Table 4:
Concurrence between the surgeons’ confidence in identifying parathyroid and PTeye™ output. (PG, parathyroid gland).
| Surgeon’s confidence in tissue being PG |
In-situ (Final surgeon’s opinion for validation) |
Excised (FSA/ Permanent histology for validation) |
Target tissues tested (n) |
Device Positive: Detection ratio >1.2 (n) |
True Positive: Detection ratio >1.2 (n, %) |
False Positive: Detection ratio >1.2 (n, %) |
Device Negative: Detection ratio <1.2 (n) |
True Negative: Detection ratio <1.2 (n, %) |
False Negative: Detection ratio <1.2 (n, %) |
|---|---|---|---|---|---|---|---|---|---|
| 19 patients – initial set | |||||||||
| High (>75%) | 33 | 21 | 54 | 54 | 52 (96.3) | 2 (3.7) | 0 | 0 (0) | 0 (0) |
| Medium (50-75%) | 1 | 1 | 2 | 2 | 2 (100) | 0 (0) | 0 | 0 (0) | 0 (0) |
| Low (<50%) | 8 | 6 | 14 | 3 | 2 (66.7) | 1 (33.3) | 11 | 11 (100) | 0 (0) |
| Total | 42 | 28 | 70 | 59 | 56 (94.9) | 3 (5.1%) | 11 | 11 (100) | 0 (0) |
| 64 patients – second set | |||||||||
| High (>75%) | 108 | 64 | 172 | 172 | 169 (98.3) | 3 (1.7) | 0 | 0 (0) | 0 (0) |
| Medium (50-75%) | 25 | 0 | 25 | 23 | 22 (95.7) | 1 (4.3) | 2 | 2 (100) | 0 (0) |
| Low (<50%) | 62 | 7 | 69 | 18 | 6 (33.3) | 12 (66.7) | 51 | 51 (100) | 0 (0) |
| Total | 195 | 71 | 266 | 213 | 197 (92.5) | 16 (7.5) | 53 | 53 (100) | 0 (0) |
| 83 patients – overall | |||||||||
| High (>75%) | 141 | 85 | 226 | 226 | 221 (97.8) | 5 (2.2) | 0 | 0 (0) | 0 (0) |
| Medium (50-75%) | 26 | 1 | 27 | 25 | 24 (96) | 1 (4) | 2 | 2 (100) | 0 (0) |
| Low (<50%) | 70 | 13 | 83 | 21 | 8 (38.1) | 13 (61.9) | 62 | 62 (100) | 0 (0) |
| Total | 237 | 99 | 336 | 272 | 253 (93.0) | 19 (7.0) | 64 | 64 (100) | 0 (0) |
Number of true positive, false positive, true negative and false negative (see Table 2) was determined by surgeon’s judgement (for in-situ tissues) or histology (for excised tissues).