Conjunctival concretions. Polarized microscopic, histopathologic, and ultrastructural studies.

To elucidate the pathophysiologic features of conjunctival concretions, we performed polarized microscopic examinations, immunocytochemical studies, histochemical stains, and electron microscopic studies of concretions obtained from five patients with chronic conjunctivitis. Electron-dense secretory granules, ranging from 0.2 to 0.5 micron in diameter and stained positively for periodic acid-Schiff and mucicarmine, were found in the superficial lining epithelial cells of the pseudogland of Henle. In view of the granular and membranous figures reflecting degenerating epithelial cells and secretory granules in the concretions, we argue that the concretions, are mostly composed of the mucinous secretion of the transformed conjunctival glands admixed with the degenerative products of the epithelial cells.

Cytogenetic evidence of multifocal origin of a unilateral retinoblastoma. A help in genetic counseling.

Retinoblastoma (Rb) occurs in two different genetic forms, hereditary and nonhereditary. Patients with nonhereditary Rb have unilateral, unifocal tumors, and those with the hereditary form usually have bilateral, multiple tumors. However, about 15% of patients with unilateral disease actually have multifocal tumors due to the hereditary form of Rb. Distinction between unilateral hereditary and sporadic Rb is very important both to the patient, who is at risk of later development of other malignancies, and to any future siblings and offspring. With only clinical data, the discrimination may be difficult. The cytogenetic detection of multiple unrelated clones in the tumor is very helpful for differential diagnosis because this finding strongly suggests the presence of a prezygotic germ cell mutation, which is heritable. A 23-month-old Chinese boy was found to have a single retinoblastoma at the right eye. Cytogenetic study of the tumor cells revealed three abnormal clones. Two of them were related, but the third one had completely different markers, suggesting a hereditary, multifocal origin of the tumor. None of the three clones showed an abnormality of 13q, which is present in about 21% of all Rb patients.

Corneal epithelial recovery following photorefractive keratectomy.

AIMS: To further understand the morphological and functional recovery of corneal epithelium following excimer laser photorefractive keratectomy (PRK). METHODS: The right eyes (group 1) of 15 male, New Zealand white rabbits weighing 2-3 kg underwent PRK. The left eye of each rabbit (group 2) underwent simple mechanical de-epithelialisation and were examined as treated controls. Both eyes of another eight rabbits (group 3) served as untreated controls. All eyes underwent a corneal epithelial permeability study by fluorophotometry at 2, 4, and 8 weeks after surgery. Five animals in groups 1 and 2 were sacrificed at 9, 10, and 12 weeks after surgery. The animals in group 3 were sacrificed at the end of the 12 week experimental period. Both eyes of each sacrificed animal were enucleated immediately and processed for both haematoxylin and eosin stain and electron microscopic study. The electron micrograph was magnified to 14,000x and the extent of hemidesmosome formation was quantified and analysed. RESULTS: The corneal epithelial barrier to sodium fluorescein was subnormal and returned to a normal barrier state 4 weeks after PRK in group 1 whereas it was normal in group 2 throughout the examination period. The extent of hemidesmosome formation was abundant yet subnormal in both groups 1 and 2 up to 12 weeks, when compared with that in group 3. CONCLUSION: The corneal epithelium regained its functional barrier 4 weeks after PRK in rabbits while the extent of hemidesmosome formation was still subnormal 12 weeks after mechanical de-epithelialisation, with or without PRK.

Transcaruncular approach for the management of frontoethmoid mucoceles.

AIMS: To present transcaruncular medial orbitotomy as the preferred approach to manage frontoethmoid mucoceles. METHODS: 11 patients with frontoethmoid mucoceles received transcaruncular orbitotomy from 2000 to 2002 at the National Taiwan University Hospital. The incision was made through the caruncle to explore the medial wall periosteum. Then the periosteum was opened and extended to provide adequate surgical field exposure. Frontoethmoid mucoceles could be viewed and removed directly. A transnasal drainage tube was inserted before closure of the caruncle wound. RESULTS: The mean follow up period was 12 (SD 9.1) months (range 1-26). Both functional recovery and cosmetic outcome were excellent. There was no recurrence of mucoceles. One patient complained of diplopia, which subsided after 2 months. CONCLUSION: Transcaruncular orbitotomy provides a wide exposure and a safe access to the medial orbital extraperiosteal space. Furthermore, there is less damage to skin and muscle layer and less manipulation of other ocular adnexal structures, such as medial canthal tendon and lacrimal sac. It can be an excellent approach for the management of frontoethmoid mucoceles.

Results of intraoperative mitomycin C application in dacryocystorhinostomy.

AIMS: To evaluate the long term results of intraoperative mitomycin C application in dacryocystorhinostomy (DCR) surgery compared with results of the conventional procedure. METHODS: In this prospective randomised controlled study, a total of 88 eyes diagnosed with acquired nasolacrimal duct obstruction were randomly divided into a conventional DCR group and a mitomycin C group in which mitomycin C was used during DCR surgery. The surgical procedures in both groups were exactly the same, except that in the patients in the mitomycin C group, a piece of neurosurgical cottonoid soaked with 0.2 mg/ml mitomycin C was applied to the osteotomy site for 30 minutes. The results of the DCR surgeries were evaluated by objective findings such as irrigation and the height of tear meniscus and subjective symptoms by asking patients the condition of tearing improvement. RESULTS: Among the 44 eyes in the mitomycin C group, 95.5% of patients remained totally symptom free after 10 months of follow up; while in the conventional group, 70.5% of patients were reported to be symptom free and 18% of patients to have an improvement in their symptoms. There was a significant difference between these two groups. As far as objective findings were concerned, there were 41 eyes in the mitomycin C group classified as having a normal and one eye with moderate tear meniscus level, compared with 32 eyes and seven eyes, respectively, in the conventional group. There was also a significant difference between these two groups. The non-patency rate in the mitomycin C group is 4.5% compared with 11.4% in the conventional group. There were no complications such as abnormal nasal bleeding, mucosal necrosis, or infection except one patient with delayed wound healing. CONCLUSIONS: Intraoperative mitomycin C application is effective in increasing the success rate of DCR surgery in standard nasolacrimal duct obstruction, and no significant complications resulted from its use.

Complications of motility peg placement for porous hydroxyapatite orbital implants.

AIM: To evaluate the complications associated with pegging of porous hydroxyapatite orbital implants. METHODS: Complications associated with pegging were retrospectively reviewed from the charts of 100 of 133 patients with hydroxyapatite implantation from 1993 to 2000. RESULTS: 48 (48%) of the 100 hydroxyapatite implanted patients who had undergone pegging were found to have problems with their pegs, including discharge (45.8%), peg falling out (20.8%), pyogenic granulomas (16.7%), popping peg (14.6%), hydroxyapatite visible around peg hole (8.3%), part of peg shaft visible (6.2%), peg drilled off centre (6.2%), peg drilled at an angle (4.2%), and excess movement of peg (4.2%). The standard peg fell out statistically more often than the peg and sleeve system (Yates's corrected chi(2), p=0.038). There was a trend towards complications of the peg with use of a standard peg (versus sleeved peg) (p=0.226). CONCLUSIONS: There are several potential complications of pegging. Most complications are minor and can be managed successfully.

Choroideremia: a study of two families.

Choroideremia is a bilateral and progressive chorioretinal degenerative disease of X-linked inheritance. In Taiwan, the disease has rarely been reported. We recently found 8 male patients and 5 female carriers in two Chinese families with choroideremia and studied the clinical, psychophysical and electrophysiological properties of the disease. All patients revealed characteristic fundus and fluorescein angiographic changes in retinal pigment epithelium, and choroidal atrophy of variable extent. The severity of the functional impairments paralleled the fundus changes and the patients' age. However dark adaptation and the visual field were affected earlier than visual acuity and color sensation. In addition, rod cell impairment was found to be more severe than cone cell impairment in the electroretinographic studies. On the other hand, all carriers revealed similar diffuse punctate pigmentary changes and only mild abnormalities in dark adaptation. These findings may suggest that in choroideremia patients the photoreceptor cells are very sensitive to the influence of the choroidal atrophy, and that rod cells may be even more vulnerable than cone cells.

Surgical management of Graves' ophthalmopathy: stage I, inferomedial orbital decompression.

Inferomedial orbital decompression was done on 26 eyes with dysthyroid optic neuropathy (DON), seven eyes with corneal exposure which had not responded to topical lubricants, and six with disfiguring exophthalmos. Twenty-one of the 26 DON eyes (80.7%) had visual acuity improvement equal to or greater than two lines by the Snellen chart, and there was only one in all 39 eyes that dropped more than two lines. The average retinal sensitivity improvement was of borderline significance (4.25 +/- 5.73 dB), but for those 13 severely affected eyes (preoperative sensitivity loss > or = 10 dB), 11 (84.6%) of them showed significant improvement. There were 16 bilateral and seven unilateral cases. Out of all 39 eyes, the average retroplacement effect was 4.6 +/- 2.3 mm, and none of them had postoperative asymmetry greater than 2 mm by Hertel's exophthalmometry. Although the palpebral fissure height tends to remain the same after surgery, upper lid retraction is likely to be worse. The most frequent sequela was diplopia, which tended to occur in more severely myopathic eyes regardless of the surgical approach used. Although a staged approach is mandatory in surgical treatment of this disorder, individualization of surgical goals and intraoperative titration of the retroplacement effect are of equal importance for optimal results.

Staged operation for Graves' ophthalmopathy.

A four-staged operation is currently the most effective treatment available in the management of stable Graves' ophthalmopathy. This report describes the results of four-staged therapy in 51 patients with Graves' ophthalmopathy. Stage I, orbital decompression: 58 orbits in 32 patients underwent orbital decompression, with an average retroplacement effect of 4.2 +/- 2.2 mm (mean +/- SD). This procedure is effective to restore vision and correct the proptosis due to Graves' ophthalmopathy. Careful intraoperative titration of the retroplacement effect during orbital decompression is very important to achieve successful results. Stage II, strabismus surgery: 24 patients underwent strabismus surgery, including 11 with previous decompression surgery and six with previous simultaneous decompression and strabismus surgery. The overall success rate was 87% and previous decompression or strabismus surgery had no influence on the final results. Stage III, fissure width adjustment: 28 patients (45 eyes) received fissure width adjustment. Various procedures were performed and we found Müllerectomy with levator muscle stripping to be the most useful procedure for fissure width adjustment. The average improvement of fissure height was 3.1 +/- 1.8 mm. The rate of overall satisfactory results was 89%. There were five patients who received Staged IV cosmetic procedures with satisfactory results. Graves' ophthalmopathy is a chronic disease that needs thorough cooperation between doctor and patient. Careful evaluation of clinical parameters and individualized surgical goals are the keys to success.

Laser flare-cell meter analysis of blood-aqueous barrier functional status in a patient with crystalline retinopathy.

This is the first report in the literature of the application of a laser flare-cell meter to examine the functional status of the blood-aqueous barrier in a patient with crystalline retinopathy. The patient, a 34-year-old man with typical crystalline retinopathy, had crystal deposits scattered throughout the posterior pole of the fundus in both eyes. Fluorescein angiography showed atrophy of the retinal pigment epithelium and geographic areas of choriocapillaris atrophy in the posterior pole. Electroretinography showed subnormal amplitude, and the light-peak/dark-trough ratio of the electrooculogram was reduced. Laser photometry showed an increase in the aqueous flare intensity in both eyes, compared with normal values obtained from healthy control subjects. The increase in the aqueous flare intensity in this patient indicates that the function of the blood-aqueous barrier might have been affected in crystalline retinopathy.

Relapse of acute leukemia in childhood presenting as proptosis due to an orbital mass.

Extramedullary relapse of acute leukemia in sites outside the central nervous system or testes is rare. We report two children who developed proptosis due to an orbital mass as the initial presentation of leukemic relapse. The first patient was an 11-year-old girl with acute myelogenous leukemia who had undergone bone marrow transplantation 4 years previously. She had been in remission until 2 months prior to the present admission, when she developed isolated relapse of disease in the left orbit. The second patient, an 11-year-old girl with acute lymphoblastic leukemia, had been off chemotherapy for 2 years and in remission for 5 years. She suffered from concurrent orbital and central nervous system relapse. Both patients were treated with systemic chemotherapy and orbital radiotherapy. More than 1 year after the relapse, the proptosis was completely cured in both patients.

Vitreous fluorophotometry in patients with crystalline retinopathy.

Patients with various stages of crystalline retinopathy were examined with vitreous fluorophotometry and the results were compared with those of normal subjects. Two patients with glistening crystals without pigment clumps, together with atrophy of the retinal pigment epithelium in the posterior pole, showed a normal inward permeability of fluorescein. Three patients with a large area of choriocapillaris atrophy in the posterior pole, in addition to atrophy of retinal pigment epithelium, demonstrated an increase in the rate of inward fluorescein penetration. Three patients with extensive areas of choriocapillaris atrophy throughout the fundus also revealed an increased posterior vitreous penetration ratio.

The effects of Qi-Qong ocular exercise on accommodation.

Visual-training methods in management of myopia are suggested as possibly leading to normal vision or an improvement in the refractive state. The purpose of this work was to investigate the hypothesis that a Qi-Qong ocular exercise improves visual function by training the accommodation bias. Variations of pupil size, accommodative amplitude, latency and speed of accommodative response and accommodative adaptation were evaluated objectively. The accommodative state was monitored with an objective infrared refractometer (Nidek AA-2000). Subjects were divided into two groups: experimental (n = 9), and control (n = 8). Subjects of the experimental group undertook the Qi-Qong ocular exercise for at least three years, and were able to perform the exercise smoothly and gently. Subjects of the control group had no knowledge of the Qi-Qong ocular exercise, but were given the same testing procedures as the experimental group. Results showed that Qi-Qong ocular exercise can improve the accommodative amplitude and accelerate the accommodative response slightly, but there was no effect on the latency of accommodative response. Furthermore, the level of accommodative adaptation was elevated, and the pupil became slight miotic. Therefore, the mechanism of visual improvement may undergo a great accommodative adaptation and produce a pinhole effect by miosis of the pupil. Methods of visual training can produce a false image of visual improvement from an enhanced parasympathetic response to a task, but this effect may be a factor that induces progression of myopia.

Silicone intubation with tissue glue anastomosis in the treatment of congenital nasolacrimal duct obstruction.

BACKGROUND AND OBJECTIVE: To evaluate the advantages of tissue glue application for the anastomosis of silicone intubation in congenital nasolacrimal duct obstruction. PATIENTS AND METHODS: Patients with congenital nasolacrimal duct obstruction were treated with silicone intubation with the aid of tissue glue for end-to-end anastomosis. The recurrence rate, complications, and the need for general anesthesia at tube removal were recorded. RESULTS: The silicone tubes for all 18 eyes studied were removed smoothly on an outpatient basis. Early extrusion was noted in 3 eyes. No recurrence of epiphora was noted in any eye after more than 6 months of follow-up. CONCLUSION: Tissue glue anastomosis is a beneficial modification that avoids the need for general anesthesia during stent removal in children and allows removal to be easily performed in an outpatient clinic.

Cytomegalovirus retinitis treated with ganciclovir in a renal transplant recipient.

Cytomegalovirus retinitis is an opportunistic and vision-threatening disease in immunosuppressed patients. Currently available antiviral agents have been unsuccessful in halting its progression. We report a case of cytomegalovirus retinitis which occurred 6 months after renal transplantation and was successfully treated with an investigational drug, ganciclovir (DHPG [Dihydroxy propoxymethyl guanine], Cytovene, BW-B759U), via intravenous administration, with resolution of active retinal lesions and the cessation of cytomegalovirus shedding in the urine. There was neither a recurrence of cytomegalovirus retinitis nor an occurrence of retinal detachment during the 9-month follow-up after intravenous ganciclovir therapy.

Dacryocystorhinostomy with intraoperative mitomycin C.

PURPOSE: To observe the effect of intraoperative mitomycin C on the size of the osteotomy site after dacryocystorhinostomy.: METHODS: A total of 15 eyes of 14 patients diagnosed with primary acquired nasolacrimal duct obstruction were assigned randomly to either a mitomycin C group or a control group. The surgical procedures in both groups were exactly the same, except that in the patients in the mitomycin C group, a piece of neurosurgical cottonoid soaked with 0.2 mg/ml mitomycin C was applied to the osteotomy site and then after 30 minutes was removed transnasally. Nasoendoscopic findings were recorded at the completion of the surgery and at 1 month, 3 months, and 6 months after surgery for the two groups. A computer-aided digitizer was used to calculate the surface area of the osteotomy site, and a Student's t test was used to compare the difference between the two groups. RESULTS: All patients in the mitomycin C group remained symptom free after removal of their silicone tube (100% success), and there was one patient in the control group who had recurrent epiphora (87.5% success). Septo-osteotomy adhesion was found in two patients in the control group (25%), but there was no such adhesion found in the patients in the mitomycin C group. In the mitomycin C group, the average final surface area of the osteotomy at the end of the sixth postoperative month was 27.10 +/- 5.78 mm2, whereas that of the control group was only 10.83 +/- 3.37 mm2. Although the immediate postoperative surface area of the osteotomy showed no significant difference between the two groups, a statistically significant difference was noted at 6 months. CONCLUSION: Intraoperative mitomycin C is effective in maintaining a larger osteotomy size. This modification may possibly improve success rates over the traditional dacryocystorhinostomy procedure.

Oncocytic adenomatous hyperplasia of the lacrimal sac: a case report and review of the literature.

Oncocytic tumors of the lacrimal sac are very rare, with only 21 cases documented in the world literature. The authors report a 75-year-old woman who sought treatment for recurrent dacryocystitis and a palpable mass in the left medial canthal area. The patient underwent surgery for removal of a suspected lacrimal sac cancer, but pathologic findings indicated benign oncocytic adenomatous hyperplasia. Complete removal of the tumor and long-term follow-up are necessary in patients with lacrimal sac oncocytic lesions. The authors discuss the characteristic features of ocular adnexal oncocytic lesions and review the literature.

The blood-aqueous barrier in anisometropia and high myopia.

Functional disorder of the blood-ocular barrier has been suggested in cases of degenerative high myopia. Whether the blood-aqueous barrier among young high myopes with healthy vitreous suffers changes is worthy to be explored. Flare density was measured with the laser flare cell meter (Kowa) in highly myopic and anisometropic students. The mean flare density of highly myopic eyes in the myopic group (4.28 +/- 1.13 photon counts/ms) was similar to that of the emmetropic control group (4.24 +/- 1.79 photon counts/ms). Moreover, the difference in flare density between the two eyes of anisometropic patients was not statistically significant. Thus, the blood-aqueous barrier seems intact in young high myopes with healthy posterior vitreous and fundus.

Changes in ocular refraction and its components among medical students--a 5-year longitudinal study.

PURPOSE: Myopic progression has been noted, especially during the period of puberty. It is interesting to investigate whether myopia will progress after the age of puberty and at what rate the changes in ocular components occur during its progression. METHODS: A 5-year longitudinal study was made of refraction and its components among 345 National Taiwan University medical students (690 eyes). The examinations included corneal curvature and cycloplegic refraction measured by auto-refractor and retinoscopy, and axial length measurement with A scan ultrasonography. The same procedures and instruments were used again after 5 years. RESULTS: The myopic prevalence increased from 92.8 to 95.8%; 21 new cases of myopia developed in the 5 years. The mean refractive error significantly increased from -4.26 +/- 2.66 D of freshmen to -4.94 +/- 2.70 D of clerks. The change in refractive error at the 5-year follow-up was 0.70 +/- 0.65 D more myopic for males and 0.54 +/- 0.64 D for females. The main change in the ocular components was in axial length, which increased from 25.54 to 26.05 mm in males and from 24.60 to 24.95 mm in females. Other optical components-including corneal curvature, anterior chamber depth, lens thickness-all remained relatively unchanged from the initial values. CONCLUSIONS: Myopia can progress after the age of puberty, but at a slower rate than during childhood. Axial elongation of the eyeball is the main component that changes in myopic progression.

Experimental myopia in chickens induced by corneal astigmatism.

Astigmatism has been suggested to be an important factor in the production and/or progression of myopia. Chickens have been used as a myopic animal model for several years. In the present investigation our aim was to evaluate the importance of surgically induced corneal astigmatism by peripheral corneal incision with compression suture in one eye, the right, of 3-day-old chicks. Vertical incision (2 mm) with compression suture (nylon 9-0, one stitch) induces against-the-rule astigmatism, horizontal incision with compression induces with-the-rule astigmatism. Four groups were studied 1) with one vertical cut, 2) one horizontal cut, 3) two vertical cuts, 4) two horizontal cuts. The eyes were measured by caliper after 8 weeks. Eye enlargements were induced in all groups, however, less by one cut (astigmatism around 5 diopters) than by two cuts (astigmatism 10 diopters, or more). In the latter groups the pattern of equatorial eye enlargement depended on the axis of the induced astigmatism, the greater elongation being associated with the strongest refracting corneal meridian. All considered, the results suggest that significant corneal astigmatism could be another factor in the production of myopia, possibly acting by way of optical degradation of retinal image quality.