand and assess the true impact of optical modalities such as PTeye on (i) improving the quality and efficiency of PTx surgeries and (ii) minimizing risk of postsurgical complications and related expenses. The aim of this prospective single blinded randomized study is to compare 2 groups of patients: PTx patients operated using NIRAF detection technology with PTeye as adjunct tool (NIRAF+) vs. patients operated without the adjunct technology (NIRAF-). The main objective of this study is to assess the benefit of intraoperative use of NIRAF detection technology via PTeye during PTx procedures with regard to PG identification, duration of surgery, number of frozen section analysis performed, number of intraoperative PTH assays sent and incidence of postsurgical complications, if any and history of ER visits or hospitalization or repeat surgeries due to persistent high blood calcium after PTx procedure, compared to standard of care.

Interventions

Near Infrared Autofluorescence (NIRAF) detection technology or 'PTeye' consists of a disposable fiber-optic probe that emits non-ionizing radiation from a NIR 785 nm laser source, and also transmits the resulting tissue NIRAF to a photo detector. The 785 nm laser source emits a maximum power of 20 mW. The device is FDA cleared for clinical use in general surgeries and dermatological use (Class 2 device). After surgeon identifies a potential parathyroid gland in the surgical field, the surgeon places the fiber-optic probe of PTeye on suspect tissue and presses the device foot-pedal to activate tissue NIRAF measurement. Auditory beep at high frequency with a Detection Ratio \> 1.2 is interpreted by device as the suspect tissue being positive for parathyroid.

Sponsors

National Cancer Institute (NCI)
CollaboratorNIH
Vanderbilt-Ingram Cancer Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Subject)

Masking description

Only participants will be masked to the intervention.

Intervention model description

NIRAF detection technology is used as an adjunctive tool for intraoperative parathyroid identification in patients who undergo parathyroidectomy (PTx) in the interventional group. Generic Name of Device: Parathyroid Autofluorescence Detection Device (NIRAF detection technology). The Parathyroid Autofluorescence Detection Device consists of a disposable fiber-optic probe that emits non-ionizing radiation from a near infrared (NIR) 785 nanometer (nm) laser source, and also transmits the resulting tissue NIRAF to a photo-detector. The 785 nm laser source emits a maximum power of 20 milliwatts (mW). The device has an FDA clearance for clinical use in general surgeries and dermatological use (Class 2 device).

Eligibility

Sex/Gender
ALL
Age
18 Years to 99 Years
Healthy volunteers
No

Inclusion criteria

* All primary hyperparathyroidism patients eligible for parathyroidectomy (PTx). Both bilateral and focused mode of PTx will be considered for this study, based on the surgeon's preference. * Re-operative primary hyperparathyroidism patients who have undergone a failed prior PTx.

Exclusion criteria

* Patients with concurrent parathyroid and thyroid disease that require total thyroidectomy. * Patients with secondary or tertiary hyperparathyroidism.

Design outcomes

Primary

MeasureTime frameDescription
Average Number of Parathyroid Glands Identified With High Confidence Per PatientImmediate. During PTx procedure.Average number of parathyroid glands identified (Experimental Group: Glands identified with naked eye + NIRAF; Control Group: Glands identified with naked eye) per patient

Secondary

MeasureTime frameDescription
Number of Frozen Sections Sent for AnalysisImmediate. During PTx procedure.Number of frozen sections sent for analysis during the procedure to confirm potential parathyroid tissue
Duration of Parathyroidectomy (PTx) ProcedureImmediate. During PTx procedure.Duration of PTx procedure - timed from skin incision until the surgeon notifies the anesthesia team to awaken the patient
Number of Participants With Persistent Hyperparathyroidism or Hypercalcemia (Failed Parathyroidectomy).6 months after PTx procedureIf blood calcium with/without parathyroid hormone (PTH) has not normalized at 1st post-operative visit, calcium and/or PTH is subsequently measured as necessary. Patient is defined to have a failed parathyroidectomy if hypercalcemia/hyperparathyroidism (defined as total blood calcium level \> 10.5 mg/dL or 2.6 mmol/L, with/without elevated serum intact PTH \> 65 pg/ml or 6.9 pmol/L) persists at or after the 6th postoperative month.
Number of 'False Positive' Tissues Excised by SurgeonImmediate to 10 days after PTx procedure.Number of tissues that were excised by surgeon assumed to be parathyroid tissue, but is later validated as non-parathyroid tissue (false positive) by histology
Number of Patients Who Have Had Repeat Parathyroidectomy (PTx) ProcedureAt 6-months post-operationNumber of patients with repeat PTx procedure performed after the current procedure.
Number of Participants Stratified by Duration of Hospital Stay0-72 hours after PTx procedure.Number of nights spent for postoperative recovery in the hospital after the surgical procedure.

Countries

United States

Participant flow

Participants by arm

ArmCount
NIRAF Detection Technology +
Parathyroid gland identification will be performed with PTeye using NIRAF detection technology as an adjunctive tool in patients who undergo parathyroidectomy (PTx). NIRAF Detection Technology: Near Infrared Autofluorescence (NIRAF) detection technology or 'PTeye' consists of a disposable fiber-optic probe that emits non-ionizing radiation from a NIR 785 nm laser source, and also transmits the resulting tissue NIRAF to a photo detector. The 785 nm laser source emits a maximum power of 20 mW. The device is FDA cleared for clinical use in general surgeries and dermatological use (Class 2 device). After surgeon identifies a potential parathyroid gland in the surgical field, the surgeon places the fiber-optic probe of PTeye on suspect tissue and presses the device foot-pedal to activate tissue NIRAF measurement. Auditory beep at high frequency with a Detection Ratio \> 1.2 is interpreted by device as the suspect tissue being positive for parathyroid.
80
NIRAF Detection Technology -
Parathyroid gland identification will be performed with the naked eye of the surgeon without using PTeye - NIRAF detection technology in patients who undergo parathyroidectomy (PTx).
80
Total160

Baseline characteristics

CharacteristicNIRAF Detection Technology +NIRAF Detection Technology -Total
Age, Continuous56.8 years
STANDARD_DEVIATION 14.6
59.8 years
STANDARD_DEVIATION 14.4
58.3 years
STANDARD_DEVIATION 14.5
Body Mass Index (BMI)30.77 kg/m2
STANDARD_DEVIATION 7.52
30.94 kg/m2
STANDARD_DEVIATION 7.72
30.85 kg/m2
STANDARD_DEVIATION 7.59
Diagnosis
Lithium-induced HPT
1 Participants0 Participants1 Participants
Diagnosis
MEN1
2 Participants0 Participants2 Participants
Diagnosis
Parathyroid carcinoma
1 Participants0 Participants1 Participants
Diagnosis
Persistent HPT
3 Participants9 Participants12 Participants
Diagnosis
Primary sporadic HPT
72 Participants71 Participants143 Participants
Diagnosis
Recurrent HPT
1 Participants0 Participants1 Participants
Preoperative calcium (pg/dL)11.115 mg/dL
STANDARD_DEVIATION 0.689
11.112 mg/dL
STANDARD_DEVIATION 0.712
11.112 mg/dL
STANDARD_DEVIATION 0.712
Preoperative PTH (pg/mL)152.3 pg/mL
STANDARD_DEVIATION 79.8
163.6 pg/mL
STANDARD_DEVIATION 139
157.9 pg/mL
STANDARD_DEVIATION 112.7
Preoperative vitamin D36.7 mcg
STANDARD_DEVIATION 16
39.6 mcg
STANDARD_DEVIATION 20.5
38.1 mcg
STANDARD_DEVIATION 18.2
Procedure by intention
Bilateral
53 Participants56 Participants109 Participants
Procedure by intention
Focused
27 Participants24 Participants51 Participants
Race/Ethnicity, Customized
Asian
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
Black
5 Participants6 Participants11 Participants
Race/Ethnicity, Customized
Hispanic
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
Non-Hispanic
79 Participants80 Participants159 Participants
Race/Ethnicity, Customized
Other
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
White
73 Participants74 Participants147 Participants
Region of Enrollment
United States
80 participants80 participants160 participants
Sex: Female, Male
Female
62 Participants63 Participants125 Participants
Sex: Female, Male
Male
18 Participants17 Participants35 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 800 / 80
other
Total, other adverse events
0 / 800 / 80
serious
Total, serious adverse events
0 / 800 / 80

Outcome results

Primary

Average Number of Parathyroid Glands Identified With High Confidence Per Patient

Average number of parathyroid glands identified (Experimental Group: Glands identified with naked eye + NIRAF; Control Group: Glands identified with naked eye) per patient

Time frame: Immediate. During PTx procedure.

ArmMeasureValue (MEAN)Dispersion
NIRAF Detection Technology +Average Number of Parathyroid Glands Identified With High Confidence Per Patient3.1 parathyroid glandsStandard Deviation 1.21
NIRAF Detection Technology -Average Number of Parathyroid Glands Identified With High Confidence Per Patient2.7 parathyroid glandsStandard Deviation 1.13
p-value: 0.04t-test, 2 sided
Secondary

Duration of Parathyroidectomy (PTx) Procedure

Duration of PTx procedure - timed from skin incision until the surgeon notifies the anesthesia team to awaken the patient

Time frame: Immediate. During PTx procedure.

ArmMeasureValue (MEAN)Dispersion
NIRAF Detection Technology +Duration of Parathyroidectomy (PTx) Procedure89.3 minutesStandard Deviation 32.6
NIRAF Detection Technology -Duration of Parathyroidectomy (PTx) Procedure95.5 minutesStandard Deviation 39.7
p-value: 0.55t-test, 2 sided
Secondary

Number of 'False Positive' Tissues Excised by Surgeon

Number of tissues that were excised by surgeon assumed to be parathyroid tissue, but is later validated as non-parathyroid tissue (false positive) by histology

Time frame: Immediate to 10 days after PTx procedure.

Population: Only the NIRAF Detection Technology + arm was included in the analysis to calculate the rate of false positives by the device. Since the NIRAF Detection Technology - did not use the device that arm was not included.

ArmMeasureValue (NUMBER)
NIRAF Detection Technology +Number of 'False Positive' Tissues Excised by Surgeon19 false positives
Secondary

Number of Frozen Sections Sent for Analysis

Number of frozen sections sent for analysis during the procedure to confirm potential parathyroid tissue

Time frame: Immediate. During PTx procedure.

ArmMeasureValue (NUMBER)
NIRAF Detection Technology +Number of Frozen Sections Sent for Analysis13 frozen sections
NIRAF Detection Technology -Number of Frozen Sections Sent for Analysis45 frozen sections
Secondary

Number of Participants Stratified by Duration of Hospital Stay

Number of nights spent for postoperative recovery in the hospital after the surgical procedure.

Time frame: 0-72 hours after PTx procedure.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
NIRAF Detection Technology +Number of Participants Stratified by Duration of Hospital StayOvernight14 Participants
NIRAF Detection Technology +Number of Participants Stratified by Duration of Hospital StayDischarged same day64 Participants
NIRAF Detection Technology +Number of Participants Stratified by Duration of Hospital StayAdmitted > 23 hours2 Participants
NIRAF Detection Technology -Number of Participants Stratified by Duration of Hospital StayDischarged same day66 Participants
NIRAF Detection Technology -Number of Participants Stratified by Duration of Hospital StayOvernight14 Participants
NIRAF Detection Technology -Number of Participants Stratified by Duration of Hospital StayAdmitted > 23 hours0 Participants
p-value: 0.36Chi-squared
Secondary

Number of Participants With Persistent Hyperparathyroidism or Hypercalcemia (Failed Parathyroidectomy).

If blood calcium with/without parathyroid hormone (PTH) has not normalized at 1st post-operative visit, calcium and/or PTH is subsequently measured as necessary. Patient is defined to have a failed parathyroidectomy if hypercalcemia/hyperparathyroidism (defined as total blood calcium level \> 10.5 mg/dL or 2.6 mmol/L, with/without elevated serum intact PTH \> 65 pg/ml or 6.9 pmol/L) persists at or after the 6th postoperative month.

Time frame: 6 months after PTx procedure

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
NIRAF Detection Technology +Number of Participants With Persistent Hyperparathyroidism or Hypercalcemia (Failed Parathyroidectomy).0 Participants
NIRAF Detection Technology -Number of Participants With Persistent Hyperparathyroidism or Hypercalcemia (Failed Parathyroidectomy).1 Participants
p-value: 1Chi-squared
Secondary

Number of Patients Who Have Had Repeat Parathyroidectomy (PTx) Procedure

Number of patients with repeat PTx procedure performed after the current procedure.

Time frame: At 6-months post-operation

Population: Nearly all patients attended their first follow-up appointment (5-14 days post-operation), however about 30 patients were lost for long-term follow-up.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
NIRAF Detection Technology +Number of Patients Who Have Had Repeat Parathyroidectomy (PTx) Procedure0 Participants
NIRAF Detection Technology -Number of Patients Who Have Had Repeat Parathyroidectomy (PTx) Procedure1 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026