Scleral Exposure
bare sclera: Visible as a white area. This is the most characteristic finding of this disease.
Choroidal rupture: Involves full-thickness defects of the choroid, Bruch’s membrane, and retina.
Chorioretinitis Sclopetaria
Key points at a glance
Section titled “Key points at a glance”1. What is chorioretinitis sclopetaria?
Section titled “1. What is chorioretinitis sclopetaria?”Chorioretinitis sclopetaria is a closed-globe ocular injury caused by the impact of a high-velocity object passing near the eye. It is characterized by full-thickness rupture of the choroid, Bruch’s membrane, and retina, exposing the bare sclera.
This disease was first described by Herman Cohn in 1872. “Sclopetaria” is derived from the Latin word “sclopetum” (handgun). In 1901, Goldzieher described it as “chorioretinitis plastica sclopetaria.”
The injury occurs as a coup injury at the impact site. This differs from the usual choroidal rupture (contrecoup injury), where the shock wave damages the opposite side.
Q
How is it different from ordinary choroidal rupture?
A
Ordinary choroidal rupture occurs on the opposite side of the impact (contrecoup) and involves only the choroid. In contrast, chorioretinitis sclopetaria occurs at the impact site (coup) and involves full-thickness rupture of the choroid, Bruch’s membrane, and retina.
2. Main Symptoms and Clinical Findings
Section titled “2. Main Symptoms and Clinical Findings”
Andrew N Siedlecki; Edmund Tsui; Jie Deng; Donald M Miller. Long-Term Retention of an Intraorbital Metallic Foreign Body Adjacent to the Optic Nerve. Case Rep Ophthalmol Med. 2016 Oct 12; 2016:3918592 Figure 2. PMCID: PMC5080503. License: CC BY.
Color fundus photograph of the patient’s left eye demonstrating a comet-shaped temporal chorioretinal scar consistent with sclopetaria.
Subjective Symptoms
Section titled “Subjective Symptoms”The following symptoms appear after injury.
- Decreased vision: Severity varies depending on the location and extent of the rupture and hemorrhage.
- Floaters: Perception of floating objects due to vitreous hemorrhage.
- Visual field defect: May occur corresponding to the rupture site.
Clinical Findings
Section titled “Clinical Findings”Findings change between the acute and chronic phases.
Hemorrhagic Findings
Vitreous hemorrhage: Frequently observed in the acute phase. May obstruct fundus examination.
Subretinal hemorrhage and intraretinal hemorrhage: Occur extensively around the rupture site.
Other acute phase findings
Macular edema and optic disc edema: Appear in association with inflammatory response.
RAPD and extraocular muscle palsy: Findings suggestive of damage to the optic nerve or extraocular muscles.
Elevated intraocular pressure: May occur as secondary glaucoma due to trauma.
Chronic Phase Findings
Fibroglial scar: Forms several weeks after injury.
Claw-like border: Scar with irregular borders is characteristic.
3. Causes and Risk Factors
Section titled “3. Causes and Risk Factors”When a shock wave passes rapidly around the eyeball, its compressive force destroys the choroid and retina. Young males are the most common patient group.
Main causative objects are listed below.
| Classification | Examples |
|---|---|
| Projectiles | Air gun pellets, shot, bullets |
| Sports equipment | Paintballs |
| Others | Cork, tree branches, metal fragments |
Q
Can protective glasses prevent it?
A
Protective eyewear is an effective means of reducing the risk of eye injury from high-speed flying objects. However, it is difficult to completely prevent all injuries, such as those from direct impact. It is important to select protective glasses that meet appropriate standards for risky work or sports.
4. Diagnosis and Examination Methods
Section titled “4. Diagnosis and Examination Methods”Diagnosis is based on trauma history and fundus findings. In the acute phase, fundus observation may be limited by vitreous hemorrhage.
The main examination methods are shown below.
| Examination Method | Main Findings |
|---|---|
| Dilated fundus examination | Scleral exposure, hemorrhage |
| OCT | Choroidal and retinal pigment epithelium rupture |
| CT | Intraorbital foreign body |
The role of each examination is as follows.
- Dilated fundus examination: Confirm bare sclera, hemorrhage, and rupture site. Optos ultra-widefield imaging is useful for obtaining an overall view of the lesion.
- OCT (Optical Coherence Tomography): Evaluates the extent and depth of choroidal and retinal pigment epithelium rupture.
- CT: Confirms the presence and location of intraorbital foreign bodies. Also useful for differentiating from globe rupture.
- B-scan ultrasonography: Assesses the integrity of the ocular wall when the fundus is not visible due to vitreous hemorrhage.
- FA (Fluorescein Angiography): Confirms hypofluorescence at the rupture site. Also used to detect choroidal neovascularization.
Differential Diagnosis
Section titled “Differential Diagnosis”The following diseases require differentiation.
- Choroidal rupture: contrecoup type. Only the choroid is ruptured, not full-thickness.
- Traumatic macular hole: Full-thickness defect in the macula.
- Commotio retinae: White edematous changes without rupture.
- Retinal artery occlusion: White changes due to vasospasm or occlusion after trauma.
- Traumatic retinal detachment: Secondary detachment from the rupture site.
- Globe rupture: Full-thickness wound with low intraocular pressure and globe deformity.
5. Standard Treatment
Section titled “5. Standard Treatment”Observation
Section titled “Observation”In many cases, observation is the basic approach. Extensive fibroglial proliferation often leads to spontaneous scarring and closure of retinal breaks.
Surgical Indications
Section titled “Surgical Indications”Surgery is required if the following complications are present:
- Globe rupture: Emergency primary suturing is needed.
- Retinal detachment: Perform vitrectomy or scleral buckling.
- Intraocular foreign body: Perform foreign body removal.
The main surgical procedures are as follows.
- Pars plana vitrectomy (PPV): Removal of vitreous hemorrhage and repair of retinal detachment.
- Scleral buckling: Performed for rhegmatogenous retinal detachment.
- Foreign body removal: Performed when there is an intraocular or orbital foreign body.
- Enucleation: The last resort when eye preservation is impossible.
Management of Choroidal Neovascularization (CNV)
Section titled “Management of Choroidal Neovascularization (CNV)”Choroidal neovascularization may develop from the scar tissue after injury. In such cases, laser photocoagulation or intravitreal injection of anti-VEGF agents is performed.
Visual Prognosis
Section titled “Visual Prognosis”Visual prognosis is generally limited. The rate of achieving 20/20 vision is reported to be 16.4%. Ruptures involving the macula or optic nerve have a particularly poor prognosis.
Q
Is surgery always necessary?
A
In many cases, spontaneous healing due to fibroglial proliferation can be expected, so observation is the basic approach. However, surgery is necessary when complicated by retinal detachment, globe rupture, or intraocular foreign body. Regular fundus evaluation as described in Diagnosis and Examination Methods is important for early detection of complications.
Q
How much visual recovery can be expected?
A
The rate of achieving 20/20 vision is only 16.4%. Prognosis is particularly poor when the macula or optic nerve is involved in the rupture site, or when complicated by orbital fracture or optic neuropathy. It is difficult to predict the final outcome based solely on initial visual acuity.
6. Pathophysiology and Detailed Mechanism
Section titled “6. Pathophysiology and Detailed Mechanism”When a high-speed object passes near the eye, the resulting shock wave deforms the eyeball wall, detaching and rupturing the choroid and neurosensory retina from the sclera.
Differences in the elastic properties of each tissue layer determine the rupture pattern.
Bruch's membrane
Inelasticity: Vulnerable to compressive forces, rupturing even with relatively low energy.
Rupture initiation: Rupture of Bruch’s membrane causes acute subretinal hemorrhage from the choriocapillaris.
Retinal pigment epithelium
Inelasticity: Like Bruch’s membrane, it has poor elasticity and is prone to rupture.
Hyperplasia: In the chronic phase, retinal pigment epithelium hyperplasia occurs and contributes to scar formation.
Retina and Sclera
Elasticity: Relatively high elasticity, damaged only by high-energy impact.
Scleral preservation: The sclera has the highest elasticity and is usually preserved (bare sclera).
The pathological progression after injury is as follows.
- Acute phase: Bruch’s membrane/choroidal rupture → subretinal hemorrhage from the choriocapillaris.
- Subacute phase: Fibroblasts and glial cells are activated and begin migrating to the rupture site.
- Chronic phase: Fibrous tissue forms several weeks after injury, resulting in a claw-like scar.
In a histopathological study by Duboby in 1974, defects in Bruch’s membrane and choroid, loss of photoreceptors, and hyperplasia of the retinal pigment epithelium were confirmed.
7. Latest Research and Future Perspectives (Research-stage Reports)
Section titled “7. Latest Research and Future Perspectives (Research-stage Reports)”Relationship between fibrosis and retinal detachment
Section titled “Relationship between fibrosis and retinal detachment”Traditionally, fibroglial proliferation was thought to seal the rupture site and prevent retinal detachment. However, Papakostas (2014) reported that retinal detachment was actually confirmed in a case of sclopetaria with ocular injury, questioning the conventional concept that “fibrosis prevents detachment.”
Energy Dose and Visual Prognosis
Section titled “Energy Dose and Visual Prognosis”In the study by Ludwig et al., injuries from relatively low-energy objects such as air guns tended to have a poorer prognosis. Even when the impact energy was low, rupture of the temporal side or macula led to poor visual acuity, and the rate of achieving a final visual acuity of 20/20 was only 16.4% overall.
Injuries from high-energy objects (e.g., bullets) are diagnosed and treated early as globe rupture, whereas injuries from low-energy objects can damage the macula while preserving the eyeball structure, which is considered a factor contributing to poor prognosis.
References
Section titled “References”- Ludwig CA, Shields RA, Do DV, Moshfeghi DM, Mahajan VB. Traumatic chorioretinitis sclopetaria: Risk factors, management, and prognosis. Am J Ophthalmol Case Rep. 2019;14:39-46. PMID: 30834355.
- Dubovy SR, Guyton DL, Green WR. Clinicopathologic correlation of chorioretinitis sclopetaria. Retina. 1997;17(6):510-520. PMID: 9428014.
- Martin DF, Awh CC, McCuen BW 2nd, Jaffe GJ, Slott JH, Machemer R. Treatment and pathogenesis of traumatic chorioretinal rupture (sclopetaria). Am J Ophthalmol. 1994;117(2):190-200. PMID: 8116747.
- Papakostas TD, Yonekawa Y, Wu D, Miller JB, Veldman PB, Chee YE, Husain D, Eliott D. Retinal detachment associated with traumatic chorioretinal rupture. Ophthalmic Surg Lasers Imaging Retina. 2014;45(5):451-455. PMID: 25153657.
- Rayess N, Rahimy E, Ho AC. Spectral-domain optical coherence tomography features of bilateral chorioretinitis sclopetaria. Ophthalmic Surg Lasers Imaging Retina. 2015;46(2):253-255. PMID: 25707053.