Acrophase amplitude of ambulatory blood pressure decreases in migraineurs

Ambulatory blood pressure was recorded and analyzed in 13 migraineurs during headache-free periods and in 11 healthy subjects. Systolic blood pressure, mean blood pressure, diastolic blood pressure, pulse pressure, and pulse rate were recorded for 48 hours (three times every hour from 6 AM to mid-night, once an hour at night). Circadian variation of blood pressure was analyzed using single cosinor analysis and group mean cosinor analysis methods. Single cosinor analysis identified significant circadian rhythm of systolic blood pressure in 10 of 11 control subjects (90.9%) and 5 of 13 migraineurs (38.5%, P < 0.02 versus controls, Fisher's exact test). Incidences of significant circadian rhythm of mean blood pressure and diastolic blood pressure were 100% and 100% in controls, 46.2% and 53.8% in the migraineurs (P < 0.01, P < 0.02 versus controls). Incidences of significant rhythm of pulse pressure were 36.3% in controls and 38.5% in the migraine group (difference was not significant). Group mean cosinor analysis identified significant circadian rhythm in both the migraine group and the controls. The MESOR (midline estimating statistic of rhythm) values of systolic, mean, and diastolic blood pressures showed no significant differences between the migraine group and the controls. Acrophase amplitudes of systolic, mean, and diastolic blood pressure were 4.2, 5.2, and 5.9 mm Hg in the migraine group, respectively; and 7.2, 7.3, and 7.5 mm Hg in the controls, respectively. These amplitudes of systolic, mean, and diastolic blood pressures in the migraine group were significantly smaller than those in the controls. These data suggest that some migraineurs lose or alter their circadian blood pressure rhythm. Evaluating migraineurs as a group, significant circadian rhythm of blood pressure can be identified and oscillation amplitudes of blood pressures are decreased. The present results suggest that migraineurs may be subject to dysfunction of the circadian rhythm generator and the autonomic nervous system. Possible involvement of serotonergic projections from the raphe to the suprachiasmatic nuclei of the hypothalamus in migraine is discussed.     

Risk factors for unsatisfactory intraocular pressure control in combined trabeculectomy and cataract surgery

Fine-needle aspirates and tissue sections from 120 surgically treated parathyroid (PT) lesions and histologic archive material from PT lesions in 1,500 additional cases of hyperparathyroidism were reviewed to assess the importance of various features in distinguishing PT disease from other types of lesions by aspiration cytology. We conclude that the morphologic variation shown by PT lesions is so many-sided that this distinction cannot be based on the presence or absence of a single feature only. Instead the cytologic picture as a whole must be taken into account and evaluated with full knowledge of the anatomical conditions pertaining to the lesion examined. If still in doubt, the diagnosis can be substantiated by supplementary immunocytochemical examinations.     

Effects of changes in intraocular pressure on human ocular haemodynamics

PURPOSE: Myogenic autoregulation is the ability of a vascular bed to maintain blood flow despite changes in perfusion pressure. Ocular perfusion pressure is defined as the difference between ocular arterial pressure and ocular venous pressure, the latter dependent on intraocular pressure (IOP). The aim of the present study was to investigate the effect of moderate increases in IOP on ocular haemodynamics. METHODS: Changes in IOP (+ 10 mmHg, +20 mmHg) were induced by a suction cup in 10 healthy subjects. Ocular fundus pulsations in the macula and the optic disc were measured by laser interferometry; blood flow velocities in the central retinal artery (CRA) and in the ophthalmic artery (OA) were measured by Doppler sonography. RESULTS: Changes in IOP caused a significant reduction in fundus pulsations, which was more pronounced in the macula (at +10 mmHg: -9 +/- 2%, p < 0.01; at +20 mmHg: -19 +/- 3%, p < 0.001) than in the optic disc (at +10 mmHg: -5 +/- 2% (ns); at +20 mmHg: -9 +/- 3%, p < 0.01). Mean flow velocity in the CRA was reduced by -5 +/- 3% at +10 mmHg (ns) and by -14 +/- 5% at +20 mmHg (p < 0.005), resistive index was increased by +4 +/- 1% at +10 mmHg (p < 0.05) and by +6 +/- 2% at +20 mmHg (p < 0.01). In contrast, a rise in IOP did not affect blood flow parameters in the OA. CONCLUSIONS: Our results from fundus pulsation measurements indicate that choroidal blood flow decreases when IOP is increased. The Doppler sonographic findings in the CRA indicate reduced blood flow velocity in this artery during raised IOP.     

Effect of intravenous fenoldopam on intraocular pressure in ocular hypertension

Intravenous fenoldopam, a selective dopamine-1 receptor agonist, was compared with placebo in this randomized, double-blind, two-period crossover study to evaluate its effects on intraocular pressure, aqueous dynamics, and macular blood flow in patients with elevated intraocular pressure or primary open-angle glaucoma. Doses of fenoldopam were titrated up to a maximum of 0.5 microgram/kg/min. Intraocular pressure, measured by pneumotonometry, was the primary outcome variable. Other outcomes included macular blood flow assessed by blue field examination, visual field examined by automated perimetry, aqueous outflow facility measured by tonography, and aqueous humor production determined by fluorophotometry. During infusions of fenoldopam, intraocular pressure increased from a mean baseline level of 29.2 mmHg to a mean maximum level of 35.7 mmHg. During the placebo infusions, pressure increased from a mean baseline of 28.4 mmHg to a mean of 29.0 mmHg at the time point that corresponded to the mean maximum intraocular pressure on the day intravenous fenoldopam was administered, to yield a mean difference in pressure between study days of 6.7 mmHg (P < 0.05). There were no apparent changes in macular blood flow, visual fields, or production or outflow of aqueous humor associated with fenoldopam infusion. The increase in intraocular pressure seen in this population of patients with ocular hypertension during infusions of fenoldopam is consistent with fenoldopam-associated increases in intraocular pressure reported in previous studies of healthy volunteers and of patients with accelerated systemic hypertension. These results further suggest that dopamine-1 receptors play a role in the regulation of intraocular pressure.     

Tracheal pressure triggering a demand-flow continuous positive airway pressure system decreases patient work of breathing

OBJECTIVES: Triggering a ventilator "ON" at the carinal end of the endotracheal tube decreases imposed work of breathing by bypassing the resistance imposed by the breathing circuit and the endotracheal tube. We compared work of breathing during spontaneous ventilation between three methods of triggering the ventilator "ON": a) conventional pressure triggering from inside the ventilator; b) flow-by triggering; or c) tracheal pressure triggering at the carinal end of the endotracheal tube. We hypothesized that the work of breathing would be substantially decreased with tracheal pressure triggering compared with conventional pressure and flow-by methods in patients receiving continuous positive airway pressure. DESIGN: Clinical, prospective study. SETTING: University teaching hospital. PATIENTS: Fourteen adults diagnosed with acute respiratory failure. INTERVENTIONS: All patients were breathing spontaneously at an FIO2 of 0.30 to 0.40 and received 5 cm H2O of continuous positive airway pressure. Three different methods of triggering the ventilator while set in the continuous positive airway pressure mode were administered in random order. MEASUREMENTS AND MAIN RESULTS: Real-time measurements of esophageal pressure and tidal volume were integrated with a respiratory monitor (CP-100, Bicore, Riverside, CA) that uses the Campbell diagram to calculate total work of breathing. Imposed work of breathing was calculated by integrating tidal volume with the pressure at the carinal end of the endotracheal tube. Physiologic work of breathing was calculated by subtracting imposed work of breathing from the total work of breathing. Breathing frequency, the index of rapid shallow breathing (breathing frequency/tidal volume), peak inspiratory flow rate demand, exhaled minute ventilation, and the duration of respiratory muscle contraction assessed by the ratio of inspiratory time to total cycle time were also measured. Data were analyzed by Friedman's repeated-measures analysis of variance on ranks. Alpha was set at .05 for statistical significance. Imposed work of breathing decreased to approximately zero during tracheal pressure triggering. As a result, total work of breathing decreased by approximately 40% compared with the flow-by and conventional methods. During tracheal pressure triggering only, airway pressure increased above baseline pressure to approximately 11 cm H2O, which resembled pressure-support ventilation. Also, during tracheal pressure triggering, tidal volume and peak inspiratory flow rate were significantly increased, while the pressure-time product and the index of rapid shallow breathing were significantly decreased. Hemodynamic status and oxygen saturation were not clinically affected. CONCLUSIONS: The tracheal pressure triggering of a demand-flow continuous positive airway pressure system creates an effect similar to pressure-support ventilation that significantly decreases imposed work of breathing and, thus, total work of breathing. We recommend moving the triggering site of the ventilator to the carinal end of the endotracheal tube.     

Long-term intraocular pressure control after cataract extraction with trabeculectomy: phacoemulsification versus extracapsular technique

Mutations of the p53 gene are associated with a number of non-lymphoid cancers of the dog. The present study investigates the p53 gene status within canine patients treated for primary and secondary lymphoma. Three out of eight patients exhibited p53 gene mutations. These included one patient with a germ line mutation and two patients with de novo p53 mutations associated with the secondary lymphoma. Allelic loss of the p53 gene was also observed within primary and secondary tumours of the three canine patients. The results indicate that germ line p53 mutations exist in dogs and may be involved in the known predisposition of some breeds to cancer. The presence of therapy-related p53 point mutations was found to be associated with chemoresistant secondary lymphomas. A causative role for DNA-damaging chemotherapy in de novo mutation of the p53 gene is discussed. Characterization of p53 inactivation in canine tumorigenesis may provide a valuable clinical model for assessing the efficacy and optimal therapeutic regimens of anti-cancer agents.     

Femoral and genitofemoral nerve blocks versus spinal anesthesia for outpatients undergoing long saphenous vein stripping surgery

Long saphenous vein stripping (LSVS) surgery is often used to treat varicose veins. We tested the hypothesis that femoral nerve block (FNB) with genitofemoral nerve infiltration provides sufficient analgesia and superior recovery characteristics to spinal anesthesia for LSVS procedures in the ambulatory setting. Thirty-six patients were randomized to receive FNB with 30 mL of 3% alkalinized chloroprocaine, and 32 patients received spinal anesthesia with 65 mg of 5% hyperbaric lidocaine. Data collected included patient demographics, time required for induction of and recovery from anesthesia, postoperative anesthesia complications, and patient report of pain severity after the operation. During a follow-up call, a blinded observer noted the onset of any complications, the requirement for analgesics, and the patients' satisfaction with the anesthetic technique. Patients in the FNB group had significantly faster recovery (P < 0.01) and lower incidences of pain (P < 0.05) and complications (P < 0.05) than the patients in the spinal group. All patients who received FNB indicated that they would choose this type of anesthesia in the future, whereas five (15%) patients in the spinal group would refuse spinal anesthesia in the future (P < 0.01). We conclude that FNB is an excellent anesthetic choice for LSVS.     

The effect of arterial pressure on the ocular pressure-volume relationship in the rabbit

The purpose of this study was to quantify the effect of mean arterial pressure (MAP) on the ocular pressure-volume relationship. The experiments were performed in pentobarbital anesthetized rabbits instrumented with occluders on the thoracic aorta and inferior vena cava to control MAP which was measured via a cannula in the central ear artery. To vary the ocular volume and measure the intraocular pressure (IOP), two 23 gauge needles were inserted through the pars plana into the vitreous: one needle was connected to a saline-filled syringe and the other needle was connected to a pressure transducer. In one group of animals (n = 5), pressure-volume curves were determined at MAPs of 100, 80, 60, 40 and 20 mmHg and post mortem by cumulative saline injections (2 microliters) every 1-1.5 sec. In a second group (n = 7), pressure-volume curves were obtained at MAPs of 80, 60 and 40 mmHg and post mortem by saline infusion at 0.5 microliter sec-1 until the IOP reached 100 mmHg. The infusion protocol was repeated in a third group (n = 11) where the choroidal flux and the concentration of moving blood cells (CMBC) were measured by a laser Doppler flowmeter as indices of choroidal blood flow and the blood volume, respectively. MAP had three primary effects on the ocular pressure-volume relationship: (1) the baseline IOP varied exponentially with MAP, (2) the steepness of the initial portion of the pressure-volume curves was MAP-dependent and (3) the curves exhibited a 'plateau' as the IOP approached the prevailing MAP at MAPs > or = 40 mmHg. All of the curves in the living eye intersected and became indistinguishable from the post mortem curve when the IOP exceeded the prevailing MAP. The flux and CMBC measurements indicated that the MAP-dependence of the initial portion of the curves was due to failure of choroidal autoregulation and diminished increases in choroidal blood volume at the lower MAPs, and that the plateau portion of the curves was due to expulsion of blood from the eye. It is concluded that MAP has a significant effect on the ocular pressure-volume relationship.     

Intravenous injection with antisense oligodeoxynucleotides against angiotensinogen decreases blood pressure in spontaneously hypertensive rats

In the renin-angiotensin system, renin is known to cleave angiotensinogen to generate angiotensin I, which is the precursor of angiotensin II. Angiotensin II is a vasoactive peptide that plays an important role in blood pressure. On the other hand, the liver is the major organ responsible for the production of angiotensinogen in spontaneously hypertensive rats (SHR). To test the hypothesis that a reduction of angiotensinogen mRNA in the liver by antisense oligodeoxynucleotides (ODNs) may affect both plasma angiotensinogen and angiotensin II levels, as well as blood pressure, we intravenously injected antisense ODNs against rat angiotensinogen coupled to asialoglycoprotein carrier molecules, which serve as an important regulator of liver gene expression, into SHR via the tail vein. The SHR used in the present study were studied at 20 weeks of age and were fed a standard diet throughout the experiment. Plasma angiotensinogen, angiotensin II concentrations, and blood pressure all decreased from the next day until up to 5 days after the injection of antisense ODNs. These concentrations thereafter returned to baseline by 7 days after injection. A reduction in the level of hepatic angiotensinogen mRNA was also observed from the day after injection until 5 days after injection with antisense ODNs. However, in the SHR injected with sense ODNs, plasma angiotensinogen, angiotensin II concentrations, and blood pressure, as well as hepatic angiotensinogen mRNA, did not significantly change throughout the experimental period. Although the exact role of angiotensinogen in hypertension still remains to be clarified, these findings showed that intravenous injection with antisense ODNs against angiotensinogen coupled to asialoglycoprotein carrier molecules targeted to the liver could thus inhibit plasma angiotensinogen levels and, as a result, induce a decrease in blood pressure in SHR.     

I1-imidazoline agonist moxonidine decreases sympathetic nerve activity and blood pressure in hypertensives

Moxonidine is an I1-imidazoline receptor agonist that reduces blood pressure in hypertensives. Experimental data suggest that moxonidine inhibits central sympathetic activity. However, whether such a mechanism is involved in vivo in humans is still unclear. We investigated the effects of 0.4 mg moxonidine orally on muscle sympathetic nerve activity and heart rate in an open study in 8 healthy volunteers. Furthermore, we studied the effects of 0.4 mg moxonidine on muscle sympathetic nerve activity, heart rate, blood pressure, 24-hour blood pressure profile, and hormone plasma levels in 25 untreated hypertensives in a double-blind, placebo-controlled study. Moxonidine decreased muscle sympathetic nerve activity in both healthy volunteers (P<0.05 versus baseline) and hypertensives (P<0.02 versus placebo). Plasma norepinephrine also decreased (P<0. 01), whereas plasma epinephrine and renin levels did not change (P=NS). Furthermore, moxonidine decreased systolic (P<0.0001) and diastolic (P<0.001) blood pressure. Heart rate decreased after moxonidine in healthy subjects (P<0.05); in hypertensives, heart rate decreased during the night hours (P<0.05) but not during daytime (P=NS). Plasma levels of LDL, HDL, and total cholesterol were not influenced by the drug (P=NS). Moxonidine decreases systolic and diastolic blood pressure by inhibiting central nervous sympathetic activity. This makes this new drug suitable for the treatment of human hypertension and possibly for other cardiovascular diseases with increased sympathetic nerve activity, ie, ischemic heart disease and heart failure.     

Chronic use of apraclonidine decreases its moderation of post-laser intraocular pressure spikes

OBJECTIVE: The purpose of the study is to investigate the efficacy of 1.0% apraclonidine in preventing intraocular pressure (IOP) spike after argon laser trabeculoplasty (ALT) in patients on chronic apraclonidine therapy compared with patients not on chronic apraclonidine use. DESIGN: The study design was a prospective study. PARTICIPANTS: This study consisted of 231 consecutive eyes of patients with primary open-angle glaucoma undergoing ALT: 70 eyes (30%) were started on a regimen including chronic apraclonidine 0.5% use (group A) and 161 eyes (70%) were started on a regimen without chronic apraclonidine 0.5% use (group B). INTERVENTION: Both groups received one drop of apraclonidine 1.0% 15 minutes before ALT to 180 degrees of previously untreated trabecular meshwork. Intraocular pressure was measured before the procedure and at 5 minutes, 1 hour, and 24 hours after the laser treatment. MAIN OUTCOME MEASURES: Incidences of an IOP spike and mean IOPs at 5 minutes, 1 hour, and 24 hours after the laser treatment were compared between the two groups. Multivariate logistic regression analysis also was carried out to identify the significant risk factors for post-ALT IOP spikes despite prophylactic apraclonidine 1.0% treatment. RESULTS: The incidences of IOP spikes greater than 0 mmHg, greater than 2 mmHg, and greater than 5 mmHg at 1 hour after ALT were 32.9%, 22.9%, and 12.9%, respectively, in group A versus 13.7%, 11%, and 3.1%, respectively, in group B (P = 0.0007, P = 0.009, and P = 0.004). Chronic apraclonidine 0.5% use was found to be the only significant risk factor for IOP spikes at 1 hour after ALT by multivariate logistic regression analysis. CONCLUSIONS: The incidences of IOP spikes in group A were significantly greater than in group B and approached the reported incidences of IOP spikes without perilaser apraclonidine prophylaxis. This indicates that peri-ALT apraclonidine is relatively ineffective in patients with chronic apraclonidine 0.5% use (group A) compared with patients without chronic apraclonidine use (group B), presumably because of saturation of the ocular alpha-2 receptors with apraclonidine in patients with chronic apraclonidine use. Therefore, in patients receiving chronic apraclonidine therapy, it is especially important to monitor their post-ALT IOPs and to be prepared to treat postlaser IOP spikes using agents other than apraclonidine.     

Effect of pilocarpine ocular therapeutic systems on diurnal control of intraocular pressure

The pilocarpine ocular therapeutic system is an innovative ocular drug delivery system which releases pilocarpine into the tear film at a constant rate of 20mug/hr or 40mug/hr. The system was evaluated in 22 hospitalized patients with bilateral open angle glaucoma to determine its ability to control ocular pressure throughout the diurnal interval. Only the right eye of each patient was treated with the pilocarpine ocular therapeutic system; the other eye served as a control. Twelve pressure measurements were made with a noncontacttorometer over a 34-hour test period. In general, the pilocarpine ocular therapeutic system provided satisfactory around-the-clock control of intraocular pressure and was well tolerated by the patients.     

Panic disorder in cardiac outpatients

OBJECTIVE: Continuing the long history of interest in the relation of anxiety disorders to cardiovascular function and symptoms, this study investigated the level of anxiety and prevalence of panic disorder in cardiac patients and the possible associations between specific abnormal ECG results and a diagnosis of panic disorder. METHOD: Consecutive patients referred for ambulatory ECG recordings were assessed with the seven anxiety items of the Hospital Anxiety and Depression Scale. Then, 50 patients with scores higher than 8 (the anxious group) were interviewed with the Schedule for Affective Disorders and Schizophrenia--Lifetime Version Modified for the Study of Anxiety Disorders (SADS-LA). RESULTS: Of the 50 anxious patients (26 male and 24 female) interviewed with the SADS-LA, 62% (N = 31) met the DSM-III-R criteria for panic disorder. Patients with panic disorder had a higher mean maximal heart rate and a shorter P-R interval than patients without panic disorder. Unlike the patients without panic disorder, the patients with panic disorder showed no correlation between maximal heart rate and minimal P-R interval. CONCLUSIONS: The rate of panic disorder was high in the patients referred for ECG. Moreover, the prevalence of panic disorder was similar in the patients with and without ECG abnormalities, indicating that in anxious patients the presence of panic disorder does not rule out organic cardiac disease. On the other hand, the higher maximal heart rate and shorter P-R interval of the panic patients may be attributable to hypersensitivity of beta-adrenergic receptors in panic disorder.     

Change in optic disk topography after trabeculectomy

PURPOSE: To investigate the relationship between optic disk topography and intraocular pressure before and after trabeculectomy with confocal scanning laser ophthalmoscopy. METHODS: The eyes of 49 consecutive patients undergoing trabeculectomy at a university-based glaucoma practice underwent preoperative and postoperative imaging using a confocal scanning laser ophthalmoscope (Heidelberg Retina Tomograph). Three images of one eye of each patient were obtained with a 15-degree field of view. Preoperative images were obtained approximately 2 months before surgery (mean +/- SD, 2.4 +/- 1.6 months). Postoperative images were obtained at least 3 months after surgery (mean, 4.5 +/- 2.6 months). RESULTS: Mean preoperative intraocular pressure, postoperative intraocular pressure, and percent change in intraocular pressure respectively were 23.1 +/- 6.8 mm Hg, 12.7 +/- 7.1 mm Hg, and 43.8% +/- 29.9%. A significant association (P < .01) was found between percent decrease in intraocular pressure and decreases in cup area, cup volume, and cup/disk area ratio as well as between percent decrease in intraocular pressure and increases in rim area, rim volume, mean height contour, retinal cross-section area, and height in contour. Between 11.7% and 31.2% of the variability (R2) in these parameters was explained by the percent change in intraocular pressure. Topography changes were more strongly associated with percent change than with mean change in intraocular pressure. We found no association between percent decrease in intraocular pressure and reference plane height or maximum cup depth. CONCLUSIONS: Changes in optic nerve topography were associated with reduction in intraocular pressure after trabeculectomy.     

Neuropsychologic findings in cocaine-dependent outpatients

1. Nineteen recently abstinent cocaine-dependent males were compared to 16 control subjects on a battery of neuropsychological tests. 2. The performance of cocaine-dependent subjects was inferior to the control group on tasks assessing higher level verbal skills, and on a task requiring logical sequencing of complex visual stimuli. 3. Cocaine users also performed poorly on a delayed visual memory task and on a verbal generation task, but performed better than the control group on a task assessing simple visual-motor speed. 4. Possible reasons for these findings are discussed, as are the treatment implications of these findings.     

Recent trauma in psychiatric outpatients

Psychiatric clinic outpatients were screened for recent traumatic events, and post-traumatic symptomatology was evaluated in those reporting occurrence of one or more events within the two years prior to screening. Clear symptoms of post-traumatic stress disorder were revealed in 18% of the reporting patients, and the distribution of diagnoses was found to be different in the trauma-reporting group than it was in a comparison diagnostic group.     

Guilt in depressed outpatients.

This study was designed to determine whether normal control subjects (n?=?17) and depressed outpatients (n?=?72) differed with respect to the extent and conditions under which they reported dysfunctional guilt. Depressed outpatients reported significantly more guilt than normal control subjects in most types of situations. A family history of depression was related to a higher overall level of guilt in patients. Course and severity of depression and endogenous subtype did not relate to the amount of guilt reported by the patients. This study provides clinical norms on the Situational Guilt Scale (SGS) of E. T. Klass (see record 1988-15740-001) for a sample of unipolar, nonpsychotic outpatients with major depressive disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of mitomycin C on aqueous humor flow, flare and intraocular pressure in eyes with glaucoma 2 years after trabeculectomy

BACKGROUND: The purpose of this study was to determine the intraocular pressure (IOP), aqueous humor flow, flare and ocular side effects in eyes with a history of hypotony after trabeculectomy with adjunctive mitomycin C (MMC). METHODS: Thirty-six eyes with primary or secondary open-angle glaucoma and IOP < or = 8 mmHg during the postoperative period were studied 745 +/- 315 days after surgery. MMC (0.2 or 0.5 mg/ml) was applied to the episclera with a cellular sponge. Flare was studied with the Kowa Laser Flare Meter 500. Aqueous humor flow was measured in the afternoon (Fluorotron Master II). IOP, visual fields and best corrected visual acuity were also examined. Twenty-two contralateral eyes without surgical intervention served as controls. RESULTS: The mean age of patients was 44.5 +/- 16.8 years. The mean IOP was significantly lower in the MMC group than in the control group: 9.6 +/- 6.4 mmHg vs 18.0 +/- 13.6 mmHg at 2 years (P < 0.001). Aqueous flow was significantly lower in subjects treated with MMC than in controls (P < 0.001). The flare values were significantly higher in the MMC-treated group, with a mean of 12.0 +/- 7.7 photon counts/ms, than in the control group, mean 7.9 +/- 4.6 photon counts/ms (P < 0.019). CONCLUSION: Our data suggest that MMC is a useful ocular hypotensive agent which seems to participate in a change in aqueous humor dynamics when applied topically as an aqueous solution.