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Background: Despite the improvement in diagnostic technologies, imaging of intraocular foreign bodies (IOFB) located in the projection of the ciliary body remains one of the current problems of ocular traumatology., Purpose: To study the possibilities of imaging intraocular foreign bodies in the projection of the ciliary body by infrared transpalpebral transillumination (IRTT)., Materials and Methods: 10 patients (10 eyes) with a penetrating eye wound and the presence of an IOFB were enrolled in the study. X-ray diagnostic testing, ultrasound examination of the eye and IRTT were performed in all patients., Results: In all patients, the IRTT revealed the shadows of the Pars plana and Pars plicata of the ciliary body on the sclera as well as the shadow of an IOFB., Conclusion: The technique of IRTT in patients with penetrating eye injury allows non-invasive imaging of IOFB in the projection of the ciliary body and identification of their localisation., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Georg Thieme Verlag KG Stuttgart · New York.)

Aim: To judge the possibilities of detection of orbital foreign bodies in multidetector CT (MDCT) with a focus on glass slivers., Materials and Methods: Experimental systematic measuring of Hounsfield Units (HU) of 20 different materials, containing 16 different types of glass with 4 different types of ophthalmic lenses among them. The measurements were performed using a standardized protocol with an orbita phantom being scanned with 16-slice MDCT. Using the resulting density values, the smallest detectable volume was calculated. Using this data we produced slivers of 5 different glass types in the sub-millimeter range and calculated their volume. Those micro-slivers underwent another CT scan using the same protocol as mentioned above to experimentally discern and confirm the detection limit for micro-slivers made of different materials., Results: Glass has comparatively high density values of at least 2000 HU. The density of glasses with strong refraction is significantly higher and reaches up to 12 400 HU. We calculated a minimum detectable volume of 0.07 mm (3) for glass with a density of 2000 HU. Only glass slivers with a density higher than 8300 HU were experimentally detectable in the sub-millimeter range up to a volume as small as 0.01 mm (3). Less dense glass slivers could not be seen, even though their volume was above the theoretically calculated threshold for detection., Conclusion: Due to its high density of at least 2000 HU, glass is usually easily recognizable as an orbital foreign body. The detection threshold depends on the object's density and size and can be as low as 0.01 mm (3) in the case of glass with strong refraction and thus high density. The detection of glass as an orbital foreign body seems to be secure for slivers with a volume of at least 0.2 mm (3) for all types of glass., (© Georg Thieme Verlag KG Stuttgart · New York.)

Conjunctivitis is a frequent disease mostly caused by infections. In the case of a single-sided manifestation and additional resistance to anti-infective therapy a widespread differential diagnosis has to be considered. The case report of a 41-year-old patient suffering from unilateral persistent conjunctivitis is presented. Initially, there was no biomicroscopic evidence for a penetrated ocular foreign body. The unilateral, chronic and sectoral conjunctivitis was resistant to topical application of antibiotics and steroids. After repeated in-depth anamnesis the patient recalled an inconsiderable trauma while he was working on a building site. High-frequency ultrasound was used to locate an intrascleral foreign body 3 mm behind the limbus corneae while slit lamp biomicroscopy and ophthalmoscopy failed to detect the foreign material. The precise localisation provided by the 20-MHz sector scanner optimised the management of operative intervention and consequently led to an uncomplicated extraction of the bulbar foreign body.

Background: Small intrascleral foreign bodies of different materials, especially plastic or organic, can sometimes not easily--or not at all--be detected by routine X-ray examination or computed tomography scan. The aim of our study was to evaluate the usefulness of ultrasound biomicroscopy (UBM) with regard to the detection and localisation of such foreign bodies., Methods: An in vitro study with the preparation of a scleral tunnel on 12 porcine eyes was performed. Small foreign bodies of different types of material were placed in the tunnel. The UBM was performed with a Humphrey Ultrasound Biomicroscope, Model 840, to evaluate its diagnostic value in detecting and specifying these sclera-covered foreign bodies., Results: Even small foreign bodies of the anterior ocular segment of only 200 microm in size can be detected with the UBM due to the typical ultrasound patterns and artifacts. However, there is no diagnostic specificity for the corresponding material., Conclusion: The UBM is a high-frequency ultrasonic device with an imaging depth of 5 mm and a spatial resolution of 100 microm. Therefore it is a useful alternative or, respectively, additional diagnostic tool to common imaging techniques like routine X-ray imaging or CT scans, especially in the detection of non-metallic objects. It can provide important information for the ophthalmic surgeon with regard to pre-operative evaluation of the eye. Furthermore, the UBM might even substitute operative exploration of foreign bodies if they are located in the anterior segment of the eye.

Background: Orbital foreign bodies constitute an interdisciplinary challenge, diagnosis being especially difficult because of inconspicuous entrance orifices. Indication for the removal of an orbital foreign body has always to be decided upon individually taking into account the benefits and risks resulting from an operation. The latter is particularly indicated if there are acute and chronic functional restrictions or inflammatory reactions either present or to be expected. The objective of our study was to produce systematic guidelines concerning the therapeutic procedure of dealing with orbital foreign bodies with a view to a benefit-risk assessment., Patients and Methods: Over the last ten years ten patients with an orbital foreign body were treated in our Department, four of them requiring acute attention. CTs were taken of all patients. Only in one case additional MRTs were produced. Eight out of ten patients underwent operation, of which seven resulted in a complete removal of the foreign body. In the case of two patients we decided against an operation after interdisciplinary consultation., Results: In our view the imaging--providing diagnostics by means of computer tomography is the most promising method for determining a foreign body in the orbit. Decision for an operative removal of a foreign body was invariably taken interdisciplinary in cooperation with an ophthalmologist. Surgical approach was chosen in accordance with the localisation of the foreign bodies. None of the patients suffered from a loss of vision or a restriction of functions as a result of the operation., Conclusions: In the indication the foreign material is of essential importance. Orbital foreign bodies that have been present in the tissue for a longer time can be allowed to stay, unless loss of functions are progressive. Loss of vision always being a consequence of the initial trauma.

Orbital injuries may be associated with the presence of foreign bodies in which long retention leads to damages such as loss of vision or cerebral abscess. We present the case of a 21-year-old male patient that developed ptosis, limitation of movements and an inflammatory reaction in the right eye after being hit by a tree branch. A CT scan of the orbits revealed an increased density in the right orbital cone. After the neurosurgical approach for the removal of the foreign body, a wooden fragment measuring 2.0x0.3 cm, the patient had a good outcome without visual deficits, ptosis regression and resolution of the inflammatory process. The postoperative CT scan didn't identify any remaining foreign body fragment. This case calls attention to the fact that the wooden splinter presented on CT scan with high density (136 HU) two months after the trauma and was removed by a supraorbital craniotomy.

Patient: A 32-year-old male had an injury of his right eye by hot liquid plastic (Ultradur R). Intraoperatively, the eye was found broadly penetrated and filled up by more than 50% with ragged pieces of plastic. Computed tomography three days after wound closure revealed remaining foreign body material. As function was totally lost no further operation was considered. Seven weeks after the trauma, the eye was enucleated because of a painful phthisis. Histology showed numerous giant cells., Conclusions: Hot liquid plastic may perforate the eye and fill it up to a great extent. Due to intraocular cooling, pieces with sharp edges may develop, thus producing further (mechanical) tissue damage. Intraocular plastic is able to induce a massive foreign body reaction. It may be detected easily by computed tomography.

Background: Small metallic foreign bodies may easily be identified by conventional x-ray. The Comberg shell is a useful tool to discriminate between extra-respectively intraocular localization of the foreign body. However, poor results are common when evaluating the x-ray films., Methods: We have improved evaluation of the radiographs by means of a program for a personal computer, regarding the following aspects: To avoid errors of measurement the relevant points of the radiograms are read by a digitizer-tableau. The different projection failure of the lateral respectively posteroanterior x-ray is calculated separately. For the calculation of the modell the true axial length of the eye is considered., Conclusion: A three dimensional image from varying points of view gives an instructive impression of the foreign body and its relation to structures of the eye. Handling of the presented computer program is easy. It standardizes analysis of the Comberg radiograms.

Princips of computer tomography is demonstrated and the absorption coefficients of ocular and orbital tissue are calculated. The advantages and disadvantages of this procedure are discussed. 39 patients with ocular and orbital diseases were examined by computer tomography. The main indication was tumors, including metastases and diseases arising from ethmoidal cells. Vascular anomalies and tumors were better demonstrated by angiography. Dislocated lens, enlarged tumors of the choroid and prostheses (cerclage and orbital implants) are demonstrable. In contrast to echography, the computer tomography gives certainly better results in the posterior part of the orbit. Technical improvement of the apparatus could lead to a wider use in ophthalmology.

In the study reported here it was demonstrated that with computerized tomography (CT) it is possible to find metallic foreign bodies in the orbit (especially within the eyeball) and to locate them accurately. Moreover, with CT the risks both of intraocular infection and explusive hemorrhage in perforating eye injuries prior to initial surgical treatment are reduced. Further loss of aqueous humor and additional damage to intraocular tissue are also avoided.

The series comprises 27 patients examined by CT to detect, locate or exclude a foreign body. 22 of them actually had an orbital foreign body. In three cases CT was the primary method and showed the foreign body correctly, while in 18 it was first detected in plain films and CT was performed to locate it. 20 metallic foreign bodies were hyperdense in appearance. Two cases had wooden foreign bodies, one with a density of +10 HU and the other hypodense with a value of about -434 to -446 HU. The latter piece of wood was first interpreted falsely as a bubble of gas. The results proved that the detection of metal is easy, but differentiation between wood and gas is problematical. Experiments conducted to determine the CT densities of different pieces of wood gave results varying from -618 HU to +23 HU. The highest densities obtained for glass varied from +522 HU to +2000 HU. The density of a plastic lens was -105 HU.

An intralental metallic foreign body was identified by computerized tomography and removed by extracapsular cataract extraction. A Simcoe posterior chamber lens was implanted without any problem. The problems of lens implantation in younger patients are pointed out.

The X-ray localization of intraocular foreign bodies is based on an average-sized schematic eye. Whether or not a foreign body only reached or penetrated the rear wall of the bulbus often cannot be decided safely - even if X-ray checks included other than straight forward gaze directions. By means of ultrasound it is possible. 1. to measure exactly the real dimensions of the patients eye and to alter the X-ray localization scheme (W. Comberg's scheme) correspondingly. This improves the accuracy of the X-ray localization technique. 2. To localize the foreign body directly and exactly by presentation of its echo. Simultaneous presentation of the bulbus rear wall echo permits determination of the foreign body position. - A case record is given.