Scleral and choroidal calcifications in a patient with pseudohypoparathyroidism

Diagnosis and Management Strategies in Sclerochoroidal Calcification: A Systematic Review

Sclerochoroidal calcification (SCC) is a rare disease which is characterized by calcium deposition in the sclera. The choroid is secondarily involved. Typical localization is in the midperipheral region, outside the vascular arcades. SCC is mostly located in the superotemporal quadrant. Often times, the patients are referred with the diagnosis of an amelanotic tumor. SCC may be dystrophic or metastatic. Metastatic SCC lesions are associated with conditions altering calcium and phosphate metabolism including primary and secondary hyperparathyroidism, vitamin D intoxication, renal failure, hyperphosphatemia, and destructive bony lesions. SCC lesions have a characteristic appearance and appear as distinct, ill-defined, yellow-white, elevated scleral/choroidal masses funduscopically. The purpose of this literature review is to review the current knowledge on SCC, highlight the imaging features, and discuss the differential diagnosis as well as management options.

A Case of Extensive Bilateral Idiopathic Sclerochoroidal Calcification and Review of Literature

A 62-year-old Caucasian male was referred to retina for choroiditis and uveitis. Multiple areas of yellow irregularities were noted on fundus exam throughout the periphery of both eyes, corresponding to lesions at the sclerochoroidal junction on OCT. A diagnosis of sclerochoroidal calcifications (SCC) was confirmed by B-ultrasonography, fundus photography, OCT imaging, and fluorescein and indocyanine green angiography. Systemic metabolic studies were performed, which showed reduced renal function with increased serum calcium; however, SCC lesions in this case were most likely idiopathic. In this work, we report the clinical findings, appearance on multimodal imaging, and systemic associations of sclerochoroidal calcification. Sclerochoroidal calcifications are an unusual clinical finding that tends to be idiopathic, but a focused workup and specialist referral may be warranted to exclude systemic conditions associated with abnormal calcium-phosphate metabolism or hypokalemic metabolic alkalosis syndromes.

Conjunctival calcinosis circumscripta in a dog: Treatment combining surgical resection and amniotic membrane grafting

This report describes the clinical features, histopathology, and surgical treatment of a case of conjunctival calcification in a 5-month-old female English Setter, referred with a history of recurrent conjunctivitis in the right eye (OD). The ophthalmic findings were limited to multifocal white plaques embedded in a markedly inflamed conjunctiva of the eyelids and the anterior nictitating membrane OD. Calcification was suspected. The blood cell count, blood chemical profile, and urinalysis were within normal limits, and long-bone radiographs appeared normal. After removal of the affected area by means of a large conjunctivectomy, cryopreserved canine amniotic membrane (AM) was transplanted to fill in the defect. Multifocal ectopic calcium deposits in the conjunctival lamina propria were confirmed histopathologically. The postoperative healing was uneventful, and no recurrence was observed during a follow-up period of five years. Conjunctival mineralization is uncommon in canine ophthalmology, and the cause remained undetermined in the present case, for which AM transplantation was able to promote conjunctival healing after a large surgical excision.

Idiopathic Sclerochoroidal Calcification: New Observations

Two cases of idiopathic sclerochoroidal calcification are reported with follow-up of two and ten years. In addition we have reviewed 102 cases of choroidal osteoma, including six misleading case reports which actually described idiopathic sclerochoroidal calcification and not choroidal osteoma. Clinical manifestation and the angiographic features of idiopathic sclerochoroidal calcification are outlined. The differential diagnosis of intraocular deposition of calcium salts is discussed in detail.

A single gene connects stiffness in glaucoma and the vascular system

Arterial calcification results in arterial stiffness and higher systolic blood pressure. Arterial calcification is prevented by the high expression of the Matrix-Gla gene (MGP) in the vascular smooth muscle cells (VSMC) of the arteries' tunica media. Originally, MGP, a gene highly expressed in cartilage and VSMC, was found to be one of the top expressed genes in the trabecular meshwork. The creation of an Mgp-lacZ Knock-In mouse and the use of mouse genetics revealed that in the eye, Mgp's abundant expression is localized and restricted to glaucoma-associated tissues from the anterior and posterior segments. In particular, it is specifically expressed in the regions of the trabecular meshwork and of the peripapillary sclera that surrounds the optic nerve. Because stiffness in these tissues would significantly alter outflow facility and biomechanical scleral stress in the optic nerve head (ONH), we propose MGP as a strong candidate for the regulation of stiffness in glaucoma. MGP further illustrates the presence of a common function affecting key glaucomatous parameters in the front and back of the eye, and thus offers the possibility for a sole therapeutic target for the disease.

Pseudohypoparathyroidism - epidemiology, mortality and risk of complications

OBJECTIVE

Pseudohypoparathyroidism (PHP) is caused by a mutation within the GNAS gene or upstream of the GNAS complex locus. It is characterized by target organ resistance to PTH, resulting in hypocalcaemia and hyperphosphataemia. Studies in patients with PHP are limited. We sought to identify all patients in Denmark with PHP and access their mortality data and risk of complications.

DESIGN

Patients were identified through the Danish National Patient Registry and a prescription database, with subsequent validation by investigation of patient charts.

METHODS

For each case, three age- (±2 years) and gender-matched controls were randomly selected from the general background population. We identified a total of 60 cases, equal to a prevalence of 1·1/100 000 inhabitants. The average age at diagnosis was 13 years (range 1-62 years), and 42 were women. Only 14 patients had an identified mutation in the GNAS1 gene.

RESULTS

Compared with controls, patients with PHP had an increased risk of neuropsychiatric disorders (P < 0·01), infections (P < 0·01), seizures (P < 0·01) and cataract (P < 0·01), whereas their risk of renal, cardiovascular, malignant disorders and fractures was compatible with the general background population. The same tendencies were found in a subgroup analysis in cases with genetically verified PHP.

CONCLUSION

Patients with PHP have an increased risk of neuropsychiatric disorders, infections, cataract and seizures, whereas mortality among PHP patients is compatible with that in the background population.

A Novel Mgp-Cre Knock-In Mouse Reveals an Anticalcification/Antistiffness Candidate Gene in the Trabecular Meshwork and Peripapillary Scleral Region

PURPOSE

Soft tissue calcification is a pathological condition. Matrix Gla (MGP) is a potent mineralization inhibitor secreted by cartilage chondrocytes and arteries' vascular smooth muscle cells. Mgp knock-out mice die at 6 weeks due to massive arterial calcification. Arterial calcification results in arterial stiffness and higher systolic blood pressure. Intriguingly, MGP was highly abundant in trabecular meshwork (TM). Because tissue stiffness is relevant to glaucoma, we investigated which additional eye tissues use Mgp's function using knock-in mice.

METHODS

An Mgp-Cre-recombinase coding sequence (Cre) knock-in mouse, containing Mgp DNA plus an internal ribosomal entry site (IRES)-Cre-cassette was generated by homologous recombination. Founders were crossed with Cre-mediated reporter mouse R26R-lacZ. Their offspring expresses lacZ where Mgp is transcribed. Eyes from MgpCre/+;R26RlacZ/+ (Mgp-lacZ knock-in) and controls, 1 to 8 months were assayed for β-gal enzyme histochemistry.

RESULTS

As expected, Mgp-lacZ knock-in's TM was intensely blue. In addition, this mouse revealed high specific expression in the sclera, particularly in the peripapillary scleral region (ppSC). Ciliary muscle and sclera above the TM were also positive. Scleral staining was located immediately underneath the choroid (chondrocyte layer), began midsclera and was remarkably high in the ppSC. Cornea, iris, lens, ciliary body, and retina were negative. All mice exhibited similar staining patterns. All controls were negative.

CONCLUSIONS

Matrix Gla's restricted expression to glaucoma-associated tissues from anterior and posterior segments suggests its involvement in the development of the disease. Matrix Gla's anticalcification/antistiffness properties in the vascular tissue, together with its high TM and ppCS expression, place this gene as a strong candidate for TM's softness and sclera's stiffness regulation in glaucoma.

Idiopathic sclerochoroidal calcification

PURPOSE

Sclerochoroidal calcification is a rare ocular condition characterized by multifocal, yellow-white elevated fundus lesions typically located in the superotemporal quadrant along the superior arcades. The pathology of calcification can be classified as dystrophic, metastatic, or idiopathic. Vision-threatening complications may arise, such as choroidal neovascular membrane and serous retinal detachment. The pathogenesis of sclerochoroidal calcification remains unclear.

CASE REPORT

A 72-year-old Caucasian male patient presented to the clinic for routine examination. Fundus evaluation revealed bilateral, multifocal, pale yellow elevated lesions in the superotemporal fundus. Ultrasonography showed a focal area of hyper-reflectivity located in the posterior retina of both eyes, and optical coherence tomography showed an intact retina overlying the elevated lesions in the choroid. Systemic evaluation for dystrophic and metastatic calcification was negative, and the patient was diagnosed with idiopathic sclerochoroidal calcification.

CONCLUSIONS

It is important to distinguish sclerochoroidal calcification from other conditions to prevent unnecessary intervention. Calcification of body tissues warrants a systemic evaluation, including screening for calcium and phosphorous levels, to rule out underlying systemic disease. If a biochemical abnormality is discovered, it can be appropriately treated with supplements. If calcification is deemed idiopathic, then annual dilated examinations are recommended to monitor the fundus lesions. Visual prognosis for sclerochoroidal classification is good, as the lesions are typically located away from the macula and foveal encroachment is rare.

Intraarticular heterotopic ossification as the initial manifestation in a child with pseudohypoparathyroidism 1a

The authors describe a 6 year old girl who initially presented with limping due to intraarticular ossification of left knee joint but later developed carpopedal spasms. She had Albright's hereditary osteodystrophy phenotype with hypocalcemia and hyperphosphatemia with elevated parathyroid hormone. She was diagnosed to have pseudohypoparathyroidism 1a (PHP1a) with heterotopic intraarticular ossification. This case emphasizes the need for evaluation of PHP in patients with intraarticular ossification to facilitate early diagnosis of PHP.

Idiopathic sclerochoroidal calcification

BACKGROUND

Idiopathic sclerochoroidal calcification (ISC) is an uncommon condition of calcium deposition at the level of the sclera and choroid of the posterior pole. With normal acuity and visual field, it typically manifests in asymptomatic older males. It can be diagnosed on clinical grounds, appearing as multiple geographic, yellowish, placoid-like lesions in the sclera and choroid, commonly found in the superotemporal arcade of the midperipheral fundus in both eyes. Ocular ultrasound and fluorescein angiography have classic results.

CASE REPORT

An 85-year-old white man came to us for routine examination. Best-corrected visual acuity was 20/40 O.D. and O.S. Dilated fundus examination revealed several midperipheral yellowish-white deposits with retinal pigment epithelium hyperpigmentation temporally in each eye. Ocular ultrasound revealed high reflectivity consistent with calcium. The lesions demonstrated mild hyperfluorescence in the late phase of fluorescein angiography. Laboratory testing was void of abnormal calcium or phosphorous metabolism, and a diagnosis of ISC was made.

CONCLUSION

Idiopathic sclerochoroidal calcification is a benign lesion of calcium deposition in the posterior pole, often discovered on routine examination. Although it is idiopathic, systemic evaluation is warranted to rule out dystrophic or metastatic calcification by various pathological conditions associated with abnormal calcium-phosphorus metabolism--most notably, hyperparathyroidism. Differential diagnoses include choroidal osteoma, melanoma, and metastatic carcinoma.

CME review: sclerochoroidal calcification: the 2001 Harold Gifford Lecture

Sclerochoroidal calcification is a recently recognized ocular condition that is characterized by typical geographic yellow-white fundus lesions that usually occur bilaterally in adults. It can clinically simulate a number of intraocular tumors like choroidal metastasis, choroidal melanoma, and choroidal osteoma. Clinical evaluation with ultrasonography, computed tomography, and some histopathologic studies have supported the fact the condition represents calcium deposition in the sclera and choroid. Early reports suggested that sclerochoroidal calcification was usually associated with hypercalcemic conditions such as hyperparathyroidism and pseudohypoparathyroidism. Subsequently, many patients with sclerochoroidal calcification have had no apparent systemic associations and have been classified as idiopathic. However, very recent studies have suggested that this ocular condition can also be associated with Gitelman syndrome or Bartter syndrome. These are autosomal recessive conditions of hypokalemic alkalosis associated with hypomagnesemia and deposition of calcium salts in various tissues. Ophthalmologists should be familiar with fundus features and systemic associations of sclerochoroidal calcification.

Calcification at the posterior pole in scleritis. A case report

We report a case with unilateral recurrent anterior scleritis which developed sclerochoroidal calcification at the posterior pole without any overt sign of posterior scleritis during the follow-up period of nine years. We believe that subtle posterior scleral inflammation might lead to sclerochoroidal calcification which might be dystrophic in nature.

Albright's hereditary osteodystrophy

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Idiopathic sclerochoroidal calcification

Idiopathic sclerochoroidal calcification is a disorder that is often overlooked, occurring at the level of the posterior sclera and choroid in older patients. Clinically, it may be confused with choroidal osteoma, choroidal metastasis, amelanotic choroidal nevus, or choroiditis. The authors present seven cases of this unusual entity. The patients ranged in age from 58 to 80 years. In all cases, the yellow lesions were clinically estimated to be at the level of the choroid and sclera, and they were usually located superior to the superotemporal retinal vascular arcade. Systemic investigation of calcium and phosphate metabolism was normal in all patients. The classic clinical manifestations and differentiation of this unusual entity from other similar fundus lesions is discussed.

Scleral calcification and photoreceptor cell death during aging and exposure to chronic stress

Male and female Fischer 344 rats of three different ages (12, 18, and 25 months) have been examined for the presence of photoreceptor (PR) cell loss and for occurrence of scleral cartilage and bone formation. In addition, male and female rats, aged 11 months at the beginning of the experiments, were exposed to chronic stress for either 0.5, 2, 4, or 6 months. Photoreceptor cell death gradually increases during the aging process and is exacerbated by exposure to chronic stress. It is more severe in the peripheral than the central retina and exposure to stress increases this pattern of cell loss. The superior retina is more severely affected than the inferior hemisphere in aging and during stress. The incidence of scleral cartilage or bone formation increases with age in male and female rats, but with stress exposure an increase is seen in males only. Bone formations occur more frequently in male than in female animals and are almost always (97%) located in the superior hemisphere of the eye. Although there appears to be a direct relationship between photoreceptor cell death and the occurrence of scleral ossifications in group data, in individual eyes the bone formations are not always associated with severity of PR cell loss. The relationship of PR cell death and incidence of scleral ossification to gender and to exposure to stress supports a hypothesis for an endocrine basis of ocular aging.

Choroidal osteoma

This review details the characteristic clinical features, diagnostic approaches, management, and prognosis of the choroidal osteoma. A comprehensive differential diagnosis is organized to help the ophthalmologist differentiate this tumor from conditions which can sometimes be clinically similar, such as amelanotic choroidal melanoma and nevus, metastatic choroidal carcinoma, choroidal hemangioma, metastatic and dystrophic intraocular calcification, and others. The pathology of the choroidal osteoma is illustrated and several theories of the pathogenesis of this tumor including the possibilities of a choristomatous, inflammatory, and hereditary etiology are discussed. The recently recommended therapeutic technique of photocoagulation of subretinal neovascularization associated with choroidal osteoma are discussed.