A patient is given HPD 72 hours prior to the investigation of a malignant tumour

Question

A patient is given HPD 72 hours prior to the investigation of a malignant tumour. Describe and draw an endoscopic system for the diagnosis and treatment of the malignant tumour. Give some details (five (5) lines) relating to the diagnosis using the above method. i) Discuss how it is done, (three (3) lines) ii) What laser in the figure is useful to achieve the tumour diagnosis? (one (1) short line) ii) What kind of fiber would you use to transmit both red and UV radiations? Why? (one (1) line) Give some details (three (3) to four (4) lines) relating to the therapy of the malignant tumour using this method. i) Discuss how it is done, (three (3) lines or so) ii) What laser in the figure is useful to achieve therapy of the tumour?

Explanation / Answer

it is called endoscopic photodynamic therapy. The HPD hematoporphyrin derivative is a light sensitive dye injected into the body to detect the tumours and generally before 72 hours and will be subjected to the light coming from a laser at 630nm using an argon dye laser system. here the lesions are subjected to the energy dose 90-150 J/cm2. The silica-silicone dye is used to transmit the laser thru biopsy channel of the endoscope. it is generally given to lung and GI tumours. no major complications were reported by this method. The method has a photochemical reaction between light, molecular oxygen and photosensitizer molecule result in ROS production which is delivered locally to the tumour and results in the destruction of the tumour.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.