Correlation of apparent diffusion coefficient at 3T with prognostic parameters of retinoblastoma.

BACKGROUND AND PURPOSE: Pathologic prognostic parameters for retinoblastoma have been defined. Our purpose was to correlate ADC values at 3T with prognostic parameters of retinoblastoma. MATERIALS AND METHODS: This study included 72 children (30 boys and 42 girls, mean age 19 ± 2.6 months) with retinoblastoma. Pretreatment diffusion-weighted MR imaging was performed on a 3T scanner with b factors of 0, 500, and 1000 seconds/mm(2). ADC values were calculated and pathologic specimens were analyzed. ADC values of the tumors were then correlated with prognostic parameters, including degree of histologic differentiation, tumor size, bilaterality, choroidal invasion, and optic nerve extension. RESULTS: The mean ADC value of retinoblastoma was 0.49 ± 0.12 × 10(-3) mm(2)/s. The ADC values of well- and moderately differentiated tumors were significantly different (P = .007) from poorly and undifferentiated retinoblastoma. There was also a significant difference in the ADC value among small, medium, and large tumors (P = .015), as well as between unilateral and bilateral retinoblastoma (P = .001), and this was independent of the degree of differentiation. The ADC value was also significantly lower (P = .003) when optic nerve invasion was present. There was no correlation of ADC value with growth pattern or choroidal invasion (P = .640 and 0.661, respectively). The ADC value of retinoblastoma was well correlated with the degree of differentiation of the tumor (r = 0.87, P = .007) and inversely correlated with the size of the tumor (r = -0.68, P = .015). CONCLUSIONS: ADC correlated with some of the accepted parameters of poor prognosis for retinoblastoma and may serve as a noninvasive prognostic parameter for assessment of newly diagnosed retinoblastoma.

Correlation between surgical success rate and severity of congenital glaucoma.

AIM: To study the correlation between severity of primary congenital glaucoma (PCG) and success of three types of surgery. METHODS: This was a retrospective review of all records of patients diagnosed with PCG up to age 1 year who underwent goniotomy, trabeculotomy, or combined trabeculotomy-trabeculectomy with mitomycin C as initial procedure between 1982 and 2002 at the King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. 532 paediatric glaucoma patients below age 1 year (820 eyes) with a minimum 1 year follow up were identified. The main outcome measures used for the surgeries were postoperative intraocular pressure, stability of the corneal diameter, and maintenance of corneal clarity. Surgical success was defined as a postoperative intraocular pressure of < or = 21 mm Hg without additional medical or surgical therapy, and with decreased corneal oedema, stabilised corneal diameter, and no additional optic nerve damage for at least 1 year after surgery. Complications, time of surgical failure, and follow up were recorded. RESULTS: The eyes were grouped into mild (249), moderate (342), and severe (229) PCG, based on intraocular pressure, corneal diameter, and clarity. All three surgical procedures resulted in high success rates of 81-100% for the mild form of PCG. Eyes classified with moderate glaucoma had a 13%, 40%, and 80% success rate respectively for goniotomy, trabeculotomy, and combined trabeculotomy-trabeculectomy with mitomycin C. The success rate for severe PCG was 10% and 70% for trabeculotomy and combined surgery respectively. Goniotomy was never done for eyes with this condition. CONCLUSION: Clinical classification of PCG is helpful for surgical decision making. The mild form has a high surgical success regardless of the procedure chosen. Combined trabeculotomy-trabeculectomy with mitomycin C gave the best results for moderate and severe cases of PCG.

Recognized globe perforation during strabismus surgery: incidence, risk factors, and sequelae.

BACKGROUND: Inadvertent perforation of the globe is a well-recognized complication of extraocular muscle surgery. We evaluated the incidence, risk factors, and sequelae of this complication at our institution. METHODS: Medical records of patients who underwent extraocular muscle surgery at King Khaled Eye Specialist Hospital, Saudi Arabia, between September 1983 and April 1997, were reviewed for the occurrence of globe perforation. We documented preoperative visual acuity and refraction, surgical procedure, how the perforation occurred, and immediate management, as well as the sequelae of the perforation, its management, and final outcome. RESULTS: Recognized perforations occurred in 15 of 4886 procedures, for an overall incidence rate of 3/1000. Perforations were 3 times more common in myopic eyes (>-6.00 D, P =.05) and 2 times more common in eyes with previous extraocular muscle surgery. Perforations occurred during muscle reattachment (5 cases), placement of traction sutures at the limbus (4 cases with transient hyphema), muscle disinsertion (3 cases), and placement of sutures at the muscle insertion before disinsertion (3 cases). One patient had a large scleral laceration with uveal prolapse, necessitating scleral patch graft at the time of surgery, and later had retinal detachment surgery with loss of 2 lines of visual acuity. Endophthalmitis, cataract, glaucoma, and phthisis bulbi were not encountered in our review. CONCLUSION: The current incidence of globe perforation is low and only rarely associated with serious sequelae.

Adjuvant chemotherapy with vincristine, doxorubicin, and cyclophosphamide in the treatment of postenucleation high risk retinoblastoma.

PURPOSE: To study risk factors and outcome of children with high risk retinoblastoma who receive postenucleation vincristine, doxorubicin, and cyclophosphamide. PATIENTS AND METHODS: Charts of all patients who received adjuvant chemotherapy for retinoblastoma were reviewed. Thirty-six patients were identified who received chemotherapy for high risk histopathologic features. Histopathology slides of these 36 patients were retrieved and reviewed, and the disease was staged according to the modified St. Jude staging system. The disease was unilateral in 23 patients (64%). There were 9 patients with stage I disease, 18 with stage II, and 9 with stage III. Twenty-four patients (67%) completed 12 of the 12 scheduled chemotherapy cycles, and 11 patients (30%) received 4 to 11 cycles because of relapse, disease progression, or family reasons. A life-threatening complication developed in one patient after the first cycle, and this patient received no further chemotherapy. RESULTS: Five (3 with unilateral and 2 with bilateral disease) of the 36 patients developed distant metastasis and subsequently died. All had massive tumors; three had choroidal and up to surgical margin optic nerve invasion, and two had tumor extending posterior to lamina cribrosa. Six other patients had local relapse or progressive disease. All of these six patients had bilateral disease and failed in the intact eye during (three patients) or after (three patients) chemotherapy. Only two of the six patients were alive with no disease 50 and 102 months from diagnosis. With a median follow-up of 5.6 years, the 5-year and 10-year actuarial overall survival rates were 86% and 74%, respectively. The 5-year survival rates for patients with modified St. Jude stage I, II, and III disease were 100%, 91% (95% confidence interval, 57% to 100%), and 58% (95% confidence interval, 22% to 94%), respectively (P = 0.008). The survival rate was significantly different among patients with optic nerve involvement anterior to lamina cribrosa, posterior to lamina cribrosa, and surgical margin involvement (100%, 55%, and 41%, respectively; P = 0.003). Multivariate analysis showed that only the degree of optic nerve involvement (and therefore, modified St. Jude stage) was predictive of poor outcome. CONCLUSION: Patients with retinoblastoma involving the optic nerve beyond the lamina cribrosa have low survival rate despite local therapy and adjuvant chemotherapy with vincristine, doxorubicin, and cyclophosphamide. Progression of disease in the intact eye of three patients receiving chemotherapy is of concern. Alternative chemotherapeutic agents should be considered for patients with such high risk features.

Combined trabeculotomy and trabeculectomy as an initial procedure in uncomplicated congenital glaucoma.

OBJECTIVE: To review the results of combined trabeculotomy and trabeculectomy as a primary procedure in congenital glaucoma. METHODS: A retrospective review of 100 consecutive eyes in 60 children undergoing surgery from December 30, 1991, to April 17, 1996. Features at initial examination, ie, corneal size and clarity, presence or absence of anterior segment structural abnormalities, and intraocular pressure (IOP), were noted. Data pertaining to perioperative use of mitomycin and the occurrence of complications were collected. After surgery, all patients had IOP, corneal integrity, and any postoperative complication recorded under chloral hydrate sedation. RESULTS: Mean preoperative IOP was 31 mm Hg. Average horizontal corneal diameter was 12.60 mm. Ninety-five eyes had corneal opacification. Twenty-nine eyes had additional anterior segment anomalies, with ectropion uveae (n = 11), Peters anomaly (n = 9), and partial aniridia (n = 7) being the most common. Mitomycin (0.2 or 0.4 mg/mL) was used in 87 eyes. Eleven eyes sustained hyphemas during or just after surgery. Total average follow-up was 304 days. Eyes in which no coexistent anterior segment anomalies were present had a 78% (49 eyes) operative success (IOP, <21 mm Hg); however, in eyes with associated anterior segment anomalies, the success rate was much lower (45% [18 eyes]). The difference in success rates between both groups was statistically significant (P = .03, chi2 test). CONCLUSIONS: Primary combined trabeculotomy and trabeculectomy was a useful initial procedure in uncomplicated congenital glaucoma. This was particularly true where corneal opacification, as in nearly all our eyes, precluded goniotomy, however, where other stigmata of anterior segment dysgenesis coexisted, results were significantly poorer.

Glaucoma in Sturge-Weber syndrome.

BACKGROUND: In glaucoma associated with Sturge-Weber syndrome (SWS), medical treatment often fails to control intraocular pressure, thus requiring surgical intervention that may result in serious complications. METHODS: Eighteen consecutive patients with SWS were reviewed retrospectively at the King Khaled Eye Specialist Hospital. An intraocular pressure less than 20 mm Hg, plus stable optic nerve cup-to-disc ratio and corneal diameter (or visual fields where appropriate), were parameters chosen to indicate that the glaucoma was being controlled. RESULTS: Glaucoma was found in 15 of 18 patients (22 eyes). The mean follow-up time was 62 months (range, 12 to 148 months). Medical treatment alone was successful in 5 patients (7 eyes); the remainder required surgical intervention. The initial surgical procedures included cyclocryotherapy, YAG laser goniotomy, surgical goniotomy, and trabeculotomy or trabeculectomy. Eight eyes required subsequent surgery, 5 with Molteno or Ahmed implants. Early postoperative choroidal effusion and hemorrhage occurred in 4 eyes and resolved spontaneously. Hemorrhagic choroidal detachment with total retinal detachment developed in 2 patients 3 to 5 months after surgery. In 1 patient a recurrent serous choroidal detachment after suture lysis was associated with total optic atrophy. CONCLUSIONS: Glaucoma in SWS is common. Control of glaucoma was successfully achieved with medical treatment in 7 of 22 eyes of our 15 SWS-glaucoma patients, and we consider it the initial treatment of choice. Of the 15 eyes that required surgery, late postoperative complications resulted in loss of vision as a result of persistent postoperative hypotony in 3 eyes that underwent surgical procedures.

Effectiveness and complications of mitomycin C use during pediatric glaucoma surgery.

PURPOSE: To examine the safety of mitomycin C (MMC) use in pediatric glaucoma surgery. DESIGN: Retrospective interventional case series. PARTICIPANTS: One hundred eighty pediatric glaucoma patients younger than 7 years of age (254 eyes) who underwent glaucoma surgery and were followed for at least 1 year participated. INTERVENTIONS: Surgeries consisted of trabeculectomy or combined trabeculotomy-trabeculectomy with adjunctive use of MMC. MAIN OUTCOME MEASURES: Control of intraocular pressure (IOP) and occurrence of complications were measured. An IOP below 21 mmHg without any additional medical or surgical treatment was considered a success. RESULTS: Primary congenital glaucoma was present in 98% of the patients. Sixty percent had a trabeculectomy, and 40% had a trabeculotomy-trabeculectomy. The combined surgery was performed mostly in infants up to 1 year of age. Complications were cystic bleb (19), bleb leak (4), retinal detachment (3), flat anterior chamber (3), cataract (2), and endophthalmitis (1). Children younger than 2 years of age had fewer complications but higher failure rates. The combined procedure in infants up to 2 years of age was moderately more successful (57%) than trabeculectomy alone (39%). Minimal complications seen in this group were more likely related to young age than to the type of surgery. Complications increased with time after surgery, with most occurring 2 years or more after surgery. CONCLUSIONS: Success of MMC-augmented glaucoma filtering surgery increased with age, as did the complication rate. Serious complications were uncommon in the authors' group of pediatric patients up to now. However, complications related to bleb thinning increased with time after surgery, and additional problems can be anticipated with longer follow-up.

Retinoblastoma associated orbital cellulitis.

AIM: Preseptal and orbital cellulitis are rare presenting features of intraocular retinoblastoma. The objectives of this study were to determine the frequency of retinoblastoma associated cellulitis, as well as to review its clinical and histopathological features. METHODS: The medical records of 292 retinoblastoma patients in the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia were reviewed. Those indicating a history of, or presenting with, cellulitis were retrieved and their clinical, radiological, and histopathological variables were assessed. Patients with definite extraocular tumour extension on clinical or radiological examination were excluded. RESULTS: 14 patients were found to have retinoblastoma associated cellulitis (4.8%); nine had bilateral and five had unilateral retinoblastoma. Conjunctival and blood cultures were performed in 10 cases and were negative. 10 children were treated with intravenous steroids, often in conjunction with antibiotics, resulting in a prompt decrease in inflammation. Three other children were treated with antibiotics alone and one received no treatment. Computed tomographic scanning depicted large intraocular tumours occupying between 80% and 100% of the globe in each case. In eight patients, periocular inflammation was radiologically interpreted as possible extraocular extension. In one patient serial computed tomographic scanning showed a reduction in intraocular calcification over time which occurred in the presence of cellulitis, 12 patients underwent enucleation and histopathological examination revealed large necrotic, poorly differentiated tumours associated with uveal involvement and early optic nerve invasion. Focal perilimbal destruction was seen in one patient, and in another peripapillary extrascleral extension was present. 12 patients are alive with a mean follow up of 56.4 months. CONCLUSIONS: Radiological evaluation of scleral integrity may be hindered by periocular inflammatory changes. The orbital cellulitis correlated well with the presence of advanced intraocular retinoblastoma with massive necrosis and anterior chamber involvement. In the majority of patients, cellulitis was not indicative of an extension of retinoblastoma into the orbit. Intravenous steroid treatment reduced orbital inflammation, facilitating examination and subsequent enucleation.

Porous polyethylene orbital implant in patients with retinoblastoma.

OBJECTIVE: The purpose of the study was to assess integration of porous polyethylene allografts in 37 anophthalmic sockets of retinoblastoma enucleations. DESIGN: A clinical review. PARTICIPANTS: Thirty-four patients (19 female, 15 male) whose age when diagnosed with retinoblastoma ranged from 1 to 72 months participated. Sixteen patients had unilateral retinoblastoma and 18 had bilateral retinoblastoma. INTERVENTION: Enucleation (3 bilateral, 31 unilateral) with implantation of a porous polyethylene (PP) sphere (16-20 mm in diameter) was performed. Of the 37 spheres, 34 were primary implants and 3 were secondary implants. In the eight patients with postimplantation exposure, the PP implant had to be removed. MAIN OUTCOME MEASURES: Data on eight sockets with exposed PP implant were measured. RESULTS: There were no implant extrusions, but conjunctival dehiscence-exposure occurred in eight patients (21.6%). In 3 of 37 sockets, the volume replacement was not good, and in 5 cases, fornices were too shallow to accommodate a well-fitting prosthesis. In all but one socket, the overall cosmesis was graded subjectively from acceptable (grade 2) to excellent (grade 3). CONCLUSIONS: Although the PP implant is a useful and a less-expensive alternative to hydroxyapatite in the porous matrix implant category, if conjunctival exposure takes place, the implant presents a serious management problem because of its nonresponsiveness to medical and surgical treatments.

Pediatric intraocular lens implantation. Surgical results and complications in more than 300 patients.

OBJECTIVE: The study aimed to review pediatric intraocular lens (IOL) implantations performed in the authors' institution for the past 7 years. STUDY DESIGN: The study design was a retrospective chart review. PARTICIPANTS: All children who underwent IOL placement between January 1, 1989, and January 31, 1996, at ages 2 to 16 years were studied. Follow-up was a minimum of 6 months up to 4 years with an average of 13 months. INTERVENTION: Placement of a primary or secondary posterior chamber IOL was performed. MAIN OUTCOME MEASURES: Visual acuity and possible complications were tabulated. RESULTS: Fifty-seven percent of the cataracts were caused by trauma, and 37% were infantile cataracts. Visual acuities of 20/40 or better were attained in 44% of eyes and visual acuities of 20/50 to 20/80 were attained in 27% of eyes. Visual acuities were better in children older than 4 years of age (P = 0.001). Compliance with amblyopia therapy improved vision (P = 0.004). Fibrinous membranes occurred in 41 eyes (13%), and posterior capsule opacification occurred in 120 eyes (39%). There were no significant differences in visual outcome and complications between primary and secondary implants (17%) or between capsular bag and sulcus fixation (27%). The first stable postoperative refraction was predicted accurately in most patients, based on the Sanders-Retzlaff-Kraff II (SRK II) formula and intraoperative corneal curvature and axial length determinations. The mean refraction differed from the goal by only +0.28 diopter and 84% were within +/- 2 diopters. A few patients showed large overcorrections or undercorrections. On average, no myopic shift occurred. CONCLUSIONS: Short-term results of IOLs implanted in children older than 2 years of age were favorable. Visual acuities obtained were better than 20/80 in 71% despite a high prevalence (28%) of penetrating trauma. Major complications were rare.

Secondary posterior chamber intraocular lens implantation in children.

BACKGROUND: Primary intraocular lens (IOL) implantation after cataract aspiration is a widely accepted means of correcting pediatric aphakia. However, little is available in the literature on secondary IOL implantation in children. We present our experience over the past 6 years. METHODS: The charts of 57 aphakic children (61 eyes) who underwent secondary posterior chamber IOL implantation between January 1989 and April 1996 were reviewed. In general, these children were either intolerant of or noncompliant with their contact lenses. An attempt was made to correlate visual outcome with patient variables. Evaluation of the ciliary sulcus structure was made in selected patients by ultrasonographic biomicroscopy to reveal any changes resulting from the presence of the IOL haptic in the sulcus. RESULTS: The age range at the time of surgery was 2 to 16 years (mean 8 y). Mean follow-up was 14 months (range 6 to 48 months). Forty-two percent of the patients had a best-corrected visual acuity of 20/40 or better and 78% saw better than 20/80. Posterior capsular opacification occurred in 10 eyes, 8 of which required neodymium:yttrium-aluminum-garnet laser capsulotomy. No major complications occurred. Ciliary sulcus evaluation by biomicroscopy did not reveal any significant ciliary body or scleral erosion. No changes were noted when the implanted sulcus was compared with the normal contralateral side. CONCLUSION: Although follow-up was short, this review suggests that secondary posterior chamber IOL implantation is a safe alternative when other methods of correcting pediatric aphakia fail.

Workup for metastatic retinoblastoma. A review of 261 patients.

PURPOSE: The means available to screen for retinoblastoma metastases, including bone marrow aspiration, lumbar puncture, and radionuclide scans, offer variable usefulness at different stages of the disease. In this study, the authors attempted to assess the value of these tests as part of the initial workup for metastases. METHODS: Medical files of 261 patients with retinoblastoma were reviewed, and the results of bone marrow, lumbar puncture, and bone and liver radionuclide scans were correlated with the laterality, clinical staging, and histopathologic findings. The presence or absence of tumor in the choroid and the optic nerve also were correlated with the results of diagnostic tests. RESULTS: Of 261 patients with retinoblastoma, 147 (56.3%) and 114 (43.7%) had unilateral and bilateral disease, respectively; 11.6% of unilateral cases and 14.9% of bilateral cases had distant metastasis (P = 0.2). Bone marrow aspirations were performed on 101 patients (38.7%), and 10 (9.9%), of these specimens showed the presence of retinoblastoma cells in the aspirate. Ninety-four (36%) of the patients were examined with spinal tap cytology, and the results of four (4.3%) of these were positive for tumor cells. Radionuclide bone and liver scans were performed on 49 (18.8%) and 48 (18.4%) patients, respectively; 5 (10.2%) had abnormal bone scans and 3 (6.2%) had abnormal liver scans. The average age in the metastatic group was 3.1 years, whereas the average age in the nonmetastatic group was 2.3 years. All of our abnormal test results were found in patients with stages III and IV disease, with the exception of one abnormal lumbar puncture in a patient with stage II disease. The correlation of diagnostic tests with the histopathologic findings showed that with no choroidal involvement, no positive diagnostic tests were encountered. Correlation between positive diagnostic test results and the level of optic nerve involvement failed to indicate any trends. CONCLUSION: Our study indicated a good interrelation between the positivity of diagnostic tests (bone marrow and bone scan) and higher stages of the disease (stages III and IV) and choroidal involvement in enucleated eyes, with statistically significant correlations; correlations with lumbar puncture and liver scan were not significant.

Retinal detachment associated with type III retinoblastoma regression after cryotherapy and external-beam radiotherapy.

PURPOSE: To report a child with rhegmatogenous retinal detachment originating from a focus of type III retinoblastoma regression after cryotherapy and external-beam radiation therapy. METHOD: Retinal detachment and multiple retinal holes, which were closely associated with the calcified mass of the regressed retinoblastoma, were treated with cryotherapy and scleral buckle. RESULTS: Positioning the regressed tumor and the retinal holes on the scleral buckle closed the holes. Subretinal fluid gradually reabsorbed after surgery, and complete retinal reattachment resulted. CONCLUSION: Rhegmatogenous retinal detachment is rare in patients with retinoblastoma, and scleral buckle can successfully manage such cases. In our patient, the detachment probably resulted from retinal necrosis secondary to cryotherapy and external-beam radiation therapy.

Presentation of retinoblastoma as phthisis bulbi.

PURPOSE: We sought to determine the incidence of retinoblastoma patients who presented with phthisis bulbi. METHODS: The medical records of 272 patients in the King Khaled Eye Specialist Hospital Retinoblastoma Registry were retrospectively studied. Clinical records, radiological investigations and histopathological slides were reviewed. RESULTS: We found that 2.7% of patients had retinoblastoma coincident with phthisis bulbi. Five of 10 patients had bilateral retinoblastoma; in the others it was unilateral. Radiologically, intraocular calcification was present in all except one case. All enucleated phthisical globes had residual viable tumour cells; optic nerve extension was found in 2 patients who had long-standing phthisis bulbi. CONCLUSION: Phthisis bulbi is an uncommon presenting sign of retinoblastoma which often occurs after an ocular inflammatory episode possibly related to intraocular tumour infarction. In most cases the tumour is not visible because of intraocular disruption. That every enucleated eye in this series harboured well-differentiated tumour cells underlies the seriousness with which phthisis bulbi of unknown origin in children should be investigated for retinoblastoma.

Pediatric IOL implantation: the KKESH experience.

BACKGROUND: Intraocular lens (IOL) implantation is increasingly accepted as a means of correcting pediatric aphakia. However, few large series have been reported. We present our experience over the past 6 years. METHODS: Charts were reviewed of 84 patients (88 eyes) 8 years old or younger who underwent IOL implantation at King Khaled Eye Specialist Hospital between January 1989 and March 1995. An attempt was made to correlate visual outcome with patient variables, and refractive outcome was assessed. RESULTS: Despite a high percentage of patients with penetrating trauma (24%) and a significant level of poor compliance with amblyopia treatment (33%), one third of patients saw 20/40 or better, and 60% had at least 20/80 acuity. Improved visual outcome correlated with later onset and shorter duration of opacity and compliance with occlusion therapy. The posterior capsule was left intact in the majority of cases; opacification occurred in 47 eyes, 25 of which required Nd:YAG capsulotomy. No unexpected complications occurred. Prediction of postoperative pseudophakic refraction was within 2 diopters (D) in 70% of patients. CONCLUSION: IOL implantation in appropriate children can be used as a safe alternative to other methods of correcting pediatric aphakia. Visual outcome often depends on amblyopia management. These patients are appropriately followed by ophthalmologists who are experienced in managing amblyopia and pediatric pseudophakia.

Retinoblastoma referral patterns in Saudi Arabia.

The purpose of this study was to review the patterns of referral and presentation of patients with retinoblastoma in Saudi Arabia from 1983-1994. Retinoblastoma represents a particularly high volume at the King Khaled Eye Specialist Hospital and the Hospital's Retinoblastoma Registry provided relevant data. Records of 257 registered patients were analyzed. Of these, 112 were bilateral whereas 145 were unilateral, resulting in a total of 369 eyes. Referral diagnosis accuracy was high, 75% of referring physicians ranking retinoblastoma at the top of their differential diagnosis. Delay in referral was found to average 9.4 weeks. However, 49.4% of eyes were staged at Reese-Ellsworth Stage V at presentation. Significantly, the number of patients presenting with extraocular disease fell from 22.8% (1983-1988) to 12.3% (1989-1994), highlighting increasing awareness of retinoblastoma and availability of services in Saudi Arabia.