PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Ciliary Body”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Postnatal development of the ciliary body and pars plana. A morphometric study in childhood.

The ciliary body of the human eye serves many vital functions and provides important access to the posterior segment of the globe in vitreoretinal surgery. Although embryogenesis and prenatal development of the ciliary body have been well documented, continuing development of the ciliary body during early childhood has not been studied extensively. We determined the lengths of the ciliary body and pars plana in 76 normal eyes of subjects who ranged in age from 1 week to 6 years. The ciliary body was found to be of substantial length soon after birth; it measured a mean of 3.06 mm nasally and 3.31 mm temporally. Three quarters of the final length of the ciliary body at adulthood was achieved by age 24 months. The growth of the ciliary body is discussed in relation to the growth of the eye.

Age Factors↗

Lacrimal gland choristoma of the ciliary body.

BACKGROUND: Lacrimal gland choristoma manifesting in the ciliary body is quite rare. We report a case of lacrimal gland choristoma manifesting in the ciliary body, coupled with orbital cellulites, in an infant. CASE: A 10-month-old female infant with swelling and tenderness of the right upper eyelid. OBSERVATIONS: The results of ophthalmic examinations of the patient were consistent with orbital cellulitis. During the funduscopic examination, a fleshy mass was incidentally detected at the superotemporal portion of the ciliary body in the right eye. A local resection of the lesion was carried out. The results of a pathologic examination showed lacrimal gland choristoma of the ciliary body that was accompanied by an epithelia-lined cyst. The patient has had no hypotonia or enlargement of the lesion for 1 year after surgery. CONCLUSION: Lacrimal gland choristoma should be included in the differential diagnosis of a ciliary body mass in pediatric patients.

Biopsy↗

Development of the ciliary body: a brief review.

The ciliary body is an important component in the tissue interactions that occur during the normal development of the eye. The ciliary epithelium is induced by the lens from the rim of the optic cup and probably reciprocates by determining the position of the germinative zone of the lens. The ciliary epithelium is also likely to induce the differentiation of the ciliary muscle and stroma from the surrounding neural crest-derived mesenchyme. Intraocular pressure plays a major role in co-ordinating the growth and morphogenesis of many ocular tissues, including the ciliary body. A central question addressed in this review is whether this pressure is generated by the early activity of the ciliary epithelium or by the growth and osmotic activity of the vitreous body.

Animals↗

Capsaicin releases calcitonin gene-related peptide from the human iris and ciliary body in vitro.

Slices of human iris or ciliary body, obtained post-mortem (8-12 h after death, n = 5), were superfused in vitro with capsaicin (10 microM) and the immunoreactivity for substance P (SP-LI) or calcitonin gene-related peptide (CGRP-LI) was measured in the effluent. In the iris and in the ciliary body CGRP-LI was 3.71 +/- 0.74 pmol/g and 3.01 +/- 0.55 pmol/g and SP-LI was 6.68 +/- 0.75 pmol/g and 6.55 +/- 0.84 pmol/g, respectively. A first exposure to capsaicin increased the CGRP-LI outflow from the ciliary body (427 +/- 46 fmol/g/30 min), whereas a second challenge with the drug 30 min later, failed to significantly enhance the CGRP-LI outflow (21.8 +/- 15.6 fmol/g/30 min). Likewise, the capsaicin-evoked increase in CGRP-LI outflow from the iris slices (472 +/- 62 fmol/g/30 min) was no longer observed at the second drug administration (38.4 +/- 12.8 fmol/g/30 min). Capsaicin failed to increase the SP-LI outflow from either the iris or the ciliary body. Reverse phase HPLC analysis of CGRP-LI indicated that authentic CGRP was contained in the tissue and in the superfusate collected during exposure to capsaicin. The present results show that in the human iris and ciliary body, capsaicin releases CGRP possibly contained in terminals of sensory nerves.

Calcitonin Gene-Related Peptide↗

Prostaglandin and thromboxane synthesis by microsomes of inflamed rabbit ciliary body--iris.

Microsomes of albino rabbit ciliary body--iris were prepared 6 hr, 24 hr, 3 days, 7 days, and 28 days after intravitreal injection of 10 micrograms of Shigella endotoxin. The microsomal preparations were incubated for 15 min with [1-14C]arachidonic acid. Prostaglandin and thromboxane products (cyclo-oxygenase products) were identified by thin-layer chromatography and quantified by scintillation counting. Synthesis of prostaglandin F2 alpha (PGF2, PGD2, 6-keto-PGF1 alpha (a stable metabolite of PGI2) and thromboxane B2 (TXB2) (a stable metabolite of TXA2) was increased 24 hr, 3 days, and 7 days after endotoxin injection. The greatest increase was in TXB2 synthesis. Cyclo-oxygenase product synthesis returned to normal levels by 28 days. Ciliary body--iris microsomes prepared 15 min after paracentesis synthesized increased amounts of all cyclo-oxygenase products assayed, most notably TXB2 and PGE2. Ciliary body--iris microsomes from albino rabbit treated with topical 1% nitrogen mustard or pigmented rabbits treated with subcutaneous alpha-melanocyte--stimulating hormone (20 micrograms/kg) synthesized normal amounts of cyclo-oxygenase products.

Animals↗

Human ciliary body epithelium in culture.

Human ciliary body epithelial cells have been maintained in vitro and have been partially characterized by the determination of growth rate, morphology, and ultrastructural parameters. The dissection technique employed allows the separation of pure ciliary body epithelium with a predominance of cells being from the nonpigmented layer. Growth curves indicate this cell population follows a prolonged rate of growth compared to other primary cell cultures. Loss of pigment granules noted by light microscopy were documented by morphometric analysis of electron micrographs. Thirty-two percent of the cultures attempted were successful. Maintenance of these cells in vitro may provide a means for studying their enzyme systems, growth factors, reactions to various stimuli, and the effects of this cell population on other intraocular tissues.

Adolescent↗

Choroidal-ciliary body melanoma. A multivariate survival analysis of tumor location.

BACKGROUND: Posterior uveal melanomas with ciliary body involvement have greater mortality when compared with choroidal melanomas. This study was conducted to determine if this association is due to an independent effect or to correlations with other parameters. METHODS: From the 4335 cases of uveal melanoma with follow-up data in the Registry of Ophthalmic Pathology, 664 were selected; therefore, approximately two thirds of the patients died of metastatic melanoma. Ciliary body involvement was determined by the location of the anterior tumor margin. Kaplan-Meier survival, Cox regression, and Gamel-Boag log-normal regression analyses were performed. Covariables included ciliary body involvement, largest tumor dimension, mean diameter of the largest ten nucleoli, and modified Callender classification. RESULTS: Kaplan-Meier and univariate Cox analyses indicated a significant association between ciliary body involvement and tumor-related death but when included in a multivariate Cox model, ciliary body involvement was not statistically significant. Similarly, when ciliary body involvement was included in a multivariate Gamel-Boag model, ciliary body involvement was not statistically significant. Melanomas that involve the ciliary body were more likely to be larger (Student's t = 10.5; P = 10(-6)), contain larger nucleoli (Student's t = 2.43; P = 0.015), and be of mixed cell type (chi-square = 17.2; P = 3 x 10(-5)). CONCLUSIONS: Ciliary body involvement is associated with tumor-related mortality but this association is primarily due to ciliary body tumors being larger with more malignant cytology.

Choroid Neoplasms↗

The microcirculation of choroidal and ciliary body melanomas.

The microcirculation of ciliary body and choroidal melanomas is remodelled into patterns. The presence of microvascular networks, composed of back-to-back loops that encircle microdomains of tumour, and parallel vessels with cross-linking, are associated with death from metastatic melanoma. The formation of these complex vascular patterns may result from reciprocal interactions between the tumour cell and the extracellular matrix, and pattern formation may reflect an invasive tumour cell phenotype. Ciliary body and choroidal melanomas are among the few forms of cancer treated before a pathologist assigns a grade to indicate whether tumour is likely to follow a benign or aggressive course. There is evidence to suggest that prognostically significant microcirculatory patterns may be detectable by non-invasive imaging techniques that may provide a substitute for biopsy to guide the clinical management of patients with these sight- and life-threatening tumours.

Choroid Neoplasms↗

The inhibition of Na, K-ATPase, and Mg-ATPase by timolol maleate in cultured non-pigmented epithelial cells of the ciliary body.

Bovine, non-pigmented, ciliary body epithelial cells were isolated and grown in culture to determine whether timolol maleate might affect the activity of their plasma membrane ATPases. The possible effects were tested in drug concentrations in a range of 5 x 10(-19) to 5 x 10(-5) M over an incubation period of 30 min at 37 degrees. Assays of specific activity showed that the drug significantly (p less than .001 for most concentrations) inhibited both Na,K-ATPase and Mg-ATPase. However, the inhibition was partially reversed in concentrations greater than 10(-6) M for Na,K-ATPase and 10(-5) M for Mg-ATPase. The latter enzyme also indicated a second partial reversal in activity at concentrations between 10(-12) and 10(-9) M. These reversals in activity suggest that more than one binding site is involved in the inhibition of both enzymes. Since Na,K-ATPase in non-pigmented, ciliary body cells is responsible for the generation of aqueous fluid and the intraocular pressure (IOP), this inhibition demonstrates a possible mechanism for the pharmacological action of timolol maleate in lowering IOP.

Amino Acid Sequence↗

[Dynamic changes of configuration and position of human ciliary body during accommodation].

OBJECTIVE: To study the changes of the configuration and position of ciliary body of normal human eyes in spontaneous far and near accommodations. METHODS: The configuration and position in ciliary body of 68 normal human eyes were observed real-timely and measured by high frequency transducer of ultrasound biomicroscopy (UBM), when these eyes focused on given far and near optotypes, respectively. All of these parameters between far and near accommodations were compared by One-Way Analysis of Variance (One-Way ANOVA) and Multivariate ANOVA of General Linear Model (MANOVA of GLM), and were correlated with each other respectively (alpha=0.05). RESULTS: (1) In near accommodation, there were statistically significant increase in the thickness of anterior ciliary body, length of ciliary process, whole area of ciliary body and area of circular fibers. There were statistically significant decreases in width of ciliary process, angle of inner apex, distances between ciliary process and trabecula, iris, scleral spur, and angles between ciliary process and iris, ciliary process and sclera; there was also a certain decrease in angle-opening distance 500 microm from the scleral spur. There were no significant changes in the thickness of posterior ciliary body; area of meridional fibers; angle between sclera and iris and angle between trabecula and iris. (2) Parameters of configuration had close correlation with each other, and it was also true in those of position. But, the correlation between the configuration and position was not significant. CONCLUSIONS: In the process of near accommodation, ciliary body shifts forwards and inwards, ciliary process becomes tapered because the harmonious contraction of its circular and meridional muscle fibers. This is consistent with the classical relaxation mechanism of accommodation described by Helmholtz. UBM is a new noninvasive method for real-time studying of the ciliary body changes in far-near accommodating human eyes in vivo.

Accommodation, Ocular↗

Plaque radiotherapy of uveal melanoma with predominant ciliary body involvement.

BACKGROUND: There are several options for management of ciliary body melanoma, including plaque radiotherapy, charged particle irradiation, local resection, and enucleation. The choice of therapy depends on many factors, and plaque radiotherapy is often used. OBJECTIVES: To determine the outcome of plaque radiotherapy in the management of ciliary body melanoma and to identify the risk factors associated with the development of radiation complications, tumor recurrence, metastasis, and melanoma-related death after plaque radiotherapy of ciliary body melanoma. METHODS: We analyzed the clinical records of 136 patients with ciliary body melanoma who were treated with plaque radiotherapy between July 1976 and June 1992. RESULTS: The median follow-up period was 70 months. Using Kaplan-Meier survival estimates, the most frequent radiation complication at 5 years' follow-up was cataract, developing in 48% of the patients, followed by neovascular glaucoma (21%), retinopathy (20%), scleral necrosis (12%), and vitreous hemorrhage (11%). Visual acuity decrease (by > or =3 Snellen lines) was noted in 40% of the patients at 5 years. Kaplan-Meier estimates showed that 8% of the patients developed recurrence, 28% had metastasis, and 22% died of melanoma-related causes by 5 years. Univariate analysis demonstrated that the factors predictive of radiation cataract were superonasal (P = .003) and inferior tumor meridian (P = .02) compared with inferonasal meridian and apex dose rate greater than 57 cGy/h (P = .05). The development of neovascular glaucoma was significantly related to iris involvement with the ciliary body tumor (P<.001). The factors predictive of development of radiation retinopathy were base dose rate greater than 230 cGy/h (P = .03) and the presence of diabetes mellitus (P = .05). The only predictor of metastasis was tumor thickness greater than 7 mm (P = .02). The risk factors for melanoma-related death were the presence of metastasis (P<.001), tumor thickness greater than 7 mm (P = .02), and recurrence (P = .02). Multivariate analyses showed that the most significant variables predictive of the development of scleral necrosis were intraocular pressure greater than 15 mm Hg (P<.001) and tumor thickness greater than 7 mm (P = .007). The most significant predictive factors for vitreous hemorrhage were visual acuity of 20/40 to 20/200 (P = .02) and intraocular pressure greater than 15 mm Hg (P = .02). The best subset of independent predictors of vision decrease were mushroom tumor shape (P = .002), age older than 61 years (P = .006), and superonasal meridian (P = .04). The risks for melanoma-related death were presence of metastasis (P<.001) and tumor thickness greater than 7 mm (P = .01). There was no group of significant variables predictive for radiation cataract, neovascular glaucoma, retinopathy, tumor recurrence, and metastasis in multivariate analysis. CONCLUSIONS: Plaque radiotherapy offers 92% 5-year local control rate for ciliary body melanoma. Metastasis occurs in 28% of the patients treated with this method by 5 years. Patients with tumors greater than 7 mm in thickness are at greater risk than patients with thinner tumors for metastatic disease and melanoma-related death. Major radiation complications include radiation cataract, neovascular glaucoma, retinopathy, and scleral necrosis.

Adult↗

[Ultrasound biomicroscopy imaging of accommodative configuration changes in the presbyopic ciliary body].

Direct observation of the position of the ciliary body was possible only in cases of gross anatomic, and probably also functional, abnormalities. Utilizing the 50 MHz ultrasound biomicroscope, we investigated the profile changes of the ciliary body in ten eyes of ten patients, ranging in age from 54 to 86 years while they were ocusing on a target at a distance and afterwards on an object up close. After electronic image processing of ten single video pictures from each accommodative status, a summarized picture for every accommodative status was obtained. In seven of ten cases, during accommodation a remarkable shift of the ciliary body was observed anterior to the iris and in the direction of the lens equatore, while the iridociliary body contact zone became wider in five of the ten eyes. Ultrasound biomicroscopy allows visualization of the dynamics of the accommodative process. As the human ciliary body does not lose its contractility in the senium, the loss of accommodation in presbyopia is mainly caused by age-related changes of the lens and capsula.

Accommodation, Ocular↗

Human ciliary body in organ culture.

Ciliary body explants from 30 human eyes were maintained in organ culture up to 14 days. The age of the donors ranged from 45 to 85 years, the post mortem time from 4 to 22 hours. The ciliary epithelium as well as the underlying stroma were studied light- and electronmicroscopically before incubation and after 1, 3, 5, 7 and 14 days of culture. At the same time intervals, the localization of Na/K-ATPase and carbonic anhydrase (CA) were examined histochemically. If the cells were already damaged before incubation in medium (9 cases), they did not recover in culture. Best results were obtained after 3 to 5 days of culture with a survival rate of more than 90% after 3 days and more than 70% after 5 days, respectively. Both the nonpigmented (NPE) and the pigmented epithelium (PE) of the pars plicata in culture retained the morphological characteristics of epithelia involved in active secretion, namely elaborate infoldings of the cell membranes, numerous mitochondria in the cytoplasm and high activity of Na/K-ATPase and CA. In addition the adjacent capillaries were still fenestrated. After longer incubation times (7-14 days) the NPE and PE cells were filled with increasing amounts of lipid droplets and glycogen granules, indicating changes in metabolism.

Adolescent↗

[A case of pleomorphic adenocarcinoma of the ciliary body].

We performed local resection of a ciliary body tumor, which was diagnosed as pleomorphic adenocarcinoma arising from nonpigmented epithelium of the ciliary body. The patient was a 57-year-old male, and the tumor was found incidentally at an ophthalmologic examination. Since the possibility of malignant tumor could not be ruled out, local resection of the tumor was performed. The tumor developed from the pars plicata and the size was 5.5 x 6.0 x 7.5 mm. Histologically, the tumor cells displayed heteromorphism and revealed tubular and glandular structures which continued to the ciliary body epithelium. Melanin pigment was not observed, except in one small area of the tumor. The interstitium of the tumor tissue was stained with alcian blue, and a immunohistochemical study showed that tumor cells were positive for epithelial membrane antigen (EMA) and vimentin, but negative for S-100 protein and carcinoembryonic antigen (CEA). Electron microscopy revealed desmosomes between cells, and microvilli were observed at the margin of the glandular cavity structure. In this case, no severe complications occurred even after local resection and good visual function was maintained.

Adenocarcinoma↗

Ultrastructural changes in rabbit ciliary body after extraocular mitomycin C.

PURPOSE: To study the ultrastructural changes in ciliary body epithelium of the rabbit eye after subconjunctival injections of mitomycin C. METHODS: One eye of six New Zealand white rabbits was given a subconjunctival injection at the 12-o'clock position with 0.005, 0.02, 0.08, 0.1, 0.12, or 0.16 mg mitomycin C. The fellow eye was given a subconjunctival injection of balanced salt solution. Two weeks after treatment, the eyes were enucleated, and the ciliary body was exposed and submerged in fresh 4% paraformaldehyde/2% glutaraldehyde in 0.1 M phosphate buffer, pH 7.4, at 4 degrees C. Electron microscopy of the ciliary body was performed at two sites: the injection site (12-o'clock position) and 180 degrees away (6-o'clock position). RESULTS: At dosages of 0.1 mg and higher, ciliary body epithelial cells beneath the injection site were thinned. There were vacuoles and expansion of intracellular and intercellular spaces. Plasma membrane infoldings were disrupted, and the apical membrane was thinned. Mitochondria and nuclei were normal. Ciliary body epithelium at 6-o'clock position showed only mild architectural distortion of the plasma membrane infoldings. Eyes that received lower doses of mitomycin C (0.005 mg, 0.02 mg, and 0.08 mg) and balanced salt solution showed normal ciliary body epithelium at the injection site and 180 degrees away. CONCLUSIONS: Subconjunctival injection of mitomycin C in the rabbit produces dose-dependent localized ultrastructural changes of the ciliary body epithelium.

Animals↗

Treatment of intravitreal ciliary body neovascularization.

A patient who developed intravitreal ciliary body neovascularization following cyclocryotherapy for neovascular glaucoma is presented. Presenting vitreous hemorrhage limited her visual acuity to 20/200. After panretinal photocoagulation, the intravitreal ciliary body neovascularization regressed, the vitreous hemorrhage cleared, and the patient's visual acuity was 20/30. The possible pathogenesis of intravitreal ciliary body neovascularization is reviewed, and the reason for regression of the neovascular tissue is hypothesized.

Aged↗

Ring melanoma of the ciliary body: report on twenty-three patients.

BACKGROUND: Ring melanoma of the ciliary body is a rare variant of uveal melanoma that has a poor prognosis. Only isolated cases have been reported in the literature. METHODS: A retrospective review of the clinical features, management, histopathology, and prognosis of 23 consecutive patients with ring melanoma of the ciliary body was performed. RESULTS: Of 8,800 patients with uveal melanoma treated on the Oncology Service at Wills Eye Hospital over a 25-year period, only 23 patients (0.3%) were found to have ring melanoma of the ciliary body. The mean patient age was 59 years (median, 63 years; range, 8-81 years). The only visual symptom was blurred vision in 17 patients (74%), and the other six patients (26%) were asymptomatic. At the initial presentation elsewhere, melanoma was recognized in 13 cases (57%). In the remaining 10 cases (43%), the initial clinical diagnosis was glaucoma in three (13%), iris nevus in three (13%), cataract in two (9%), ciliary body detachment in one (4%), and iridocyclitis in one (4%). The patients were observed elsewhere for a mean of 3 months before the diagnosis of melanoma was suspected and referral to Oncology Service was made. On examination, the tumor involved a mean of eight clock hours of the ciliary body. Seven patients (30%) had complete circumferential (360 degrees) involvement of the ciliary body, and 16 (70%) had incomplete (180-360 degrees) ring involvement. The mean tumor thickness was 8 mm. Associated findings included neovascularization of the iris in one case (4%), shallow anterior chamber in 11 (48%), anterior chamber inflammation in five (22%), cataract in nine (39%), lens indentation in eight (35%), and lens subluxation in three (13%). A prominent episcleral (sentinel) vessel (17 cases, 74%), multilobulation of the mass (19 cases, 83%), blockage of light on transillumination (23 cases, 100%), and ultrasonographic hollowness with intrinsic pulsations (23 cases, 100%) were important features differentiating this tumor from simulating conditions. The tumor was managed with enucleation in all 23 patients. Histopathologic studies revealed epithelioid cell-type melanoma in two patients (9%), mixed cell-type in 17 (74%), and spindle cell-type in four (17%). Extraocular extension was present in eight patients (35%). Metastasis developed in 12 of 23 patients (52%) after a mean follow-up of 55 months. CONCLUSIONS: Ring melanoma of the ciliary body is a rare tumor that can remain hidden from ophthalmoscopic examination. Certain features, such as prominent episcleral sentinel vessels, multilobulation of the mass, light blockage on transillumination, and ultrasonographic hollowness with intrinsic vascular pulsations, suggest the diagnosis. The life prognosis is poor.

Adult↗

[Ultrastructure of leiomyoma of the ciliary body].

Leiomyoma of the ciliary body of the eye was studied with the help of optical microscope at the ultrastructural level. The tumour was characterized by 4 types of cells: micro immature myoblasts, macro differentiated myoblasts, dystrophically changed muscle cells with lipofuscin inclusions, and fibroblasto-like cells. At the luminous level the differentiation of pigmental granules of melanin and lipifuscin was impeded. At the ultrastructural level they had different morphology, and therefore the differential diagnosis of a slightly pigmented melanoma and leiomyoma is possible.

Ciliary Body↗