Supraorbital nerve exits: positional variations and localization relative to surgical landmarks / 대한해부학회지

Significant variations exist in the occurrence, form, and position of supraorbital nerve exits through the frontal bone. Detailed knowledge of the positional variations of supraorbital exits is important to ensure safe and successful regional anesthesia, and to avoid iatrogenic nerve injuries during surgery of the orbitofacial region. Supraorbital nerve exits from 116 sides of 58 dry intact adult skulls (37 male and 21 female) in a Sri Lankan population were examined to determine the morphological features and the precise position in relation to the facial midline, temporal crest of frontal bone, and frontozygomatic suture. A majority of supraorbital nerve exits existed as notches (73.8%) and the rest as foramina (26.2%). Accessory exits were seen in 18.9% skulls. Of the skulls examined, 55.1% displayed bilateral supraorbital notches, 8.6% had bilateral supraorbital foramina, and 36.3% had a notch on one side and a foramen on the contralateral side. In males, the supraorbital nerve exit was located 23.64±3.49 mm laterally from the facial midline, 27.86±2.76 mm medially from the temporal crest of the frontal bone, 28.66±2.56 mm from the frontozygomatic suture, and 2.12±1.07 mm above the supraorbital margin in the case of a foramen, and in females 22.69±3.28 mm laterally from the facial midline, 26.32±3.02 medially from temporal crest of frontal bone, 27.29±3.05 from the frontozygomatic suture, and 2.99±1.49 mm above the supraorbital margin when it existed as a foramen. The observations made in this study will be useful when planning a supraorbital nerve block and surgery in the supraorbital region.

Reappraisal of Supraorbital Sensory Nerve Conduction Recordings: Orthodromic and Antidromic Techniques

OBJECTIVE: To establish a supraorbital nerve sensory conduction recording method and assess its usefulness. METHODS: Thirty-one healthy subjects without a history of trauma or neurological disease were recruited. For the orthodromic procedure, the recording electrode was attached immediately superior to the supraorbital notch. The stimulation electrode was placed on points along the hairline which evoked the largest sensory nerve action potentials (SNAPs). The antidromic sensory response was recorded after switching the recording and stimulating electrodes. The measured parameters were onset latency, peak latency, and baseline to peak amplitude of the SNAPs. The electrophysiological parameters of the bilateral supraorbital nerves were compared. We also recruited two patients who had sensory deficits on one side of their foreheads because of laceration injuries. RESULTS: The parameters of orthodromically recorded SNAPs were as follows: onset latency 1.21±0.22 ms (range, 0.9-1.6 ms), peak latency 1.54±0.23 ms (range, 1.2-2.2 ms), and baseline to peak amplitude 4.16±1.92 µV (range, 1.4-10 µV). Those of antidromically recorded SNAPs were onset latency 1.31±0.27 ms (range, 0.8-1.7 ms), peak latency 1.62±0.29 ms (range, 1.3-2.2 ms), and baseline to peak amplitude 4.00±1.89 µV (range, 1.5-9.0 µV). There was no statistical difference in onset latency, peak latency, or baseline to peak amplitude between the responses obtained using the orthodromic and antidromic methods, and the parameters also revealed no statistical difference between the supraorbital nerves on both sides. CONCLUSION: We have successfully recorded supraorbital SNAPs. This conduction technique could be quite useful in evaluating patients with supraorbital nerve lesions.

Supraorbital Foramen - Morphometric Study and Clinical Implications in Adult Indian Skulls.

Introduction: Supraorbital foramen is an important site for various surgical and anesthetic procedures. Accurate localization of the foramen holds the key to success, although racial variations exist in various population groups. Th e study included the morphometry of supraorbital foramen and its location with respect to nearby anatomical landmarks. Methods: A total of 100 dry skulls (60 male and 40 female) were collected and observed for the study. Various parameters in the sagittal and transverse planes were noted from supraorbital foramen on both sides, together with its vertical and horizontal dimensions. In addition, the location of supraorbital foramen with respect to midline and frontozygomatic suture were noted. Results: Th e study of 100 adult skulls revealed that the SON (71% on right and 70% on left) was found more frequently than the SOF (29% on right and 30% on left).Th e distance between centre of SOF/SON and midline was found to be statistically signifi cant on right and left sides. Conclusions: Th is study makes possible the identifi cation of exact position of supraorbital foramen and also discuss its racial variation.

A Case Report of Surgical Treatment for Relief of Intractable Pain Developed after Browlift Surgery

PURPOSE: Nerve injury is one of the complication which can develop after brow lift. Peripheral nerve ending which is stretched from supraorbital nerve and supratrochlear nerve can be injured and symptoms such as pain, dysesthesia may appear. Usually, developed pain disappeared spontaneously and does not go on chronic way. We experienced a case that a patient complained chronic pain after brow lift which was not controlled by conservative management such as medications, local nerve block and report a successful surgical treatment of chronic pain after brow lift. METHODS: A 24-year-old male who received brow lift with hairline incision at local hospital was admitted for chronic pain at the right forehead. The pain was continued for 3 months even though fixed thread was removed. Local nerve block at trigger point with mixed 1mL 2% lidocaine and 1mL Triamcinolone acetonide was done and oral medications, Gabapentine and carbamazepine, were also applied but there was no difference in the degree of pain. Therefore the operation was performed so that careful dissection was carried out at right supraorbital neurovascular bundle and adhered supraorbital nerve was released from surrounding tissues and covered with silastic sheet to prevent adhesion. RESULTS: The pain was gradually relieved for a week. The patient was discharged without complications. No evidence of recurrence has been observed for 2 years. CONCLUSION: The pain developed after brow lift was engaged with nerve injury and sometimes remains chronically. Many kinds of conservative management to treat this complication such as medications, local nerve block have been reported and usually been used. But there are some chronic cases that conservative treatment do not work. In sum, we report 1 case of successful surgical treatment for relief of intractable pain developed after brow lift surgery.

A study of supraorbital notches and foramina in Gujarati human skulls.

The anatomy of the supraorbital notches and foramina has been studied in 249 human skulls. Of 233 skulls, 35.62% had bilateral supraorbital notches, 21.45% had bilateral supraorbital foramina and 16.73% had a notch on one side and a foramen on other side. In present study, total 13 types of combinations were found. The average distance from the nasion to the supraorbital notch/ foramen was 24.30 mm( 16.74-31.86) on right side and 23.73 mm (15.78-31.86) on left side. The exit point can be significantly cephaled to the orbital rim. Knowledge of the anatomy of the region is important for those doing forehead and brow lift surgeries in order to avoid injuring the neuro-vascular bundle passing through these notches/foramina.

Anatomical Consideration of the Anterior and Lateral Cutaneous Nerves in the Scalp

To better understand the anatomic location of scalp nerves involved in various neurosurgical procedures, including awake surgery and neuropathic pain control, a total of 30 anterolateral scalp cutaneous nerves were examined in Korean adult cadavers. The dissection was performed from the distal to the proximal aspects of the nerve. Considering the external bony landmarks, each reference point was defined for all measurements. The supraorbital nerve arose from the supraorbital notch or supraorbital foramen 29 mm lateral to the midline (range, 25-33 mm) and 5 mm below the supraorbital upper margin (range, 4-6 mm). The supratrochlear nerve exited from the orbital rim 16 mm lateral to the midline (range, 12-21 mm) and 7 mm below the supraorbital upper margin (range, 6-9 mm). The zygomaticotemporal nerve pierced the deep temporalis fascia 10 mm posterior to the frontozygomatic suture (range, 7-13 mm) and 22 mm above the upper margin of the zygomatic arch (range, 15-27 mm). In addition, three types of zygomaticotemporal nerve branches were found. Considering the superficial temporal artery, the auriculotemporal nerve was mostly located superficial or posterior to the artery (80%). There were no significant differences between the right and left sides or based on gender (P>0.05). These data can be applied to many neurosurgical diagnostic or therapeutic procedures related to anterolateral scalp cutaneous nerve.

Pulsed Radiofrequency Treatment of the Supraorbital and Supratrochlear Nerve in a Case of Trigeminal Neuralgia: A case report

Pharmacological management is the first choice for treatment of the trigeminal neuralgia patients; however, if this mode of treatment fails a minimally invasive procedure should be performed. One of the most commonly used procedures is conventional radiofrequency lesioning of the Gasserian ganglion. Despite its popularity and success rate, this technique has disadvantages such as diminished corneal reflex, masseter weakness, numbness and anesthesia dolorosa. As a result, many studies have been conducted in an attempt to find a better method of treating trigeminal neuralgia. We report here a case of a trigeminal neuralgia patient that was treated with pulsed radiofrequency lesioning of the supraorbital and supratrochlear nerve due to pain in the frontal head that was refractory to the pharmacological treatments. Following the procedure, the Visual Analogue Scale score for pain decreased to 1-2/10 and the pain relief persisted for 7 months. These results indicate that pulsed radiofrequency treatment of the peripheral nerve may be useful for trigeminal neuralgia patients that do not respond to pharmacological treatments.