Influence of optic disc size on neuroretinal rim shape in healthy eyes.

PURPOSE: To evaluate the influence of optic disc size on segmental neuroretinal rim area in healthy eyes. PATIENTS AND METHODS: The study included 193 eyes of 193 healthy patients with physiologic disc cupping. On 15 degrees color stereophotographic optic disc diapositives, optic disc area and neuroretinal rim area were morphometrically determined in 36 radial optic disc segments each measuring 10 degrees. RESULTS: The correlations of segmental rim area to disc area were significantly strongest (P < 0.01) and the regression lines were steepest in the inferior disc region, and the values were lowest in the temporal disc region. Complementary to the rim data, the correlations of segmental cup area to disc area were significantly strongest (P < 0.01) and the regression lines were steepest in the temporal disc region, and the values were lowest in the inferior disc region. In comparison with neuroretinal rim area, cup area was significantly (P < 0.01) more strongly correlated with disc area and the regression line was steeper in the whole optic disc and in each disc segment. The regional distribution of the widest rim part and smallest rim part was independent of disc size. CONCLUSIONS: The increase of rim area and cup area with increasing disc size differs between various disc regions. Because cup area increases more than rim area with increasing disc size, correction for disc size may be more important for segmental cup area than for segmental rim area. The rim shape with respect to the location of the smallest or broadest rim part is independent of disc size.

Indwelling temporary retrobulbar catheter for long-lasting titratable local anesthesia.

OBJECTIVE: To evaluate an indwelling temporary retrobulbar catheter for repeatable injections of local anesthetics for long-lasting and titratable retrobulbar anesthesia in intraocular surgery. PARTICIPANTS: The prospective clinic-based study included 153 patients who underwent vitreoretinal surgery (n=111) or buckling procedures with cryocoagulation (n=34). The mean duration of surgery was 84.7 +/- 49.5 minutes (range, 25-310 minutes). Using commercially available retrobulbar needles with a diameter of 0.60 or 0.80 mm and a length of 38 mm, 5 mL of 2% mepivacaine hydrochloride was injected. Through the same needle, a 28-gauge commercially available flexible catheter was introduced into the retrobulbar space. The needle was withdrawn and the catheter was fixed. When the patients started to feel pain during surgery, 2 mL of mepivacaine hydrochloride was reinjected through the catheter. RESULTS: Ten to 240 minutes after the start of the operation, 96 patients needed an intraoperative reinjection of mepivacaine after which they felt comfortable again. Forty-two patients needed a second reinjection of mepivacaine 30 to 270 minutes after the start of the operation, and 13 patients needed a third reinjection 45 to 145 minutes after the start of surgery. Removal of the catheter after surgery was unremarkable. No infections were observed. Microbiologic examination results of the catheter tip were negative for organisms. Diplopia or other motility problems were not detected. Introduction and fixation of the catheter took less than 5 minutes in all patients. CONCLUSIONS: An indwelling temporary retrobulbar catheter for repeatable intraoperative injections of local anesthetics is simple, effective, and useful, and in comparison with general anesthesia, it is a time-saver for long-lasting and titratable local anesthesia in intraocular surgery. Arch Ophthalmol. 2000;118:996-1000

Optic nerve head appearance in juvenile-onset chronic high-pressure glaucoma and normal-pressure glaucoma.

OBJECTIVE: To evaluate the appearance of the optic nerve head in chronic high-pressure glaucoma and normal-pressure glaucoma. DESIGN: Clinic-based cross-sectional study. PARTICIPANTS: The study included 52 eyes with normal-pressure glaucoma and 28 eyes with juvenile-onset primary open-angle glaucoma that served as models for chronic high-pressure glaucoma. METHODS: Color stereo optic disc photographs and wide-angle retinal nerve fiber layer photographs were morphometrically examined. MAIN OUTCOME MEASURES: Localized retinal nerve fiber layer defects; parapapillary chorioretinal atrophy; disc hemorrhages; optic cup shape; retinal arteriole narrowing. RESULTS: Both study groups did not vary significantly in count of localized retinal nerve fiber layer defects, size of parapapillary atrophy, optic cup depth, steepness of disc cupping, rim/disc area ratio, diameter of retinal arterioles, and frequency and degree of focal retinal arteriole narrowing. In normal-pressure glaucoma versus juvenile open-angle glaucoma, localized retinal nerve fiber layer defects were significantly broader, disc hemorrhages were found significantly more often and were larger, and neuroretinal rim notches were present more frequently and were deeper. CONCLUSIONS: Chronic high-pressure glaucoma and normal-pressure glaucoma show morphologic similarities in the appearance of the optic nerve head. The lower frequencies of detected disc hemorrhages and rim notches in high-pressure glaucoma may be due to a smaller size of hemorrhages and localized retinal nerve fiber layer defects in high-pressure glaucoma. Both glaucoma types have morphologic features in common, suggesting that they may possibly belong to a spectrum of the same pathologic process.

Postoperative analgesia by reinjections of local anesthetic through an indwelling retrobulbar catheter.

PURPOSE: To evaluate an indwelling retrobulbar catheter for repeatable postoperative retrobulbar injections of local anesthetics for titratable analgesia after intraocular surgery. METHODS: The prospective study included all 124 patients (124 eyes) who consecutively underwent retinal or cyclocryocoagulation (n = 22), pars plana vitrectomy, or retinal detachment surgery (n = 102), and who were operated on by the same surgeon with local anesthesia within a period of 12 months. Using commercially available retrobulbar needles with a diameter of 0.60 mm or 0.80 mm and a length of 38 mm, 5 ml of mepivacaine 2% with hyaluronidase were injected. Through the same needle, a 28-gauge commercially available flexible catheter was introduced into the retrobulbar space, the needle was withdrawn, and the catheter was fixed in place. When the patients started to feel pain after surgery, 2 ml of mepivacaine 2% or 2 ml of bupivacaine 0.75% were reinjected through the catheter. The catheter was removed 24 to 72 hours after surgery. RESULTS: Because of increasing pain in the postoperative period, 93 patients (93 of 124, or 75%) received a reinjection 4.2+/-2.0 hours after the preoperative injection. Seventy patients received a second reinjection after an additional 2.7+/-1.9 hours, and 42 patients received a third reinjection 3.1+/-2.0 hours later. After each reinjection, the patients became pain free. Removal of the catheter after surgery was unremarkable. CONCLUSIONS: An indwelling retrobulbar catheter for repeatable postoperative injection of short-acting local anesthetics is useful and effective for titratable postoperative analgesia after intraocular surgery, and it allows patients to avoid the side effects of systemic analgesics and sedatives.

[Morphology of the optic papilla in glaucoma. I. Primary open-angle glaucoma]. / Die Morphologie der Papille beim Glaukom. I. Primäre Offenwinkelglaukome.

BACKGROUND: Previous studies have shown that the chronic open-angle glaucomas form a heterogeneous spectrum of diseases which have in common an open anterior chamber angle and glaucomatous optic nerve damage. Purpose of this study was to evaluate whether the appearance of the optic disc differs among the various types of primary open-angle glaucoma. METHODS: Color stereo optic disc photographs of 683 patients with primary open-angle glaucoma (POAG), and 481 normal eyes were morphometrically evaluated. RESULTS: Morphologic characteristics of the glaucoma types were as follows: Highly myopic POAG: secondary macrodiscs with abnormal shape; shallow, flat, concentric disc cupping; low frequency of disc hemorrhages; large parapapillary atrophy or myopic crescent; medium to low intraocular pressure. Juvenile-onset POAG: Optic disc of normal size and shape; deep and steep disc cupping; low frequency of broad rim notches or large disc hemorrhages; small parapapillary atrophy; high minimal and maximal intraocular pressure measurements. Age-related atrophic POAG: Optic disc of normal size and shape; shallow, flat and concentric disc cupping; medium to low frequency of disc hemorrhages; large parapapillary atrophy; medium to low intraocular pressure. Eyes with normal-pressure glaucoma: Optic disc of normal size and shape; deep and steep cupping; relatively small parapapillary atrophy; high frequency of disc hemorrhages and rim notches. CONCLUSIONS: These characteristics in the appearance of the optic disc may be helpful for clinical diagnosis and therapy and may give pathogenetic hints.

[Titration of intraoperative anesthesia and postoperative analgesia]. / Titrierbare intraoperative Anästhesie und postoperative Analgesie.

PURPOSE: To evaluate a temporary retrobulbar catheter for local anesthesia in intraocular surgery and for postoperative analgesia after intraocular surgery. PATIENTS AND METHODS: The study included 40 patients undergoing pars-plana vitrectomy (n = 24) or cyclocryocoagulation (n = 16). After a retrobulbar injection through a 23 G needle, a commercially available 28 G flexible catheter was inserted through the needle. As soon as the patients complained about pain during or up to 24 hours after surgery, local anesthetics were injected through the catheter. RESULTS: Repetitive injections of anesthetics were necessary in 13 patients during pars plana vitrectomy. Starting about 2 hours after surgery, 13 patients after pars-plana vitrectomy and all patients who had undergone cyclocryocoagulation received up to 6 re-injections (every 1.5-5 hours). After all re-injections, the patients became pain-free within two minutes. The catheter was removed after 24 hours. CONCLUSIONS: The results suggest that a temporary insertion of a catheter into the retrobulbar space allows repetitive application of local anesthetics thus leading to a titrable local anesthesia and postoperative analgesia in intraocular surgery.