Surgical therapy of uveitis

Cryotherapy is a good method of treating chronic uveitis, because it is minimally invasive and there are normally no complications. It has proved possible to reduce the frequency and intensity of inflammatory episodes, so that in many cases systemic drug therapy is superfluous. Stabilization or even regression of secondary conditions such as cystoid macular edema or cataract has been achieved, a phenomenon also observed among the present authors' own patients. In cases which did not respond to cryotherapy or where there were severe vitreous opacities vitrectomy was performed. A total of 207 eyes were followed up, on average for 1 1/2 years. During this time visual acuity remained stable or improved in 76% of those treated by cryotherapy, and in over 86% of those treated by vitrectomy.     

Mammographic and CT findings after breast reconstruction with a rectus abdominis musculocutaneous flap.

This essay illustrates the radiologic appearance of the reconstructed breast and the abdominal wall after breast reconstruction with a transverse rectus abdominis musculocutaneous (TRAM) flap. The findings are based on a retrospective study of 42 mammograms, 17 abdominal CT scans, and two CT scans each of the chest and pelvis of patients who underwent this procedure.     

Retinal changes in cystinosis

Cystinosis is a rare autosomal recessive hereditary enzymopathy which leads to accumulation of cystine in the reticuloendothelial system of the liver, spleen, lymph nodes, etc. The pathognomonic alterations of the cornea are characterized by multiple crystalline deposits, chiefly in the limbus area and in the anterior corneal stroma. The retinal changes are seldom described in the literature; they are characterized by a fine-grained pigment shift which intensifies from the macula toward the preequator area and which gives the fundus a 'salt and pepper' appearance.     

Torque-velocity relationships of the knee extensor and flexor muscles in individuals sustaining injuries of the anterior cruciate ligament

Muscle deficits in 58 patients with chronic anterior cruciate ligament (ACL) insufficiency were evaluated after completion of a 6 month rehabilitation program. Quadriceps and hamstring torques were measured on a modified Cybex II isokinetic dynamometer. Twenty-nine of our patients were tested just prior to undergoing ACL reconstruction, and patients who were continuing to tolerate their conditions served as controls. For the surgical group, significant quadriceps deficits (P less than 0.01) were found for all speeds and at both the 30 and 60 degrees positions. The nonsurgical group had significant deficits at the 30 degrees position at 180 degrees/sec, and at 60 degrees for the 0 degree/sec and 30 degrees/sec. However, in comparing the two groups no significant differences were noted. Regarding hamstring deficits in the surgical group, significant deficits were seen only at 30 degrees of flexion at 180 degrees/sec. The nonsurgical group had similar deficits. Of interest was the observation that the hamstring:quadriceps (H:Q) ratio was found to be both speed-position dependent. Overall, no correlation was found between the presence of strength deficits following a rehabilitation program and the need for surgery.     

Strain difference in rat renal microsomal epoxide hydrolase elevation after mercuric chloride treatment

Administration of the nephrotoxicant mercuric chloride (HgCl₂was found to increase microsomal epoxide hydrolase (EH) activityin the kidneys of Fischer 344 (F344) and Sprague-Dawley (SD)rats, but the increases observed were 2- to 4-fold greater inSD rats than in F344 rats. This study was designed to characterizeHgCl₂-mediated increases in renal EH activity, and to investigatepossible biochemical mechanisms underlying the strain difference.In male SD rats killed 24 h after the last of three daily i.p.injections of HgCl₂ (0.1–1 mg/kg), increases in renalEH activity were dose dependent, reaching a maximum of 550%of control. Renal EH activities in identically treated F344rats were enhanced only to 200% of control values, however,the extent of nephrotoxicity was similar in both strains. Followinga single HgCl₂ treatment (1 mg/kg), maximal increases in renalEH activities were observed in SD rats (450% of control) at3 days, and in F344 rats (225%) at 1–2 days. Hepatic glutathione(GSH) concentrations were unaffected by HgCl₂ treatment, whereasrenal GSH was slightly elevated in both strains. Hepatic metallothionein(MT) concentrations were increased at 1 day to 300% and 400%of control in F344 and SD rats, respectively. Maximal renalMT concentrations were observed at 2 and 3 days in F344 (300%of control) and SD (225%) rats, respectively. Pretreatment withZn(OAc)₂, a potent inducer of renal and hepatic MT, reducedthe nephrotoxicity of HgCl₂, but did not alter HgCl₂-mediatedrenal EH increases in either strain. In addition, possible straindifferences in ²⁰³HgCl₂ distribution were assessed, but ²⁰³Hgdistribution was similar in both strains. These studies havedemonstrated that renal EH activity is induced by HgCl₂, andthat there is a strain difference in this response. Differencesin MT, GSH and organ distribution of Hg do not account for thestrain difference. The possibility remains that other, yet tobe defined, protection pathways may exist. Alternatively, renalEH may be differentially regulated between the two strains.