Idiopathic
Most common category (approximately 79%): Calcification without any obvious systemic disease. An association with aging is suggested, but the detailed mechanism is unknown.
Often bilateral: Idiopathic cases can also present bilaterally.
Sclerochoroidal Calcification
Key Points at a Glance
Section titled “Key Points at a Glance”1. What is sclerochoroidal calcification?
Section titled “1. What is sclerochoroidal calcification?”Sclerochoroidal calcification (SCC) is a rare calcified lesion that occurs at the junction of the sclera and choroid. It usually follows a benign course and does not require specific treatment in most cases2).
Approximately 79% of SCC cases are idiopathic (cause unknown), and about 52% are bilateral2). The lesions occur at the sclerochoroidal junction in the peripheral to posterior fundus and appear as single or multiple yellowish-white elevated lesions.
This condition is often discovered incidentally during ophthalmic examinations, and the majority of cases remain asymptomatic. However, there have been reports of misdiagnosis as choroidal metastasis, melanoma, or even intraocular foreign body (IOFB)1), so accurate diagnosis is required.
Q
Is sclerochoroidal calcification related to cancer or tumors?
A
SCC is usually a benign calcified lesion and is not directly related to malignant tumors. However, differentiation from choroidal metastasis and melanoma is important, and confirmation with multimodal imaging such as EDI-OCT and CT is necessary.
2. Main symptoms and clinical findings
Section titled “2. Main symptoms and clinical findings”Subjective symptoms
Section titled “Subjective symptoms”Most SCC cases are asymptomatic and are discovered incidentally during routine fundus examinations.
- Decreased vision and metamorphopsia: Occur when the lesion involves the macula or when choroidal neovascularization (CNV) is present.
- Visual field abnormalities: Depending on the location and size of the lesion, peripheral visual field defects may occur.
Clinical Findings
Section titled “Clinical Findings”Fundus findings include yellowish-white to milky-white, flat to slightly elevated lesions at the sclerochoroidal junction. The lesions are usually well-defined and commonly occur in the superior to temporal region.
Various imaging tests show characteristic findings. The findings for each modality are shown below.
| Imaging Modality | Characteristic Findings |
|---|---|
| EDI-OCT | Rocky-rolling pattern |
| B-scan ultrasound | High-intensity echo and acoustic shadowing |
| FA/ICGA | Filling defect and hyperfluorescence |
| CT | High-density lesion of the ocular wall |
| Fundus photography | Yellowish-white elevated lesion |
EDI-OCT (enhanced depth imaging OCT) shows irregular undulations along the scleral surface (rocky-rolling pattern) as a characteristic finding 2). Calcified areas appear as hyperreflective regions with optical shadowing.
B-scan ultrasonography shows high-intensity echoes with posterior acoustic shadowing 2, 3). This finding is specific to calcified lesions and useful for diagnosis.
FA (fluorescein angiography) and ICGA (indocyanine green angiography) show filling defects in the lesion area and surrounding hyperfluorescence 2, 3).
CT (computed tomography) shows the lesion as a high-density area (consistent with calcification) in the ocular wall 1, 2). Cases have been reported where this high-density finding was mistaken for an intraocular foreign body (IOFB) 1).
Q
What is the rocky-rolling pattern on EDI-OCT?
A
The rocky-rolling pattern refers to irregular wavy undulations along the scleral surface, accompanied by hyperreflectivity due to calcification and posterior shadowing. It is a characteristic finding of SCC and an important basis for diagnosis using EDI-OCT.
3. Causes and Risk Factors
Section titled “3. Causes and Risk Factors”The causes of SCC are broadly classified into three categories 2).
Degenerative
Aging/degenerative changes: Secondary calcification due to degeneration of the sclera and choroid.
CPPD (calcium pyrophosphate deposition disease): Reported as a systemic disease accompanied by articular cartilage calcification (chondrocalcinosis).
Metastatic
Systemic disease origin: When there is an underlying systemic disease involving calcium and phosphorus metabolism abnormalities.
Main associated diseases: Hyperparathyroidism, Gitelman syndrome, hypomagnesemia, etc.
The reported frequencies of systemic diseases associated with SCC are shown below2).
| Systemic disease | Reported frequency |
|---|---|
| Hyperparathyroidism | Approximately 27% |
| Gitelman syndrome | Approximately 11% |
| CPPD (chondrocalcinosis) | Reported |
| Hypomagnesemia | Reported |
| Other Ca/P metabolism disorders | Reported |
Hyperparathyroidism is the most frequent associated systemic disease, found in approximately 27% of cases 2). Gitelman syndrome (a tubular disorder characterized by hypokalemia, hypomagnesemia, and hypouricemia) is associated in about 11% of cases 2).
An association with CPPD (calcium pyrophosphate deposition disease) has also been reported 2, 3), and in cases with articular cartilage calcification, the possibility of this disease should be considered. Hypomagnesemia is also cited as a cause of SCC 2).
4. Diagnosis and Examination Methods
Section titled “4. Diagnosis and Examination Methods”The diagnosis of SCC requires a combination of multimodal imaging.
Imaging Studies
Section titled “Imaging Studies”- EDI-OCT: Confirms the rocky-rolling pattern of the scleral surface and high reflectivity with acoustic shadowing at calcification sites. It is the most useful non-invasive test for definitive diagnosis of SCC 2).
- B-scan ultrasound: Confirms high-intensity echoes and posterior acoustic shadowing. Used to evaluate the size and depth of the lesion 2).
- CT: Depicted as a hyperdense lesion of the ocular wall. Useful for differentiation from IOFB and calcified tumors 1, 2).
- FA/ICGA: Used to evaluate CNV complications and vascular changes.
Systemic Evaluation
Section titled “Systemic Evaluation”The following blood and biochemical tests are recommended 2):
- Serum calcium, phosphorus, and alkaline phosphatase
- Parathyroid hormone (PTH)
- Serum magnesium and potassium
- Renal function (BUN, Cr)
Differential diagnosis
Section titled “Differential diagnosis”Choroidal metastasis
Common differential diagnosis: Check for the presence of a primary tumor. Calcification is scarce, and the rocky-rolling pattern is not seen on EDI-OCT.
CT/Ultrasound: High-density calcification shadows are not typical in metastatic lesions.
Choroidal melanoma
Differentiation from malignant tumors: Often has a high elevation and is pigmented. The internal echo pattern on ultrasound is different.
Fluorescein angiography: Melanoma may show a characteristic double circulation pattern.
Intraocular foreign body (IOFB)
High-density lesion on CT: History of trauma is important. SCC often has no trauma history and is bilateral.
Shape and distribution: SCC is characterized by an arcuate distribution at the sclerochoroidal junction. IOFB is localized 1).
Q
Can it be mistaken for an intraocular foreign body?
A
Since SCC appears as a high-density lesion on the ocular wall on CT, cases have been reported where SCC was mistaken for IBFB even in patients without a history of trauma. Detailed inquiry about trauma history and confirmation of EDI-OCT findings (rocky-rolling pattern) are important for differential diagnosis.
5. Standard Treatment
Section titled “5. Standard Treatment”Most SCCs follow a benign course, so observation is the basic policy2, 3).
Observation
Section titled “Observation”If asymptomatic and without visual impact, regular fundus examination and OCT follow-up are performed2, 3). The observation interval is set individually based on lesion size, location, and presence of systemic disease.
Treatment for CNV Complication
Section titled “Treatment for CNV Complication”In cases complicated by choroidal neovascularization (CNV), anti-VEGF therapy (intravitreal injection) may be effective2). The type and number of anti-VEGF injections are determined based on the activity and extent of the associated CNV.
Management of Systemic Disease
Section titled “Management of Systemic Disease”When systemic diseases such as hyperparathyroidism or Gitelman syndrome are identified, medical management of the underlying disease is important. Correction of calcium and magnesium metabolism may contribute to stabilization of ocular lesions.
6. Pathophysiology and Detailed Mechanism
Section titled “6. Pathophysiology and Detailed Mechanism”The main component of calcification in SCC is deposition of calcium pyrophosphate (CPP)2). Ectopic deposition of CPP at the sclera-choroid junction (outermost layer of the choroid) forms characteristic lesions.
Abnormal pyrophosphate metabolism and local tissue degeneration are thought to act as promoting factors for calcification. In Gitelman syndrome and hyperparathyroidism, systemic disruption of Ca/P metabolism induces ectopic calcification in the eye2).
Fundus autofluorescence (FAF) shows hyperautofluorescence at calcified sites2). This finding is presumed to reflect lipofuscin accumulation or autofluorescent properties of the calcified material itself. Secondary damage to the RPE (retinal pigment epithelium) may also affect the autofluorescence pattern.
Calcified lesions may enlarge and harden over time, which can lead to circulatory disturbances in the RPE and choriocapillaris, potentially triggering CNV.
7. Latest Research and Future Perspectives (Investigational Reports)
Section titled “7. Latest Research and Future Perspectives (Investigational Reports)”Improved Diagnostic Accuracy with EDI-OCT
Section titled “Improved Diagnostic Accuracy with EDI-OCT”With the widespread use of EDI-OCT, non-invasive and detailed morphological assessment of SCC has become possible. Diagnosis, which previously relied on B-scan ultrasound and CT, is shifting to more detailed layer-level evaluation 1, 2).
Mani and Johnson (2023) reported a case of SCC misdiagnosed as IOFB on CT 1). The case presented with a hyperdense lesion in the ocular wall without a history of trauma, and a rocky-rolling pattern was confirmed on EDI-OCT, leading to a definitive diagnosis of SCC. This report highlights the limitations of CT-only diagnosis and emphasizes the importance of combining it with EDI-OCT.
Thomson et al. (2021) reported a case of bilateral extensive idiopathic SCC with a review 2), showing that EDI-OCT plays a central role in precise lesion evaluation. They suggest that a multimodal approach combining B-scan, FA, ICGA, and CT enhances diagnostic certainty.
Documentation of Plaque-Type and Pseudotumor-Type Progression
Section titled “Documentation of Plaque-Type and Pseudotumor-Type Progression”Nabih et al. (2022) reported a case of SCC associated with CPPD (chondrocalcinosis) 3). In this case, plaque-like expanding calcification presented a fundus mass-like (pseudotumor) appearance, posing a clinical challenge in differentiating it from tumors. It was shown that SCC can progress in a plaque-like manner and exhibit a pseudotumor appearance, reaffirming the importance of imaging in differentiating it from neoplastic lesions.
Based on these findings, multicenter studies on the long-term natural course, classification, and progression predictors of SCC are considered future challenges.
Q
Does SCC worsen if left untreated?
A
Most cases follow a benign course with minimal impact on vision, and observation is the basic approach. However, some cases have been reported to show plaque-like enlargement or pseudotumor appearance. If CNV develops or visual function is affected, active treatment intervention is necessary, so regular ophthalmologic follow-up is important.
8. References
Section titled “8. References”- Mani X, Johnson R. Sclerochoroidal calcification masquerading as intraocular foreign body. Radiol Case Rep. 2023;18(5):2034-2038.
- Thomson AC, Poulsen CD, Wiencke アカントアメーバ角膜炎, et al. Extensive bilateral idiopathic sclerochoroidal calcification and review of the literature. Int Med Case Rep J. 2021;14:749-755.
- Nabih O, Hajji I, Lamari A, et al. Sclerochoroidal calcification associated with chondrocalcinosis. Ann Med Surg. 2022;74:103275.