Optic Nerve Sheath Diameter Measurement During Diabetic Ketoacidosis: A Pilot Study

Optic Nerve Ultrasound Evaluation in Children: A Review

Managing patients with neurocritical illness requires monitoring and treating elevated intracranial pressure (ICP), especially in cases in children. In terms of precise and real-time measurements, invasive ICP measurements are presently the gold standard for the initial diagnosis and follow-up ICP assessments. As a rapid and non-invasive way to detect elevated ICP, point-of-care ultrasonography (POCUS) of optic nerve sheath diameter (ONSD) has been proposed. The utility of bedside POCUS of ONSD to detect elevated ICP with excellent diagnostic test accuracy in adults has already been demonstrated. Nonetheless, data on the relationship between POCUS of ONSD and ICP in children are scarce. Therefore, the purpose of this review is to point out the most recent findings from the pediatric published literature and briefly discuss what was assessed with ONSD ultrasound examination, and also to describe and discuss the diagnostic procedures available for optic nerve ultrasound appraisal. A search of the medical databases PubMed and Scopus was carried out. The terms such as "ocular ultrasonography", "ICP assessment", "children", "point-of-care ultrasound", and "POCUS" were searched. In conclusion, the use of the standardized A-scan technique coupled with the B-scan technique should be suggested to provide data that are as accurate, precise, repeatable, and objective as possible.

Sonographic Optic Nerve Diameter and Clinical Biomarkers in Patients With Poorly Controlled Diabetes: A Comparative Analysis With Nondiabetic Subjects

Objective:

The study assessed optic nerve diameter (OND) and clinical biomarkers in patients with poorly controlled diabetes compared with healthy nondiabetic volunteers.

Materials and Methods:

There were 1320 adult participants recruited to the study. The cohort was divided into 600 Type 2 diabetic (DM II) patients and 720 apparently healthy, nondiabetic volunteers. The OND was measured using a high-resolution dedicated ultrasound device (Sonoace 5500; Medicol, Medison, Miami, FL, USA) with a 10-MHz linear array transducer. Subjects were examined in a supine position with their eyes closed. Three measurements of the OND were taken and the average recorded. Hemoglobin A1c concentration and lipid profiles were determined using Bio-Rad Diamat analyzer (Bio-Rad, Hercules, CA). Body mass index and age were matched for both cohorts for comparativeness.

Results:

The mean OND of the DM II patients was 3.10 ± 0.14 mm (range of 2.6–4.0 mm), which was significantly ( P < .05) lower than the control volunteers (4.22 ± 0.15 mm). The OND demonstrated a negative significant correlation with HA1c, duration of diabetes and low-density lipoprotein cholesterol level ( P < .05). Lipid profiles, blood urea, serum creatinine, and hemoglobin A1c showed statistical difference between diabetics and control subjects.

Conclusion:

Poorly controlled DM II patients may have significantly narrower OND than nondiabetic patients. This imaging biomarker has the potential to transform visual care for DM II patients.

Diagnostic Applications of Point-of-Care Ultrasound in Pediatric Emergency Medicine

Point-of-care ultrasound has become an essential part of pediatric emergency medicine training and practice. It can have significant clinical benefits, including improving diagnostic accuracy and decreasing length of stay, and does not require radiation exposure for patients. In this review, we summarize the current diagnostic point-of-care ultrasound applications in pediatric emergency medicine, their evidence, and techniques.

Bedside sonographic measurements of optic nerve sheath diameter in children with diabetic ketoacidosis

BACKGROUND

Bedside sonographic assessment of the optic nerve sheath has gained popularity for evaluating intracranial pressure in recent years.

OBJECTIVE

To investigate the bedside sonographic measurements of optic nerve sheath diameter (ONSD) and ONSD/eyeball diameter ratios, which are related with cerebral edema (CE), in children with diabetic ketoacidosis (DKA) before and after treatment.

METHODS

Children aged 12 months to 18 years, who were diagnosed with DKA were included. The ONSD was measured at 3 mm posterior to the globe in the anterior axial transbulbar view. The eyeball transverse diameter (ETD) and eyeball vertical diameter (EVD) were measured and ratios of ONSD/ETD and ONSD/EVD were calculated. Bedside ultrasound (US) examinations were performed at the beginning and at the end of fluid therapy.

RESULTS

About 43 patients were enrolled. About 12 (27.9%) patients had mild, 14 (32.6%) moderate, and 17 (39.5%) severe DKA. At baseline, the ONSD measurements and ratios were significantly higher in severe DKA group than in those with mild or moderate DKA group. All ONSD measurements, ONSD/ETD, and ONSD/EVD ratios at the end of therapy were significantly lower compared with baseline measurements. At the end of therapy, ONSD measurements and ratios were similar among DKA severity groups.

CONCLUSION

The ONSD measurements and ratios decreased from the beginning of DKA treatment, which could be considered as an indicator of an increase in intracranial pressure at the time of admission. Ocular US may serve as a promising tool to perform further risk stratification of children with DKA and to identify DKA-related CE.

The measurement of ultrasonographic optic nerve sheath diameter in patients with hyperglycemia

Background:

Diabetes mellitus is a disease associated with several complications in its acute and chronic stages.

Objective:

The aim of the study was to determine the treatment-associated changes in optic nerve sheath diameter in patients admitted to the emergency department due to one of the acute hyperglycemic complications of diabetes mellitus.

Materials and method:

Diabetic patients with serum glucose levels of 250 mg/dL or higher were included in the study. Healthy volunteers were included in the control group. Optic nerve sheath diameter was measured at 0th hour and at the end of the second hour. Blood samples were collected simultaneously with optic nerve sheath diameter measurements.

Results:

The study included 100 individuals. Group 1 included 50 patients and Group 2 included 50 healthy adults. Optic nerve sheath diameter was 4.5 ± 0.4 mm in Group 1 and 4.4 ± 0.5 mm in Group 2 in 0th hour, and no statistical difference was found between the groups (p = 0.162). In Group 1, optic nerve sheath diameter increased 0.6 ± 0.4 mm after the treatment. Of the patients in Group 1, 22 (44%) patients with diabetic ketoacidosis or hyperosmolar hyperglycemic state were assigned to Group 1A and 28 (56%) patients with isolated hyperglycemia were assigned to Group 1B. There was not a difference between the pre- and post-treatment optic nerve sheath diameter values of the patients in Group 1A and Group 1B. Optic nerve sheath diameter was observed to enlarge after treatment. The difference in optic nerve sheath diameter was 0.6 ± 0.4 mm in Group 1A and 0.5 ± 0.4 mm in Group 1B (p = 0.294).

Conclusion:

Pre-treatment optic nerve sheath diameter values of the patients who were diagnosed with one of the acute hyperglycemic complications of diabetes mellitus are not different from healthy adults. Furthermore, optic nerve sheath diameter values do not change with the severity of the disease. However, optic nerve sheath diameter values change with treatment. For this reason, optic nerve sheath diameter can be used to following the development of brain edema.

Determination of cerebral edema with serial measurement of optic nerve sheath diameter during treatment in children with diabetic ketoacidosis: a longitudinal study

Background Cerebral edema is a fatal complication that can occur in children with diabetic ketoacidosis (DKA). Its clinical signs are generally not explicit, and subclinical cerebral edema can occur. This study is one of the few longitudinal studies conducted to identify cerebral edema in patients with DKA by measuring the optic nerve sheath diameter (ONSD). The aim of this study was to investigate cerebral edema in children with DKA with serial measurement of ONSD, which is an early and reliable indicator of cerebral edema, and to monitor changes in ONSD during therapy. Methods The study was conducted by measuring ONSD ultrasonographically at baseline and during the course of therapy in patients with DKA. All participants were diagnosed and received therapy at our unit between May 2016 and June 2017. The study was registered with the Clinical Trials database, with a study number of NCT02937441. Measurements were obtained while the patients were in the supine position with their eyes closed, and axial transbulbar images of both eyes were obtained with a 6-15-MHz linear probe. Results The ONSD values of children with DKA changed during the treatment, reaching the highest values at 12-16 h of therapy, and the greatest ONSD was observed in children who had moderate and severe DKA. Conclusions During treatment of children with DKA, it is possible to predict cerebral edema by measuring ONSD, and this may contribute to clinical management, especially fluid treatment.

Measurement of corneal thickness, optic nerve sheath diameter and retinal nerve fiber layer as potential new non-invasive methods in assessing a risk of cerebral edema in type 1 diabetes in children

AIMS

Some patients with diabetic ketoacidosis develop cerebral edema (CE) in the course of type 1 diabetes mellitus (T1D), which may result in central nervous system disorders and high mortality. The imperfection of existing neuroimaging techniques for early recognition of CE forces us to search for the new and non-invasive methods. The aim of the study was to assess the usefulness of new methods (pachymetry, transorbital ultrasonography-USG, optical coherence tomography-OCT study) in the assessment of the risk of CE occurrence in children with newly diagnosed T1D.

METHODS

The study group included 50 children with newly diagnosed T1D, 54 patients with long-term T1D as a reference group and 40 children without glucose tolerance disorders as controls. In all subjects, a corneal thickness (CCT) index with pachymeter, optic nerve sheath diameter (ONSD) using transorbital USG and retinal nerve fiber layer (RNFL) during OCT study were measured and compared with selected clinical parameters of T1D.

RESULTS

In patients from a study group at onset of T1D, the higher CCT (p < 0.001) and ONSD (p < 0.001) values were observed as compared to the results obtained after 48 h of metabolic compensation. The ONSD correlated negatively with pH value (r = - 0.64; p < 0.001), BE (r = - 0.54, p < 0.001) and HCO^3- (r = - 0.50; p < 0.001). A positive correlation between RNFL and Na⁺ levels (r = 0.47; p < 0.005) was also observed.

CONCLUSIONS

Transorbital USG and pachymetry may serve as the potential promising methods for the non-invasive assessment of the increased risk of development of CE in patients with T1D.