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Understanding the neuropathology of retinal detachment from postmortem and animal models allows identification of cellular targets, receptors and mediators for pharmacological manipulation. In this review, concepts of retinal detachment and neuropathology are examined at cellular and structural anatomical levels using postmortem and animal model data. Possible neuroprotective strategies are reviewed in the setting of the new environment created by successful retinal reattachment surgery.

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Simultaneous recordings of membrane potential and force, and cytoplasmic calcium ([Ca2+]i) and force were made in rat anococcygeus to determine whether membrane hyperpolarisation plays a role in cyclic nucleotide-induced relaxation. In the presence of phenylephrine (0.2 microM), which evoked sustained contraction, an elevation in [Ca2+]i, and depolarisation, nitroprusside (5 microM) caused 96+/-3% relaxation, 77+/-3% decrease in suprabasal [Ca2+]i, and 16+/-2 mV hyperpolarisation. Forskolin (1 microM) caused 98+/-1% relaxation, 92+/-2% decrease in suprabasal [Ca2+]i, and 18+/-1 mV hyperpolarisation. These responses persisted in the presence of a variety of K+ channel blockers or in ouabain. The decrease in [Ca2+]i preceded the commencement of relaxation whereas the onset of hyperpolarisation lagged behind. Thus, cyclic nucleotide-mediated relaxation in rat anococcygeus is not dependent on hyperpolarisation mediated by the opening of K+ channels. Rather, it is suggested that the decrease in [Ca2+]i gives rise to hyperpolarisation, which reflects a decline in the Ca2+ dependent conductance(s) activated by phenylephrine.

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1. Simultaneous recordings of tension and [Ca2+]i were made in rat anococcygeus muscle strips to investigate possible mechanisms involved during cyclic nucleotide-mediated relaxation. Relaxation of pre-contracted muscles was induced by sodium nitroprusside (SNP) or forskolin and the effects of cyclopiazonic acid (CPA) on these responses were examined. 2. In muscles pre-contracted with 0.2 microM phenylephrine addition of SNP (10 microM) caused a rapid and near complete relaxation of force. This was accompanied by a decrease in [Ca2+]i, however, this was not of a comparable magnitude to the decrease in force. The level of [Ca2+]i in muscles relaxed with SNP was shown to be associated with substantially higher force levels in the absence of SNP. Forskolin (10 microM) caused a slower, essentially complete relaxation which was associated with a proportional decrease in [Ca2+]i. 3. In muscles pretreated with SNP or forskolin subsequent responses to phenylephrine were attenuated with both force and [Ca2+]i rising slowly to attain eventually levels similar to those observed when the relaxant was applied to pre-contracted muscles. 4. Exposure of the muscles to the sarcoplasmic reticulum Ca(2+)-ATPase inhibitor, CPA (10 microM), resulted in a sustained increase in [Ca2+]i which, in most cases, was not associated with any force development. The relaxation and decrease in [Ca2+]i in response to both SNP and forskolin were attenuated and substantially slowed in the presence of CPA. Overall the extent of this attenuation was greater for SNP. For both SNP and forskolin, CPA attenuated the decrease in [Ca2+]i to a greater extent than the decrease in force. In some cases, SNP-mediated relaxation in the presence of CPA was observed with almost no detectable change in [Ca2+]i. 5. The results suggest that, in the rat anococcygeus muscle under normal circumstances, a lowering of [Ca2+]i can fully account for the relaxation induced by forskolin but not for that induced by SNP, where mechanisms independent of changes in [Ca2+]i appear to contribute. Whilst Ca2+ sequestration into the sarcoplasmic reticulum plays a role in the relaxation mediated by both SNP and forskolin other Ca2+ lowering mechanisms may also be involved, especially in the response to forskolin.

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1. Simultaneous recordings of tension and [Ca2+]i during NANC-mediated relaxation were made in the rat anococcygeus muscle under various conditions. 2. In muscles precontracted with guanethidine, nitrergic stimulations at 2 Hz produced a rapid decrease in both the tension and [Ca2+]i. 3. The nitric oxide synthase inhibitor, NG-nitro-L-Arginine (NOLA, 100 mumol/L) completely abolished the decreases in the [Ca2+]i and force response of the NANC-mediated relaxation. 4. Noradrenergic-mediated contractions elicited by electrical field stimulation were potentiated by the addition of NOLA. In the absence of NOLA, the motor responses were larger in magnitude at 10 Hz stimulation than at 2 Hz. After NOLA, both the force response and the associated rise in [Ca2+]i were substantially increased in comparison to the control stimulations. Proportionately the potentiation of the 2 Hz response was of a far greater magnitude than that of the 10 Hz response. 5. The guanylate cyclase inhibitor methylene blue (10 mumol/L), partially inhibited the force and [Ca2+]i response of the NANC relaxation. 6. Following exposure of the muscles to the sarcoplasmic reticulum Ca(2+)-ATPase inhibitor, cyclopiazonic acid, (10 mumol/L) the responses to NANC stimulation were inhibited. The attenuated relaxation response displayed a bi-phasic timecourse and the Ca2+ change in comparison to that of the control was markedly smaller. In some cases, a relaxation was observed with no detectable change in the [Ca2+]i. 7. The results suggest that part of the relaxation response observed with NANC-mediated relaxation in the rat anococcygeus is dependent on Ca2+ sequestration into the sarcoplasmic reticulum. However, other Ca2+ lowering mechanisms and possible Ca2+ independent mechanisms may also contribute to the NANC relaxation response.

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Seventy-six patients undergoing combined peribulbar and direct intraconal infiltration local anesthesia for vitreoretinal surgery were prospectively evaluated. Forty-six patients had local anesthesia with a combination of lidocaine 2% and bupivacaine 0.5%; in 30 patients, a combination of lidocaine 2% and prilocaine 1% was used. Patient evaluation of discomfort during the administration of the anesthetic and during the operation was assessed on a visual analog scale of 0 to 10. The mean pain score recorded was 2.73. There was no statistically significant difference between the mean pain scores of the two local anesthetic groups (P = .465).

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A simple technique is described for the transcleral drainage of subretinal fluid during retinal detachment repair. In a prospective study of 94 consecutive suture needle drainage procedures subretinal fluid was successfully drained in 91 cases. There were six 'significant' subretinal haemorrhages associated with the procedure, but none was subfoveal in location or directly compromised the surgical outcome. In no case was retinal incarceration or retinotomy observed.

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Spasm of the near reflex most often has a functional basis, but may be associated with organic disease. This case report describes a patient with a progressive 11-year history of spasm of the near reflex associated with cerebrovascular accidents and reviews the differential diagnosis, management and aetiology of this disease.

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The American health care delivery system has traditionally emphasized the treatment of illness instead of the promotion of wellness. Traditional Health Maintenance Organizations (HMOs) have attempted to reduce costs by controlling utilization, discounting and/or sharing risk with providers rather than promoting wellness and prevention. These efforts have, for the most part, been unsuccessful and health care costs and HMO premiums continue to rise. The authors propose it is time for a change and we must look again at what wellness programs can accomplish. It is time to move from an ineffective "health maintenance" approach towards one of "health achievement." Models for the proposed change already exist in the business community where companies have successfully used wellness programs as a tool to decrease health benefits expenditures. The changes proposed must be addressed on multiple levels. Perceptions, attitudes and approaches must be changed. The benefits of wellness must be individually marketed to target groups: blue and white collar workers, business executives and professionals, home makers, preschool and school age children, the elderly and the unemployable.

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A survey of the extent and type of physical therapy provided to infants less than three months of age was carried out by means of a questionnaire sent to 208 administrators of physical therapy departments in medical school-affiliated hospitals across the United States. Of the 142 administrators who responded, 58.5 percent did not treat or evaluate infants under three months of age. Those treating infants under three months of age used a wide variety of treatments and evaluative forms. The types of treatments and evaluations used are presented.

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