Biomedical subjects

S P Chee

Publications and source records attributed to S P Chee.

30 records · Page 2Linked to original sources

PubMed1999

Randomized clinical trial of a new dexamethasone delivery system (Surodex) for treatment of post-cataract surgery inflammation.

OBJECTIVE: To evaluate the safety of Surodex Drug Delivery System (Oculex Pharmaceuticals, Inc., Sunnyvale, CA) containing dexamethasone 60 micrograms, for use in cataract surgery, and to compare its anti-inflammatory efficacy with conventional dexamethasone 0.1% eyedrops. DESIGN: Randomized, masked, and partially controlled trial. PARTICIPANTS: Sixty eyes of 60 Asian patients undergoing extracapsular cataract extraction with intraocular lens implantation were examined. Of these, 28 eyes of 28 patients served as control eyes. Patients were stratified for age and presence of diabetes mellitus. INTERVENTION: Surodex was inserted in the anterior chamber of 32 eyes at the conclusion of surgery. These eyes received placebo eyedrops four times a day after surgery for 4 weeks. Control eyes received neither Surodex nor a placebo implant but were prescribed conventional 0.1% dexamethasone eyedrops four times a day for 4 weeks. MAIN OUTCOME MEASURES: Anterior chamber cells and flare were clinically graded at the slit lamp. Anterior chamber flare was objectively assessed with the Kowa FM500 Laser Flare Meter (Kowa Co. Ltd, Tokyo, Japan) for up to 3 months after surgery. Intraocular pressure and corneal endothelial specular microscopy with morphometric cell analysis were performed for up to 1 year after surgery. RESULTS: Clinical slit-lamp assessment of anterior chamber flare and cells showed no difference between Surodex-treated eyes and dexamethasone eyedrop-treated eyes. Flare meter readings showed lower flare levels in the Surodex group at all postoperative visits compared with the dexamethasone eyedrop group. Flare reduction in the Surodex group reached statistical significance at days 4, 8, 15, and 30 after surgery. At 3 months, flare was reduced to preoperative levels in the Surodex group but was still raised in the dexamethasone eyedrop group. Five eyes in the dexamethasone eyedrop group required augmentation of steroids and were deemed therapeutic failures as opposed to one eye in the Surodex group. One patient in the dexamethasone eyedrop group developed postoperative open-angle glaucoma with profound visual field loss and optic disc cupping, resulting in hand movements vision. No significant difference in endothelial cell loss was noted between Surodex-inserted eyes and dexamethasone eyedrop-treated eyes for up to 1 year after surgery. CONCLUSIONS: Intraocular placement of a single Surodex is a safe and effective treatment method to reduce intraocular inflammation after cataract surgery. There was no statistical difference in efficacy between Surodex and 0.1% dexamethasone eyedrops in reducing intraocular inflammation, as measured by clinical methods, while Surodex was clearly superior to eyedrops in reducing aqueous flare as objectively assessed with the laser flare meter.

Aged↗

PubMed1999

Postoperative inflammation: extracapsular cataract extraction versus phacoemulsification.

PURPOSE: To quantitatively compare postoperative inflammation after extracapsular cataract extraction (ECCE) with that after phacoemulsification in an Asian population. SETTING: Singapore National Eye Center, Singapore. METHODS: In this prospective, randomized, double-masked clinical trial, patients having cataract surgery were randomized to receive ECCE (n = 16) or phacoemulsification (n = 18). Diabetics were excluded. Two surgeons performed both types of surgery and implanted a 6.0 mm optic intraocular lens. Inflammation was assessed qualitatively by slitlamp grading of cells and flare and quantitatively using the Kowa flare meter. One independent postoperative investigator performed the slitlamp examination and laser flare meter readings. RESULTS: The ECCE and phacoemulsification groups were comparable (P > .05) in age, sex, ethnicity, and preoperative flare levels. The combined slitlamp inflammatory scores (anterior chamber cells and flare) and mean laser flare meter readings showed the ECCE group had significantly higher mean flare measurements than the phacoemulsification group at days 4 (P = .0012), 8 (P = .0013), 15 (P = .0013), 30 (P = .0004), and 60 (P = .0164). Flare levels in the ECCE group returned to preoperative values by the second month; the phacoemulsification group achieved preoperative levels by 1 month. The clinical inflammatory assessment score correlated closely to the flare level readings. CONCLUSION: Phacoemulsification induced less inflammation than ECCE, with the difference most marked in the first month after surgery.

Aged↗

PubMed1999

The combination of absent thyroid peroxidase antibodies and high thyroid-stimulating immunoglobulin levels in Graves' disease identifies a group at markedly increased risk of ophthalmopathy.

Among Graves' Disease (GD) patients, we have observed an unexpectedly high prevalence of antithyroperoxidase antibody (TPOAb) and antithyroglobulin antibody (TgAb) negativity in those with severe ophthalmopathy. To study the possible role of thyroid autoantibodies in the pathogenesis of Graves' ophthalmopathy (GO), TPOAb, TgAb, thyroid-stimulating immunoglobulin (TSI), and thyrotropin-binding inhibitory immunoglobulin (TBII) levels were measured, and the presence or absence of GO was assessed by a single observer in 100 consecutive patients with newly diagnosed, untreated GD who were nonsmokers. Ophthalmopathy was present in 43 patients. TSI levels (p = 0.001), and the prevalence of TPOAb-negativity (p = 0.002) were significantly higher in patients with ophthalmopathy compared to those without. Logistic regression analysis showed that TSI levels (p = 0.005) and the absence of TPOAb (p = 0.0025) were independent predictors of GO. No correlation between TBII or TgAb and eye disease was found. The prevalence of GO increased with each quartile of TSI levels. The prevalence was 20%, 36%, 52%, and 64% in the first, second, third and fourth quartiles of TSI, respectively. The odds ratio of GO (with 95% confidence intervals) when TSI levels were above the median level (1640%) was 3.6 (1.5-8.0), when TPOAb was negative it was 5.0 (1.7-14.4), and with both risk factors it was 36.6 (4.3-313.5). The prevalence of ophthalmopathy in this last group was 92.9%. The combination of negative TPOAb and high TSI levels appears to be associated with a markedly increased risk of clinically evident ophthalmopathy.

Adult↗

PubMed1998

Refractive change following pterygium surgery.

PURPOSE: We conducted a prospective study of patients with primary pterygia to analyze surgically-induced astigmatic changes following pterygium surgery and their relation to pterygium morphology and size. METHODS: One hundred twenty-three eyes of 123 adult patients with primary pterygia were evaluated. Pterygium was graded according to morphology and the extent of corneal encroachment. Manifest refraction was performed preoperatively and at 1, 3, and 6 months postoperatively. Patients underwent either the bare sclera technique of pterygium excision or conjunctival grafting. Surgery was performed by one surgeon. Olsen's method of vector decomposition was used to analyze surgically-induced astigmatism. RESULTS: The mean magnitude of preoperative astigmatism was 0.99 D, with vector decomposition revealing a relative flattening of the cornea in the horizontal meridian. Astigmatism of 1.00 D or more was seen when the pterygium exceeded 3.5 mm beyond the limbus. Postoperatively, a steepening of the cornea in the horizontal meridian was demonstrated, the magnitude of which was related to pterygium size (P = 0.0001). ANOVA testing showed no significant difference (P > 0.05) when pterygia were divided according to morphology. CONCLUSIONS: This study confirms that pterygium excision induces a reversal of pterygium-related corneal flattening. A strong correlation was also found between the horizontal extent of pterygium encroachment and astigmatic change following surgery.

Adult↗

PubMed1998

A case series of ocular disease as the primary manifestation in sarcoidosis.

Sarcoidosis is an idiopathic, systemic, non-caseating, granulomatous disease with protean clinical manifestations. This disease is highly prevalent in the southern states of United States of America, especially among African-Americans, but uncommon among Asians. Though sarcoidosis concerns physicians of virtually all specialties, it is particularly important to ophthalmologists since a significant number of patients will seek initial medical examination because of ocular disease. Out of the 262 cases of uveitis examined at the Singapore National Eye Centre over a period of two years, 9 cases were diagnosed as sarcoidosis. We report here 4 patients with active sarcoidosis who presented to us with ocular symptoms as the first and primary manifestation of the disease. All 4 patients developed symptoms and signs of systemic sarcoidosis at a later date. The ocular manifestations included simultaneous bilateral chronic granulomatous iridocyclitis, intermediate uveitis, posterior uveitis characterised by vasculitis with candle wax drippings, and optic nerve head granuloma.

Adult↗

PubMed1997

Effect of pterygium morphology on pterygium recurrence in a controlled trial comparing conjunctival autografting with bare sclera excision.

OBJECTIVES: To compare success rates of conjunctival autografting and bare sclera excision for primary and recurrent pterygium in the tropics and to evaluate risk factors for pterygium recurrence. METHODS: A prospective, controlled clinical trial was performed in which 123 primary and 34 recurrent pterygia, matched for age and pterygium morphology, were randomized in 2 separate studies to receive either bare sclera excision or conjunctival autograft. The surgical procedures were performed by one surgeon and reviewed at 1, 3, 6, and 12 months after surgery by an independent observer. Pterygium morphology was clinically graded as atrophic, intermediate, or fleshy according to an assessment of pterygium translucency. Risk factors were assessed using likelihood ratio tests. Weibull curves were used to estimate recurrence rates allowing for the interval censoring. RESULTS: In the group with primary pterygium (mean follow-up, 15.1 months), 38 (61%) of the 62 cases of bare sclera excision (heretofore referred to as the bare sclera group) had pterygium recur in contrast with 1 (2%) of the 61 cases of conjunctival autograft (heretofore referred to as the conjunctival autograph group) (P<.001, likelihood ratio X2 test). Nontranslucency, or fleshiness of the pterygium, and not age was a significant risk factor for recurrence in the bare sclera group (P<.001, likelihood ratio X2 test). In the group with recurrent pterygium (mean follow-up, 13.2 months), 14 (82%) of the 17 bare sclera group had pterygium recur, while no recurrences occurred among 17 cases in the conjunctival autograft group. Nontranslucency was again a highly significant factor for recurrence (P<.001, likelihood ratio X2 test). CONCLUSIONS: Pterygium recurrence is related to pterygium morphology and fleshiness of the pterygium is a significant risk factor for recurrence if bare sclera excision is performed. Conjunctival autografting for primary and recurrent pterygium is effective in reducing pterygium recurrence compared with bare sclera excision.

Adult↗

PubMed1996

Infections of the eye.

Infections of the eye range from the mild to the severe. They may affect the lid, conjunctiva, cornea, lacrimal apparatus, vitreous, orbit or retina. Common presentations, diagnostic methods and treatment are briefly described. The doctor should not only manage outpatients appropriately, but know when to seek the advice of the ophthalmologist when indicated. Common conditions which can be managed by the general practitioner include blepharitis, styes, chalazia and conjunctivitis. With increased use of contact lenses, infection of the cornea has become more common. Sight-threatening conditions like endophthalmitis and orbital cellulitis should be recognised and treated early.

Eye Infections↗

PubMed1996

Sebaceous carcinoma of the eyelids: a review of six cases.

Sebaceous carcinoma of the eyelid, although rare, carries a grave prognosis when diagnosed late. It may be mistaken by the unsuspecting ophthalmologist for a chalazion or chronic blepharoconjunctivitis. Six cases are presented. Three patients were in their fifth decade and the remaining three were over seventy. The latter group presented with advanced local disease and had poorly differentiated tumours. The two oldest patients died of metastasis within 54 months of presentation despite total excision of the lid tumour. This review demonstrates the problems encountered in diagnosis and management.

Adenocarcinoma, Sebaceous↗

PubMed1995

Endogenous Klebsiella endophthalmitis--a case series.

Nine eyes of 7 patients with endogenous Klebsiella endophthalmitis are presented. Five patients were diabetic and 4 had sepsis arising from the hepatobiliary system, one from the urinary tract and another from the lung. The most classical sign of pupillary hypopyon was present in 5 eyes. Five eyes were initially misdiagnosed and treated as inflammatory uveitis. Five eyes finally had no light perception, one eye had 6/60, another had 6/36 and two eyes of one patient recovered 6/6 vision. The successful outcome of this patient achieving 6/6 vision in either eye can be partly attributed to an early diagnosis and appropriate management. A high index of suspicion may improve visual outcome in such cases.

Adult↗

PubMed1993

Early central posterior capsular fibrosis in sulcus-fixated biconvex intraocular lenses.

A series of 228 eyes implanted with one-piece all poly(methyl methacrylate) (PMMA) biconvex posterior chamber intraocular lenses was examined for posterior capsule opacification. One hundred forty-one eyes (61.8%) had opacification at an average postoperative period of 19.7 months. Seventy eyes (30.7%) developed an unusual form of early central posterior capsular fibrosis (ECPCF), which was confined to the capsulorhexis opening, sparing the peripheral aspect of the anterior and posterior capsules. Risk factors for developing this form of opacification were close apposition of peripheral anterior and posterior capsules caused by placing a posteriorly vaulted biconvex optic anterior to a capsulorhexis opening smaller than the optic diameter. This opacification occurred most often in cases of haptic fixation in the ciliary sulcus. The cumulative capsulotomy rate in this series was 5.26% at three months, 9.1% at 12 months, and 13.2% at 20 months. Of the ECPCF cases, 34.3% eventually required neodymium: YAG (Nd:YAG) laser capsulotomy; the capsulotomy rate for ECPCF was 4.8 times higher than that for Elschnig pearls. Early onset of ECPCF (average onset = 19.4 weeks) resulted in early Nd:YAG capsulotomy (average = 8.0 months after surgery). One-piece all-PMMA biconvex intraocular lenses may promote early central fibrosis of the posterior capsule if the lens optic is anterior to a capsulorhexis opening smaller than the optic diameter. The early onset of this form of opacification predisposes to earlier Nd:YAG capsulotomy with a higher risk of complications.

Adult↗

PubMed1993

Progressive optic atrophy associated with juvenile diabetes mellitus: report of two cases among first cousins.

Two first cousins both suffering from insulin dependent diabetes mellitus since early childhood developed progressive optic atrophy from the age of 5 and 9 years respectively. They had similar ophthamological features which include optic atrophy with cupping, paracentral scotomata, and total achromatopsia. One patient also had stunted growth, delayed puberty and psychiatric disorder. Neither had diabetes insipidus and deafness. It is suggested that they may be a variant of DIDMOAD (Diabetes Insipidus, Juvenile Diabetes Mellitus, Optic Atrophy, Deafness).

Adolescent↗

PubMed1992

Anti-toxoplasma serotitres in uveitis and ocular toxoplasmosis.

This study was based on anti-toxoplasma serotitres obtained from 80 normal healthy adults and 103 consecutive patients with anterior, posterior and panuveitis over a 42 month period. Twelve out of 80 (15%) normal healthy sera were found to have low titres (1:64 to 1:256), while 3 (3.8%) had high titres (1:1024 or higher). The distribution of serotitres in patients with clinical toxoplasmosis was significantly different from the population sample (p less than 0.001, chi-squared test). Similarly, the distribution of serotitres in patients with posterior uveitis (of which 28 out of 54 were clinically ocular toxoplasmosis) having serotitres of 1:1024 or greater, was found to be significantly different from the normal population (p less than 0.001, Chi-squared test), but not statistically different from those with clinical ocular toxoplasmosis. Hence, anti-toxoplasma serotitre is useful as a diagnostic screening tool only in patients with posterior uveitis. It is also useful in confirming cases of suspected clinically positive ocular toxoplasmosis in our local population.

Adolescent↗