Edge Enhancement Optimization in Flexible Endoscopic Images to the Perception of Ear, Nose and Throat Professionals

OBJECTIVES

Digital endoscopes are connected to a video processor that applies various operations to process the image. One of those operations is edge enhancement that sharpens the image. The purpose of this study was to (1) quantify the level of edge enhancement, (2) measure the effect on sharpness and image noise, and (3) study the influence of edge enhancement on image quality perceived by ENT professionals.

METHODS

Three digital flexible endoscopic systems were included. The level of edge enhancement and the influence on sharpness and noise were measured in vitro, while systematically varying the levels of edge enhancement. In vivo images were captured at identical levels of one healthy larynx. Each series of in vivo images was presented to 39 ENT professionals according to a forced pairwise comparison test, to select the image with the best image quality for diagnostic purposes. The numbers of votes were converted to a psychometric scale of just noticeable differences (JND) according to the Thurstone V model.

RESULTS

The maximum level of edge enhancement varied per endoscopic system and ranged from 0.8 to 1.2. Edge enhancement increased sharpness and noise. Images with edge enhancement were unanimously preferred to images without edge enhancement. The quality difference with respect to zero edge enhancement reaches an optimum at levels between 0.7 and 0.9.

CONCLUSION

Edge enhancement has a major impact on sharpness, noise, and the resulting perceived image quality. We conclude that ENT professionals benefit from this video processing and should verify if their equipment is optimally configured.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:842-847, 2024.

Treatment of inoperable or metastatic paragangliomas and pheochromocytomas with peptide receptor radionuclide therapy using 177Lu-DOTATATE

OBJECTIVES

Inoperable or metastatic paragangliomas (PGLs) and malignant pheochromocytomas (PCCs) are rare tumours with limited options for systemic treatment. Aim of this study was to assess the safety and efficacy of the radiolabelled somatostatin analogue (177LutetiumDOTA0-Tyr3)octreotate (177Lu-DOTATATE) for the treatment of PGLs and PCCs.

METHODS

Patients with histologically proven inoperable or malignant PGLs and PCCs treated with 177Lu-DOTATATE at our centre were retrospectively analysed. Patients were treated with up to four cycles of 177Lu-DOTATATE with an intended dose of 7.4 Gb per cycle. Response was assessed with use of RECIST 1.1.

RESULTS

Thirty patients were included: 17 with parasympathetic, 10 with sympathetic PGLs and 3 with PCCs. Grade 3/4 subacute haematotoxicity occurred in 6 (20%) of patients. A reversible subacute adverse event due to cardiac failure following possible catecholamine release occurred in two patients. Best tumour response was partial response in 7 (23%) and stable disease in 20 (67%), whereas 3 (10%) patients had progressive disease. In 20 patients with baseline disease progression, tumour control was observed in 17 (85%); the median progression-free survival was 91 months in patients with parasympathetic PGLs, 13 months in patients with sympathetic PGLs and 10 months in patients with metastatic PCCs.

CONCLUSION

This study suggests that PRRT with 177Lu-DOTATATE is a safe and effective treatment option for patients with inoperable or malignant PGL and PCC.

Respiratory epithelial adenomatoid hamartoma in the nasopharynx

We present a case report of a female patient with complaints of single-sided nasal obstruction. A polypoid structure was seen in the nasopharynx. Histologic examination showed a respiratory epithelial adenomatoid hamartoma – a rare, benign lesion. Therapy consisted of complete excision. In line with previous reports, the lesion did not recur during 13 months of follow up. The clinical and pathological features of this abnormality are discussed.