Variation assessment of deformable registration in stereotactic radiosurgery.

INTRODUCTION: The regular functions of CT-MRI registration include delineation of targets and organs-at-risk (OARs) in radiosurgery planning. The question of whether deformable image registration (DIR) could be applied to stereotactic radiosurgery (SRS) in its place remains a subject of debate. METHODS: This study collected data regarding 16 patients who had undergone single-fraction SRS treatment. All lesions were located close to the brainstem. CT and MRI two image sets were registered by both rigid image registration (RIR) and DIR algorithms. The contours of the OARs were drawn individually on the rigid and deformable CT-MRI image sets by qualified radiation oncologists and dosimetrists. The evaluation metrics included volume overlapping (VO), Dice similarity coefficient (DSC), and dose. The modified demons deformable algorithm (VARIAN SmartAdapt) was used for evaluation in this study. RESULTS: The mean range of VO for OARs was 0.84 ± 0.08, and DSC was 0.82 ± 0.07. The maximum average volume difference was at normal brain (17.18 ± 14.48 cm3) and the second highest was at brainstem (2.26 cm3 ± 1.18). Pearson correlation testing showed that all DIRs' OAR volumes were linearly and significantly correlated with RIRs' volume (0.679-0.992, two tailed, P << 0.001). The 100% dose was prescribed at gross tumor volume (GTV). The average maximum percent dose difference was observed in brainstem (26.54% ± 27.027), and the average mean dose difference has found at same organ (1.6% ± 1.66). CONCLUSION: The change in image-registration method definitely produces dose variance, and is significantly more what depending on the target location. The volume size of OARs, however, was not statistical significantly correlated with dose variance.

Prismatic correction of residual esotropia of 20 prism dioptres or less after full hypermetropic correction.

PURPOSE: To assess the efficacy of prismatic correction of residual esotropia

The incidence of asystole in patients undergoing strabismus surgery.

PURPOSE: To investigate the incidence of asystole during strabismus surgery. DESIGN: Retrospective, noncomparative interventional case series. METHODS: Six months to 80 years of age of 3628 consecutive patients who underwent strabismus surgery from October 1994 to May 2007 were enrolled. RESULTS: Four patients (0.11%) under general anaesthesia showed asystole during strabismus surgery. All four were adults of 28, 32, 50, and 53 years of age. Two patients had hypertension and three had preoperative electrocardiographic abnormalities. Three patients had previously undergone uneventful strabismus surgery. CONCLUSIONS: Asystole is likely to be encountered during strabismus surgery with an incidence of ca. 0.11%.

Emergence of diplopia and oscillopsia due to Heimann-Bielschowsky phenomenon after cataract surgery.

The Heimann-Bielschowsky phenomenon (HBP) refers to coarse vertical oscillation of the eye with impaired vision. The ocular movements are strictly monocular, occurring only in the eye with amblyopia. The vertical oscillation is of equal velocity in both vertical directions, or may sometimes be greater in the downward than upward direction. HBP develops several years after loss of vision. It can be differentiated from dissociated nystagmus in spasmus nutans, congenital nystagmus and internuclear ophthalmoplegia based on the strict unilaterality, vertical direction and low frequency. Previously, only a few reports described the development of oscillopsia due to HBP after cataract surgery, which resolved spontaneously or responded to gabapentin. However, visual impairments due to diplopia or oscillopsia from HBP after cataract surgery have received little attention. We report a man who developed persistent vertical diplopia and oscillopsia due to HBP after a cataract operation, which markedly impaired his vision.

Intraoperative extraocular Indocyanine Green (IE-ICG) dye test: a new method of detecting a peeled internal limiting membrane.

AIMS: To develop an intraoperative, extraocular Indocyanine Green dye staining test (IE-ICG) for the differentiation of a peeled ILM from a thin epiretinal membrane, and to evaluate its efficacy. METHODS: This was a consecutive observational case and laboratory observational series. We performed ILM peeling in patients with an idiopathic macular hole (MH, n = 10) and diabetic macular oedema (DME, n = 10) without vital dye staining such as ICG or Trypan Blue. We also performed membrane peeling in patients with an idiopathic epiretinal membrane (ERM, n = 10). Then, the peeled membranes were stained with ICG (1.25 mg/ml) beyond the operation field and examined under a light microscope. After this examination, membranes were fixed with glutaraldehyde, and an electron microscope was used to confirm whether they were ILMs or thin ERM. The concordance rates between surgeon's intraoperative impression of membranes (SI), IE-ICG results (IT) and histological findings (HF) of peeled membranes were evaluated to reveal the efficacy of IE-ICG. RESULTS: The ILMs were homogenously stained with ICG dye (positive IE-ICG), and the ERMs were not stained at all by ICG dye (negative IE-ICG). The concordance rate between IT and HF was 100% in all three groups of patients. However, concordance rates between SI and IT were 100% in MH, 80% in DME and 50% in ERM, respectively. The surgeon's impression of the membrane is inaccurate, especially in patients with idiopathic epiretinal membrane. CONCLUSION: Considering the cost, difficulties of tissue preparation, and the time-consuming process of histological confirmation of an ILM, IE-ICG may be a useful alternative for the differentiation of a peeled ILM and a thin ERM.

Optical coherence tomography in a patient with tobacco-alcohol amblyopia.

AIM: To report optical coherence tomography (OCT) finding in a patient with tobacco-alcohol amblyopia. METHODS: A 45-year-old man presented with a gradual decrease in vision over 4 years. He had smoked a half to one pack of cigarettes per day and had consumed 350 cc of gin per day for 30 years. A detailed ophthalmologic examination was performed. RESULTS: His corrected visual acuities were 20/800 OD and 20/200 OS. A Goldmann visual field examination showed ceco-central scotomas in both eyes. OCT using a peripapillary Fast RNFL (retinal nerve fiber layer) programme showed a small decrease in the RNFL thickness of the superotemporal quadrant in the normative diagram of the right eye in spite of a markedly increased RNFL thickness in both eyes. CONCLUSION: During the phase of visual loss in a patient with tobacco-alcohol amblyopia, visual loss may precede optic disc changes as detected by OCT.

Clinical features and natural history of acquired third, fourth, and sixth cranial nerve palsy.

PURPOSE: Clinical features of acquired third, fourth, and sixth cranial nerve palsy showed variation among previous studies. Evaluation of natural course with objective criteria will establish accurate recovery rates and important factors for recovery. METHODS: Retrospective chart review was performed on 206 patients who visited a neuro-ophthalmic department with acquired third, fourth, and sixth nerve palsy. Aetiology and results of ocular exam on each visit were reviewed, and multivariate logistic regression analysis was performed to identify independent factors affecting recovery. RESULTS: The sixth cranial nerve was affected most frequently (n=108, 52.4%) and vascular disease (n=64, 31.1%) was the most common aetiology. Recovery was evaluated with change of deviation angle for 108 patients, who were first examined within a month of onset and followed up for at least 6 months. Ninety-two (85.2%) patients showed overall (at least partial) recovery and 73 (67.6%) showed complete recovery. In univariate analysis, initial deviation angle was found to be only significant factor associated with complete recovery (P=0.007) and most patients who experienced successful management of treatable underlying disease showed recovery. CONCLUSIONS: With objective criteria based on deviation angle, overall recovery rate from the third, fourth, and sixth nerve palsy was 85.2%. Patients who had smaller initial eyeball deviation or successful management of treatable underlying disease had a high chance of recovery.

Unilateral recession-resection in children with exotropia of the convergence insufficiency type.

PURPOSE: The surgical success rates for intermittent exotropia of the convergence insufficiency type have been reported to be variable, and most were studied retrospectively in adults. The purpose of this study was to evaluate prospectively the long-term surgical results of unilateral lateral rectus (LR) muscle recession and medial rectus (MR) muscle resection in children with intermittent exotropia of the convergence insufficiency type. METHODS: A total of 14 children with intermittent exotropia greater at near than at distance by 10 prism diopters (PD) or more were included in this prospective study. The amounts of resection and recession were based on near and distance deviation, respectively. Minimum follow-up was 1 year (mean 26.6 months; range, 12-68 months) after surgery. The paired t-test was used to compare preoperative and postoperative measurements of the angle of deviation at distance and near, near-distance difference. RESULTS: Significant postoperative reduction was achieved in terms of mean distance exodeviation, from 22.5 PD to 9.1 PD (P=0.000), and mean near exodeviation from 33.8 PD to 13.6 PD (P=0.000). Mean near-distance difference reduced from 11.3 PD preoperatively to 4.6 PD postoperatively (P=0.000). Fresnel prism was used temporarily to treat postoperative esotropia in only one patient for postoperative 6 months. CONCLUSIONS: Unilateral surgery biased to MR strengthening more than LR weakening in children with intermittent exotropia of the convergence insufficiency type, was found to successfully reduce both distance and near deviation and to collapse near-distance differences with a low risk of long-term postoperative esotropia.

Berberine induces apoptosis through a mitochondria/caspases pathway in human hepatoma cells.

Berberine, a main component of Coptidis Rhizoma, is a plant alkaloid with a long history of medicinal use in Chinese medicine. Berberine has indicated significant antimicrobial activity against a variety of organisms including bacteria, viruses, fungi. The mechanism by which berberine initiates apoptosis remains poorly understood. In the present study, we demonstrated that berberine exhibited significant cytotoxicity in hepatoma HepG2 cells but is ineffective in Chang liver cells. Herein we investigated cytotoxicity mechanism of berberine in HepG2 cells. The results showed that HepG2 cells underwent internucleosomal DNA fragmentation after 24-h treatment with berberine (50 microM). Moreover, berberine induced the activation of caspase-8 and -3, and caused the cleavage of poly ADP-ribose polymerase (PARP) and the cytochrome c release, whereas the expression of Bid and anti-apoptosis factor Bcl-XL were decreased markedly. The loss of mitochondrial membrane potential (Delta psim) at 24 h and activation of Fas at 12 h were also seen in the berberine-treated HepG2 cells. These findings supported the fact that the inhibitors of caspases, DEVD-FMK, IETD-FMK and VAD-FMK, prevented apoptosis and restored the expression of Bcl-XL, Bcl-2 and Bid. These results indicated that the potential of anti-hepatoma activity of berberine may be mediated through a caspases-mitochondria-dependent pathway.

The long-term result of slanted medial rectus resection in exotropia of the convergence insufficiency type.

PURPOSE: To evaluate the long-term results of slanted medial rectus (MR) resection for intermittent exotropia (X(T)) of the convergence insufficiency type. METHODS: In all, 10 patients with an X(T) greater at near than at distance by 10 prism diopters (PD) or more were included in this prospective study. Patients received slanted bilateral MR resection. The upper edge of the MR was resected according to the distance exodeviation and the lower edge of the MR was resected according to near exodeviation. The postoperative follow-up period was between 6 and 62 months with a mean of 38.9 months. The paired t-test was used to compare: mean distance angle of deviation preoperatively and postoperatively; mean near angle of deviation preoperatively and postoperatively; and mean near-distance exodeviation difference preoperatively and postoperatively. RESULTS: Bilateral slanted MR resections reduced mean exodeviation at distance from 23.0+/-7.2 to 16.3+/-5.4 PD (P=0.03); mean exodeviation at near from 34.3+/-7.7 to 24.6+/-6.9 PD (P=0.01); and mean near-distance difference from 11.4+/-2.6 to 8.3+/-3.5 PD (P=0.04). At the final follow-up examination, all patients demonstrated an exodeviation of 10 PD or more at distance and near, and the exodeviation difference between distance and near deviation was within 10 PD in five of the 10 patients. Three patients had an esodeviation at distance after surgery, but all resolved within 4 weeks. CONCLUSIONS: Bilateral slanted MR resections in patients with X(T) of the convergence insufficiency type resulted in undercorrection in all patients.

Survival analysis of 365 patients with exotropia after surgery.

PURPOSE: Few reports have included large numbers of exotropia patients. Thus, we undertook this study to perform a survival analysis of over 350 patients with exotropia and to determine which factors might affect the outcome of exotropia surgery. METHODS: The clinical records of 365 patients who underwent exotropia surgery by one surgeon were retrospectively reviewed. Preoperative patient characteristics, surgical procedures performed, and early postoperative ocular alignment were evaluated as potential risk factors of surgical outcome using survival analysis. RESULTS: The estimated median time from surgery to recurrence was 48.3 months. None of the characteristics or procedures were found to be significantly associated with surgical outcome. The likelihood of a good postoperative surgical outcome was highest with an initial postoperative alignment of more than 10 prism diopters of esotropia (P<0.001). CONCLUSIONS: Early postoperative overcorrection was the only predictor of a successful long-term outcome after exotropia surgery.

'Largest angle to target' in surgery for intermittent exotropia.

PURPOSE: To evaluate the safety of the approach based on the notion that the surgical dose for intermittent exotropia should be based on the largest angle ever measured. DESIGN: Prospective case series of 33 patients. METHODS: A total of 33 patients with intermittent exotropia, in whom angles of misalignment at distance or near showed a difference of 15 prism diopters (PD) or more among visits, were included. All the patients were treated by bilateral lateral rectus recession by the same surgeon (JMH), and all were followed up for a minimum of 6 months postoperatively. Short- and long-term surgical results after the initial procedure for intermittent exotropia were analysed. RESULTS: The short-term average result at a postoperative 1 week was 9.3 PD esotropia at distance (range 30 esotropia-16 exotropia). The long-term average results postoperative 6 or 9 months were 4.8 PD exotropia at distance (range 12 esotropia-30 exotropia). At the last follow-up, no overcorrection over 2 PD esophoria at distance was found, and 9 PD of intermittent esotropia and esophoria at near was observed in two patients, respectively. CONCLUSIONS: The strategy of surgical dose for intermittent exotropia based on the largest angle ever measured did not result in overcorrections and is believed to be safe.

Use of polyurethane with sustained release dexamethasone in delayed adjustable strabismus surgery.

AIM: To determine the effect of polyurethane film with sustained release dexamethasone (SRD) in delayed adjustable strabismus surgery. METHODS: A prospective, masked observer, controlled study was performed in rabbits. Thirty four rabbit eyes were divided into three groups. After recession of the superior rectus muscle (SRM), polyurethane film with or without SRD, or balanced salt solution was applied beneath and over SRM in the polyurethane-dexamethasone group (group P-D), polyurethane group (group P), and the control group (group C), respectively. Delayed adjustment was performed once on each SRM at 4 and 6 weeks postoperatively by a masked observer. The possible length to adjust and the necessary force required for the adjustment, as well as the degree of any adhesions, were also evaluated. RESULTS: In the control group, adjustment was impossible in all of the eyes at 4 and 6 weeks postoperatively. In group P-D, adjustment was possible in 11 out of 11 eyes (11/11) 4 weeks postoperatively and in 10/11 eyes 6 weeks postoperatively. In group P, adjustment was possible in 9/11 eyes 4 weeks postoperatively and in 10/12 eyes 6 weeks postoperatively. CONCLUSIONS: Use of polyurethane film with and without SRD could delay adjustment in most eyes for up to 6 weeks postoperatively. Polyurethane is helpful for delaying adjustment in rabbit eyes until 6 weeks postoperatively without the need for frequent topical instillation of steroids.

Efficacy of amblyopia therapy initiated after 9 years of age.

AIMS/PURPOSE: To evaluate the efficacy of occlusion therapy initiated after 9 years of age. METHODS: A total of 16 amblyopes of 9 years or older (range, 9.0-14.5 years; mean, 10.5 years) with a difference in visual acuity of over two lines between the eyes alter 4 weeks of first full-time spectacle wear were included. None of the children had undergone a previous ocular examination, had ever worn spectacles, received occlusion therapy, or had strabismus surgery. Initial worst visual acuity after 4 weeks of full-time spectacle wear was 20/100 in three patients, between 20/80 and 20/40 in 11 patients, and 20/30 in two patients. Full-time occlusion was performed in 14 patients and part-time occlusion in two patients. RESULTS: The final visual acuity of 15 out of 16 patients (94%) improved at least two lines. The final visual acuities ranged from 20/30 to 20/20 in 14 patients, 20/40 in one patient, and 20/50 in one remaining patient who began amblyopia therapy at 14.5 years of age, with the poorest compliance among the patients. CONCLUSIONS: Occlusion therapy for anisometropic and strabismic amblyopia can be successful even if initiated after the age of 9 years.

Stromelysin gene transfer into cultured human trabecular cells and rat trabecular meshwork in vivo.

PURPOSE: To determine whether stromelysin gene can be introduced into and expressed in the cultured human trabecular cells as well as in the rat eye in vivo through means of a recombinant replication-deficient adenovirus. METHODS: Stromelysin cDNA was obtained by reverse transcription-polymerase chain reaction with mRNA extracted from the cultured human trabecular cells after induction with interleukin 1alpha. Adenovirus vector that contains stromelysin cDNA was constructed by cotransfection of pJM17 and pDeltaA.CMV-str into the 293 cells. The expression of stromelysin in the cultured human trabecular cells was assayed by Western blot and zymography. The expression of stromelysin in the trabecular meshwork of the rat eyes was detected by in situ hybridization and immunohistochemistry. RESULTS: The constructed adenovirus vector contained stromelysin cDNA, but no E1 region. Western blot and zymogram revealed that the stromelysin could be expressed and that it possessed enzymatic activity in cultured human trabecular cells. In situ hybridization and immunostaining of the stromelysin showed that the complete form of stromelysin was expressed in the trabecular meshwork, the iris, and the uveoscleral outflow pathway of the rat eye. CONCLUSIONS: Stromelysin, a functional gene, can be transferred in vivo into rat eyes and in vitro into cultured human trabecular cells using a replication-deficient adenovirus vector. This shows the possibility of gene therapy in glaucoma.

Studies on anthracenes. 3. Synthesis, lipid peroxidation and cytotoxic evaluation of 10-substituted 1,5-dichloro-9(10H)-anthracenone derivatives.

The synthesis of a series of 1,5-dichloro-9(10H)-anthracenones bearing O-linked and N-linked substituents in the 10-position are described. Previous studies have shown that 9-acyloxy 1,5-dichloroanthracenes and 9-acyloxy 1,8-dichloroanthracenes displayed a potential cytotoxic effect. These results have encouraged us in further investigation of potential anthracenone derivatives. Therefore, a series of 10-substituted 1,8-dichloro-9(10H)-anthracenone derivatives were synthesized. These compounds were evaluated for their ability to inhibit the growth of human oral epidermoid carcinoma cells (KB cell line), human cervical carcinoma cells of ME 180 (GBM 8401) and Chinese hamster ovary (CHO) cells, respectively. Compounds 3c and 4c of this series compare favorably in the KB cellular assay with mitoxantrone. Compound 4c showed combined inhibitory action against KB, GBM and CHO cell growth, respectively. In addition, redox property of the compounds for the inhibition of lipid peroxidation in model membranes was determined. Compounds 4b and 4d exhibited stronger antioxidant activity than ascorbic acid, (+)-alpha-tocopherol and mitoxantrone, respectively.

Studies on anthracenes. 2. Synthesis and cytotoxic evaluation of 9-acyloxy 1,8-dichloroanthracene derivatives.

The synthesis and cytotoxic evaluation of 9-acyloxy 1,8-dichloroanthracene derivatives are described. The system selectively reduces the carbonyl group flanked by the peri substituents of the anthracenediones to give the corresponding 1,8-dichloro-9(10H)-anthracenone. Simple acylation of anthracenone occurred with appropriate acyl chlorides in CH2Cl2 with a catalytic amount of pyridine to give the 9-acyloxy-1,8-dichloroanthracene derivatives. Considerable interest has developed in the mechanism of how anthracenones achieve this desirable selectivity. These compounds were evaluated in vitro for their ability to inhibit the growth of human oral epidermoid carcinoma cells (KB cell line), human cervical carcinoma cells of ME 180 (GBM 8401) and Chinese hamster ovary (CHO) cells, respectively, as compared to mitoxantrone. The in vitro cytotoxicity evaluation of 9-acyloxy 1,8-dichloroanthracenes against these above cell lines revealed for most of the compounds a cytotoxic potency lower than that of mitoxantrone. The most active compounds were thus selected for further in vitro biological evaluation and structural modification.

Different risks of symptomatic brain necrosis in NPC patients treated with different altered fractionated radiotherapy techniques.

PURPOSE: To report our observation of excessive temporal lobe necrosis in nasopharyngeal carcinoma (NPC) patients treated with 160 cGy b.i.d. radiotherapy technique. During the same period, patients treated with 120 cGy b.i.d. have not shown a similar tendency. Our experience may be useful for designing unconventional radiotherapy regimens for NPC patients. METHODS AND MATERIALS: During the period from October 1991 to January 1998, 81 M0, previously untreated NPC patients completed altered fractionated radiotherapy. Seventy patients were treated with the hyperfractionated technique, and 11 were treated using the accelerated-hyperfractionated scheme. Hyperfractionated radiotherapy was delivered using 120 cGy b.i.d. separated by 6-h intervals throughout the course. A minimum tumor dose of 8000 cGy was the standard dose over an 8-week period. With the accelerated-hyperfractionated scheme, 160 cGy was given twice daily, also with an interval of 6 h. The minimum tumor dose ranged between 6840 and 7640 cGy, with 7 of the 11 patients receiving 7000 cGy. The arrangement of portals was the same for both regimens. The follow-up period for patients alive was from 32 to 102 months with a median of 61 months for the hyperfractionated patients. For the accelerated-hyperfractionated group, it ranged from 67 to 82 months with a median of 72 months. No patient was lost to follow-up. RESULTS: At the time of analysis, 49 of the 70 patients in the hyperfractionated group were alive. In the accelerated group, 8 of the 11 patients were alive. The estimated radiation dose to the temporal lobe for the hyperfractionated group was 6000-7440 cGy with a median of 7080 cGy. For the accelerated-hyperfractionated group, the dose range was 4480-6700 cGy with a median of 6400 cGy. Of the 70 patients treated with hyperfractionated radiotherapy, none developed symptomatic brain necrosis, despite the higher total dose to the temporal lobe in general. In contrast, 3 of the 11 (27%) patients irradiated using the accelerated-hyperfractionated regimen suffered from temporal lobe necrosis at 16, 19, and 40 months after completion of radiotherapy. CONCLUSION: An excessive incidence of temporal lobe necrosis was noted when an accelerated-hyperfractionated regimen with 160 cGy b.i.d. was used in NPC patients with a median brain dose of 6400 cGy. There has been no such event in patients treated using a hyperfractionated regimen with 120 cGy and a median brain dose of 7000 cGy. The real causes of this discrepancy are not known. However, a high sensitivity of the human brain to a change in fraction size may play a role.

Studies on anthracenes. 1. Human telomerase inhibition and lipid peroxidation of 9-acyloxy 1,5-dichloroanthracene derivatives.

The synthetically useful approaches to 9-acyloxy 1,5-dichloroanthracene derivatives are reported. The system selectively reduces the carbonyl group flanked by the peri substituents of the anthracenediones to give the corresponding 1,5-dichloro-9(10H)-anthracenone. Simple regioselective acylation of anthracenone is applied with appropriate acyl chlorides in CH2Cl2 with catalytic amount of pyridine to give the novel 9-acyloxy 1,5-dichloroanthracene derivatives. Considerable interest has developed in the mechanism of how anthracenone achieves this desirable selectivity. In an attempt to understand the mechanism of this reaction, solid-state structures of anthracene derivatives have been obtained. In addition, the inhibition of lipid peroxidation in model membranes was determined as was their ability to inhibit the telomere-addition function of the human telomerase enzyme together with their inhibition of the Taq polymerase enzyme. In contrast to (+)-alpha-tocopherol, 3b, 3c, 3d, 3g, and 3i do not enhance lipid peroxidation in model membranes. Implications for 9-acyloxy 1,5-dichloroanthracene analogues as potential anticancer agents are discussed.

A randomized comparison of prism adaptation and augmented surgery in the surgical management of esotropia associated with hypermetropia: one-year surgical outcomes.

OBJECTIVE: To compare motor and sensory 1-year surgical outcomes in patients with hypermetropic esotropia, managed with either augmented surgery based on the average of the near deviation with and without correction or preoperative prism adaptation. METHODS: Forty-three patients with hypermetropic esotropia without distance-near disparity entered a randomized prospective evaluation of augmented surgery (group A, 27 patients) versus prism adaptation (group P, 16 patients). The formula for augmenting the amount of the rectus muscle recession was based on the average of the near deviation with and without correction in group A and the prism-adapted angle of deviation in group P. During prism adaptation, 9 of 16 patients in group P responded to prism. Motor and sensory outcomes of the Worth 4-dot test at 6 and 0.33 m and the Titmus stereotest were evaluated 1, 3, 6, and 12 months after surgery. RESULTS: Postoperative deviations of 8 PD or less at distance were achieved in 24 of 27 patients (89%) of group A and in 7 of the remaining 8 patients (88%) of prism responders and in all 7 prism nonresponders (100%) in group P. No significant difference existed between groups A and P, as well as between the prism responders and prism nonresponders in group P in terms of near and distance deviation 1 year after surgery. The sensory outcomes improved over time in group A and prism responders. CONCLUSION: There were no significant differences in the surgical outcomes between each group. However, the small sample size may limit the power to detect any statistically significant differences.