Ординатура / Офтальмология / Английские материалы / Retinal and Vitreoretinal Diseases and Surgery_Boyd, Cortez, Sabates_2010

In coroidal lesions the size is important. Cohen et al.(12) determined that lesions < 2 mm had a diagnosis efficiency of 40%, while in the case of larger lesions > 4 mm the performance was 90%. Augsburger reported that diagnosis in small coroidal lesions is only 64,7%.(17)

Part of the harvested material is spread on a glass plate and fixed with 95% alcohol and air dried. Afterwards routine staining is done and the rest of the material remaining in the aspiration needles is introduced in a balanced HANKS solution (5% acetic acid and alcohol). Later this is processed for cyto diagnosis (PAP-GIEMSA) and for procedures that require special staining (musine and melamine, immunohistochemistry, electronic microscopy,

cytometry and cellular block analysis). The other part of the aspirated material is mixed with phosphate buffer solution and prepared for posterior analysis with techniques for chromosomal determination.(6,8,9,13,14,15)

The novel preparation technique used in gynecologicaltumors,isamonolayertechnique that allows the grouping of cells in such a way that you obtain a monolayer of cells that simulate a tissue layer (two step cyto concentration, filtering, vortex disintegration, sealing and marking). The sample is put on glasses that form a monolayer of thin smear; due to an electric charge, a circle of 13 mm diameter is formed, with a mean cellular concentration of 60.000 cel./mm2 (18) (Figure 4).

Prognostic Factors

In terms of uveal melanomas, diverse prognostic factors exist which can be obtained through the histopathologic study and the DNA from the tumor, which can be favorable or unfavorable for the clinical evolution of the patient. The most important are:

595

Cellular proliferation: The methods to study it include:

1.Miotic Index: very difficult to determine, only cells in mitosis are acceptable.

2.Fluid Cytometry: quantifies DNA and in synthesis.

•Type of cell.

•Cellular proliferation.

•Lymphocyte and macrophage infiltration.

•Chromosome characteristics (chromosome 3 monosomya).

Type of cell: Fusiform A, Fusiform B, Small or big epitheloid, mixed.

3.Immunohistochemistry:(MIB-1),ki-67(anti- proliferative activity).(19)

Lymphocyte and macrophage infiltration:

Reduction in the patient́survival has been associated to a high degree of lymphocitary infiltration in the tumor.(20)

While infiltration with T lymphocytes is linked to death due to methastasis.(21)

On the other hand, the mortality index raises to the extend of the increase of the macrophage infiltration CD 68+(22) (Figure 5).

Chromosome 3 monosomy: For the genetic assessment of uveal melanomas a FISH (fluorescent in situ hybridization) method is used.

It has been determined that heterogenicity of chromosome 3 monosomy is a frequent phenomenon in this type of tumors.(23) Other studies showed on the follow-up of patients with uveal melanomas and chromosome three monosomy, a 53% methastasis development in a period of up to 3 years.(24)

In the study where we obtained the specimen through APFV, we needed to know which prognosis factors were distributed homogenously, because if they were not, then only the positive results were significant and the negative ones were mistaken. The prognosis factors with heterogenic expression are:

•Type of cell (epithelial cell pocket);

•Size of the nucleolus;

•Lymphocitary infiltration;

•Vascular network and neovessels;

•Chromosome 3 monosomy;

•Others.

Conclusions

In certain cases of intraocular tumors the diagnosis canot be made with conventional methods and it is necessary to harvest a sample of tumor cells. The aspiration puncture

with a thin needle (25 gauge or <) is a safe technique with a relatively low percentage of complications that leads to a definite diagnosis in more than 95% of the cases.

The recent use of FISH for chromosomal characterization of uveal melanomas has increased the indication for this technique as a prognosis and follow-up factor for these patients; but the lack of homogeneity in the distribution of the chromosome has limited its value.

References

Intraocular foreign bodies (IOFBs) are present in a significant percentage of penetrating ocular injuries and may result in severe visual loss. Most of cases are work-related and seen in young, male patients.

The most frequent complications are lens injury, endophthalmitis, retina lesion or detachment and proliferative vitreoretinopathy (PVR).

Afocused history and ophthalmic examination are critical to formulate an effective plan. Operative considerations include timing of surgery (delayed versus immediate), primary cataract extraction versus lensectomy, route and instrument used for IOFB extraction, and the role of intraoperative antibiotics.

The aim of this review is providing guidelines for the management of IOFBs.

Traumatic eye injuries with IOFBs may result in severe visual loss depending on the mechanism of injury, size and location of the IOFB, and the occurrence of postoperative endophthalmitis and retinal detachment with PVR.

Clinical diagnosis of endophthalmitis may be difficult in these cases since signs of infection may be masked by the trauma damage.

In a review of ocular trauma from the United States Eye Injury Registry, 25% of patients with IOFB injury had final visual acuities of less than 20/200, despite advances in surgical techniques.

IOFBs are present in a significant percentage of penetrating ocular injuries.(1)

The majority of IOFBs are metallic. Other IOFB body matters are concrete, wood and glass. The most common activities at the time of injury are hammering and chiselling.

The entry site is usually corneal and corneoscleral (Figure 1). And the vitreous cavity is the most common final location of the IOFB. A review of the National Eye Trauma System documented the vitreous as the final location in the 47% of IOFB injuries, retina in 33%, pars plana /ciliar body in 5%, lens in 5%, and the anterior chamber (AC) in 10% (Figure 2).

The most common clinical features at the time of presentation are lenticular changes and vitreous haemorrhage. Other presentations as relative afferent pupillary defect, hyphema, uveal prolapse and retinal detachment, are associated with poor visual outcome. Vitreous haemorrhage and poor visual acuity at the time of presentation are also factors predicting poor visual outcome (Figure 3).

The most frequent complications are lens injury, endophthalmitis, retina lesion or detachment and PVR.

Reinterventions are frequently needed. Mean number of operations in most of series is 1.5-2.

Toxicity of metallic IOFBs is more closely related to the active surface are than the volume of the IOFB. Siderosis is caused by the interaction between trivalent iron ions and the proteins in the eye’s epithelial cells. Usually, siderosis is developed after some years of ferrous IOFB presence and can be proved by electroretinography (ERG) changes and visual acuity (VA) decrease, that seem to be reversible after IOFB removal.

Chalcosis can start as a rapid, sterile, endophthalmitis-like reaction. Untreated, this violent response may lead to loss of vision within a few hours. After a prompt pars plana vitrectomy (PPV) with IOFB removal, ERG usually improves and good visual acuity can remain.(2)

The percentage of patients using eye protection is fewer than 10% in most of studies. The importance of protective eyewear should be reinforced to our patients in our office and though workplace safety education programs to prevent ocular injuries.

Preoperative Considerations

Afocused history and ophthalmic examination are critical to formulate an effective plan. Also, imaging techniques play an important part in the surgical decision-making to de-

termine IOFB characteristics as shape, size and location. Preoperative systemic antibiotics should be considered.

History and Ophthalmic

Examination

Accurate history-taking with attention to the mechanism of injury and material of possible IOFBs should be obtained. Completed ophthalmic exam should be performed with the exception of applanation tonometry when a globe rupture is evident or suspected.

Imaging Techniques

Although a plain X-ray still remains the first line investigation in many units, a negative result should be interpreted with caution if clinical suspicion is high. Plain films may give a false negative result or inaccurately localise the IOFB in up to 30% of eyes.

Computed tomography (CT) of the orbits without contrast is the best choice in suspected or clinically evident globe rupture and can detect IOFB bigger than 0.6 mm3 with a sensitivity of 100%. When an IOFB is found in CT, attention should be paid to its shape, size, location, and material suspected (e.g. metallic, wood, stone, glass, vegetable matter)

Ultrasound, in experienced hands, may identify 93% of IOFB. But the authors only