Lewis T, Jacobsen G, Ozog D. Intrafollicular Orifice Injection Technique for Botulinum Toxin Type A. Arch Dermatol. 2008;144(12):1657-1658. doi:10.1001/archderm.144.12.1657
Botulinum toxin type A (Botox; Allergan Inc, Irvine, California) injection for facial enhancement is the most common cosmetic procedure performed in the United States.1- 3 Patient comfort and pain control is important for patient satisfaction and for patient retention after the cosmetic procedure. The use of preservative-containing isotonic sodium chloride solution (normal saline), topical anesthesia, and cryoanalgesia prior to injection of botulinum toxin type A or B decreases patient discomfort, as does the use of 32-gauge rather than 30-gauge needles.4- 6 Since intrafollicular orifice injection (IFOI) decreases the pain of local anesthesia,7 we extend the technique to the injection of botulinum toxin into the glabellar region. In the present study, we compared the IFOI technique with nonfollicular traditional injection (TI) with regard to patient pain perception.
This prospective, randomized study was limited to female patients with no history of receiving Botox. Exclusion criteria were pregnancy, attempting pregnancy, and/or breastfeeding; known hypersensitivity to ingredients; peripheral motor neuropathic diseases or neuromuscular junctional disorders; and/or taking aminoglycosides (eg, gentamicin), anticholinesterase (eg, neostigmine), or lincosamides (eg, clindamycin). Informed consent was obtained, and the study was performed in accordance with institutional review board approval at Henry Ford Health System.
The Botox from the manufacturer was diluted with 2.5 mL of bacteriostatic, preservative-containing normal saline, 0.9%, resulting in 4 U of Botox per 0.1 mL of solution. One of us (D.O.) injected a total of 12 U of Botox into each patient's glabellar complex. As illustrated in the video), we pinched and held the skin at the injection site before using a 31-gauge BD Ultra-Fine II short needle (BD Consumer Healthcare, Franklin Lakes, New Jersey) with a 0.3-mL insulin syringe to administer the IFOI or TI treatment.
Patients were randomly assigned to start with either IFOI or TI and received a total of 6 injections: 2 into the procerus and 2 each into the right and left corrugator supercilii. Odd-numbered patients started with IFOI, and even-numbered patients with TI. If the procerus initially was treated with IFOI, then the right corrugator would be treated by the TI technique first, and the left corrugator with IFOI. After each set of injections into a location, the patient rated her pain from 1 to 10 and chose the number of the injection that was more painful (1 or 2).
For each site (procerus and bilateral corrugator supercilii), we tested the IFOI to TI pain score ratio against a ratio of 1:1 using the χ2 test of specified proportions. The pain scores from all of the locations simultaneously were evaluated by repeated measures analysis of variance with factors for treatment and location. In the repeated measures analysis, pain scores were logarithm transformed to better conform to the assumption of distributional normality. All P values less than .05 were considered statistically significant.
When directly comparing the 2 injection techniques at each of the 3 locations, we found that statistical significance was achieved in the right corrugator (P = .046) (Table 1). The repeated measures analysis of variance with factors for treatment type and location to evaluate the pain scores from all locations simultaneously detected statistically significant differences among the 3 locations (P = .02) and the 2 treatment techniques (P < .001). The interaction P value indicated that the pain score difference between the 2 treatments was similar within each location. The location P value indicated that there was a statistically significant overall pain score difference among the 3 locations (highest pain scores in the right corrugator, followed by the left corrugator, and lowest in the procerus) (Table 2). The treatment P value indicated that there was a statistically significant overall pain score difference between the 2 treatment techniques, with the TI technique pain scores being higher than the IFOI pain scores.
Our study demonstrates a decrease in pain with the IFOI injection technique in a location with prominent follicular openings. We hypothesize that patients with large, prominent pores will have the most pain reduction with the IFOI technique; however, we are unable to support this hypothesis because we did not stratify our patients based on pore size. It is possible that the decrease in pain when the follicular orifice is cannulated is due to decreased depth of dermal penetration. We also demonstrated that injection of the procerus, regardless of technique, is significantly less painful than injection into the corrugators.
A limitation to our study is that a single unblinded physician administered the injections. Nonverbal cues may have been unintentionally communicated by the physician. It is also possible that the physician grasped the skin more firmly during IFOI injections, which may have acted as a greater distracter to the patient and decreased pain sensation. Repetitive use of the same needle may result in some dulling of the tip. Finally, small variations in injection aliquot size could result in variation in tissue distortion.
The IFOI technique is easily implemented because it requires no additional time or effort by the patient or office staff. It may also help decrease patient apprehension, increase overall patient satisfaction, and improve patient retention.
Correspondence: Dr Ozog, Department of Dermatology, Henry Ford Health System, 3031 W Grand Blvd, Ste 800, Detroit, MI (firstname.lastname@example.org).
Accepted for Publication: July 6, 2008.
Author Contributions: Drs Lewis and Ozog and Mr Jacobsen had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Lewis and Ozog. Acquisition of data: Lewis and Ozog. Analysis and interpretation of data: Lewis, Jacobsen, and Ozog. Drafting of the manuscript: Lewis, Jacobsen, and Ozog. Critical revision of the manuscript for important intellectual content: Lewis and Ozog. Statistical analysis: Jacobsen. Obtained funding: Ozog. Administrative, technical, and material support: Lewis and Ozog. Study supervision: Ozog.
Financial Disclosure: None reported
Funding/Support: The Henry W. Lim Lectureship and Educational Fund provided financial support for the purchase of the Botox used in the study.
Previous Presentation: This study was presented as a poster at the 2007 American Academy of Dermatology Annual Meeting; February 2-6, 2007; Washington, DC.
Additional Contributions: Henry W. Lim, MD, supported the work throughout this project; Joseph Madej produced the video presentation; and Jennifer Janiga, MD, participated as the video subject.