Efficacy of unanesthetized spiral computed tomography scanning in initial evaluation of childhood leukocoria

Coats' syndrome: long term follow up

AIM

To increase the understanding of the long term results in pseudo-retinoblastoma eyes with infantile Coats' syndrome.

METHODS

This study design was a retrospective case review. 10 patients were analysed who were initially referred with a diagnosis of retinoblastoma but had Coats' syndrome on the basis of ocular oncological evaluation. Vision, fundus photography, ultrasonography, and computed tomography scans were obtained and evaluated. Changes in vision and retinal status were measured.

RESULTS

The initial age at presentation was 2.4 years (range 0.25-4 years). All patients had retinal detachment at diagnosis. Nine of 10 retinas were reattached after various treatments. Reattached retinas had closure of peripheral telangiectasia and visible intraretinal crystals. Vision was dismal. At last follow up (mean 8.8 years), only two patients had 20/400 or better visual acuities. Five eyes had no light perception despite early treatment to reattach the retina. Nine of 10 eyes remain cosmetically acceptable. One patient wore a cosmetic shell.

CONCLUSIONS

Long term results indicate that these eyes can be salvaged and the retina reattached but the visual outcome is poor.

Orbital helical computed tomography in the diagnosis and management of eye trauma

OBJECTIVE

To prospectively determine the accuracy of helical computed tomography (CT) and multiplanar reconstruction and its value in surgical planning for the management of ocular trauma with suspected intraocular and orbital foreign bodies using surgical and clinical follow-up findings as the gold standard.

DESIGN

Prospective, observational case series.

PARTICIPANTS

Thirty-six patients with ocular trauma and suspected foreign bodies were studied.

INTERVENTION

All patients were examined using a standardized scanning protocol with helical CT direct scanning in the axial plane and multiplanar reconstruction of coronal and sagittal planes.

MAIN OUTCOME MEASURES

The images were analyzed for the presence and number of intraocular and orbital foreign bodies, anatomic location, and foreign body size. The surgical and clinical follow-up findings (contact lens examination, gonioscopy, indirect ophthalmoscopy and scleral depression, perimetry, color testing, measurement of size) were used as the gold standard to which the image results were compared.

RESULTS

Helical CT showed a single intraocular foreign body in 14 patients, a single orbital foreign body in 9 patients, and multiple orbital foreign bodies in 2 patients. Intraocular or orbital foreign bodies were excluded in 11 patients. Twenty foreign bodies were correlated with surgical results. Surgical and clinical follow-up findings were in agreement with helical CT results regarding the detection and determination of the number of presumed foreign bodies. Localization to intraocular versus orbital compartment and proximity to the optic nerve was accurate in all patients. Determination of size of the foreign bodies on the helical CT images was reliable and repeatable.

CONCLUSIONS

Helical CT axial scanning with multiplanar reconstruction is accurate at detecting and localizing intraocular and orbital metallic, glass, and stone foreign bodies. This imaging method aids the surgeon in choosing the surgical approach to retained intraocular and orbital foreign bodies.

CT of soft tissue injury and orbital fractures

Complex orbital rim and fractures of the internal orbital skeleton (orbital walls) are best analyzed by high-resolution axial CT. Optic canal fractures are optimally visualized with thin 1-mm section high-resolution CT scanning. Spiral CT may be used in the acutely injured patient because of its rapid scan technique. This spiral technique provides smooth data sets for three-dimensional reformations and may demonstrate foreign bodies in more than one plane. Another advantage of spiral CT is the capability of CT angiography. MR imaging usually is not the initial modality for the assessment of orbital trauma, but it is helpful in evaluating vascular injuries such as carotid-cavernous sinus fistulas or post-traumatic pseudoaneurysms. In general, CT with contrast injection is not necessary except when traumatic vascular anomalies, such as carotid cavernous, dural fistulas, or thrombosis of the superior ophthalmic vein, are considered in the differential diagnosis.

Coats' disease and persistent hyperplastic primary vitreous. Role of MR imaging and CT

Coats' disease is an idiopathic disorder in which telangiectatic and aneurysmal retinal vessels leak a lipoproteinaceous exudate, with consequent bullous retinal detachment. It is a diagnostic challenge, and CT and MR imaging provide valuable information to differentiate it from other pathologies, particularly from retinoblastoma. Typical, advanced Coats' disease shows on CT a denser substance posterior to the vitreous, which on MR is hyperintense on all pulse sequences. Contrast administration on both CT and MR might give slight linear enhancement at the boundary between vitreous and exudation. Persistent hyperplastic primary vitreous (PHPV) is a unilateral disorder in a microphthalmic eye, seen in full-term infants. PHPV rarely is bilateral in patients with Norrie's disease, Warburg syndrome, or patients with retinal dysplasia. Persistent fetal vasculature leads to fibrosis, resulting in elongation of the ciliary processes, retinal detachment, and spontaneous cataracts. The CT appearance in the disorder is quite variable; however, MR imaging may be superior in demonstrating the enhancing retrolental mass and the elongated ciliary processes.

Evaluation of intraocular foreign bodies by spiral computed tomography and multiplanar reconstruction

OBJECTIVE

This study aimed to evaluate the ability of spiral computed tomography (CT) and multiplanar reconstruction in the assessment of intraocular foreign bodies.

DESIGN

The study design was experimental.

MATERIAL

Three foreign bodies (metal, glass, and plastic) implanted into the globe of a cadaveric head were studied.

INTERVENTION

Spiral CT in the axial plane was used. Beam collimation and table increment were both 3 mm, whereby overlapping axial slices were reconstructed at 1-mm intervals. The data were transferred to a workstation, and reconstructions in the coronal and sagittal plane were performed.

MAIN OUTCOME MEASURES

The ability to detect and evaluate localization, shape, and size of the foreign bodies in all three imaging planes was assessed.

RESULTS

All foreign bodies were detected in the axial and in both reconstructed planes. The metal foreign body caused imaging artifacts in the axial plane. In the reconstructed planes. imaging artifacts were less severe, and evaluation of localization and shape was improved. Glass and plastic foreign bodies were well seen in all planes, and shape and localization were well demonstrated. Appropriate window settings improved determination of size of the different foreign bodies.

CONCLUSIONS

Spiral CT of the orbit and multiplanar reconstruction offers a promising tool for evaluation of intraocular foreign bodies. Advantages of spiral CT compared to conventional CT are data acquisition in only one axial plane; shortened examination time; reduced radiation exposure; reduced imaging artifacts from metallic foreign bodies in the reconstructed planes; and demonstration of localization, shape, and size of the foreign body in three imaging planes.

Detection and localization of steel intraocular foreign bodies using computed tomography. A comparison of helical and conventional axial scanning

PURPOSE

To compare the sensitivity and specificity of detection, and accuracy of localization, of small steel intraocular and episcleral foreign bodies, using conventional axial and helical computed tomographic scanning in an experimental model.

METHODS

Small steel foreign bodies ranging in size from 0.048 to 0.179 mm3 were placed in intraocular and episcleral locations in eye bank eyes mounted in the orbits of a human skull and scanned using helical and conventional axial techniques. Helical scanning was performed using 1-mm and 3-mm thick sections. Conventional axial scanning was performed using 3-mm thick sections. Images were reviewed by masked observers to determine sensitivity, specificity, and accuracy of localization for each imaging method.

RESULTS

Steel foreign bodies as small as 0.048 mm3 were detectable with each scanning protocol. Although the helical scans appeared to provide higher levels of sensitivity compared to conventional axial scanning, the difference in outcome between the scan types was not statistically significant. Sensitivity was dependent on the size of the foreign body and ranged from 45% to 65% for the smaller ones (< 0.06 mm3) to 100% for the larger ones (> 0.06 mm3). Multiplanar reformatting of images was helpful in achieving optimal accuracy.

CONCLUSION

In an experimental model of steel intraocular foreign body, helical computed tomographic scanning provided images of high quality similar to that of conventional axial scanning.