CASE REPORT
Nagoya J. Med. Sci. 85. 179–184, 2023
doi:10.18999/nagjms.85.1.179

Transorbital penetrating head injury by a wooden chopstickin the cavernous sinus: a case report and literature review
Daisuke Yamazaki1, Naoki Ogihara1, Takehiro Yako1, Yu Fujii1,
Yoshiki Hanaoka1, Toru Kurokawa2 and Tetsuyoshi Horiuchi1
21
Department of Neurosurgery, Shinshu University School of Medicine, Matsumoto, Japan
Department of Ophthalmology, Shinshu University School of Medicine, Matsumoto, JapanABSTRACT
Penetrating head injury is a relatively rare condition associated with high morbidity and mortality.
Although the immediate treatment of penetrating head injury is needed, surgical strategies are varied basedon the trajectory of the penetrating objects in the cranium. We present a case of 24-year-old man who
sustained a transorbital penetrating injury caused by a wooden chopstick. Neuroimages revealed a linear
lesion extending from the left intraorbital segment to the cavernous sinus passing through the superior
orbital fissure. The foreign body was successfully removed via the transcranial approach without complications. A careful management based on the perioperative images and correct diagnosis is necessary to avoid
unfavorable complications. Four cases of transorbital penetrating injuries have been previously reported, inwhich the foreign body penetrated through the superior orbital fissure and lodged in the cavernous sinus.
The frontotemporal craniotomy with extradural approach can be a useful option to remove foreign bodies
around the cavernous sinus regions.
Keywords: superior orbital fissure, cavernous sinus, wooden foreign body
Abbreviations:
PHI: penetrating head injury
SOF: superior orbital fissureThis is an Open Access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
License. To view the details of this license, please visit (http://creativecommons.org/licenses/by-nc-nd/4.0/).

INTRODUCTION
Penetrating head injury (PHI) is a relatively rare condition accounting for 0.4% of all headtrauma.1 Particularly, transorbital penetrating injuries represent 24% of PHIs in adults and 45%of PHIs in children.2 Although early surgical treatment for the transorbital penetrating injury is
critical due to the high rates of cerebral complications, surgical approaches are varied based on
the location of the fragment in the cranium, to expose and remove foreign bodies safely.3 Fourcases of transorbital penetrating injuries have been previously reported where the foreign body had
Received: January 5, 2022; accepted: March 15, 2022
Corresponding Author: Daisuke Yamazaki, MD
Department of Neurosurgery, Shinshu University School of Medicine,
3-1-1 Asahi, Matsumoto 390-8621, Japan
Tel: +81-263-37-2690, Fax: +81-263-37-0480, E-mail: dyamazaki1218@shinshu-u.ac.jp179

Daisuke Yamazaki et alpenetrated through superior orbital fissure (SOF) and lodged in cavernous sinus.1,4-6 Herein, we
present a case of transorbital penetrating injury that was successfully treated via frontotemporalcraniotomy along with a literature review.

CASE REPORT
Case description
A 24-year-old man was struck at his left eye with a wooden chopstick and was transferredto our emergency department three hours after the assault with complain of headache, vomiting
and bleeding from the wound. A linear wound about 5 mm in length was observed at the medialaspect of the left lower eyelid (Fig. 1A) during physical examination. The shaft of the chopstick
had broken and was not visible outside. His eyelid was swollen and he could not open his left
eye. Ocular examination showed the pupil of his left eye was fixed and dilated 4 mm without
reaction to light. Although the injured eye had limited movements in all directions, visual acuity
was preserved at least counting fingers and the anterior ocular segment, optic media, and eyegroundwere not damaged by intraocular examination. No other serious neurological deficit was noted.
Computed tomography revealed a linear hypodense lesion extending from the left intraorbital
segment to the left cavernous sinus passing through the SOF, which suggested the foreign body.
Although a medial orbital wall fracture and intraorbital hemorrhage were evident, there was no
subarachnoid hemorrhage or brain contusion (Fig. 1B). Magnetic resonance imaging showed
the foreign body as a linear signal void subject in T1 and T2 weighted images. The tip of theforeign body ended immediately near the internal carotid artery, but there was no evidence ofthe carotid artery injury (Fig. 1C, D).

Fig. 1 Clinical photograph and preoperative neuroimages
Fig. 1A: Photograph of the patient shows a minor wound (arrow) at the middle aspect of the left lower eyelid
which indicating the entrance to the orbit.
Fig. 1B: Computed tomography show a linear hypodense lesion extending from the left intraorbital segment to
the left cavernous sinus passing through the SOF (superior orbital fissure).
Fig. 1C–1D: T1 and T2 weighted magnetic resonance imaging reveal a wooden foreign body as a linear low
intensity subject (arrowheads).
Nagoya J. Med. Sci. 85. 179–184, 2023

180

doi:10.18999/nagjms.85.1.179

Transorbital penetrating injury

Operation
The removal surgery for a wooden foreign body penetrating the cavernous sinus was performed. Under the general anesthesia, a left frontotemporal craniotomy was performed. With theretraction of the frontal lobe, the sphenoid ridge was drilled off epidurally under microscope(Fig. 2A). After the meningo-orbital band was detected, further bone removal of lateral part of
the SOF was carried out. Adhesion between the dura and the periorbita was dissected, then atip of the chopstick was discovered (Fig. 2B). The chopstick was pulled and removed along
its trajectory through the cavernous sinus with gentle dissection of the connective tissue aroundit (Fig. 2C, D). Hemostatic agents were carefully used to achieve hemostasis in the cavernoussinus. After hemostasis was confirmed in the epidural space, the wound was closed in the usual
manner without drainage.

Fig. 2 Intraoperative photographs
Fig. 2A: The sphenoid ridge was drilled off epidurally with the retraction of the frontal lobe.
Fig. 2B: A tip of the chopstick was identified passing through the SOF (superior orbital fissure).
Fig. 2C: The chopstick was pulled and removed along its trajectory through the cavernous sinus.
Fig. 2D: A fragment of the wooden chopstick and a fully intact chopstick are shown.

Postoperative course
The patient continued antibiotics. Although the left trochlear nerve palsy had persisted, thedilation of his pupil and visual acuity improved to 1.0. He was discharged on postoperative day
15. Postoperative neuroimages showed no significant abnormal findings (Fig. 3A, B). He wasfollowed up for six months and there were no signs suggesting an infection.

Nagoya J. Med. Sci. 85. 179–184, 2023

181

doi:10.18999/nagjms.85.1.179

Daisuke Yamazaki et al

Fig. 3 Postoperative neuroimages
Fig. 3A–3B: Postoperative computed tomography and T2 weighted magnetic resonance imaging show no evidenceof the residual foreign body.

DISCUSSION
We report a rare case of transorbital penetrating injury by a wooden chopstick. While determining the presence of fragments in the wound can be challenging, foreign bodies remaining
in the cranium can cause serious complications including intracranial hematoma, subarachnoid
hemorrhage, brain stem injury and vascular damage.3 Moreover, in case of wooden foreign bodies,
the porous organic materials provide a good culture for bacteria and meningitis or brain abscesscan easily occur.2,7 Herein, immediate treatment of the patient with PHI is needed due to highmorbidity and mortality caused by these complications.8
The potential risk of brain injury depends on the trajectory of the penetrating objects. In
transorbital penetrating injury, there are three major trajectories through which foreign bodies
penetrate intracranial region: the superior orbital fissure, optic canal and the orbital roof. As
the orbit is uniquely structured like a horizontal pyramid with an apex, penetrating objects areusually directed toward the apex passing through the SOF or optic canal. The orbital roof isalso a common trajectory due to the fragility of the superior orbital plate of the frontal bone.
In case of penetration through the optic canal or the orbital roof, foreign body can cause optic
nerve injury or frontal lobe contusion. However, in case of the SOF, wooden objects are usually
directed into the brain stem through the cavernous sinus, which may result in the cavernous
sinus and internal carotid artery injuries or brain stem and cerebellar injuries.1,3 In the present
case, fortunately, there was no evidence of intraaxial damage. Although the oculomotor nerve
palsy was evident preoperatively, the symptoms of his pupil and eye movement were improvedin the postoperative course as the nerve damage was reversible. His visual acuity was also fully
Nagoya J. Med. Sci. 85. 179–184, 2023

182

doi:10.18999/nagjms.85.1.179

Transorbital penetrating injury

Table 1 Summary of published transorbital penetrating injury by wooden foreign body lodged in cavernous sinus

Authors(year)

AgeSexFB type

Wound

Trajectory

Surgicalapproach

OutcomeBorkaret al1 (2014)

10F

WoodenstickMedial
canthus of
the right eye

SOF

Frontotemporalcraniotomy
with transorbital
extraction

Enucleation of
the right eye

SOF

Frontotemporalcraniotomy
with transorbital
extraction

No light
perception
ophthalmoplegia

Parajuli
et al4 (2015)

14F

BambooLeft lowereyelidAvraham
et al5 (2020)

71

M

Woodenstick

Left superior
eyelidSOF

Subtemporalcraniotomy

No light
perception
ophthalmoplegia

Hermann
et al6 (2021)

37

M

Woodenstick

NASOF

Frontotemporalcraniotomy

No light
perception
ophthalmoplegia

Presentcase

24

M

Woodenchopstick

Left lower
eyelidSOF

Frontotemporalcraniotomy

The left trochlear
nerve palsy

F: female
FB: foreign body
M: maleNA: not available
SOF: superior orbital fissure

recovered. The preoperative intraocular examination indicated that his transient visual obscuration
was caused by the multiple elements including the diplopia, the swelling eyelid and the dilated
pupil due to the traumatic event rather than optic neuropathy.
The strategies for removing a foreign body retained in the cranium depend on the locationof the fragment. In presented case, neuroimages showed the presence of foreign body extending
from the left intraorbital segment to the cavernous sinus ended just along the interdural space ofthe lateral cavernous sinus wall. In previous reports, transorbital penetrating injuries by foreign
body lodged in cavernous sinus were extremely rare (Table 1) and transcranial approach was
mainly documented.1,4-6 Although transorbital approach is a useful option to remove foreign
body as orbitotomy is less invasive and can be accomplished without intracranial manipulation,
craniotomy is preferred when intracranial injury is suspected.1,5 A frontotemporal craniotomy
can provide wide exposure of SOF and cavernous sinus as to allow sufficient microsurgicalmanipulation to repair dural defects or vessel injury. Moreover, we adopted an extradural approachwith a frontotemporal craniotomy as a reasonable alternative approach for removal of the foreign
body because this approach could provide wide exposure of the cavernous sinus regions without
direct intradural manipulation. Especially in case of a penetrating injury by wooden foreign bodywith high risk of infection, the procedure could completely achieve extradural manipulation andprevent brain infection.

Nagoya J. Med. Sci. 85. 179–184, 2023

183

doi:10.18999/nagjms.85.1.179

Daisuke Yamazaki et al

CONCLUSION
Transorbital penetrating injury caused by a wooden chopstick is rare condition and has apotential risk of severe complications. Although the surgical treatment of PHI is not standardized,
the frontotemporal craniotomy with extradural approach is a useful option for the removal offoreign bodies around the cavernous sinus regions.

CONFLICTS OF INTEREST
The authors declare that they have no competing interests.

FUNDING
This research received no specific grant from any funding agency in the public, commercial,or not-for-profit sectors.

REFERENCES
1Borkar SA, Garg K, Garg M, Sharma BS. Transorbital penetrating cerebral injury caused by awooden stick: surgical nuances for removal of a foreign body lodged in cavernous sinus. Childs Nerv Syst.
2014;30(8):1441–1444. doi:10.1007/s00381-014-2364-0.
2 Mzimbiri JM, Li J, Bajawi MA, Lan S, Chen F, Liu J. Orbitocranial low-velocity penetrating injury: apersonal experience, case series, review of the literature, and proposed management plan. World Neurosurg.
2016;87:26–34. doi:10.1016/j.wneu.2015.12.063.
3 Sun G, Yagmurlu K, Belykh E, Lei T, Preul MC. Management strategy of a transorbital penetrating pontine
injury by a wooden chopstick. World Neurosurg. 2016;95:622.e7-622.e15. doi:10.1016/j.wneu.2016.07.104.
4 Parajuli A, Bastola J, Shrestha GB, Shrestha JB. A case of transorbital intracranial injury presenting withsubtle neurological deficit. Nepal J Ophthalmol. 2015;7(14):186–190. doi:10.3126/nepjoph.v7i2.14977.
5 Avraham E, Smolikov A, Smolyakov R, et al. Minimally invasive subtemporal intradural approach forpenetrating orbitocranial injury by wooden foreign body into the lateral wall of the cavernous sinus. FrontSurg. 2020;7:533–567. doi:10.3389/fsurg.2020.533567.
6 Hermann AL, Lecler A. Post-traumatic retained foreign body in the cavernous sinus. Interdiscip Neurosurg.
2021;23:100959. doi:10.1016/j.inat.2020.100959.
7 Matsuyama T, Okuchi K, Nogami K, Hata M, Murao Y. Transorbital penetrating injury by a chopstick – casereport. Neurol Med Chir (Tokyo). 2001;41(7):345–348. doi:10.2176/nmc.41.345.
8 Samuthrat T, Ye K, Tong Y. Transoral intracranial injury via middle skull base by a blunt chopstick in achild. World Neurosurg. 2017;103:952.e11–952.e17. doi:10.1016/j.wneu.2017.04.084.
References EndNagoya J. Med. Sci. 85. 179–184, 2023

184

doi:10.18999/nagjms.85.1.179