Biomedical subjects

V S Yong

Publications and source records attributed to V S Yong.

11 recordsLinked to original sources

PubMed2001

Herpes zoster ophthalmicus and the superior orbital fissure syndrome.

Herpes Zoster Ophthalmicus (HZO) is not an uncommon condition in the elderly and the immunocompromised. The common ocular manifestations include blepharoconjunctivitis, keratitis and uveitis. Dramatic presentations like orbital apex syndrome and superior orbital fissure syndromes occur rarely in patients with herpes zoster meningo-encephalitis. We report a patient with herpes zoster meningo-encephalitis and the superior orbital fissure syndrome (SOFS).

Anisocoria↗

PubMed2000

Subjective visual experience during phacoemulsification and intraocular lens implantation under topical anesthesia.

OBJECTIVE: The aim of this study was to investigate the subjective visual experience of patients during phacoemulsification and intraocular lens (IOL) implantation under topical anesthesia. DESIGN: Postoperative questionnaire survey. PARTICIPANTS: The study cohort consisted of 52 patients with cataracts. There were 18 male (34.6%) and 34 female (65.4%) patients. Their mean (+/- SD) age was 67.5 (+/-10.8) years. INTERVENTION: The patients underwent routine phacoemulsification and IOL implantation under topical anesthesia. MAIN OUTCOME MEASURES: The patients were interviewed on the same day after their operation regarding their visual experience in the operated eye during surgery. RESULTS: All patients (100%) reported that they could see at least some light during the surgery. Some patients reported they could also see one or more colors (50 patients, 96.2%), movements (32 patients, 61.5%), flashes (24 patients, 46.2%), the surgeon's fingers/hands (13 patients, 25%), instruments (12 patients, 23.1%), and/or the surgeon (4 patients, 7.7%). The colors seen included red (24 patients, 46.2%), yellow (23 patients, 44.2%), blue (12 patients, 23.1%), green (7 patients, 13.5%), and orange (6 patients, 11.5%). Eight patients (15.4%) saw the spectrum of colors similar to that of the rainbow. Twenty-four patients (46.2%) reported that the brightness of light changed during the course of the operation. Eight patients (15.4%) found their visual experience frightening. There was no statistically significant association between those who found the visual experience frightening and the sex or age of the patient, a history of cataract operation in the fellow eye, the type of visual sensation experienced, or the presence of coexisting ocular pathology. CONCLUSION: All patients undergoing phacoemulsification under topical anesthesia experience a variety of visual sensations that may be frightening in a small proportion of patients.

Aged↗

PubMed2000

Subjective visual experience during phacoemulsification and intraocular lens implantation using retrobulbar anesthesia.

PURPOSE: To investigate the subjective visual experience of patients during phacoemulsification and intraocular lens (IOL) implantation using retrobulbar anesthesia. SETTING: Department of Ophthalmology, Tan Tock Seng Hospital, Singapore. METHODS: Seventy cataract patients who had routine phacoemulsification and posterior chamber IOL implantation under retrobulbar anesthesia were interviewed on the day of their surgery regarding their visual experience in the operated eye during surgery. Thirty-nine men (55.7%) and 31 women (44.3%) were included in the study. Their mean age was 65.1 years (range 37 to 87 years). Preoperative best corrected visual acuity ranged from 6/12 to counting fingers. Sixty eyes (85.7%) had no ocular pathology other than cataract. Eleven patients (15.7%) reported no light perception during the surgery. The rest reported they could see light (59 patients, 84.3%), 1 or more colors (39 patients, 55.7%), flashes (35 patients, 50.0%), movements (34 patients, 48.6%), instruments (12 patients, 17.1%), and the surgeon's fingers or hands (11 patients, 15.7%). The colors seen included red (23 patients, 32.9%), blue (17 patients, 24.3%), yellow (12 patients, 17.1%), green (7 patients, 10. 0%), and orange (1 patient, 1.4%). Eight patients (11.4%) saw a spectrum of colors similar to a rainbow. Thirty-one patients (44.3%) reported that the brightness of light changed during surgery. Five patients (7.1%) found their visual experience frightening. Patients who reported seeing colors (P =.048, Fisher exact test) and flashes of light (P =.027, Fisher exact test) were more likely to find the experience frightening. There was no statistically significant correlation between those who found the experience frightening and patient sex or age, length of surgery, or history of cataract surgery in the fellow eye. CONCLUSIONS: Many patients having phacoemulsification and IOL implantation under retrobulbar anesthesia experienced a variety of visual sensations that were frightening in a small proportion of cases.

Adult↗

PubMed1999

Subjective visual experience during extracapsular cataract extraction and intraocular lens implantation under retrobulbar anaesthesia.

PURPOSE: To investigate the subjective visual experience of patients during cataract surgery under retrobulbar anaesthesia. METHODS: One hundred cataract patients who underwent routine extracapsular cataract extraction and intraocular lens implantation under retrobulbar anaesthesia were interviewed by the authors on the same day after their operation regarding their visual experience in the operated eye during surgery. RESULTS: Forty-three men and 57 women were included in the study. Their mean age was 68.4 years (range 40-87 years). Their pre-operative best corrected visual acuity ranged from 6/12 to perception of light. Eighty-four eyes had no other ocular pathology apart from cataract. Twenty patients reported no light perception during the surgery. The rest reported that they could see light (80 patients), one or more colours (56 patients), movements (39 patients), flashes (36 patients), instruments (16 patients) and/or the surgeon's fingers or hands (10 patients). The colours seen included red (29 patients), yellow (29 patients), green (12 patients), blue (11 patients) and orange (2 patients). Fifteen patients saw a spectrum of colours similar to that of the rainbow. Forty-four patients reported that the brightness of light changed during the operation. Five patients found their visual experience frightening. There was no correlation between those who found the experience frightening and the sex or age of patient, presence of coexisting ocular pathology, duration of operation, whether the operation was the first or second cataract operation in the patient, or the type of visual sensation experienced. CONCLUSION: Many patients undergoing cataract surgery under retrobulbar anaesthesia experience a variety of visual sensations that may be frightening in a small proportion of cases.

Adult↗

PubMed1999

Management of subluxated crystalline lenses with planned intracapsular cataract extraction and anterior chamber intraocular lens implantation.

PURPOSE: To review the visual and surgical outcome of planned intracapsular cataract extraction (ICCE) and anterior chamber intraocular lens (AC IOL) implantation for subluxated crystalline lenses. METHODS: Eight eyes of 7 patients with subluxated lenses which underwent planned ICCE, AC IOL implantation and peripheral iridectomy by one surgeon between September 1995 and November 1996 were prospectively followed-up to ascertain their visual and surgical outcome. RESULTS: There were 4 male and 3 female patients. Their mean age was 64.4 years (range, 39-86 years). Seven lenses were removed by cryoextraction while one was removed with the aid of a vectis. The mean post-operative follow-up was 11.6 months, (range, 3-22 months). Excluding 1 eye with pre-existing ocular pathology, all eyes achieved a best corrected visual acuity (BCVA) of 6/12 or better post-operatively. One of these eyes, in a schizophrenia patient, developed subluxation of the AC IOL and retinal detachment 11 months after the cataract surgery due to repeated eye rubbing. The final BCVA became 6/120 after successful repositioning of the AC IOL and retinal re-attachment surgery. One eye achieved a BCVA of 6/36 due to age-related macular degeneration. CONCLUSION: Our results show that planned ICCE and AC IOL implantation is a useful and safe procedure in the management of subluxated lenses.

Adult↗

PubMed1997

Iris varix.

Varix of the iris as a solitary primary lesion is rare. We report a 31-year-old Indian man with an iris varix who developed recurrent haemorrhages into the anterior chamber which led to secondary glaucoma. An iridectomy was performed and the diagnosis was confirmed histologically. There has been no recurrence of the lesion 3 years after surgery.

Adult↗

PubMed1997

Pseudomyopia in a patient with blocked ventriculo-peritoneal shunt--a case report.

Accommodative spasm usually encompasses a classical triad of pseudomyopia, esodeviation and pupillary constriction. Accommodative spasm is most often psychogenic in nature; however, it may be associated with other organic diseases of which a rare cause is that of intracranial catheter complications. We report a case of dorsal midbrain syndrome with pseudomyopia in a patient with a blocked ventriculo-peritoneal shunt inserted for aqueductal stenosis. Clinical presentation was unusual in this patient as pseudomyopia occurred with exodeviation and without pupillary constriction.

Adult↗

PubMed1997

Idiopathic intracranial hypertension, empty sella turcica and polycystic ovary syndrome--a case report.

Permanent visual loss is a well established major sequela of idiopathic intracranial hypertension (IIH). It is often insidious and frequently unnoticed by patients with IIH. It is vital to monitor these patients with serial perimetric and visual acuity tests because visual loss can be halted and occasionally reversed if treatment is begun early. We report a case of IIH with an empty sella turcica and polycystic ovary syndrome who developed visual field loss over ten years. This report illustrates the importance of close ophthalmic monitoring and detailed neurological and endocrinological evaluation to prevent complications in such patients.

Adult↗

PubMed1991

Singapore General Hospital's experience in corneal grafting.

This is a retrospective study of 56 corneal grafts that was done in the Singapore General Hospital (SGH) between 1980 and 1989. These cases were analysed and it was found that there was a male predominance of about 2:1. There was a rather even spread among the various age groups except for a slightly higher incidence in the 20-29 year age group. There was a drastic drop in the number of grafts done after the year 1987 and this was attributed to the reluctance to accept donor corneas from Sri Lanka as there was the danger of the AIDS transmission through the donor material. The most number of grafts were done for patients with infection as a cause for corneal opacities, followed closely by keratoconus. There was a high incidence of graft rejection as almost 20 out of the 56 developed rejection. However, the visual results proved to be good with 27 obtaining at least 6/12 vision post operatively. This article outlines the need for more stringent pre-operative evaluation of both the donor material as well as the host patient in order to reduce the incidence of graft rejection and, hence, increase the overall success rate.

Age Factors↗

PubMed1990

Multifocal intraocular lens: a new development in aphakic visual rehabilitation.

Multifocal intraocular lenses have been in the market for three to four years. They were designed to achieve bifocal effect, minimising the need for additional spectacle correction for near vision. This is a retrospective analysis of visual results in one hundred and four eyes implanted with multifocal intraocular lenses. They were followed up for two months to one year. The results showed that 95 eyes (93%) achieved best corrected distant visual acuity of 6/6-6/12; 99 eyes (97%) achieved near visual acuity of N5-N6; 92 eyes (90%) achieved their best near vision with their distant correction, not requiring further refractive correction for near. The selection of patients was done at random. Two patients were excluded from the analysis due to macular degeneration. The quality of vision was not assessed in this study.

Adult↗

PubMedDate not supplied

A novel approach for the fixation of enucleated eyes during microsurgical procedures using common household plumbing accessories.

The authors describe a novel approach for the fixation of enucleated eyes during microsurgical procedures using common household plumbing accessories. The device consists of a ring adaptor with 4 round-ended screws placed horizontally at its sides and a plastic hose connector. The enucleated globe is secured in the center of the ring adaptor by gently tightening the screws. The hose connector supports the posterior pole of the globe and is secured onto a styrofoam board that provides a platform for resting the surgeon's hands. The device proved very satisfactory to residents during the teaching of cataract surgery and trabeculectomy on porcine eyes. Our globe fixation device is simple, inexpensive, effective, and readily available. It may be especially useful in developing countries.

Equipment Design↗