Evaluation of Urinary Tract Dilation Classification System for Prediction of Long-Term Outcomes in Isolated Antenatal Hydronephrosis: A Cohort Study.

PURPOSE: The aim of this study was to evaluate the performance of the new classification of urinary tract dilatation (UTD) to predict long-term clinical outcomes in infants with isolated antenatal hydronephrosis (ANH). MATERIALS AND METHODS: Between 1989 and 2019, 447 infants diagnosed with isolated severe ANH and were prospectively followed. The main predictive variable for the analysis was the new UTD classification system. The events of interest were surgical interventions, urinary tract infections, chronic kidney disease stage II or higher, hypertension and proteinuria. The primary end-point was time until the occurrence of a composite event of renal injury, including proteinuria, hypertension and chronic kidney disease. RESULTS: Among 447 infants with ANH included in the analysis, 255 (57%) had UTD P1, 93 (20.8%) UTD P2 and 99 (22.2%) UTD P3. Median followup time was 9 years (IQR 7-12 years). Of 447 patients included in the analysis, 11 (2.5%) had hypertension, 13 (2.9%) exhibited persistent mild proteinuria, 14 (3%) developed chronic kidney disease Stage 2 and 26 (5.8%) had the composite outcome of renal injury. By survival analysis, the UTD system predicted accurately all events of interest. According to the Kaplan-Meier survival analysis, the probability of renal injury at 20 years of age was estimated at about 0%, 14% and 56% for patients assigned to UTD P1, UTD P2 and UTD P3, respectively (p <0.001). CONCLUSIONS: Our findings provide insights that the new UTD classification has a good performance for discriminating not only mid-term, but also long-term clinical outcomes, including renal injury.

Clinical outcome is associated with the Urinary Tract Dilatation Classification System grade.

AIM: To assess the association between the Urinary Tract Dilatation (UTD) Antenatal (A) and Postnatal (P) Classification System grade and the outcome in term newborns. METHODS: This retrospective study enrolled 166 term newborns (71% boys, 206 ureterorenal units) evaluated for unilateral or bilateral UTD in the Neonatology Department of Ljubljana University Medical Center from 2012 to 2018. Data on family history, sex, gestational age, birth weight, head circumference, Apgar score, possible oligohydramnios, indication for and age at first postnatal ultrasound, time of follow-up, and clinical outcome were collected. Radiology records were reviewed to grade UTD according to the Multidisciplinary Consensus on the Classification of Prenatal and Postnatal UTD. RESULTS: The majority of ureterorenal units with UTD A 2-3 had UTD P 2 or 3. Spontaneous resolution, specific uropathy, the need for surgery, and the risk of urinary tract infection were all significantly associated with the UTD P grade. No patient experienced renal dysfunction at the end of follow-up (12-48 months, median 24 months), and therefore this parameter was not associated with the UTD P grade. CONCLUSIONS: The UTD grade was associated with the probability of spontaneous resolution, time to its occurrence, specific uropathies urinary tract infection, and risk for surgery. However, no association with renal dysfunction was established.

Prenatal and postnatal urinary tract dilation: advantages of a standardized ultrasound definition and classification.

Urinary tract dilatation is identified sonographically in 1-2% of fetuses and reflects a spectrum of possible nephro-uropathies. There is significant variability in the clinical management of individuals with prenatal urinary tract dilatation to postnatal urinary pathologies, because of a lack of consensus and uniformity in defining and classifying urinary tract dilation. Ultrasonography is the first step to screen and diagnose kidneys and the urinary tract diseases of the children. The need for a correct ultrasound approach led to the realization of algorithms aimed at standardizing the procedures, the parameters and the classifications. Our objective was to highlight the strengths of the Classification of Urinary Tract Dilation (UTD) suggested by the Consensus Conference which took place in 2014 with the participation of eight Scientific Societies and was subsequently published on the Journal of Pediatric Urology. Before its spread out, the definition of UTD was not uniform and the ultrasonographic measurements were not clearly defined, leading to misunderstandings between physicians. The Classification by the Consensus Conference of 2014 represents a revolutionary tool for the diagnosis and management of UTD. Furthermore, the parameters suggested by the classification proposed are applicable for both prenatal and postnatal classification, ensuring a correct follow-up in children with UTD whose diagnosis had been already made during pregnancy.

Society for Fetal Urology Classification vs Urinary Tract Dilation Grading System for Prognostication in Prenatal Hydronephrosis: A Time to Resolution Analysis.

PURPOSE: The Urinary Tract Dilation grading system for prenatal hydronephrosis was introduced to address potential shortcomings of the Society for Fetal Urology classification. Hydronephrosis resolution is an important patient outcome and is frequently discussed during family counseling. We compared these 2 grading systems and their ability to predict time to hydronephrosis resolution. MATERIALS AND METHODS: We prospectively screened 855 patients with prenatal hydronephrosis due to ureteropelvic junction obstruction-like hydronephrosis, nonrefluxing primary megaureter or vesicoureteral reflux between 2009 and 2015. Of the patients 454 were excluded due to surgery, late referral, absence of postnatal dilatation or presence of other anomalies, resulting in 401 eligible patients (of whom 81% were male) to be included for analyses. Hydronephrosis grades collected at baseline and last followup were compared to identify resolution trends through time. Hydronephrosis resolution was defined as renal pelvis anteroposterior diameter 10 mm or less at last followup. Time to resolution was analyzed using Cox proportion regression. RESULTS: Of 401 patients 328 (82%) had resolution during a mean ± SD followup of 24 ± 18 months (maximum 107). Cumulative resolution rate at 3 years was 98% for Society for Fetal Urology grade I hydronephrosis, 87% for grade II, 76% for grade III and 57% for grade IV. The 3-year hydronephrosis resolution rate was 90% for Urinary Tract Dilation postnatal grade 1 (low risk), 81% for grade 2 (intermediate risk) and 71% for grade 3 (high risk). CONCLUSIONS: Patients with distinctive baseline hydronephrosis grades (classified by Society for Fetal Urology or Urinary Tract Dilation system) had significantly different resolution times for hydronephrosis (p <0.001). Counseling families regarding time to resolution of prenatal hydronephrosis should remain the same whether using Society for Fetal Urology or Urinary Tract Dilation grading system.

Classification of pediatric urinary tract dilation: the new language.

The multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system) was created to unify the language used to describe urinary tract dilation on antenatal and postnatal ultrasound examinations and thereby facilitate communication among providers and improve outcomes research. The background and new classification system are described in this review, with imaging examples.

Conversion and reliability of two urological grading systems in infants: the Society for Fetal Urology and the urinary tract dilatation classifications system.

BACKGROUND: The urinary tract dilation (UTD) classification system was proposed in 2014. OBJECTIVE: To evaluate the correspondence and reliability of two US grading systems for postnatal urinary tract dilatation in infants: the Society for Fetal Urology (SFU) and the UTD systems. MATERIALS AND METHODS: We assessed 180 kidneys in infants younger than 1 year. Four radiologists assessed the kidneys twice using both the SFU system (grades 0 to 4) and the UTD system (grades normal, P1, P2, P3). The SFU system was re-categorized into SFU-A (grades 0, 1-2, 3, 4) and into SFU-B (grades 0-1, 2, 3, 4). The Cohen kappa statistic was used for estimating agreement of both UTD-SFU-A and UTD-SFU-B. RESULTS: The Cohen kappa was significantly higher between UTD and SFU-B as compared to the UTD and SFU-A (0.75 vs. 0.50, P < 0.001). Intra-observer agreement was similar for the two grading systems (SFU 0.64-0.88 vs. UTD 0.48-0.92, P = 0.050-0.885). SFU grades 2 and 3 showed fair to moderate inter-observer agreement and corresponding UTD grades P1 and P2 showed moderate to substantial agreement. The overall inter-observer agreement was significantly higher for the UTD system than for the SFU system during the first assessment (95% confidence interval [CI]: right kidney, -0.069 to -0.062; left kidney, -0.048 to -0.043). CONCLUSION: Correspondence between the systems was poor using a recommended re-categorization (SFU-A). An alternative re-categorization (SFU-B) was found to be more appropriate for establishing correspondence between the systems. Both systems were reliable, with good intra- and inter-observer agreement for the assessment of infant kidneys, but the UTD system had better inter-observer agreement.

[Evaluation of a Classification Model of Horizontal Vascular Lesions of the Vocal Folds]. / Evaluation eines Klassifikationsmodells horizontaler Gefäßveränderungen der Stimmlippen.

OBJECTIVE: There exists no valid classification of beginning vascular changes of the vocal folds. We tested an own classification model of visible beginning horizontal vascular changes. MATERIAL AND METHODS: 168 indirect endoscopic pictures (84 white light=WL and 84 Narrow Band Imaging=NBI) of vocal folds were presented to 3 different consultants for classification (graduation normal, slight, moderately, high-grade belonged to the vascular features ectasia, meander, convolute, frequency of the vessels, ramification, change in direction). The self-confidence was declared by the consultants with a numeric rating scale. RESULTS: A classification of beginning vascular changes of the vocal folds is possible, especially of ectasia, meander, convolute, frequency of the vessels, ramification, change in direction (p<0.0001). Significantly more vascular lesions can be detected by NBI than with white light endoscopy alone (p<0.0001). There are no significant differences (p=0.3529) in self-confidence of the classification. But it differs between the consultants highly significant (p<0.0001). The inexperienced classifier shows the highest growth in the learning curve. The intrarater- and interrater-variability differs only slightly between WL and NBI. CONCLUSIONS: Beginning horizontal changes of vocal fold vessels can be classified. Endoscopic NBI-pictures of the vocal folds demonstrate the beginning of vascular changes better compared to endoscopic white light pictures alone. The familiarity and expertise with the classification model and the endoscopic imaging technique affect the self-confidence of the evaluation.

Multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system).

OBJECTIVE: Urinary tract (UT) dilation is sonographically identified in 1-2% of fetuses and reflects a spectrum of possible uropathies. There is significant variability in the clinical management of individuals with prenatal UT dilation that stems from a paucity of evidence-based information correlating the severity of prenatal UT dilation to postnatal urological pathologies. The lack of correlation between prenatal and postnatal US findings and final urologic diagnosis has been problematic, in large measure because of a lack of consensus and uniformity in defining and classifying UT dilation. Consequently, there is a need for a unified classification system with an accepted standard terminology for the diagnosis and management of prenatal and postnatal UT dilation. METHODS: A consensus meeting was convened on March 14-15, 2014, in Linthicum, Maryland, USA to propose: 1) a unified description of UT dilation that could be applied both prenatally and postnatally; and 2) a standardized scheme for the perinatal evaluation of these patients based on sonographic criteria (i.e. the classification system). The participating societies included American College of Radiology, the American Institute of Ultrasound in Medicine, the American Society of Pediatric Nephrology, the Society for Fetal Urology, the Society for Maternal-Fetal Medicine, the Society for Pediatric Urology, the Society for Pediatric Radiology and the Society of Radiologists in Ultrasounds. RESULTS: The recommendations proposed in this consensus statement are based on a detailed analysis of the current literature and expert opinion representing common clinical practice. The proposed UTD Classification System (and hence the severity of the UT dilation) is based on six categories in US findings: 1) anterior-posterior renal pelvic diameter (APRPD); 2) calyceal dilation; 3) renal parenchymal thickness; 4) renal parenchymal appearance; 5) bladder abnormalities; and 6) ureteral abnormalities. The classification system is stratified based on gestational age and whether the UT dilation is detected prenatally or postnatally. The panel also proposed a follow-up scheme based on the UTD classification. CONCLUSION: The proposed grading classification system will require extensive evaluation to assess its utility in predicting clinical outcomes. Currently, the grading system is correlated with the risk of postnatal uropathies. Future research will help to further refine the classification system to one that correlates with other clinical outcomes such as the need for surgical intervention or renal function.

Coronary collateral circulation in patients of coronary ectasia with significant coronary artery disease.

OBJECTIVES: Patients with coronary ectasia (CE) usually have coexisting coronary stenosis resulting in myoischemia. Coronary collateral plays an important role in protecting myocardium from ischemia and reducing cardiovascular events. However, limited studies investigate the role of CE in coronary collaterals development. METHODS: We evaluated 1020 consecutive patients undergoing coronary angiography and 552 patients with significant coronary artery disease (SCAD), defined as diameter stenosis more than 70%, were finally analyzed. CE is defined as the ectatic diameter 1.5 times larger than adjacent reference segment. Rentrop collateral score was used to classify patients into poor (grades 0 and 1) or good (grades 2 and 3) collateral group. RESULTS: 73 patients (13.2%) had CE lesions which were most located in the right coronary artery (53.4%). Patients with CE had a lower incidence of diabetes (43.8% vs 30.1%, p = 0.03), higher body mass index (25.4±3.5 vs 26.7±4.6, p = 0.027) and poorer coronary collateral (58.2% vs 71.2%, p = 0.040). Patients with poor collateral (n = 331) had a higher incidence of CE (15.7% vs 9.5%, p = 0.040) and fewer diseased vessels numbers (1.96±0.84 vs 2.48±0.69, p<0.001). Multivariate analysis showed diabetes (odd ratio (OR) 0.630, p = 0.026), CE (OR = 0.544, p = 0.048), and number of diseased vessels (OR = 2.488, p<0.001) were significant predictors of coronary collaterals development. CONCLUSION: The presence of CE was associated with poorer coronary collateral development in patients with SCAD.

Clinical grading of post-LASIK ectasia related to visual limitation and predictive factors for vision loss.

PURPOSE: To evaluate and characterize the main clinical features of post-laser in situ keratomileusis (LASIK) ectasia, propose a grading system based on visual limitation, and identify predictive factors related to the degree of visual loss. SETTING: Vissum Corp., Alicante, Spain. DESIGN: Retrospective case series. METHODS: This study comprised consecutive eyes with corneal ectasia after LASIK from 1996 to 2010. Main outcomes were post-LASIK ectasia corrected distance visual acuity (CDVA), CDVA loss, spherical equivalent (SE), and the corneal bulge (delta K). These outcomes were correlated with the residual stromal bed, ablation depth, ablation ratio (ablation depth:pachymetry), corneal depth (flap + ablation depth), and corneal ratio (corneal depth:pachymetry) to characterize their role in the severity of the disease. RESULTS: The mean post-LASIK ectasia CDVA, CDVA loss, SE, and delta K were 0.20 logMAR ± 0.18 (SD), -0.13 ± 0.15 logMAR, -3.80 ± 3.86 diopters (D), and 4.77 ± 4.23 D, respectively. The ablation ratio had the strongest correlation with post-LASIK ectasia CDVA (ρ = 0.477 and P<.001), whereas the corneal ratio had the strongest correlation with the post-LASIK ectasia SE and delta K (ρ = -0.614 and ρ = 0.453, respectively: P<.001). The ablation ratio was the main predictive factor for post-LASIK ectasia CDVA loss (relative risk, 2.04; P=.049). CONCLUSIONS: The grading system based on visual limitation was consistently represented by differences in CDVA loss, SE, and delta K. A high amount of tissue removed by the refractive procedure was associated with greater corneal biomechanical destabilization, increased corneal steepening, and a worse prognosis.

An observational study into the management of arteriomegaly: a call for a revised classification system.

INTRODUCTION: Arteriomegaly is the diffuse ectasia of arteries with or without aneurysmal disease. Patients with arteriomegaly have a higher incidence of morbidity including limb loss compared to patients with other arteriopathies. The aim of this observational study was to review the management of these patients in our institution. METHODS: Radiologists and surgeons prospectively reviewed aortofemoral angiography. Patients with arteriomegaly were identified. Data relating to demographics, mode of presentation, risk factors, type of arteriomegaly, management and progression of disease were analysed. RESULTS: Arteriomegaly was identified in 1.3% of patients (n = 69) undergoing lower limb angiography in the study period. Of these, the majority (n = 67) were men. The mean age was 74 years (range: 60-89 years) and 76% were smokers. Co-morbidities included coronary artery disease (55%), diabetes mellitus (20%), hypertension (45%) and cerebrovascular events (6%). Forty-nine patients presented with critical limb ischaemia and eighteen patients were seen electively in the outpatients department with symptoms of intermittent claudication. Data were incomplete for two male patients and were therefore not included. At presentation, 22 patients were classified as Hollier type I, 5 were type II and 9 were type III. Thirty-one patients had arteriomegalic vessels but no aneurysmal disease. After a median follow-up duration of 76 months (range: 6-146 months), 34 patients progressed to type I, 2 to type II and 18 to type III. Thirteen remained without aneurysmal disease. Twenty-nine patients required angioplasty and twenty-eight required bypass surgery during this time. In total, 102 procedures were required for complicated disease. The limb salvage rate was 92%. Although 8 patients in our series died, the remaining 59 are under regular follow up. CONCLUSIONS: This study illustrates the progressive nature of arteriomegaly. Results of the management of these patients in our institution are similar to those in the literature. We suggest an additional fourth category to Hollier's classification that describes arteriomegalic disease without aneurysmal degeneration as this, too, deserves special management. Regular follow-up visits and early intervention for patients with arteriomegaly is advocated to reduce the high incidence of morbidity.

The prevalence and clinical profile of angiographic coronary ectasia.

OBJECTIVE: To determine the incidence of Coronary Artery Ectasia (CAE) at our teaching hospital to describe the patients and angiographic characteristics. METHODS: A retrospective analysis was conducted on all coronary angiograms performed at the catheterization laboratory of Karachi Institute of Heart Diseases, a tertiary care center, between the period of August 2006 and August 2008. A one year follow up was performed to look for primary and secondary endpoints. Data were collected from catheterization films, and medical records. RESULTS: Five thousand coronary angiograms were performed during the periof of the study. A total of 140 (2.8%) angiograms showed coronary ectasia of both mixed and pure types. Pure ectasia with no coronary obstructive lesions was seen in 75 (1.5%). The left anterior descending artery (LAD) was the most commonly affected vessel (63%) followed by the right coronary artery (RCA) 25% and 10% patients had circumflex artery involvement. The primary composite endpoint showed 6 (4.2%) patients with non-ST elevation MI, 5 (3.6%) with ST elevation inferior wall myocardial infarction, 70 (50%) with unstable angina and 2 (1.4%) deaths due to pulmonary oedema. Secondary endpoints showed 50% of the patients still complaining of chest pain. CONCLUSION: Prevalence of Coronary ectasia in the population presenting to KIHD during the study period was 1.5%. Majority of patients were males, associated with dyslipidaemia, hypertension and smoking. CAE was associated with obstructive coronary artery disease in about 80% of cases. LAD was the most commonly affected vessel.

Current diagnosis and management of syringocele: a review.

Cowper's syringocele is a rare but an under-diagnosed cystic dilation of the Cowper's ducts and is increasingly being recognized in the adult population. Recent literature suggests that syringoceles be classified based on the configuration of the duct's orifice to the urethra, either open or closed, as this also allows the clinical presentations of 2 syringoceles to be divided, albeit with some overlap. Usually post-void dribbling, hematuria, or urethral discharge indicates open syringocele, while obstructive symptoms are associated with closed syringoceles. As these symptoms are shared by many serious conditions, a working differential diagnosis is critical. Ultrasonography coupled with retro and ante grade urethrography usually suffices to diagnose syringocele, but supplementary procedures - such as cystourethroscopy, computed tomography scan, and magnetic resonance imaging - can prove useful. Conservative observation is first recommended, but persistent symptoms are usually treated with endoscopic marsupialization unless contraindicated. Upon reviewing the literature, this paper addresses the clinical anatomy, classification, presentation, diagnosis, and treatment of syringoceles in further detail.

Current diagnosis and management of syringocele: a review

Cowper's syringocele is a rare but an under-diagnosed cystic dilation of the Cowper's ducts and is increasingly being recognized in the adult population. Recent literature suggests that syringoceles be classified based on the configuration of the duct's orifice to the urethra, either open or closed, as this also allows the clinical presentations of 2 syringoceles to be divided, albeit with some overlap. Usually post-void dribbling, hematuria, or urethral discharge indicate open syringocele, while obstructive symptoms are associated with closed syringoceles. As these symptoms are shared by many serious conditions, a working differential diagnosis is critical. Ultrasonography coupled with retro and ante grade urethrography usually suffices to diagnose syringocele, but supplementary procedures - such as cystourethroscopy, computed tomography scan, and magnetic resonance imaging - can prove useful. Conservative observation is first recommended, but persistent symptoms are usually treated with endoscopic marsupialization unless contraindicated. Upon reviewing the literature, this paper addresses the clinical anatomy, classification, presentation, diagnosis, and treatment of syringoceles in further detail.

[Salivary stones and stenosis. A comprehensive classification]. / Lithiases et sténoses salivaires. Une classification pratique des pathologies non tumorales.

INTRODUCTION: Sialendoscopy and sialo-MRI enable diagnosis of salivary gland obstructive pathologies, such as lithiasis, stenosis and dilatations. Therefore, a classification of these pathologies is needed, allowing large series comparisons, for better diagnosis and treatment of salivary pathologies. MATERIAL AND METHODS: With help from people from the European Sialendoscopy Training Center (ESTC), the results of sialographies, sialoMRI and sialendoscopies, a comprehensive classification of obstructive salivary pathologies is described, based on the absence or presence of lithiasis (L), stenosis (S) and dilatation (D) ("LSD" classification). DISCUSSION: It appears that a classification of salivary gland obstructive pathologies should be described. We hope it will be widely used and of course criticized to be improved and to compare the results of salivary gland diagnostic methods, such as sialography and sialendoscopy and also the results and indications for salivary gland therapeutic methods, such as lithotripsy, sialendoscopy and/or open surgery.

Salivary stones and stenosis. A comprehensive classification.

INTRODUCTION: Sialendoscopy and sialoMRI enables diagnosis of salivary gland obstructive pathologies, such as lithiasis, stenosis, and dilatations. Therefore, a classification of these pathologies is needed, allowing large series comparisons, for better diagnosis and treatment of salivary pathologies. MATERIAL AND METHODS: With help from people from the European Sialendoscopy Training Center (ESTC), the results of sialographies, sialoMRI and sialendoscopies, a comprehensive classification of obstructive salivary pathologies is described, based on the absence or presence of lithiasis (L), stenosis (S), and dilatation (D) ("LSD" classification). DISCUSSION: It appears that a classification of salivary gland obstructive pathologies should be described. We hope it will be widely used and of course criticized to be improved and to compare the results of salivary gland diagnostic methods, such as sialography and sialendoscopy, and also the results and indications for salivary gland therapeutic methods, such as lithotripsy, sialendoscopy, and/or open surgery.

How many patients would be misclassified using M-mode and two-dimensional estimates of left atrial size instead of left atrial volume? A three-dimensional echocardiographic study.

OBJECTIVES: Left atrial size has shown prognostic importance in a variety of cardiac conditions. Diameters, area, and volume derived from M-mode and two-dimensional (2D) echocardiography are commonly used to estimate left atrial size. However, M-mode and 2D measures of left atrial size rely on various geometrical assumptions and their accuracy remains to be determined. To address this issue, we compared M-mode and 2D parameters routinely used to estimate left atrial size with three-dimensional (3D) echo measured left atrial volume (LAV) as a reference standard. METHODS: We studied 104 patients (55% males, 62 +/- 15 years, range 10-87 years), presenting for a routine echocardiographic evaluation. RESULTS: The mean 3D LAV for the study population was 90 +/- 68 ml (range 24-458 ml). We found highly significant (P < 0.0001) correlations between 3D LAV and left atrial anterior-posterior (r = 0.78, 95% CI = 0.69-0.85), superior-inferior (r = 0.74, 95% CI = 0.63-0.81) and medial-lateral (r = 0.91, 95% CI = 0.86-0.93) diameters. A highly significant correlation was also found between 3D LAV and left atrial area (r = 0.94, 95% CI = 0.91-0.96). However, using M-mode anterior-posterior diameter or left atrial area would have misclassified 57% and 70% of our study patients, respectively, regarding the degree of left atrial dilatation. Closer correlations and narrower confidence intervals were found between 3D LAV and single-plane (r = 0.98; 95% CI = 0.94-0.97) and biplane (r = 0.97; 95% CI = 0.96-0.98) 2D LAVs. CONCLUSION: Left atrial diameters and area measurements were poor predictors of 3D LAV, especially in the enlarged left atria. Therefore, these parameters can be misleading in assessing the severity of left atrial dilatation. Two-dimensional LAVs are accurate in estimating 3D LAV. The small additional accuracy obtained by using the biplane instead of the single-plane area-length method, and the fact that the biplane method is more technically demanding and time consuming, may allow the use of the area-length for routine clinical use.

Risk factors for corneal ectasia after LASIK.

PURPOSE: To establish a grading system that helps identify high-risk individuals who may experience corneal ectasia after LASIK. DESIGN: Retrospective, comparative, interventional case series. PARTICIPANTS: One hundred forty-eight consecutive patients (148 eyes) were included in this study. Thirty-seven patients who underwent LASIK at other refractive centers experienced corneal ectasia in 1 eye after LASIK. One hundred eleven eyes of 111 patients who underwent successful LASIK during the same period were age and gender matched and served as controls. INTERVENTION: All patients underwent preoperative and postoperative topographic analysis of the cornea. The follow-up period in both groups of patients ranged from 2 to 5 years, with a mean follow-up of 3.6 years. All patients underwent LASIK for myopia (spherical equivalent, -4.00 to -8.00 diopters). MAIN OUTCOME MEASURES: Corneal keratometry, oblique cylinder, pachymetry, posterior surface elevation, difference between the inferior and superior corneal diopteric power, and posterior best sphere fit (BSF) over anterior BSF were given a grade of 1 to 3 each. An ectasia grading system was established, and the cumulative risk score was assessed. RESULTS: Patients who had a grade of 7 or less showed no evidence of corneal ectasia, whereas 16 (59%) of 27 patients who had a grade of 8 to 12 had corneal ectasia. Twenty-one (100%) of 21 patients with a grade of more than 12 had corneal ectasia after LASIK (P<0.0001). CONCLUSIONS: A risk score may help in the prediction of patients who are at risk of experiencing corneal ectasia after LASIK. A prospective clinical study is needed to assess the validity of these risk factors.