Oncological outcome after MRI-based selection for neoadjuvant chemoradiotherapy in the OCUM Rectal Cancer Trial

BACKGROUND

It is not clear whether all patients with rectal cancer need chemoradiotherapy. A restrictive use of neoadjuvant chemoradiotherapy (nCRT) based on MRI findings for rectal cancer was investigated in this study.

METHODS

This prospective multicentre observational study included patients with stage cT2-4 rectal cancer, with any cN and cM0 status. Carcinomas in the middle and lower third that were 1 mm or less from the mesorectal fascia, all cT4 tumours, and all cT3 tumours of the lower third were classified as high risk, and these patients received nCRT followed by total mesorectal excision (TME). All other carcinomas with a minimum distance of more than 1 mm from the mesorectal fascia and those in the upper third were classified as low risk; these patients underwent TME alone (no nCRT). Patients were followed for at least 3 years. Outcomes were the rates of local recurrence, distant metastasis and survival.

RESULTS

Among 545 patients included, 428 were treated according to the study protocol: 254 (59·3 per cent) had TME alone and 174 (40·7 per cent) received nCRT and TME. Median follow-up was 60 months. The 3- and 5-year local recurrence rates were 1·3 and 2·7 per cent respectively, with no differences between the two treatment protocols. Patients with disease requiring nCRT had higher 3- and 5-year rates of distant metastasis (17·3 and 24·9 per cent respectively versus 8·9 and 14·4 per cent in patients who had TME alone; P = 0·005) and worse disease-free survival compared with that in patients who did not need nCRT (3- and 5-year rates 76·7 and 66·7 per cent, versus 84·9 and 76·0 per cent in the TME-alone group; P = 0·016).

CONCLUSION

Restriction of nCRT to high-risk patients achieved good results.

Cognitive Deficits in Chronic Stroke Patients: Neuropsychological Assessment, Depression, and Self-Reports

BACKGROUND

Following stroke, clinicians are challenged to detect and untangle symptoms of cognitive dysfunction and mood disorders. Additionally, they need to evaluate the informative value of self-reports to identify patients in need of further attendance.

AIMS

To examine the association between neuropsychological measures, symptoms of depression, and self-reported cognitive function.

METHODS

One-hundred and five chronic stroke patients underwent assessment covering 6 cognitive domains and answered the Hospital Anxiety and Depression Scale and the Memory and Thinking Scale from the Stroke Impact Scale 1 year after stroke. Age and gender difference in cognitive impairment were examined; linear regression was used to predict depression scores. Sensitivity and specificity analyses were used to validate self-reported functioning against performance on cognitive tests.

RESULTS

Cognitive impairment was observed in 60% of the patients in at least 1 cognitive domain. Cognitive performance was associated with symptoms of depression as well as with self-reported cognitive function. The final analyses revealed low sensitivity and specificity for the Memory and Thinking subscale from the Stroke Impact Scale.

CONCLUSION

Cognitive impairment occurs frequently even in patients in a chronic phase after stroke and predicts symptoms of depression. Using the Stroke Impact Scale, clinicians should be aware of low sensitivity of self-reported cognitive function.

Olfactory dysfunction in chronic stroke patients

Background

The aim of the study was to investigate odor identification performance in patients one year after hospital admittance due to stroke. Predictors for olfactory dysfunction were investigated as well as self-reported olfactory function and pleasantness of olfactory items.

Methods

A 1-year prospective study was performed. Stroke location, classification and comorbidities were registered at hospital admission. One year after admission, olfactory function was assessed using standardized olfactory methods (screening for loss of detection sensitivity and an odor identification test). A group of matched controls was derived from a population-based study to compare odor identification performance between groups. Patients were asked for their personal judgment regarding their olfactory function and pleasantness of odorous items. In addition, global cognitive function and symptoms of depression were assessed.

Results

A total of 78 patients were enrolled (46 males, 32 females; mean age 68 years) of which 28.2 % exhibited reduced olfactory function (hyposmia) and 15.4 % exhibited loss of olfactory function (10.3 % functional anosmia, 5.1 % complete anosmia). Patients showed significantly lower olfactory performance compared to age- and sex-mated matched controls. Predictors of impaired olfactory function were age and NIHSS score. Self-reports indicated no significant differences between patients with normal olfactory function and those with reduced function. Yet, patients having an olfactory dysfunction rated odorous items as significantly less pleasant compared to patients without dysfunction.

Conclusions

Olfactory dysfunction seems to occur frequently after stoke even one year after initial admission. The deficits seem to relate to hyposmia and functional anosmia, and less to a complete loss of smell sensitivity.

Risk-Adapted Neoadjuvant Chemoradiotherapy in Rectal Cancer: Final Report of the OCUM Study

PURPOSE

We investigated whether neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer can be restricted to those at high risk of locoregional recurrence (LR) without compromising oncological outcomes.

PATIENTS AND METHODS

In a prospective multicenter interventional study, patients with rectal cancer (cT2-4, any cN, cM0) were classified according to the minimal distance between the tumor, suspicious lymph nodes or tumor deposits, and mesorectal fascia (mrMRF). Patients with a distance >1 mm underwent up-front total mesorectal excision (TME; low-risk group), whereas those with a distance ≤1 mm and/or cT4 and cT3 tumors in the lower rectal third received nCRT followed by TME surgery (high-risk group). The primary end point was 5-year LR rate.

RESULTS

Of the 1,099 patients included, 884 (80.4%) were treated according to the protocol. A total of 530 patients (60%) underwent up-front surgery, and 354 (40%) had nCRT followed by surgery. Kaplan-Meier analyses revealed 5-year LR rates of 4.1% (95% CI, 2.7 to 5.5) for patients treated per protocol, 2.9% (95% CI, 1.3 to 4.5) after up-front surgery, and 5.7% (95% CI, 3.2 to 8.2) after nCRT followed by surgery. The 5-year rate of distant metastases was 15.9% (95% CI, 12.6 to 19.2) and 30.5% (95% CI, 25.4 to 35.6), respectively. In a subgroup analysis of 570 patients with lower and middle rectal third cII and cIII tumors, 257 (45.1%) were at low-risk. The 5-year LR rate in this group was 3.8% (95% CI, 1.4 to 6.2) after up-front surgery. In 271 high-risk patients (involved mrMRF and/or cT4), the 5-year rate of LR was 5.9% (95% CI, 3.0 to 8.8) and of metastases 34.5% (95% CI, 28.6 to 40.4); disease-free survival and overall survival were the worst.

CONCLUSION

The findings support the avoidance of nCRT in low-risk patients and suggest that in high-risk patients, neoadjuvant therapy should be intensified to improve prognosis.

Suboptimal decision making by children with ADHD in the face of risk: Poor risk adjustment and delay aversion rather than general proneness to taking risks

OBJECTIVE

Suboptimal decision making in the face of risk (DMR) in children with attention-deficit hyperactivity disorder (ADHD) may be mediated by deficits in a number of different neuropsychological processes. We investigated DMR in children with ADHD using the Cambridge Gambling Task (CGT) to distinguish difficulties in adjusting to changing probabilities of choice outcomes (so-called risk adjustment) from general risk proneness, and to distinguish these 2 processes from delay aversion (the tendency to choose the least delayed option) and impairments in the ability to reflect on choice options. Based on previous research, we predicted that suboptimal performance on this task in children with ADHD would be primarily relate to problems with risk adjustment and delay aversion rather than general risk proneness.

METHOD

Drug naïve children with ADHD (n = 36), 8 to 12 years, and an age-matched group of typically developing children (n = 34) performed the CGT.

RESULTS

As predicted, children with ADHD were not more prone to making risky choices (i.e., risk proneness). However, they had difficulty adjusting to changing risk levels and were more delay aversive-with these 2 effects being correlated.

CONCLUSIONS

Our findings add to the growing body of evidence that children with ADHD do not favor risk taking per se when performing gambling tasks, but rather may lack the cognitive skills or motivational style to appraise changing patterns of risk effectively. (PsycINFO Database Record

Analysis of local recurrences after transanal endoscopic microsurgery for low risk rectal carcinoma

AIM

Rates of local recurrence (LR) after transanal endoscopic microsurgery (TEM) for rectal carcinoma vary; the reasons remain unclear. We analyzed LR after TEM for low-risk pT1 (G1/2/X, L0/X) rectal carcinoma to investigate the influence of completeness of resection and occult lymph node metastasis on risk of LR.

METHOD

LR location and stage, completeness of resection of primary carcinoma (minimal distance between tumor and resection line ≤1 mm vs >1 mm), and incidence of involved lymph nodes in resected LR specimens were collected, and tumor characteristics of LR were compared with primary carcinoma. Distant metastasis and overall and cancer-specific survival were determined.

RESULTS

LR developed in 14 patients; in 2/4 with R1/X resection, in 3/8 (38%) with clear margins (R0) but a minimal distance of ≤1 mm, and in 9/88 (10%) with formally complete resection. Six of nine patients with formally complete resection underwent radical surgery for LR; in five out of these six, lymph nodes were not involved. In 5/14 patients, LR was poorly differentiated compared to primary carcinoma. Main LR causes were incomplete tumor resection or tumor persistence after formally complete resection. Overall (p = 0.008) and cancer-specific (p < 0.001) survival was lower in LR patients compared to non-LR patients, even if lymph nodes were uninvolved.

CONCLUSIONS

The results suggest that most LRs after TEM for low-risk rectal cancer were caused by residual tumor at the previous excision site and not by undetected lymph node metastases. By improved standardization of surgical techniques to ensure complete resection of carcinomas and thorough pathological assessments, most LRs seem to be avoidable.

Longitudinal Changes in Familiarity, Free and Cued Odor Identification, and Edibility Judgments for Odors in Aging Individuals

This longitudinal study investigated changes in olfaction as assessed by a set of tasks requiring different aspects of semantic information in normal aging individuals. Using 16 odorous items from a standardized olfactory test, the Scandinavian Odor Identification Test, 107 middle aged and older adults were assessed up to three times over a period of 6.5 years, requesting them to rate familiarity and edibility for each odorous item before identifying it with or without presenting verbal cues. Using linear mixed models, the longitudinal analyses revealed significant correlations between all olfactory measures. Furthermore, we found an almost parallel age-related decline in all olfactory tasks, although free identification performance indicated a trend toward faster decline with age. Women showed less decline compared with men, in particular for edibility judgments. The results corroborate earlier cross-sectional findings showing significant correlations between the olfactory tasks. In the present study of healthy middle-aged and older adults, we found a parallel longitudinal decline across different tests of olfaction.

Long-term results of transanal endoscopic microsurgery after endoscopic polypectomy of malignant rectal adenoma

BACKGROUND

There is no consensus on the treatment and prognosis of malignant rectal polyps. The aim of the present study was to determine the role of transanal endoscopic microsurgery (TEM) after endoscopic complete polypectomy of malignant rectal adenomas with long-term follow-up.

METHODS

Of 105 patients with pT1 rectal carcinoma in 32 patients TEM followed complete endoscopic polypectomy while 73 had primary TEM. Local recurrence (LR), distant metastasis, overall and cancer-specific survival were determined by the Kaplan-Meier method.

RESULTS

Median follow-up was 9.1 years. In 32 patients with TEM following complete polypectomy no residual cancer was found. LR occurred in 3/28 (11%) patients with low-risk carcinoma (pT1 G1/2/X, L0/X, R0) and in 1/4 (25%) with high-risk carcinoma (pT1 G3/4 or L1). After primary TEM with complete resection (minimal distance >1 mm) LR occurred in 6/60 (10%) with low-risk carcinoma. After incomplete TEM resection (minimal distance ≤1 mm) LR occurred in 3/8 (38%) patients with low-risk and in 1/5 (20%) patients with high-risk carcinoma. Grading was the only significant risk factor for LR after endoscopic polypectomy followed by TEM (p = 0.002). At all outcomes did not differ between postpolypectomy TEM and primary TEM.

CONCLUSIONS

Patients with malignant rectal polyps removed by endoscopic polypectomy have a substantial risk of LR even if TEM of polyp site is cancer free. Risk of LR depends on tumor characteristics. In low-risk carcinoma long-term follow-up is necessary. The high LR rate in patients with high-risk rectal carcinoma restricts the use of TEM alone.

The Link Between Local Recurrence and Distant Metastases in Patients With Rectal Cancer

BACKGROUND/AIM

The relationships between local recurrence (LR), the development of distant metastases (DM) and prognosis in patients with rectal cancer remain unclear.

PATIENTS AND METHODS

In 606 patients who underwent curative resection, the role of LR was assessed retrospectively by time-dependent multivariate Cox models with inverse probability of treatment weighting taking into account competing risks.

RESULTS

Patients with LR had more DM than patients without LR (49/79, 62% vs. 86/524, 16.4%; p<0.001); 37% of LR-associated DM developed before or at LR, 63% after diagnosis of LR. Fifty-five percent of patients without DM at diagnosis of LR later developed DM. In these patients, the incidence of DM significantly exceeded the incidence in patients without LR. DM risk was most strongly associated with preceding LR and stage UICC III and II.

CONCLUSION

There is a causal link between LR and DM in patients with rectal cancer.

Incidence of childhood leukemia before and after shut down of nuclear power plants in Germany in 2011: A population-based register study during 2004 to 2019

The association between leukemia and proximity to nuclear-power-plants (NPPs) has been assessed in several countries with inconsistent results. A case-control study from Germany had shown an increased risk for childhood leukemia (diagnoses 1980-2003) near NPPs. Germany began shutting down nuclear reactors in 2011, following the Fukushima disaster. We tested whether the previously observed association between leukemia and proximity to NPP persisted despite the shutdown. We used an ecological study design to investigate the incidence of leukemia during 2004 to 2019 in children aged 0 to 14 years living near NPPs where at least one reactor was shut down in 2011. We defined study and control areas as municipalities whose surface area was at least 75% within 10 km or between 10 and 50 km of NPPs, respectively. We calculated age-standardized rates and incidence rate ratios (IRR) using control-areas as the reference. We also computed standardized incidence ratios (SIR) separately for each NPP using incidence rates of the German population as a reference. IRR decreased from 1.20 (95% confidence interval: 0.81-1.77) in 2004 to 2011 to 1.12 (0.75-1.68) in 2012 to 2019. Analyses of single plants showed an excess of childhood leukemia during 2004 to 2019 for the Unterweser-NPP, based only on three cases, and the Krümmel-NPP (n = 14; SIR: 1.98, 1.17-3.35). We found slightly decreasing of leukemia incidence rate ratios after the shutdown of nuclear reactors in 2011. Due to the small number of cases, risk estimates have large uncertainty. Further research including a longer follow-up is warranted. The consistent excess of incidence cases around Krümmel may require analytical epidemiological analysis.

Selection of patients with rectal cancer for neoadjuvant therapy using pre-therapeutic MRI - Results from OCUM trial

PURPOSE

No consensus is available on the appropriate criteria for neoadjuvant chemoradiotherapy selection of patients with rectal cancer. The purpose was to evaluate the accuracy of MRI staging and determine the risk of over- and undertreatment by comparing MRI findings and histopathology.

METHOD

In 609 patients of a multicenter study clinical T- and N categories, clinical stage and minimal distance between the tumor and mesorectal fascia (mrMRF) were determined using MRI and compared with the histopathological categories in resected specimen. Accuracy, sensitivity, specificity, positive predictive, and negative predictive value (NPV) were calculated. Overstaging was defined as the MRI category being higher than the histopathological category. mrMRF and circumferential resection margin (CRM) were judged as tumor free at a minimal distance > 1 mm. The chi-squared test or Fisher's exact test were used. P < 0.05 was considered significant.

RESULTS

The T category was correct in 63.5% (386/608) of patients; cT was overstaged in 22.9% (139/608) and understaged in 13.5% (82/608). MRI accuracy for lymph node involvement was 56.5% (344/609); 22.2% (28/126) of patients with clinical stage II and 28.1% (89/317) with clinical stage III disease were diagnosed by histopathology as stage I. The accuracy for tumor free CRM was 86.5% (527/609) and the NPV was 98.1% (514/524). In 1.7% (9/524) mrMRF was false negative.

CONCLUSION

MRI prediction of the tumor-free margin is more reliable than the prediction of tumor stage. MRF status as determined MRI should therefore be prioritized for decision making.

Influence of Local Recurrence and Distant Metastasis on Prognosis After Local Excision of Rectal Carcinoma

BACKGROUND

Influence of local recurrence (LR) on prognosis after a local excision (LE) for rectal cancer is unclear.

PATIENTS AND METHODS

A total of 152 patients were retrospectively assigned to one of three groups: Groups 1 and 2: complete and incomplete resection respectively, for low-risk carcinoma; group 3: high-risk carcinoma. We evaluated LR, distant metastasis (DM), overall survival, and cancer-specific survival (CSS).

RESULTS

LR rates were 10.4%, 43% and 29% for groups 1-3, respectively (p=0.002). In all three groups, DM incidence was low in patients without LR, but high in patients with LR (p<0.0001). Prior LR was an important risk factor for DM (hazard ratio: 14.1, 95% confidence interval=4.3-45.8, p<0.0001). DM significantly reduced CSS.

CONCLUSION

There is a strong association between LR and DM independently in the cause of LR. Avoiding LE for high-risk carcinoma and complete LE of low-risk carcinoma are essential to reduce LR and DM.

Trends in hospitalization of patients with diabetes mellitus in Ghana from 2012 to 2017 with predictions to 2032

BACKGROUND

This study explores sociodemographic and health factors associated with hospitalizing diabetes mellitus (DM) patients and estimates the number of future hospitalizations for DM in Ghana.

METHODS

We conducted a secondary analysis using nationally representative patient hospitalization data provided by the Ghana Health Service and projected population counts from the Ghana Statistical Service. Data were stratified by year, age, sex and region. We employed Poisson regression to determine associations between sociodemographic and health factors and hospitalization rates of DM patients. Using projected population counts, the number of DM-related hospitalizations for 2018 through 2032 were predicted. We analysed 39 846 DM records from nearly three million hospitalizations over a 6-y period (2012-2017).

RESULTS

Most hospitalized DM patients were elderly, female and from the Eastern Region. The hospitalization rate for DM was higher among patients ages 75-79 y (rate ratio [RR] 23.7 [95% confidence interval {CI} 18.6 to 30.3]) compared with those ages 25-29 y, females compared with males (RR 1.9 [95% CI 1.4 to 2.5]) and the Eastern Region compared with the Greater Accra Region (RR 1.9 [95% CI 1.7 to 2.2]). The predicted number of DM hospitalizations in 2022 was 11 202, in 2027 it was 12 414 and in 2032 it was 13 651.

CONCLUSIONS

Females and older patients are more at risk to be hospitalized, therefore these groups need special surveillance with targeted public health education aimed at behavioural changes.

Time trends, sociodemographic and health factors associated with discharge and length of stay of hospitalised patients with sickle cell disease in Ghana: a retrospective analysis of national routine health database

OBJECTIVE

Patients with sickle cell disease (SCD) are prone to multiple episodes resulting in frequent hospital visits. We determined the time trends, sociodemographic and health factors associated with length of stay (LoS) for patients with SCD in Ghana.

DESIGN, PARTICIPANTS, SETTING

We retrospectively analysed SCD hospitalisation records of 22 680 patients from a nationwide database of the Ghana Health Service from 2012 to 2017.

OUTCOME MEASURES

Factors associated with LoS were estimated using Cox regression, while the cumulative incidence of being discharged alive was estimated with in-hospital death as a competing risk.

RESULTS

Patients admitted for SCD over 6 years constituted 22 680 (0.8%) of nearly 3 million admissions. The median age and LoS for the patients were 16 years (IQR=8-24) and 3 days (IQR=2-4), representing 14 202 (62.6%) of the patients discharged alive by the third day. Patients with sickle cell anaemia (6139, 52.6%) with a crisis were more frequent than those without a crisis. Increasing age was associated with shorter LoS when comparing age groups 10-14 years (HR=1.08, 95% CI 1.01 to 1.14) and 25-29 years (HR=1.27, 95% CI 1.17 to 1.37) to patients aged 0-4 years. Patients with comorbidities had a longer LoS compared with those without (HR=0.88, 95% CI 0.86 to 0.90).

CONCLUSION

This is the largest study to date documenting factors associated with LoS for patients admitted for SCD. The association of younger age with increased LoS supports recent calls for early SCD screening, especially newborns. The emerging trends and factors accounting for SCD admission require a multisector approach as these patients already experience frequent episodes of pain and hospital visits.

Sociodemographic factors associated with time to discharge for hospitalised patients with asthma and asthma exacerbation using the Ghana Health Service District Information Management System 2 (DHIMS-2) database, 2012-2017

Objective

Data on asthma hospitalisations are a useful source of patient morbidity information. In Ghana, the length of stay (LoS) and sociodemographic factors of patients hospitalised for asthma and its exacerbation are understudied. We aimed to investigate the time to discharge and assessed factors associated with length of hospital stays of asthmatics in Ghana.

Methods

Retrospective analysis of hospitalised patient with asthma records between 2012 and 2017 from the nationwide Ghana Health Service District Health Information Management System 2 database. We calculated the cumulative incidence function for discharge stratified by age group and sex. Multivariable Cox regression was used to investigate the association of sociodemographic characteristics with the LoS.

Results

Of 19 926 asthma-associated hospitalisations, 730 (3.7%) were due to asthma exacerbation. Overall mean age was 34 years (SD=24.6), in 12 000 (60.2%) hospitalisations, patients were female. There were 224 deaths (1.1%). Median LoS was 2 days (IQR: 1–3) with almost 90% of all patients discharged by the seventh day. Age and region were among the covariates showing significant association with LoS. Age below 10 years (HR: 1.39 (1.11 to 1.78)) was associated with early discharge while comorbidity and health insurance ownership were associated with late discharge (p<0.001). LoS did not vary by sex. Compared with the Greater Accra region, patients in other regions had shorter LoS, especially the Ashanti and Upper West regions (p<0.001). LoS increased annually, but was highest in 2016 (HR: 0.94 (0.90 to 0.98)).

Conclusion

Disparities in LoS across regions, and an overall increasing annual trend in Ghana call for tailored healthcare resource allocation. Longer LoS implies that patients are often absent from school or work leading to substantial financial and emotional costs to individuals and families.

Impact of Cross-Linking Procedure on Perioperative Quality of Life in Keratoconus Patients

BACKGROUND

To evaluate the effect of crosslinking (CXL) with riboflavin for keratoconus (KC) therapy on quality of life (QoL): comparison of keratoconus patients with and without treatment.

METHODS

Prospective monocentric study. We recruited patients with progressive KC and with stable disease. Patients with progressive disease received cross-linking treatment; patients with stable disease were monitored. We compared QoL in both groups over 6 months and detected the influence of cross-linking treatment on QoL. QoL was assessed by NEI-VFQ-25, EQ-5D 5L, and EQ-Visual analog scale (VAS). In the evaluation of the Nei VFQ, the subgroups LFVFS and LFSES were calculated.

RESULTS

We enrolled 31 eyes of 31 patients in the intervention group and 37 eyes of 37 patients in the control group. Medians with standard deviations (SD) were calculated. All QoL-tests showed equal scores at baseline in both groups. At V2, one day after the treatment, EQ-VAS (56.4), LFVFS (57.4), and EQ5D5L (0.59) were significantly reduced. At V3 (one week after treatment), all results returned to baseline level. LFSES was not affected by the treatment. It remained stable (V2 85.4, V3 84.3). Comparing the baseline scores with the follow-up scores at month 6, we found a significant increase in QoL in all tests in the intervention group. Otherwise, the quality of life in the control group did not change over time.

CONCLUSIONS

Cross-linking led only to a short-term reduction in QoL. Although the treatment is painful for a few days, no effect on general quality of life LVSES has been demonstrated. QoL already returned to baseline after one week and the patients were not limited anymore.

Describing and Modeling the Burden of Hospitalization of Patients With Neoplasms in Ghana Using Routine Health Data for 2012-2017

The increasing cancer burden calls for reliable data on current and future associated hospitalizations to enable health care resource planning, especially in low- and middle-income countries. We provide nationwide estimates of the current and future burden of hospitalization because of neoplasms in Ghana.

Other data sets are useful to estimate epidemiologic trends in settings where cancer registries are not available.

Influence of Crosslinking on Astigmatism Vector in Keratoconus: A Vector Analysis

INTRODUCTION

Corneal cross linking (CXL) is an appropriate method to treat progressive keratoconus in order to stop progression. Generally, the change in the maximum corneal power (Kmax), corneal thickness, and total astigmatism are assessed for progression analysis. The aim of this study is to answer the question of whether corneal astigmatism is suitable for quantifying keratoconus progression or demonstrating stability. To improve accuracy, we analyze astigmatism as a vector parameter in CXL follow-up.

METHODS

We performed a retrospective observational study analyzing a total of 74 eyes diagnosed with progressive keratoconus that received CXL treatment and had a follow-up period of at least 12 months, and in some cases, up to 5 years. In the Scheimpflug imaging examination (Pentacam®), the focus was on the change of Kmax in diopter (D), astigmatism of the corneal front, and its vector parameter.

RESULTS

Preoperatively, we observed an increase in Kmax difference (KmaxD) (median +1.9 D ± standard deviation, SD 2.2) and astigmatism vector difference (AVD) (median +0.7 D ± SD 1.6) with a positive correlation, which establishes a treatment indication. The follow-up showed a stabilization of KmaxD and AVD after 12 months (median KmaxD -0.7 D, AVD -0.4), and over the periods of 3 and 5 years, a further stabilization of the curvature parameters with a lower number of cases.

CONCLUSIONS

Compared with an analysis of an absolute value only, the vector analysis of astigmatism allows a much more precise description of astigmatism in order to verify the effectiveness of CXL. Both astigmatism vector and Kmax preoperatively increased and stabilized potstoperatively. Astigmatism presumably has a significant effect on the quality of vision and should therefore also be used as an additional stability factor beside Kmax.