Transpalatal greater palatine canal injection: Radioanatomic analysis of where to bend the needle for pediatric sinus surgery.
BACKGROUND
The greater palatine canal (GPC) local injection is used to limit posterior bleeding during sinus surgery in adults. Given the potential for causing iatrogenic damage to the intraorbital contents, this procedure is not commonly used in the pediatric population. No studies have described the anatomic development of the GPC during facial growth. By using age-stratified radioanatomic analysis, the dimensions of the GPC and the clinical implications are described for pediatric patients. An age-stratified radioanatomic study was performed.


METHODS
High-resolution computed tomography measurements included the thickness of the mucosal plane overlying the GPC, the length of the GPC, and the distance between the base of the pterygopalatine fossa (PPF) and the orbital floor. Mean distance and standard deviation were calculated for each age cohort and compared using the one-way ANOVA test.


RESULTS
The GPC length correlated directly with patient age. It varied from 9.14 ± 0.11 mm in the youngest age group (<2 years) to 19.36 ± 2.76 mm in adults (18-64 years). The height of the orbit relative to the hard palate approximated the adult dimensions described in the literature by 12-13 years (49.58 ± 1.72 mm).


CONCLUSIONS
These radioanatomic results suggest that the GPC injection described for adult patients may be safely administered to selected pediatric patients. For patients >12 years old, we recommend bending the needle 45° and inserting it 25 mm. For patients 6-12 years old, the needle should be inserted 20 mm to enter into the PPF. In patients <6 years old, the needle may safely be placed 12 mm into the GPC. Each of these descriptions is based on the minimal distance required to effectively access the PPF but with maximal safety in regard to the orbit. Further clinical correlation of these findings is necessary through future investigation.
Department of Otolaryngology–Head and Neck Surgery, University of North Carolina at Chapel Hill, USA.
Kibwei A
KA
McKinney
Michael E
ME
Stadler
Yu-Tung
YT
Wong
Rupali N
RN
Shah
Austin S
AS
Rose
Carlton J
CJ
Zdanski
Charles S
CS
Ebert
Stephen A
SA
Wheless
Brent A
BA
Senior
Amelia F
AF
Drake
Adam M
AM
Zanation
D000293:Adolescent; D000328:Adult; D001846:Bone Development; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007267:Injections / Q000379:methods*; D008875:Middle Aged; D009339:Needles; D021362:Palate, Hard / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D010256:Paranasal Sinuses / Q000601:surgery*; D014057:Tomography, X-Ray Computed
Cleft Palate Craniofac J. 1992 Mar;29(2):118-28
1571345
Arch Otolaryngol Head Neck Surg. 2008 May;134(5):551-3
18490580
Comput Med Imaging Graph. 2003 Nov-Dec;27(6):481-7
14575781
Laryngoscope. 2006 Jul;116(7):1255-7
16826070
Laryngoscope. 2009 Jun;119(6):1067-75
19418531
Curr Opin Otolaryngol Head Neck Surg. 2005 Feb;13(1):60-6
15654218
J Oral Surg Anesth Hosp Dent Serv. 1961 Mar;19:105-9
13781230
Laryngoscope. 2003 Aug;113(8):1423-4
12897570
Surg Radiol Anat. 2007 Oct;29(7):589-94
17653618
Dent Items Interest. 1950 Dec;72(12):1270-8
14802096
Ann Plast Surg. 1987 Jul;19(1):16-28
3631855
Am J Rhinol. 2006 Nov-Dec;20(6):603-8
17181102
Surg Radiol Anat. 2005 Dec;27(6):511-6
16228112
Curr Opin Otolaryngol Head Neck Surg. 2006 Dec;14(6):393-6
17099346
Laryngoscope. 1988 May;98(5):580-1
3362023