Changes in choroidal area following trabeculectomy: Long-term effect of intraocular pressure reduction.

PURPOSE: To evaluate changes in the macula and peripapillary choroidal area at one year after trabeculectomy in order to determine the effect of intraocular pressure (IOP) changes. METHODS: This prospective longitudinal study examined 30 eyes of 30 patients with glaucoma that was uncontrolled by medical therapy. At 1 day before and at 1 year after the trabeculectomy surgery, macular and peripapillary choroidal images were recorded by enhanced depth imaging optical coherence tomography (EDI-OCT). Luminal and interstitial areas were converted to binary images using the Niblack method. Factors influencing the macular choroidal and peripapillary area were examined by multivariate analysis. RESULTS: After trabeculectomy, the mean IOP was 10.8±3.2 mmHg compared to 17.8±7.2 mmHg at baseline (P < 0.001). The total macular choroidal area after the surgery increased from 317,735±77,380 to 338,120±90,700 µm2, while the interstitial area increased from 108,598±24,502 to 119,172±31,495 µm2 (all P < 0.05). The total peripapillary choroidal area after the surgery also increased from 1,557,487±431,798 to 1,650,253±466,672 µm2, while the interstitial area increased from 689,891±149,476 to 751,816±162,457 µm2 (all P < 0.05). However, there were no significant differences observed in the luminal area before and after the surgery. A decrease in the IOP was among the factors associated with the changes in the peripapillary choroidal area. CONCLUSIONS: IOP reductions after trabeculectomy led to increases in the macular and peripapillary choroidal areas for at least 1 year postoperative. Increases in the interstitial areas were the primary reason for observed changes in the choroidal area after trabeculectomy.

Changes in choroidal area after intraocular pressure reduction following trabeculectomy.

PURPOSE: To investigate changes of the macular and peripapillary choroidal areas after trabeculectomy. METHODS: This prospective and interventional study examined 74 eyes of 74 patients with glaucoma uncontrolled by medical therapy. Enhanced depth imaging optical coherence tomography (EDI-OCT) recorded macular and peripapillary choroidal images at 1 day before trabeculectomy and at 2 weeks after surgery. The Niblack method was used to covert luminal and interstitial areas to binary images. RESULTS: At baseline, the mean intraocular pressure (IOP) was 17.6±6.3 mmHg, while it was 6.5±2.9 mmHg after trabeculectomy (P < 0.001). Increases were observed for the macular choroidal area after the surgery, with the total area increasing from 317,853±95,728 µm2 to 368,597±104,393 µm2, while the luminal area increased from 210,355±73,650 µm2 to 249,464±77,195 µm2, and the interstitial area increased from 107,498±27,613 µm2 to 119,133±31,811 µm2 (all P < 0.001). Increases were also observed after the surgery for the peripapillary choroidal area, with the total area increasing from 1,629,440±460,429 µm2 to 1,974,289±500,496 µm2, while the luminal area increased from 920,141±328,690 µm2 to 1,179,843±357,601 µm2, and the interstitial area increased from 709,299±153,179 µm2 to 794,446±169,029 µm2 (all P < 0.001). There was a significant increase in the ratio of the luminal to choroidal area in the macular area (67.2%) and in the peripapillary area (59.1%). Factors associated with the changes in the peripapillary choroidal area included decreases in the diastolic blood pressure and IOP. CONCLUSIONS: A reduction in the IOP after trabeculectomy led to increases in the macular and peripapillary choroidal areas. Observed changes in the choroidal area after trabeculectomy are primarily due to increases in the luminal areas.

Necrotizing suppurative nephritis in a Japanese black feedlot steer due to Proteus mirabilis infection.

A Japanese black feedlot steer suddenly died after exhibiting astasia and cramping of the extremities. Necropsy of the animal revealed that the right kidney was enlarged and pale with severe nephrolithiasis. The urinary bladder displayed mucosal hemorrhage. Upon bacteriological investigation, Proteus mirabilis was isolated from the liver, spleen, right kidney, lungs and urine. Histopathological examination revealed necrotizing suppurative nephritis with the presence of numerous gram-negative bacilli and fibrinous suppurative cystitis with no bacilli. Immunohistochemical analysis revealed that the bacteria and cytoplasm of the macrophages stained positively with P. mirabilis antiserum. Electron microscopy revealed the presence of numerous bacteria in the renal tubules. To our knowledge, this is the first report describing the histopathological aspects of nephritis caused by P. mirabilis in cattle.