An Ultrasound-Guided Injection of Therapeutic Drugs into Human Salivary Glands

Begin by having the patient, with their mouth open, lie on an ultrasound table, in a supine position with the neck extended.

Disinfect and anesthetize the areas surrounding the enlarged submandibular gland and parotid gland.

Apply ultrasound gel for enhanced ultrasound wave transmission.

Place a high-frequency ultrasound probe under the mandible between the neck muscles to visualize the submandibular gland, which appears dark compared to surrounding tissues.

Guided by real-time visualization of the needle position, which appears as a bright line, inject the therapeutic drug accurately into the upper and lower areas of the submandibular gland, facilitating widespread drug diffusion within the tissue.

Next, place the probe under the ear canal to visualize the parotid gland, which appears darker than the surrounding tissues.

Identify the upper and lower access sites for the parotid gland injection. With real-time ultrasound guidance, inject the drug into gland quadrants to distribute it throughout the tissue.

Following injection, allow the patient to recover and assess for any possible adverse effects.

Begin by placing the patient on the ultrasound table in the supine position with their neck extended. Use antiseptic to disinfect the skin in the area of the parotid and the submandibular glands. Next, turn on the ultrasound systems, and press the Start/End button to begin the exam.

Press the Probe button to select the high-frequency probe, then press the Patient button to enter the patient's first name and last name. Press the Depth button and specify the depth of view to 5 centimeters. Following that, press the Focus button to select the maximum detail of 2 centimeters.

Next, place the transducer under the mandible between the anterior and posterior bellies of the digastric muscle in order to visualize the submandibular gland, which should appear as a hypoechoic area, with homogeneous echo texture compared to the surrounding tissues.

Finally, place the transducer below the external acoustic meatus to visualize the parotid gland, which should also appear as a hypoechoic area with homogeneous echo texture compared to the surrounding tissues. For the injection, acquire a 22-gauge needle and use a lateral short-axis approach at the widest gland diameter to access the submandibular gland.

Inject 25 IU of botulinum toxin or BoNT-A into the upper submandibular quadrant. After the injection, slightly retract the needle, and change the direction of the needle tip towards the lower submandibular quadrant. Inject another 25 IU of BoNT-A for a total of 50 IU in each submandibular gland.

Dab any bleeding with sterile gauze for 1 to 2 minutes. Next, for the parotid gland injection, identify two access sites, midway between the external auditory canal and the mandible angle where one is in the cranial part of the gland and the other in the caudal part of the gland.

Then, use the upper access site in the cranial part of the gland to inject 18 to 19 IU of BoNT-A into the medial cranial quadrant. After the injection, slightly retract the needle without leaving the side of the cranial part of the gland, and change the direction of the needle tip towards the lateral cranial quadrant. Inject another 18 to 19 IU of BoNT-A.

Next, use the lower access site in the caudal part of the gland to inject 18 and 19 IU of bonta into the medial caudal quadrant. Then, slightly retract the needle without leaving the side of the caudal part of the gland, and change the direction of the needle tip towards the lateral caudal quadrant. Inject a final 18 to 19 IU of BoNT-A for a total of 75 IU BoNT-A in the four prodded parotid areas. Finally, dab any residual bleeding with sterile gauze. Keep the patient for one hour to monitor any potential adverse events.