**7.6.3 Distal paravertebral block (Magda, Cakala, or Cornell technique)**

Indication is the same as the proximal paravertebral block.

The dorsal and ventral rami of the spinal nerves T13, L1 and L2 are desensitized at the distal ends of L-1, L-2 and L-4. A 7.5-cm, 18-gauge needle is inserted ventral to the tips of the

Local Anesthesia for Husbandry Procedures and Experimental Purposes in Farm Animals 243

Fig. 3. Needle placement sites for cornual nerve block in the goat (Modified from Thurmon

The needle is inserted in front of the base of the ear at the end of the zygomatic arch and is introduced until its point lies at the dorsal border of the arch. 10-15 ml of 2% lidocaine are

Onset of analgesia occurs 10-15 minutes and duration of analgesia is approximately one hour. This block does not produce analgesia of the eye or the lids. In conjunction with topical analgesia (2% lidocaine), it is useful for the removal of foreign bodies from the

This block has no sensory effects but paralyses the muscles of the eyelid. It is used to keep

This is one of the most commonly used techniques to block the motor function of the upper eye lid for ophthalmic surgery, preventing eyelid closure during examination of the eyeball. Retrobulbar nerve block in cattle - Widely used in practice to enucleate the eye. May also be

Peterson's eye block in cattle - Requires more skill and specific anatomic knowledge than retrobulbar nerve block, but involves less risk in damaging surrounding anatomic structure around the eye globe, and less volume requirement reducing potential for systemic toxicity

The point of injection is the notch formed by the supraorbital process cranially, the

An one inch, 14 gauge needle is inserted through a desensitized skin as far anterior and

A 4-5 inch, 18 gauge straight or slightly curved needle is inserted at the point of injection mentioned above in a horizontal and slightly posterior direction until it hits the coronoid

zygomatic arch ventrally, and the coronoid process of the mandible caudally.

cornea and conjunctival sac. Also used, but less frequently, in other species.

the eye open, for example, as an adjunct in ophthalmic surgery.

*et al,* 1996)

injected.

used in many other species.

ventral as possible in the notch.

process of the mandible.

and expense.

respective transverse processes in cows where approximately 10-20 ml of a 2% lidocaine solution are injected in a fan-shaped infiltration pattern.

The needle is completely withdrawn and reinserted dorsal to the transverse process, where the cutaneous branch of the dorsal rami is injected with about 5 ml of the analgesic.

The procedure is repeated for the second and fourth lumbar transverse processes.

10-20 ml 2% lidocaine is used per site and onset and duration of analgesia are similar to the proximal technique.
