Temporal Branch Research Articles

Parapharyngeal space tumor surgery using a modified cervical–parotid approach

Objectives: The cervical approach to parapharyngeal space tumors is blind in cases involving an approach to the vicinity of the skull base from below. We therefore devised a procedure to improve the safety of surgery in the vicinity of the skull base.Methods: With this surgical technique, the temporal branch from the main trunk is first identified, as in the case of parotid gland tumor surgery. We then approach the skull base by entering the posterior aspect of the parotid gland tissue from above the temporal branch and anterior auricular space, allowing clear visual confirmation of the upper part of the tumor. Combining this approach with the conventional cervical approach, which is used for the lower part, the tumor can be separated from top to bottom.Results: We have applied this combined approach in eight patients to date, and post-operative courses have been good, with no cases of facial paralysis.Conclusion: This modified cervical–parotid approach offers a very useful surgical procedure for parapharyngeal space tumors with respect to preservation of the facial nerve and tumor separation in the vicinity of the skull base.

Unilateral retinal vasculopathy in systemic lupus erythematosus

PurposeSystemic lupus erythematosus (SLE) is a multisystem autoimmune disorder affecting multiple organ systems frequently with a relapsing and remitting clinical course. It may have ocular manifestations at posterior pole, cornea, conjunctiva, sclera, uveal tract and optic nerve.SLE is a complex disease with dysregulation of the immune system with defects in the innate and adaptive immune systems.MethodsA 40‐year‐old Spanish woman was diagnosed with SLE 5 years before. At the time she underwent treatment with a tapering dose of oral prednisone (currently 10 mg/day) and hydroxychloroquine because of a relapse only with cutaneous involvement. She came to the emergency department because she noticed a nasal visual field defect and flashes in her right eye. Her best corrected visual acuity (BCVA) was 20/20 in both eyes and slit‐lamp anterior segment examination was unremarkable. Right fundus showed multiple cotton wool spots along the vessels, and some intraretinal haemorrhages in the inferior temporal branch retinal.Right fundus fluorescein angiography revealed an active vasculitis with abnormal vessel permeability and leakage of the dye together with a branch retinal artery occlusion along the inferotemporal arcade without ischemic areas. Her left eye was normal. She was treated with high‐dose steroid (intravenous methylprednisolone 500 mg/day during 3 days). Then, she completed 2 doses of intravenous cyclophosphamide 400 mg and oral prednisone (45 mg/day) and hydroxychloroquine 400 mg/day.ResultsThe following week the fundus examination demonstrated resolution of haemorrhages without neovascularization or cotton wool spots. BCVA remained 20/20 and visual field exam slightly improved.ConclusionsSLE may lead to severe unilateral vasculitis. However, an early diagnosis and aggressive treatment allow the resolution of the disease without many sequelae.

Bleeding after tonsillectomy

Oropharyngeal hemorrhage after tonsillectomy is one of the most common postprocedural ENT emergencies that require immediate attention. Management choices depend on the severity of bleeding, underlying platelet or coagulation disorders, and the patient’s maturity and age. Treatment range from simple observation to an emergent need to both secure the airway and stop the hemorrhage. The workup of the hemorrhagic patient will be discussed from the preoperative to postoperative time period. Surgical techniques in response to various acuity will be discussed to fully elucidate options to control the hemorrhage.

A study of temporal branches of middle cerebral artery in northern India

A study of temporal branches of middle cerebral artery in northern India

A novel treatment for keratitis sicca (Dry eye): Anatomical feasibility study

Chronic dry eye (keratitis sicca) is a significant problem that in certain populations can result in corneal desiccation and the potential for blindness. Therefore, novel treatments for such disorders might decrease patient morbidity. The present study aimed to investigate a potential treatment for chronic dry eye via a cadaveric feasibility study. On 10 cadaveric sides, the parotid gland branch of the auriculotemporal nerve (ATN) was identified and anastomosed to an anterior superficial temporal branch (STb) of this same nerve. The STb was then transposed anteriorly and sutured to the lacrimal gland. The parotid branch of the ATN was easily identified on all sides. The STb of the ATN was easily identified and mobilized on all sides. This latter nerve had adequate length to be moved to the ipsilateral lacrimal gland on all sides. Rerouting parotid gland secretomotor fibers to the superficial branch of the ATN and then moving this branch to the lacrimal gland is a feasible surgical maneuver based on our cadaveric study. Clinical studies are now necessary to show utility of this procedure in patients with chronic dry eye. Clin. Anat. 30:839-843, 2017. © 2017Wiley Periodicals, Inc.

Pure Amnesia

Pure amnesia (amnesic syndrome) is an organic brain syndrome characterized by impairment in episodic memory, with either an anterograde or sometimes retrograde loss of memories. Although episodic memory is impaired, semantic memory, immediate memory, and procedural memory are preserved. The Papez circuit is a network of nerve fibers and nerve centers that starts and ends in the hippocampus travelling by way of the fornix, mammillary bodies, anterior thalamic nuclei, cingulate gyrus, and parahippocampal gyrus. A lesion restricted to this circuit often produces pure amnesia. Regions concerned with the Yakovlev circuit also have an important role in memory. Clinical cases of pure amnesia caused by cerebrovascular disease presented following brain imaging and resulted from various different lesions. The cases identified were predominantly thalamic amnesia and hippocampal amnesia. Thalamic amnesia often resulted from an infarction in the territory of the thalamotuberal artery and paramedian thalamic artery although thalamic hemorrhage in medial portion of thalamus also produced pure amnesia. Hippocampal amnesia usually occurred following an infarction in the temporal branches of posterior cerebral artery. Cases of retrosplenial amnesia caused by subcortical hematoma and infarction in the retrosplenial region are also described. In addition, cases of pure amnesia resulting from an infarction in the fornix, mammillary body hemorrhage, and caudate hemorrhage are also shown.

Gillies temporal incision: an alternate approach to superficial temporal artery biopsy

The main complications of a biopsy of the superficial temporal artery using a standard preauricular approach include scars on the face, weakness of the temporal branch of the facial nerve, and the possible harvest of a disease-free segment of artery. We describe a modification of the Gillies temporal approach, which when placed at the junction of the frontal and parietal branch can be easily modified to harvest either branch. It avoids scarring to the face as it is hidden within the hairline. The incision placed with specific measurements and palpation is easily reproducible. In patients with giant cell arteritis, arterial wall thickening, and narrowing of the lumen, reduced blood flow makes it harder to identify the artery with a Doppler scan. A procedure based on measurements and palpation is therefore likely to yield better results.

Management of Zygomatico-Maxillary Complex Fracture in Military Dental Centre, Dhaka: A Study of 40 Cases

Introduction: Zygomatic bone is closely associated with the maxilla, frontal, temporal bones which are usually involved when a zygomatic bone fracture occurs. The most common causes of these fractures are from the assaults, road traffic accidents and falls. Aesthetic beauties and functions are greatly hampered with the displacement of the fractured fragments.
 Objective: To analyze the aetiology, clinical presentations, surgical intervention and complications associated with zygomatic complex (ZC) fractures in a tertiary level healthcare facility.
 Materials and Methods: This descriptive observational study was carried out in the Oral and Maxillofacial Department, Military Dental Centre, Dhaka during the period of January 2016 to December 2016. Data were obtained from clinical notes and surgical records of the patients using standardized data collection form specifically designed to examine the variables and features of zygomatic complex fractures.
 Results: Road traffic accidents were the leading cause (75%) of zygomatic fractures. The mean operation time was found 99.5±31.2 minutes with a range from 60 to 125 minutes. Open reduction and two-point internal fixation were employed in more than two-third (67.5%) of the cases. Four (10.0%) patients developed postoperative complications; among them 2(5.0%) cases suffered paresis of temporal branch of facial nerve and trismus. Other complications included paraesthesia, ectropion, scar and palpability of plate. Twenty-five (62.5%) patients were found having limited mouth opening preoperatively and postoperative improvement occurred in 21(52.5%). Thirty three (82.5%) patients had facial asymmetry preoperatively and postoperative improvement occurred in 29(72.5%).
 Conclusion: More than two-third of the patients received two point fixations. Only four patients out of forty in this study were found having post operative complications. The functional and Aesthetic outcome was found to be fair in terms of improvement in limitation of mouth opening and correction of facial asymmetry.
 Journal of Armed Forces Medical College Bangladesh Vol.13(1) 2017: 71-74

Anatomy of the Corrugator Muscle.

The aim of this article is to systematically review the anatomy and action of the corrugator muscle. PubMed and Scopus were searched using the terms "corrugator" AND "anatomy." Among the 60 full texts from the 145 relevant abstracts, 34 articles without sufficient content were excluded and 4 articles drawn from the reference lists were added. Among the 30 articles analyzed (721 hemifaces), 28% classified by oblique head and transverse head, and 72% did not. Corrugator originated mostly from the medial supraorbital rim (45%), followed by the medial frontal bone (31%), the medial infraorbital rim (17%), and the upper nasal process (7%). Corrugator extended through the frontalis and orbicularis oculi (41%), only the frontalis (41%), or only the orbicularis oculi (18%). Corrugator ran superolaterally (59%), or laterally (41%). Corrugators inserted mostly to the middle of the eyebrow (57%), or the medial half of the eyebrow (36%), but also to the glabella region (7%). The length of the corrugator ranged 38 to 53 mm. The transverse head (23.38 mm) was longer than the oblique head (19.75 mm). Corrugator was thicker at the medial canthus than at the midpupillary line. Corrugator was innervated by the temporal branch of the facial nerve (66%), the zygomatic branch (17%), or the angular nerve (zygomatic branch and buccal branch, 17%). Supraorbital nerve (60%) or supratrochlear nerve (40%) penetrated the corrugator. The action was depressing, pulling the eyebrow medially (91%), or with medial eyebrow elevation and lateral eyebrow depression (9%). Surgeons must keep this anatomy in mind during surgical procedures.

Repair of the preauricular defects by the superficial temporal artery frontal branch flap and the retrograde retroauricular artery flap

To investigate the feasibility and effectiveness of the superficial temporal artery frontal branch flap combine with the retrograde retroauricular artery flap in repairing the preauricular defects. The superficial temporal artery frontal branch flap with hair is designed for sideburns reconstruction, and the hairless retrograde retroauricular artery flap for repair the hairless area which is between the tragus and the temples.The donor sites were closed directly. From September 2012 to September 2015,9 cases were treated. All flaps survived completely.Surgical incisions and wounds at donor sites and recipient sites healed primarily. All cases were followed up for 6-18 months (10 months on average) and cosmetic results were satisfactory without visible scar. The method of the superficial temporal artery fiontal branch flap combined with the retrograde retroauricular artery flap for the repair of preauricular a large skin defect is simple with less and inconspicious auxiliary incision. The sidebums and hairless area can be simultaneously reconstructed with satisfactory appearance.

Parotid Branches of the Auriculotemporal Nerve: An Anatomical Study With Implications for Frey Syndrome.

The auriculotemporal nerve is one of the many branches of the mandibular division of the trigeminal nerve. Of these, its superficial temporal branch has been most described. Although the parotid branches, secretomotor fibers to the parotid gland, are well known as the cause of Frey syndrome, there have been almost no descriptions of their anatomy. In this study, the authors dissected the parotid branches of the auriculotemporal nerve to elucidate their anatomy. A total of 10 sides from 7 adult and embalmed cadaver heads were used in this study. The specimens were derived from 3 males and 4 females, the age of cadavers at death ranged from 65 to 92 years old. Measurements included their diameter and the distance of their branching point from the main trunk of the auriculotemporal nerve from the middle of the tragus. Three of 10 sides had 2 parotid branches and 7 sides were found to have 1 parotid branch. The vertical distance between middle of the tragus to branching point of the parotid branch ranged from 1.79 to 16.17 mm. The horizontal distance between middle of the tragus to branching point of the parotid branch ranged from 3.03 to 12.62 mm. The diameter of the parotid branch ranged from 0.31 to 0.49 mm. An improved knowledge of the parotid branch of the auriculotemporal nerve might decrease injury to these structures with the potential for postoperative.

Elongated Miofascial Temporal Flap in Comparison with Standard Surgical Procedure of Temporal Muscle Reconstruction.

Introduction:Flap of the temporal muscle (m. temporalis) with its natural position, its mass and its length, compared with other bound and free microvascular flaps, is the method of choice for covering the middle part of the face after the removal of large tumor masses.Material:The study included a sample of 36 patients who were surgically treated due to malignant process at the middle face level with the performed partial, total or bilateral maxillectomy at the Clinic for Maxillofacial Surgery, University Clinical Center in Sarajevo. The sample is divided into three groups.Methods:The usual procedure of lifting the temporal flap in the first group, at the second extension of the coronoid processus. A group of three-elongated myofascial flap, which includes lifting the muscle along with deep temporal branches of maxillary artery with deep temporal fascia, its two layers and associated stem of thesuperficial temporal artery.Results:Statistical analysis of the length indicated that in group III the mean length was 9.83 cm, group II- 8.25, and group I- 6 cm. The longest segmental lobe in group three provides safer work and the length of the lifted lobe with double vascular stem. This provides coverage of defects that cross over the median line of the middle face. The results coincide with the comparative world studies.Conclusion:For large defects at the meddle part of the face that overlap the median line, an extraordinary solution is elongated myofascial flap with double vascular supply, with a larger flap mass and a length of about 9.83 cm.

An optimized abnormal muscle response recording method for intraoperative monitoring of hemifacial spasm and its long-term prognostic value

BackgroundIntraoperative electrophysiological monitoring is used to determine whether decompression is sufficient during microvascular decompression (MVD) for hemifacial spasm (HFS). However, the real offending vessel is sometimes neglected by the neurosurgeons. Here, we reported our experience in using optimized abnormal muscle response (AMR) monitoring and continuous intraoperative monitoring for MVD. MethodsThis study included 2161 HFS patients who underwent MVD using traditional (1023 patients) and optimized (1138 patients) methods. Modified AMR monitoring was adopted in our study, with the zygomatic branch of the facial nerve stimulated and the temporal branch, buccal branch, marginal mandibular branch and cervical branch of the facial nerve detected for AMR. These cases were analyzed retrospectively with emphasis on the postoperative outcomes and intraoperative findings. The therapeutic effect was evaluated at day 1, month 3 and year 1 after operation. ResultsThe relief rate at day 1, month 3 and year 1 after operation for patients who employed optimized AMR recording method was 95.1%, 97.4% and 99.3%, comparing with 92.2%, 95.0% and 97.8% in traditional method. There was significant difference in achieved immediate remission and recovery rate during 12-month follow-up between the two groups (P < 0.05). The modified intraoperative monitoring showed the sensitivity of AMR disappearance to judge the relief at day 1, month 3 and year 1 after HFS operation was 95.7%, 96.3% and 97.3%, respectively; the specificity was 44.6%, 43.3% and 50.0%, respectively; the accuracy was 93.1%, 94.9% and 97.4%, respectively. ConclusionsOur findings demonstrated that the optimized method could improve the positive detection rate of AMR and accuracy of decompression effect prediction. The evaluation for the decompression effect by optimized intraoperative monitoring can increase the immediate remission rate and reduce the delayed recovery rate.

Anatomical study of the superficial temporal branches of the auriculotemporal nerve: Application to surgery and other invasive treatments to the temporal region

The auriculotemporal nerve (ATN) is one of the branches of the mandibular division of the trigeminal nerve, which gives rise to many branches to the retromandibular and temporal regions. Of these, the superficial temporal branch can occasionally be the cause of migraine headaches and auriculotemporal neuralgia. The purpose of this study was to elucidate the anatomy of the superficial temporal branch, which has never been described in detail. A total of 14 sides of cadaveric heads were used for this study. The number of superficial temporal branch was counted, and the horizontal and vertical distances from the middle of the tragus to the branching point were measured. Three of 14 sides had two main trunks, and 11 sides had one main trunk. Each of the duplicated ATN had already branches into two main trunks as they left the retromandibular space. The number of superficial temporal branches ranged from two to seven. The vertical and horizontal distances from the middle of the tragus to the branching point of the superficial temporal branch ranged from 6.19 to 25.65mm and from 3.45 to 11.88mm, respectively. The communicating branches occasionally formed a loop or so-called "ansa," and a double ansa was identified in one case. These data can provide surgeons a better view of the course of these distant branches, so that skin incisions can be better planned.

Cortical branches of the middle cerebral artery in silver fox (Vulpes vulpes)

The study of the vascularization of the cerebrum in silver fox was performed on 80 cerebral hemispheres. It was found that the middle cerebral artery is the strongest vessel supplying blood to the cerebrum. The artery gets divided into ten permanent branches. Two olfactory arteries supply the region of the cerebrum located on the border between the old and the new cortex. The other eight supply the region of the new cortex. The frontal, parietal and temporal branches descended independently from the main trunk of the middle cerebral artery or formed a common trunk. Common trunks for respective groups of branches have been described as the anterior, superior and posterior middle cerebral artery. The alterior olfactory artery in 5% of cases and posterior olfactory artery in 2.5% of cases were independent branches of the middle cerebral artery extending from the rostral cerebral artery.

Abstract: Composite Eye and Periorbital Allotransplantation Flap: A Cadaveric Study

INTRODUCTION: Composite tissue allotransplantation (CTA) has become a strong alternative in the last two decades in parallel with the developments in reconstructive surgery. Especially, reconstruction of the orbit and periorbital soft and bony tissue defects that occurs after traumatic avulsions, burn injuries, and cancer ablative operations is still challenging and it is almost impossible to obtain a satisfying result with conventional techniques. Although there are several allotransplantation models of various facial regions, a cadaver model of eyeball and periorbital tissues(EPT) is not described yet. The aim of this study is to describe a CTA model of eyeball and periorbital tissues on cadavers. 1,2 MATERIAL AND METHODS: The study was performed on 5 fresh human cadavers. The dissection was begun with anterior neck incision and external carotid artery was found. The facial artery and superficial temporal artery branches of external carotid artery were preserved. The pedicle of the skin island of the flap was included these arteries and external jugular vein. Later, a coronal incision was performed and frontal bone was exposed. Following a frontal osteotomy, the frontal lobe of the brain was reached. Frontal lobe was retracted exposing internal jugular vein and ophthalmic artery which is a branch of internal carotid artery. Ophthalmic, oculomotor and abducens nerves were also dissected and included in the flap. Finaly, a “box osteotomy” was performed to add the cavernous sinus in order to increase venous return from the orbit and the dissection was ended. RESULTS: The flap can be raised on the vascular pedicle of common carotid artery with jugular veins. An adequate venous return was observed in the flap after dye injection, and excellent perfusion was observed within CTA including eye. Laser-assisted indocyanine green angiography identified well-defined vascular network without presence of dye leakage. CONCLUSION: In this cadaver study, CTA model including EPT was described for the first time in the literature. The perfusion was confirmed which showed this transplantation is possible in the future. Although harvesting of this flap is difficult to perform, it constitutes a new alternative for reconstruction of periorbital region. We think that dual blood supply may reduce the ischemic process of the retinal ganglion cells. Additional measures should be taken to provide survival of RGC which results in optic nerve regeneration. We think that this model may be a cornerstone for future studies about eyeball transplantation. DISCLOSURE/FINANCIAL SUPPORT:The authors declare none disclosure. REFERENCES: 1. Dubernard JM, Devauchelle B. Face transplantation. Lancet. 2008 Aug 23;372(9639):603–4. 2. Borsuk DE, Christensen J, Dorafshar AH, Bojovic B, Sauerborn PJ, Christy MR, Rodriguez ED. Aesthetic microvascular periorbital subunit reconstruction: beyond primary repair. Plast Reconstr Surg. 2013 Feb;131(2):337–47.

The Deep Temporal Nerve Transfer: An Anatomical Feasibility Study and Implications for Upper Facial Reanimation.

Facial paralysis has a profound impact on the brow, and currently static procedures are the mainstay of treatment. The deep temporal branches of the trigeminal nerve, given their proximity to the brow, may serve as possible donor nerves for both potential innervation of a free muscle transfer in patients with prolonged facial palsy or nerve transfers in acute or subacute palsy. As such, the authors present the detailed surgical anatomy of the deep temporal nerve, assessing feasibility for both functional muscle and nerve transfers, including a proposed surgical technique. Thirty cadaver hemifaces were dissected to establish deep temporal nerve anatomy and perform axonal analysis. Two (53 percent) or three (47 percent) divisions of the deep temporal nerve were noted, with the most consistent division being the middle division (30 of 30 specimens). This division was consistently found approximately 4.1 cm (range, 3.7 to 4.5 cm) anterior to the tragus at the level of the zygomatic arch. For each 1 cm cranial to the arch, the nerve courses approximately 1 mm posteriorly. The number of axons in the proposed temporal branch is 1469 as it emerges from behind the zygomatic arch, 889 at 1 cm, 682 at 2 cm, 534 at 3 cm, 355 at 4 cm, 377 at 5 cm, and 256 at 6 cm. Given its anatomical consistency, and expendability, the middle division of the deep temporal nerve is a viable donor nerve for dynamic upper facial reanimation with either nerve transfer or functional muscle transfer, depending on the length of facial palsy. Therapeutic, V.

Initial Exploration on Temporal Branch of Facial Nerve Function Preservation in Plexiform Neurofibroma Resection.

Background:Large temporal plexiform neurofibroma (PNF) is an irritating problem that causes facial disfigurement. Surgical resection of PNF is the only effective way to remove the tumor as well as to improve the patient's facial appearance. However, temporal branch of the facial nerve (TBFN) in the tumor is prone to be destroyed during PNF removal. Thus, TBFN palsy is the inevitable complication after surgery and might induce other malformation and dysfunction. Therefore, the aim of this study is to reconstruct a nearly normal face contour while preserving the facial nerve function.Purpose:Selective PNF removal technique was designed to protect TBFN during PNF lesions resection in our patients.Methods:From May 2011 to June 2015, the authors had 10 patients who suffered from PNF in the temporal region with facial disfigurement and underwent selective PNF removal to correct the facial disfigurement while preserving TBFN as well.Result:All patients obtained the improvement of facial appearance after surgery. The temporal PNF was removed and the TBFN function successfully maintained. Plexiform neurofibroma recurrence has not been relapsed during 6 to 49 months’ follow-up.Conclusions:In our initial exploration, TBFN function maintenance and facial appearance improvement can be achieved simultaneously by using PNF-selective removal surgery technique.

Motor Innervation of the Corrugator Supercilii Muscle in Relation to Orbital Landmarks: Guidelines for Surgical Denervation.

Precise knowledge of the nerve supply of the corrugator supercilii muscle (CSM) is a prerequisite for performing a selective denervation of the CSM. The authors' goal was to determine the course and variability of the motor nerves of the CSM in relation to fixed orbital landmarks. The facial nerve branches toward the CSM were identified during microscopic dissection of 9 Caucasian formaldehyde-fixed cadaver half-heads. The distances between the branches and defined landmarks were measured. All branches to the transverse head of the CSM ran between 15 and 32 mm superior to the lateral orbital margin. Medially the CSM was supplied by a superficial zygomatic, buccal, or bucco-zygomatic branch, which was much smaller than the temporal branches. This branch ran 4 to 7 mm medial to the medial canthus. This anatomical knowledge can be applied for surgical denervation of the corrugator supercilii muscle. The authors suggest a surgical procedure for corrugator denervation through a blepharoplasty incision.

An anatomy study of temporal layers : the safe space for hyaluronic acid injection

To determine the safe space for hyaluronic acid(HA) injection through anatomy study of temporal layers. 6 fresh and 8 formaldehyde-fixed cadaver heads were dissected. The skin soft-tissue layers of temporal region were incised through the cranial coronal plane and elevated layer by layer. The morphological features of layers were observed and documented, as well as the relationship of the superficial temporal artery (STA),the temporal branch of facial nerve (TFN) and the middle temporal vein(MTV) with corresponding layers. Relevant neasurements of the superficial temporal fat pad (sTFD) were recorded. With reference of cardever dissection, temporal region injection with HA was carried out clinically to confirm the safety and effect. In the temporal region, from surface to the temporal fossa, the layers are skin, subcutaneous tissue, superfiacial temporal fascia (STF),loose areolar tissue, superficial layer of deep temporal fascia(sDTF), sTFD, deep layer of deep temporal fascia (dDTF),deep temporal fat pad (dTFD) and temporalis. The temporal skin is tightly attached with the subcutaneous tissue. The STA runs within the subcutaneous tissue on the STF, whereas the TFN within the areolar tissue was just beneath the STF. The loose areolar tissue is a potential layer space. The DTF splits into two sheets of fascia at the line 1 cm above the upper orbital rim to envelope the sTFD, within which the MTV runs backward. The dTFD is the temporal extension of buccal fat pad. With reference of cadever dissection, the target space of temporal HA injection was beneath the temporalis for the area superior to the MTV, whereas within the sTFD for the area inferior to the MTV.67 cases were completed with good result and no complication. In the upper area of temporal region adjacent to the frontal border, the sub-temporalis space is the safety space for HA injection, while inferior to the middle temporal vein and near the zygoma, the superficial temporal fat pad is the target space for safe HA injection.