J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.29.6.560 on 1 December 1966. Downloaded from

J. Neurol. Neurosurg. Psychiat., 1966, 29, 560

Transpalatal approach to the maxillary division of the trigeminal nerve for alcohol block

C. NORMAN SHEALY1, BENJAMIN KAUFMAN, AND ANTHONY J. TOMARO From the Division ofNeurosurgery, Department of Radiology, Western Reserve University School of Medicine, and School of Dental Surgery, and University Hospitals of Cleveland, Cleveland, Ohio, U.S.A.

Occasionally an old procedure experiences a popular palatine fossa where two branches are contiguous revival; similarly, one subspecialist may chance to with the sphenopalatine ganglion which hangs like a learn an excellent technique from a colleague in grape from the major nerve trunk. The maxillary another field. Recent experience with an approach division at or near this point branches into the to the sphenopalatine ganglion aroused our interest infraorbital nerve and posterior-superior alveolar in a well-known dental technique which was formerly branches (Cunningham, 1937). used by otolaryngologists and is currently used by On a lateral radiograph of the skull, the pterygo- oral surgeons but which has not, to our knowledge, maxillary fissure is easily recognized, marked been standard among neurosurgeons. anteriorly by the posterior wall of the maxillaryguest. Protected by copyright. Sluder (1918) popularized the sphenopalatine sinus and posteriorly by the base of the pterygoid ganglion as the seat of neurological symptoms, in- process of the sphenoid base. Directly medial and cluding 'cluster' or 'Horton's' headaches. Neuro- continuous with the is the surgical publications have refuted this and attacks , marked medially by the upon the ganglion are generally considered ill-ad- orbital and sphenoid processes of the sphenoid and vised now. We do not propose to enter the contro- superiorly by the sphenoid body. The inferior orbital versy as to aetiology or treatment of this entire fissure is continuous medically and superiorly with syndrome, but should like to report some pertinent the pterygopalatine fissure. neuro-anatomical considerations concerning the The pertinent is situated in the maxillary nerve. base of the sphenoid, but because of its plane is not It is of some interest that, despite considerable easily identified radiologically. This has led to the discussion of the sphenopalatine ganglion, little has use of Water's projection to demonstrate the been said of surgical approaches to it. Moreover, foramen. When the lateral approach to the foramen even when an approach is mentioned, it is usually rotundum is used, the Water's view gives good described without noting the proximity of the entire monitoring as to depth of penetration. maxillary division of the fifth cranial nerve (White Oppositethe seconduppermolarthere is a palpable and Sweet, 1955). depression in the palatal mucosa. With slight probing Older otolaryngological texts (Morrison, 1948) here, a no. 24 needle can be inserted into the greater and current dental surgery texts (Thoma, 1963) palatine foramen leading directly through the greater http://jnnp.bmj.com/ describe briefly an anatomical approach with a palatine into the pterygopalatine fossa. The needle to the pterygopalatine fossa which is simple greater palatine foramen can be identified on sub- and guides one directly into the fossa. However, no- mentovertical skull films (Fig. 1). Lesser palatine one has reported the radiological analysis of this foramina, variable in size and number, are situated approach. Simple lateral and anterior-posterior posterior to the greater palatine foramen. If the x-ray films of the skull will immediately confirm the needle is inserted into one of the lesser foramina an position of the needle and allow greater accuracy in easy passage to the pterygopalatine fossa may not be injection of alcohol. found. Almost immediately on emerging from the on September 29, 2021 by , the needle is very close to the NEURO-ANATOMICAL AND RADIOLOGICAL APPROACH foramen rotundum. Two simple x-ray views now The maxillary division of the trigeminal nerve passes suffice to monitor the procedure. A Water's view through the foramen rotundum into the pterygo- will ascertain the relation of the needle to the fora- "Present address: Gundersen Clinic, La Crosse, Wisconsin 54601, men rotundum and a lateral view will give the exact U.S.A. degree of penetration into the pterygopalatine fossa. 560 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.29.6.560 on 1 December 1966. Downloaded from Transpalatal approach to the maxillary division of the trigeminal nerve for alcohol block 561

FIG. 3. guest. Protected by copyright.

FIG. 1. Submentovertical view ofa skull. The arrowpoints to the greater palatine foramen. Immediately posteriorly is a smaller lesser palatine foramen. FIG. 2a. A lateral view of a skull specimen. The upper arrow points to the wire in a pipe cleaner which emerges anteriorly through the foramen rotundum. The lower arrow points to the section ofa paper clip which is inserted through the greater palatine foramen and is in the inferior part ofthe pterygopalatine fossa. FIG. 2b. A submentovertical view ofhalfa skullspecimen showing the meeting of the paper clip and the pipe cleaner wire at the foramen rotundum. FIG. 3. Lateral view ofa skull specimen showing that the paper clip has been advanced to the level ofthe optic fora- http://jnnp.bmj.com/ men which is situated immediately below the planum sphenoidale. on September 29, 2021 by

F:IG. 2b. J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.29.6.560 on 1 December 1966. Downloaded from

562 C. Norman Shealy, Benjamin Kaufman, and Anthony J. Tomaro The tip of the needle enters the lower third of the complained of severe rhinorrhoea from the left nostril. fossa as viewed on the lateral radiographs (Figs. 2a Numerous tests for sugar were negative so that we were and 2b). Deeper penetration may be necessary, but convinced that this probably represented unchecked and closer to nasal secretions, perhaps aggravated by some interference also advances the needle higher the with autonomic supply to the nasal mucosa. Antihista- important superior structures, optic nerves and minesandanticholinergicdrugsfailedtohelp. A temporary extraocular nerves (Fig. 3). The course of the optic block of the left sphenopalatine ganglion with xylocaine nerve can be identified either by considering the bony gave transient dryness of the left nose. or by relating the portion of the optic On 12 December 1964 the region of the left spheno- canal to the planum sphenoidale. Since the needle is palatine ganglion visible radiologically was injected with in a narrow bony canal, its course is fixed in two 1 ml. absolute alcohol inserted through a no. 22 needle directions, leaving depth as the only variable. passed through the greater palatine foramen into the Actually, depth of not more than 2 or 3 mm. into this pterygopalatine fossa (Figs. 4a and 4b). After this procedure there was satisfactory dryness of fossa should suffice and this will avoid injury to the the left nose for six months, with gradual return of important optic and extraocular nerves. secretions over the next two months. We have found that a lateral view of the skull identifies exactly the position of the needle tip and One of us (A.J.T.) has used this approach for a establishes whether the needle is still in the greater number of years to block the maxillary division of the palatine canal or has entered the inferior pterygo- trigeminal nerve, with excellent results. Recently we palatine fossa, the ideal area for alchohol injection. have easily performed by this route a maxillary block In the traditional lateral approach, a Water's in a patient with trigeminal neuralgia. view is not necessary with transpalatine approach.

CASE REPORT DISCUSSION guest. Protected by copyright. A brief r6sume is given here of the patient who aroused Eagle (1942) gives a long discussion of sphenopala- our interest in the procedure described. tine ganglion neuralgia; mostly he treated this with J.M. (U.H. NO. 744-916) This 24-year-old housewife un- cocaine placed behind the middle nasal turbinate. derwent successful removal of a large neurinoma of the He mentions alcohol injections into the ganglion via left gasserian ganglion in 1962. Afterwards she had total this route in five patients, but says the procedure 'is palsies of the left cranial nerves Ill, V, and VI and she not without danger'. http://jnnp.bmj.com/ on September 29, 2021 by

FIG. 4a. (Patient J.M.) Lateral view of skull. A no. 22 FIG. 4b. Water's projection showing course ofthe needle. needle is seen traversing the greater palatine foramen. The The rightforamen rotundum is seen and the depth relation- tip of the needle is touching the sphenoid bone and pene- ship ofthe tip ofthe needle to the unvisualized leftforamen tration is in the lowerpart ofthe pterygopalatinefossa and rotundum can be appreciated. However, since the needle has well below the optic nerve. This penetration is deeper than traversed a small canal, it is obvious that the lateral view is necessary for initial injection. the critical one. J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.29.6.560 on 1 December 1966. Downloaded from

Transpalatal approach to the maxillary division ofthe trigeminal nervefor akohol block 563 Sluder (1918) recommended alcohol injection deeper penetration to the nearby superior orbital into the ganglion, but mentions the possibility of fissure. haemorrhage when this is done through the nose. The 'traditional' lateral approach was developed, As late as 1948 Morrison described alcohol injection according to White and Sweet (1955), by Levy and of the sphenopalatine ganglion through the 'pos- Bandow and introduced into the U.S.A. by Patrick. terior palatine canal' (Sluder, 1918). Two textbooks Although it offers a good chance for success in ex- (Boies, Hilger and Priest, 1964; DeWeese and perienced hands, many failures have been reported. Saunders, 1964) do not describe this technique. The technique described above may prove useful as a Cushing (1920), in his first paper on trigeminal simplified approach which can be controlled. neuralgia, refers to 'extracranial severance' of the maxillary nerve which is bound to occur with exci- SUMMARY sion of Meckel's ganglion; he considered injection of the ganglion intranasally a hazardous procedure. An accurate, well-controlled and x-ray-monitored He mentions removal of Meckel's ganglion together approach to the maxillary nerve is described. It has with the maxillary division, achieved by enlarging long been known to dental surgeons, although pre- the foramen rotundum through a typical subtem- viously radiological monitoring has not been re- poral approach. He does mention a 'transnasal ported. This should eliminate some complications injection of Meckel's ganglion, with resulting numb- of second division trigeminal injections and we ness of the right palate and cheek' for one year. present this paper to acquaint others with the pos- For alcohol injection, neurosurgeons have most sibilities of such an approach. commonly approached the maxillary division intro- REFERENCES ducing a needle percutaneously through a lateral guest. Protected by copyright. approach into the pterygopalatine (pterygomaxil- Boies, L. R., Hilger, J. A., and Priest, R. E. (1964). Fundamentals of lary) fossa as described by White and Sweet (1955). Otolaryngology. 4th ed. W. B. Saunders, Philadelphia. Cunningham's Textbook ofAnatomy. (1937). Edited by J. C. Brash and This is usually done as a relatively blind approach E. B. Jamieson. 7th ed. p. 153. Oxford UniversityPress, London. with dependence upon symptomatic spread of pain Cushing, H. (1920). The Major Trigeminal Neuralgias and Their Surgical Treatment Based on Experiences with 332 Gasserian when the nerve or one of its branches is encountered Operations. Amer. J. med. Sci. 160, 157-184. by the needle. White and Sweet recommend a DeWeese, D. D., and Saunders, W. H. (1964). Textbook of Otolaryngo- Water's x-ray view to see the foramen rotundum logy. 2nd ed. C. V. Mosby, St. Louis. Eagle, W. W. (1942). Sphenopalatine Ganglion Neuralgia. Arch. when there is difficulty encountering the nerve. Al- Otolaryng, 35, 66-84. though largely successful, this traditional approach Morrison, W. W. (1948). In Diseases of the Ear, Nose and Throat. Appleton-Century-Crofts, New York. does not allow exact radiological localization of the Sluder, G. (1918). Concerning Some Headaches and Eye Disorders of needle tip since only one view is employed and it is Nasal Origin. C. V. Mosby, St. Louis. Thoma, K. H. (1963). Oral Surgery. 4th ed. C. V. Mosby, St. Louis. quite possible that some of the reported ocular White, J. C., and Sweet, W. H. (1955). Pain-Its Mechanisms and palsies from injection of alcohol are due to slightly Neurosurgical Control. Thomas, Springfield, Illinois. http://jnnp.bmj.com/ on September 29, 2021 by