Hypercalcemia, Parathyroid Adenoma, Parathyroid Cancer, Parathyroid Hyperplasia, Parathyroid Neoplasms, Primary Hyperparathyroidism
Conditions
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
Study design
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
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
| Measure | Time frame | Description |
|---|---|---|
| Average Number of Parathyroid Glands Identified With High Confidence Per Patient | Immediate. 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
| Measure | Time frame | Description |
|---|---|---|
| Number of Frozen Sections Sent for Analysis | Immediate. During PTx procedure. | Number of frozen sections sent for analysis during the procedure to confirm potential parathyroid tissue |
| Duration of Parathyroidectomy (PTx) Procedure | Immediate. 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 procedure | 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. |
| Number of 'False Positive' Tissues Excised by Surgeon | Immediate 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) Procedure | At 6-months post-operation | Number of patients with repeat PTx procedure performed after the current procedure. |
| Number of Participants Stratified by Duration of Hospital Stay | 0-72 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
| Arm | Count |
|---|---|
| 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 |
| Total | 160 |
Baseline characteristics
| Characteristic | NIRAF Detection Technology + | NIRAF Detection Technology - | Total |
|---|---|---|---|
| Age, Continuous | 56.8 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 Participants | 0 Participants | 1 Participants |
| Diagnosis MEN1 | 2 Participants | 0 Participants | 2 Participants |
| Diagnosis Parathyroid carcinoma | 1 Participants | 0 Participants | 1 Participants |
| Diagnosis Persistent HPT | 3 Participants | 9 Participants | 12 Participants |
| Diagnosis Primary sporadic HPT | 72 Participants | 71 Participants | 143 Participants |
| Diagnosis Recurrent HPT | 1 Participants | 0 Participants | 1 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 D | 36.7 mcg STANDARD_DEVIATION 16 | 39.6 mcg STANDARD_DEVIATION 20.5 | 38.1 mcg STANDARD_DEVIATION 18.2 |
| Procedure by intention Bilateral | 53 Participants | 56 Participants | 109 Participants |
| Procedure by intention Focused | 27 Participants | 24 Participants | 51 Participants |
| Race/Ethnicity, Customized Asian | 1 Participants | 0 Participants | 1 Participants |
| Race/Ethnicity, Customized Black | 5 Participants | 6 Participants | 11 Participants |
| Race/Ethnicity, Customized Hispanic | 1 Participants | 0 Participants | 1 Participants |
| Race/Ethnicity, Customized Non-Hispanic | 79 Participants | 80 Participants | 159 Participants |
| Race/Ethnicity, Customized Other | 1 Participants | 0 Participants | 1 Participants |
| Race/Ethnicity, Customized White | 73 Participants | 74 Participants | 147 Participants |
| Region of Enrollment United States | 80 participants | 80 participants | 160 participants |
| Sex: Female, Male Female | 62 Participants | 63 Participants | 125 Participants |
| Sex: Female, Male Male | 18 Participants | 17 Participants | 35 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 80 | 0 / 80 |
| other Total, other adverse events | 0 / 80 | 0 / 80 |
| serious Total, serious adverse events | 0 / 80 | 0 / 80 |
Outcome results
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.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| NIRAF Detection Technology + | Average Number of Parathyroid Glands Identified With High Confidence Per Patient | 3.1 parathyroid glands | Standard Deviation 1.21 |
| NIRAF Detection Technology - | Average Number of Parathyroid Glands Identified With High Confidence Per Patient | 2.7 parathyroid glands | Standard Deviation 1.13 |
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.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| NIRAF Detection Technology + | Duration of Parathyroidectomy (PTx) Procedure | 89.3 minutes | Standard Deviation 32.6 |
| NIRAF Detection Technology - | Duration of Parathyroidectomy (PTx) Procedure | 95.5 minutes | Standard Deviation 39.7 |
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.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| NIRAF Detection Technology + | Number of 'False Positive' Tissues Excised by Surgeon | 19 false positives |
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.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| NIRAF Detection Technology + | Number of Frozen Sections Sent for Analysis | 13 frozen sections |
| NIRAF Detection Technology - | Number of Frozen Sections Sent for Analysis | 45 frozen sections |
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.
| Arm | Measure | Category | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| NIRAF Detection Technology + | Number of Participants Stratified by Duration of Hospital Stay | Overnight | 14 Participants |
| NIRAF Detection Technology + | Number of Participants Stratified by Duration of Hospital Stay | Discharged same day | 64 Participants |
| NIRAF Detection Technology + | Number of Participants Stratified by Duration of Hospital Stay | Admitted > 23 hours | 2 Participants |
| NIRAF Detection Technology - | Number of Participants Stratified by Duration of Hospital Stay | Discharged same day | 66 Participants |
| NIRAF Detection Technology - | Number of Participants Stratified by Duration of Hospital Stay | Overnight | 14 Participants |
| NIRAF Detection Technology - | Number of Participants Stratified by Duration of Hospital Stay | Admitted > 23 hours | 0 Participants |
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
| Arm | Measure | Value (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 |
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.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| NIRAF Detection Technology + | Number of Patients Who Have Had Repeat Parathyroidectomy (PTx) Procedure | 0 Participants |
| NIRAF Detection Technology - | Number of Patients Who Have Had Repeat Parathyroidectomy (PTx) Procedure | 1 Participants |