Independent sector treatment centres (ISTCS): early experience from an ophthalmology perspective.

In 2001, the NHS plan concluded that there was a significant lack of capacity within current NHS structures to deliver adequate volumes of cataract surgery for England and Wales. The initial central 'solution' for this was to invite in overseas surgical teams to existing NHS centres for short-term surgical initiatives. However, with the advent of the Waiting, Booking and Choice Strategy, a target was set for treatment centers (TCs) to be carrying out an additional 250 000 inpatient/day-case episodes, across all specialties, by 2005. This paper outlines how these Ophthalmology TCs were commissioned, and some of the policy and medical agendas that surrounded their evolution. The concept of 'take or pay' contracts, which placed the onus on local Primary Care Trust organisations to provide the promised number of suitable cataract patients for the TCs, and the 'additionality' of medical and nursing staff are discussed. In September 2003, Netcare was awarded the contract to carry out 41 600 cataract procedures over a 5-year period in a mixture of mobile and fixed site units. Netcare's proposed patient care pathways are examined, as is the reality of its interaction with local Ophthalmology Departments and the response of the Royal College of Ophthalmologists to its standards of patient care. Although Netcare TCs may have contributed to reduced waiting times for cataract surgery in some districts, the quality of care provided by the Netcare TCs has yet to be established. There are ongoing concerns about both the continuity of care and the management of postoperative complications, as well as the economics of neighbouring NHS units.

Rectus muscle trauma complicating sub-Tenon's local anaesthesia.

PURPOSE: To describe three cases of rectus muscle trauma in patients undergoing phacoemulsification cataract extraction and intraocular lens implantation under sub-Tenon's local anaesthesia via the inferonasal quadrant. METHODS: Retrospective review was carried out of 3 cases from 1080 patients who underwent phacoemulsification cataract extraction and intraocular lens implantation under sub-Tenon's local anaesthesia in our unit over a 3 year period up to April 2000. RESULTS: Two patients complained postoperatively of vertical diplopia and were shown to have restriction of elevation of the eye, which was found at surgical exploration to be due to inferior rectus muscle restriction. One patient had post-operative horizontal diplopia due restriction of abduction and exploration of the medial rectus muscle was planned. CONCLUSION: Rectus muscle trauma is proposed as a complication of sub-Tenon's local anaesthesia and caution is advised to operators to clearly identify the sub-Tenon's space for injection of local anaesthetic.

Pathogenesis of idiopathic macular holes.

An improvement in our understanding of the pathogenesis and natural history of idiopathic macular holes over the last 10 years has led to a more optimistic and interventionist approach to the surgical management of this vitreoretinal disorder. This article reviews the theories postulated for the pathogenesis of this condition and looks at recent work that has investigated the role of the vitreous, internal limiting membrane, and posterior vitreous detachment in the natural history of macular holes.

Screening for cytomegalovirus retinitis in HIV-positive and AIDS patients.

The ability of physicians to screen for AIDS-related cytomegalovirus retinitis (CMVR) was studied at a London AIDS centre. Patients had undergone direct ophthalmoscopy as part of their general examination by the physicians and were referred if fundal abnormalities were found, if a focus of extra-ocular CMVR was present or if the patient complained of visual symptoms. The provisional diagnoses of the physicians were compared with the final diagnoses of the ophthalmologists. Of 348 consecutive patients referred for an ophthalmic opinion, the physicians made the correct diagnosis in 69% of those referred with a provisional diagnosis of CMVR, in 66% of those with normal fundi and in 81% of those with toxoplasma chorioretinitis. Those cases of CMVR which were misdiagnosed by the physicians were usually mistaken for other retinal pathology which would warrant a specialist referral. Screening for CMVR in HIV-positive and AIDS patients may safely be undertaken by physicians familiar with the ocular manifestations of HIV-related disease.

Retinal detachment in AIDS-related cytomegalovirus retinitis.

Patients with acquired immune deficiency syndrome (AIDS) and cytomegalovirus retinitis (CMVR) are surviving longer due to the use of virostatic medicines and improved treatment of opportunistic infections. As a result, retinal detachment is likely to become an increasingly common cause of visual morbidity in these patients. The incidence and outcome of retinal detachment complicating CMVR was studied at two London AIDS centres. Patients with CMVR were identified prospectively and underwent standard treatment. Retinal detachments were diagnosed during regular follow-up. If retinal reattachment surgery was performed, a standard procedure of vitrectomy and silicone oil internal tamponade was employed. Of 147 patients with CMVR, 41 (28%) developed retinal detachments (47 eyes). Forty-three detachments were rhegmatogenous and 4 were exudative. Fifteen eyes of 9 patients with rhegmatogenous detachments underwent retinal reattachment surgery. Of these, visual acuity remained stable or improved in 12 eyes (80%) in the immediate post-operative period. At the last clinic visit, 8 eyes (53%) maintained a visual acuity of 6/60 or better. The visual results of surgery are good in selected patients, bearing in mind the progressive nature of the underlying disease and poor life expectancy.

Quantification of melanin and iron content in uveal malignant melanomas and correlation with magnetic resonance image.

Eleven patients with uveal malignant melanomas (MM) were studied by magnetic resonance (MR) imaging before enucleation. The MR appearances varied, but often were different from those previously reported to be characteristic of these tumours. Using an image analyser to assess quantitatively the melanin and iron content of each tumour, a wide range of tumour melanin concentrations was found, but universally low tumour iron concentrations. These values were compared with MR appearances that were quantified and expressed as contrast to noise ratios. The correlation between T1 and T2 shortening and increasing melanin content did not reach statistical significance. There was no correlation between MR appearances and iron content. The theories postulated to explain the diverse MR appearances of uveal MMs are discussed and variations in tumour melanin content and differences in scanner strengths are suggested as the most likely explanations.

Appearances of choroidal osteomas with diagnostic imaging.

The diagnostic imaging appearances of three choroidal osteomas (osseous choristomas) are presented. This rare, benign choroidal tumour is being recognized with increasing frequency, and is important to remember in the differential diagnosis of any unusual mass in the ocular fundus lest it be mistaken for a more sinister lesion. All three osteomas were demonstrated by ocular ultrasound (US), fluorescein angiography (FA) and computed tomography (CT) but none by plain radiography. None of the lesions was visible on magnetic resonance imaging (MRI); the reason for this is probably the bony nature of the tumours. The appearances of choroidal osteomas on US, FA, plain radiography and CT are discussed. To our knowledge this is the first report of a series of choroidal osteomas investigated by MR.

Magnetic resonance imaging. Diverse appearances of uveal malignant melanomas.

Fifteen patients with uveal malignant melanomas were studied by magnetic resonance imaging. The magnetic resonance imaging appearances varied from those that have been reported previously to be characteristic of these tumors. In our series, malignant melanomas were of high signal on the T1 sequence and of variable but usually also of high signal on the T2 and Short Tau Inversion Recovery (STIR) sequences, a signal combination rarely described before. We postulate that magnetic resonance imaging appearances may be dependent on variations in histologic factors and on the type and field strength of the scanner used. It is widely believed that the paramagnetic melanin in malignant melanomas gives these tumors characteristic magnetic resonance imaging appearances, but our finding of diverse magnetic resonance imaging appearances for proved malignant melanomas suggests that this may not always be the case. We advise caution in diagnosing malignant melanomas from magnetic resonance imaging appearances alone.