Recurrent shock and pulmonary edema due to acetazolamide medication after cataract surgery

Acetazolamide-induced pulmonary oedema: A disproportionality analysis from the EudraVigilance database

To our knowledge, no prior study has analysed a possible association between acetazolamide and pulmonary oedema. The aim of this study was to use data from the EudraVigilance to detect a safety signal for acetazolamide-induced pulmonary oedema. We performed a disproportionality analysis (case-noncase method), calculating reporting odds ratios (RORs) up to 22 February 2024. Among 11 684 208 spontaneous cases of adverse reactions registered in EudraVigilance, 38 275 were pulmonary oedemas. Acetazolamide was involved in 31 cases. In more than half of those cases, the patients received a single dose of acetazolamide after undergoing cataract surgery: latency was 10-90 min. Remarkably, there were five cases of positive rechallenge and six cases resulted in death. The ROR for acetazolamide was 3.63 (95% CI 2.55-5.17). Disproportionality was also observed in VigiBase®: ROR 4.44 (95% CI 3.34-5.90). Our study confirms a signal that suggests a risk of serious pulmonary oedema associated with acetazolamide.

Outcome prediction of pediatric moyamoya disease using midterm cerebral blood flow measured between staged anastomoses

PURPOSE

Cognitive outcomes of pediatric moyamoya disease are variable and difficult to predict on the basis of initial neurological signs and examinations. To determine the best early time point for outcome prediction, we retrospectively analyzed the correlation between cognitive outcomes and the cerebrovascular reserve capacity (CRC) measured before, between, and after staged bilateral anastomoses.

METHODS

Twenty-two patients aged 4-15 years were included in this study. CRC was measured before the first hemispheric surgery (preoperative CRC), 1 year after the first surgery (midterm CRC), and 1 year after the surgery on the other side (final CRC). The cognitive outcome was the Pediatric Cerebral Performance Category Scale (PCPCS) grade more than 2 years after the final surgery.

RESULTS

The 17 patients with favorable outcomes (PCPCS grades 1 or 2) showed a preoperative CRC of 4.9% ± 11.2%, which was not better than that of the five patients with unfavorable outcomes (grade 3; 0.3% ± 8.5%, p = 0.5). The 17 patients with favorable outcomes showed a midterm CRC of 23.8% ± 15.3%, which was significantly better than that of the five patients with unfavorable outcomes (-2.5% ± 12.1%, p = 0.004). The difference was much more significant for the final CRC, which was 24.8% ± 13.1% in the patients with favorable outcomes and -11.3% ± 6.7% in those with unfavorable outcomes (p = 0.00004).

CONCLUSION

Cognitive outcomes were first clearly discriminated by the CRC after the first-side unilateral anastomosis, which is the optimal early timing for the prediction of individual prognosis.

Acetazolamide induced noncardiogenic pulmonary edema, an underreported serious adverse event

Purpose

To report a case of acute noncardiogenic pulmonary edema (NCPE) after administration of acetazolamide post routine cataract surgery.

Observations

30 minutes after administration of oral acetazolamide, the patient experienced abdominal pain, nausea, vomiting, diarrhea, and diaphoresis. The patient was taken to the emergency room where she was found to have pulmonary edema. After life threatening respiratory failure resulting in prolonged intubation, the patient was eventually discharged from the hospital.

Conclusions and importance

NCPE is a rare but severe adverse effect of acetazolamide and should be considered when prescribing such agents.

Noncardiogenic pulmonary edema in small animals

OBJECTIVE

To review various types of noncardiogenic pulmonary edema (NCPE) in cats and dogs.

ETIOLOGY

NCPE is an abnormal fluid accumulation in the lung interstitium or alveoli that is not caused by cardiogenic causes or fluid overload. It can be due to changes in vascular permeability, hydrostatic pressure in the pulmonary vasculature, or a combination thereof. Possible causes include inflammatory states within the lung or in remote tissues (acute respiratory distress syndrome [ARDS]), airway obstruction (post-obstructive pulmonary edema), neurologic disease such as head trauma or seizures (neurogenic pulmonary edema), electrocution, after re-expansion of a collapsed lung or after drowning.

DIAGNOSIS

Diagnosis of NCPE is generally based on history, physical examination, and diagnostic imaging. Radiographic findings suggestive of NCPE are interstitial to alveolar pulmonary opacities in the absence of signs of left-sided congestive heart failure or fluid overload such as cardiomegaly or congested pulmonary veins. Computed tomography and edema fluid analysis may aid in the diagnosis, while some forms of NCPE require additional findings to reach a diagnosis.

THERAPY

The goal of therapy for all types of NCPE is to preserve tissue oxygenation and reduce the work of breathing. This may be achieved by removing the inciting cause (eg, airway obstruction) and cage rest in mild cases and supplemental oxygen in moderate cases and may require mechanical ventilation in severe cases.

PROGNOSIS

Prognosis is generally good for most causes of veterinary NCPE except for ARDS, although data are scarce for some etiologies of NCPE.

Impact of Acetazolamide on Perioperative Pain Control in Robotic Assisted Laparoscopic Prostatectomy

OBJECTIVE

To evaluate the efficacy of peri-operative acetazolamide for pain control in robotic assisted laparoscopic prostatectomy (RALP). Prior studies have demonstrated that preoperative acetazolamide decreased postoperative referred pain in the postsurgical period for laparoscopic procedures. The proposed mechanism is acetazolamide mediated inhibition of carbonic anhydrase, thereby preventing formation of carbonic acid and subsequent peritoneal acidosis with referred pain. This has yet to be demonstrated in the setting of RALP.

METHODS AND MATERIALS

Patients undergoing RALP were randomized to receive either preoperative saline or acetazolamide prior to the procedure. Overall pain scores were recorded at multiple time points post operatively, as well as total morphine equivalents administered for adjunctive pain control.

RESULTS

Thirty-one patients were included in the study: 16 patients (51.6%) received perioperative acetazolamide, and 15 patients (48.4%) received perioperative saline as placebo. Overall pain scores were similar for patients receiving acetazolamide compared to placebo at various time points: first responsive (3.5 ± 3.1 vs 4.1 ± 1.7, P = .28), immediately prior to leaving PACU (2.8 ± 2.9 vs 2.9 ± 2.9, P = .48), at 4 hours post-procedure (3.1 ± 3.0 vs 2.9 ± 1.8, P = .362), or at 24 hours post-procedure (2.3 ± 1.7 vs 2.2 ± 1.6, P = .5). Shoulder tip pain was not present in either cohort. No statistically significant difference was observed for total morphine equivalents delivered between acetazolamide and placebo (17.3 vs 20.5, P= .2, respectively).

CONCLUSION

Acetazolamide does not appear to impact overall pain or shoulder tip pain in the observed cohort of patients undergoing RALP.

Macrohistory of Moyamoya Disease Analyzed Using Artificial Intelligence

INTRODUCTION

Moyamoya disease is characterized by progressive stenotic changes in the terminal segment of the internal carotid artery and the development of abnormal vascular networks called moyamoya vessels. The objective of this review was to provide a holistic view of the epidemiology, etiology, clinical findings, treatment, and pathogenesis of moyamoya disease. A literature search was performed in PubMed using the term "moyamoya disease," for articles published until 2021.

RESULTS

Artificial intelligence (AI) clustering was used to classify the articles into 5 clusters: (1) pathophysiology (23.5%); (2) clinical background (37.3%); (3) imaging (13.2%); (4) treatment (17.3%); and (5) genetics (8.7%). Many articles in the "clinical background" cluster were published from the 1970s. However, in the "treatment" and "genetics" clusters, the articles were published from the 2010s through 2021. In 2011, it was confirmed that a gene called Ringin protein 213 (RNF213) is a susceptibility gene for moyamoya disease. Since then, tremendous progress in genomic, transcriptomic, and epigenetic profiling (e.g., methylation profiling) has resulted in new concepts for classifying moyamoya disease. Our literature survey revealed that the pathogenesis involves aberrations of multiple signaling pathways through genetic mutations and altered gene expression.

CONCLUSION

We analyzed the content vectors in abstracts using AI, and reviewed the pathophysiology, clinical background, radiological features, treatments, and genetic peculiarity of moyamoya disease.

Oral acetazolamide for intraocular pressure lowering: balancing efficacy and safety in ophthalmic practice

Introduction: Systemic acetazolamide is an efficacious adjunct to topical therapy to lower intraocular pressure (IOP) in glaucomatous eyes. This article aims to provide a comprehensive review for how best to use the agent in ophthalmic practice.Areas covered: This article will review the history, mechanism of action, methods of observing efficacy, indications for IOP lowering, side effects, allergy information including discussion of limited cross-reactivity between antimicrobial and non-antimicrobial sulfonamides, formulations, dosing and monitoring of acetazolamide. To select articles for this review, an electronic search was conducted using the PubMed database and cross-referencing was conducted for relevant literature.Expert opinion: The benefits of oral carbonic anhydrase inhibitor therapy can outweigh the risks in many circumstances. It is important that eye care practitioners work together with a patient's primary care practitioner to monitor for and mitigate risks. Greater education is needed with regard to the allergy profile of these powerful agents. Though not often a first-line option, oral carbonic anhydrase inhibitors remain pivotal and play in important role in delivery of eye care.

Hypocapnia Induced by Hyperventilation with Indocyanine Green Kinetics Detects the Effect of Staged Carotid Angioplasty to Avoid Hyperperfusion in Patients with Impaired Cerebral Hemodynamic Reserve

Cerebral hyperperfusion syndrome (CHS) is a serious complication following carotid artery stenting (CAS). Staged angioplasty (AP) could potentially prevent CHS and hyperperfusion phenomenon (HPP) after revascularization. However, methods for measuring the effects of staged AP on cerebral hemodynamic reserve have not been established. Here, we evaluated whether indocyanine green kinetics and near-infrared spectroscopy (ICG-NIRS) with hypocapnia induced by hyperventilation can detect the effects of staged AP on hemodynamic reserve to prevent CHS after CAS. Participants comprised 44 patients at high risk of CHS, whose ipsilateral cerebrovascular reactivity (CVR) was impaired on preoperative single photon emission computed tomography (SPECT). Patients were divided into a staged AP group (n=13) and a regular CAS group (n=31). In the staged AP group, stenting was performed 3 weeks after staged AP. In the regular CAS group, 16 cases (52%) showed HPP, and five (16%) presented with CHS after CAS, while no HPP or CHS occurred in the staged AP group (p=0.001). Changes in blood flow index (BFI) and time to peak (TTP) ratio during hypocapnia calculated from ICG-NIRS indicated a significant linear relationship with preprocedural CVR on SPECT (r=-0.710, 0.632, respectively; p<0.0001 each). BFI and TTP ratios during hypocapnia were significantly improved after staged AP (p<0.001 each). Furthermore, significant linear correlations were observed between BFI and TTP ratio during hypocapnia and postoperative asymmetry index AI (r=0.405, -0.475, respectively; p<0.01 each). Hypocapnia induced by hyperventilation under ICG-NIRS appears useful for detecting the effects of staged AP on hemodynamic reserve in patients at high risk of CHS.

Assessment of cerebrovascular reserve with N-isopropyl-p-[123I]-iodoamphetamine time series analysis in patients with cerebrovascular disease

Using N-isopropyl-p-[123I]-iodoamphetamine(123I-IMP) and single-photon emission computed tomography (SPECT), the relationship between cerebrovascular reserve and the 123I-IMP redistribution phenomenon was investigated.The 50 patients who matched the inclusion criteria were divided into control and ischemia groups, and the redistribution phenomenon was examined on resting images. The delayed images showed higher 123I-IMP accumulation in lesions in the middle cerebral artery(MCA) area and anterior cerebral artery(ACA) area, these watershed areas in the ischemia group than in the control group, confirming that the redistribution phenomenon exists with statistical significance (Wilcoxon test; control group vs ischemic group in the ACA area[P = .002], ACA-MCA watershed area(P = .014), MCA area(P = .025), and MCA-posterior cerebral artery(PCA) watershed area(P = .002). The patients were then divided into 4 types according to the Kuroda grading system, and the difference in the redistribution phenomenon was investigated between type III and the other 3 types.Compared with type I and type II, type III had a significantly lower rate of decrease in the radioisotope (RI) count, verifying the redistribution phenomenon (Student t test: type I vs type III in the ACA area(P = .008), ACA-MCA watershed area(P = .009), MCA area(P < .001), and MCA-PCA watershed area(P = .002); type II vs type III in the ACA area(P = .004), ACA-MCA watershed area(P = .2575), MCA area(P < .001), and MCA-PCA watershed area(P < .001). No significant difference between type III and type IV was observed in any area [(Student t test: type III vs type IV in the ACA area(P = .07), ACA-MCA watershed area(P = .38), MCA area(P = .05), and MCA-PCA watershed area(P = .24)].The redistribution phenomenon is associated with resting cerebral blood flow (CBF), but not necessarily with cerebral vascular reactivity (CVR).

Usefulness of 2D-Perfusion Analysis for the Assessment of Unilateral Cervical Internal Carotid Artery Stenosis

Objective

We investigated the usefulness of 2D-perfusion analysis for the evaluation of cerebral blood flow in unilateral cervical internal carotid artery stenosis.

Methods

We conducted a 2D-perfusion analysis during cerebral angiography and ¹²³I-iodoamphetamine (IMP) single photon emission computed tomography (SPECT) for unilateral cervical internal carotid artery stenosis without contralateral stenosis. The relationship between the ratio of the lesion side to the normal side in the parameters obtained by 2D-perfusion and the value calculated by stereotactic extraction estimation (SEE) analysis of SPECT was statistically examined.

Results

The ratios of the lesion side to the normal side regarding the peak arrival time (AT; time to peak [TTP]) of the contrast agent and the mean filling time (mean transit time [MTT]) of the contrast agent in 2D-perfusion significantly correlated with the area of Stage II and increase ratio (I.R) ≤30% in the SEE analysis (p = 0.002, 0.003).

Conclusion

2D-perfusion analysis can be used to estimate the extent of impaired cerebrovascular reserve (CVR) area in unilateral internal carotid artery stenosis.

Resting-state Functional Magnetic Resonance Imaging Identifies Cerebrovascular Reactivity Impairment in Patients With Arterial Occlusive Diseases: A Pilot Study

BACKGROUND

The development of noninvasive approaches for identifying hypoperfused brain tissue at risk is of major interest. Recently, the temporal-shift (TS) maps estimated from resting-state blood oxygenation level-dependent (BOLD) signals have been proposed for determining hemodynamic state.

OBJECTIVE

To examine the equivalency of the TS map and the cerebrovascular reactivity (CVR) map derived from acetazolamide-challenged single-photon emission computed tomography (SPECT) in identifying hemodynamic impairment in patients with arterial occlusive diseases.

METHODS

Twenty-three patients with arterial occlusive diseases who underwent SPECT were studied. With a recursive TS analysis of low-frequency fluctuation of the BOLD signal, a TS map relative to the global signal was created for each patient. The voxel-by-voxel correlation coefficient was calculated to examine the image similarity between TS and SPECT-based cerebral blood flow (CBF) or CVR maps in each patient. Furthermore, simple linear regression analyses were performed to examine the quantitative relationship between the TS of BOLD signals and CVR in each cerebrovascular territory.

RESULTS

The within-patient, voxel-by-voxel comparison revealed that the TS map was more closely correlated with SPECT-CVR map ([Z(r)] = 0.42 ± 0.18) than SPECT-CBF map ([Z(r)] = 0.058 ± 0.11; P < .001, paired t-test). The regression analysis showed a significant linear association between the TS of BOLD signals and CVR in the anterior circulation where the reduction of CVR was evident in the patient group.

CONCLUSION

BOLD TS analysis has potential as a noninvasive alternative to current methods based on CVR for identification of tissue at risk of ischemic stroke.

Hemodynamic study about cortical hyperintensity belt sign after direct bypass surgery for moyamoya disease

Transient neurological events (TNEs) are observed after direct bypass surgery in patients with moyamoya disease (MMD). Although a correlation between cortical hyperintensity belt signs (CHBs) and TNEs has been reported, the pathophysiology of CHBs is still unknown. The purpose of this study was to reveal the pathophysiology of CHBs by using dynamic susceptibility contrast-magnetic resonance imaging. Thirty patients with MMD were included in this study. We provided scores (0-2) for the existence of CHBs on postoperative FLAIR images. We placed the ROI for the presented area of CHBs in the images of cerebral blood flow, CBV, and MTT. We calculated the change of the hemodynamic parameters (increase ratio, IR) and analyzed the relationship between IRs, CHB scores, and TNEs. TNEs were observed in 15 cases (50%) and CHBs were detected in 28 cases (93%). TNEs showed significantly higher CHB scores than those without (p < 0.05). The group of CHB score 2 showed a significantly higher CBV IR than the group with of score 0 (p < 0.05). Patients with TNEs showed a significantly higher CBV IR than those without (p < 0.05). As for the cut-off level to predict an appearance of TNEs, the CBV IR was 1.36 by the Receiver Operating Characteristic analysis, and the sensitivity and specificity were 80% respectively. We hypothesize that the pathophysiology of the CHBs are vasogenic edemas because the postoperative CBV increase correlated with the CHBs.

Basal and Acetazolamide Brain Perfusion SPECT in Internal Carotid Artery Stenosis

Internal carotid artery (ICA) stenosis including Moyamoya disease needs revascularization when hemodynamic insufficiency is validated. Vascular reserve impairment was the key to find the indication for endarterectomy/bypass surgery in the atherosclerotic ICA stenosis and to determine the indication, treatment effect, and prognosis in Moyamoya diseases. Vascular reserve was quantitatively assessed by 1-day split-dose I-123 IMP basal/acetazolamide SPECT in Japan or by Tc-99m HMPAO SPECT in other countries using qualitative or semi-quantitative method. We summarized the development of 1-day basal/ acetazolamide brain perfusion SPECT for ICA stenosis, both quantitative and qualitative methods, and their methodological issues regarding (1) acquisition protocol; (2) qualitative assessment, either visual or deep learning-based; (3) clinical use for atherosclerotic ICA steno-occlusive diseases and mostly Moyamoya diseases; and (4) their impact on the choice of treatment options. Trials to use CT perfusion or perfusion MRI using contrast materials or arterial spin labeling were briefly discussed in their endeavor to use basal studies alone to replace acetazolamide-challenge SPECT. Theoretical and practical issues imply that basal perfusion evaluation, no matter how much sophisticated, will not disclose vascular reserve. Acetazolamide rarely causes serious adverse reactions but included fatality, and now, we need to monitor patients closely in acetazolamide-challenge studies.

Paradoxical Critical Hyperkalemia After Acetazolamide for Cerebrovascular Reactivity Study: A Case Report

We present the case of a 42-year-old man with moyamoya disease presenting for cerebral revascularization surgery who developed critical hyperkalemia following a single intravenous (iv) dose of 1000 mg of acetazolamide 1 day preoperatively for a cerebrovascular reactivity study. His potassium increased from 5.1 to 6.7 mmol/L. Prompt treatment of this abnormality allowed this patient to undergo surgery the next day uneventfully. A paradoxical, critical increase in potassium can result from a single 1000-mg iv dose of acetazolamide.

Hemodynamic stress distribution identified by SPECT reflects ischemic symptoms of Moyamoya disease patients

This study aimed to validate the hypothesis that the ratio of cerebral blood flow (CBF) at rest in the lenticular nucleus (LN) territory to that in the middle cerebral artery (MCA) territory is higher in symptomatic Moyamoya disease (MMD) patients than in asymptomatic MMD patients. This was a retrospective observational study of adult patients with documented MMD who underwent single-photon emission computed tomography (SPECT) and had been examined at the Department of Neurosurgery of Keio University Hospital during a 10-year period (2006-2016). The diagnosis was made on the basis of typical imaging findings. We classified unoperated MMD patients into three groups: class I, no evidence of stenosis or occlusion hemispheres and without symptoms in unilateral MMD patients; class II, hemispheres with stenosis or occlusion but without ischemic symptoms; and class III, hemispheres with evidence of stenosis or occlusion associated with ischemic symptoms. Hemodynamic stress distribution (hdSD) was defined as the ratio of CBF in one LN to the CBF in the peripheral MCA; this was obtained by SPECT at rest. We compared the values of CBF and hdSD among the groups. A total of 173 adult patients were diagnosed with MMD from January 1, 2006, to January 1, 2016. Among them, 85 MMD patients underwent SPECT studies. After excluding inappropriate cases, 144 hemispheres were included in our analysis. hdSD was significantly higher (p < 0.001) in hemispheres with ischemic symptoms (class III, mean hdSD = 1.1; 36 sides) than in those without symptoms (class II, mean hdSD = 1.03; 82 sides). However, CBF at rest in the MCA or LN was not significantly associated with ischemic symptoms. The optimal threshold for hdSD to have ischemic symptoms was 1.040 (area under the curve; 74% sensitivity 91.7% and specificity 54.9%). We used SPECT to investigate cerebral blood from MMD patients and found that high hdSD values were predictive of ischemic symptom development in these patients.

Acetazolamide as a potent chloride-regaining diuretic: short- and long-term effects, and its pharmacologic role under the 'chloride theory' for heart failure pathophysiology

According to the "chloride theory" for heart failure (HF) pathophysiology, manipulation of the serum chloride concentration is an important therapeutic target. This study determined the short- and long-term effects of acetazolamide (Diamox), a potential chloride-regaining diuretic, on peripheral blood, serum electrolytes, and renal function. Effects of low-dose Diamox (250-500 mg/day) were evaluated in 30 HF patients for whom Diamox was added as de-novo/add-on decongestion therapy for acutely worsening HF (n = 18) or as modification therapy for serum hypochloremia in stable HF ( < 100 mEq/L; n = 12). Peripheral hematologic tests were performed at baseline, and at short- ( ≤ 10 days) and long-term ( ~ 60 days) time-points. In all 30 study patients of both groups, the serum chloride concentration increased in the short-term and even further over the long-term. The serum potassium concentration constantly decreased throughout the study period. Both the blood urea nitrogen and serum creatinine concentrations increased in the short-term, but returned to baseline levels over the long-term. Responders to Diamox (n = 13; defined by HF resolution and body weight loss ≥ 1 kg) in the decongestion group exhibited reduced serum b-type natriuretic peptide levels and a markedly increased serum chloride concentration, but the hemoglobin/hematocrit and serum creatinine concentrations did not change after treatment. In conclusion, acetazolamide is a potent candidate "chloride-regaining diuretic" for treating HF patients under the "chloride theory". Its effect to enhance the serum chloride concentration occurred within 10 days and persisted for at least ~ 60 days. Plasma volume and renal function were preserved under adequate diuretic treatment with acetazolamide.

Hyperventilation and breath-holding test with indocyanine green kinetics predicts cerebral hyperperfusion after carotid artery stenting

Cerebral hyperperfusion syndrome (CHS) is a serious complication following carotid artery stenting (CAS), but definitive early prediction of CHS has not been established. Here, we evaluated whether indocyanine green kinetics and near-infrared spectroscopy (ICG-NIRS) with hyperventilation (HV) and the breath-holding (BH) test can predict hyperperfusion phenomenon after CAS. The blood flow index (BFI) ratio during HV and BH was prospectively monitored using ICG-NIRS in 66 patients scheduled to undergo CAS. Preoperative cerebrovascular reactivity (CVR) and the postoperative asymmetry index (AI) were also assessed with single-photon emission computed tomography before and after CAS and the correlation with the BFI HV/rest ratio, BFI BH/rest ratio was evaluated. Twelve cases (18%) showed hyperperfusion phenomenon, and one (1.5%) showed CHS after CAS. A significant linear correlation was observed between the BFI HV/rest ratio, BFI BH/rest ratio, and preoperative CVR. A significant linear correlation was observed between the BFI HV/rest ratio and postoperative AI (r = 0.674, P < 0.0001). A BFI HV/rest ratio of 0.88 or more was the optimal cut-off point to predict hyperperfusion phenomenon according to receiver operating characteristic curve analyses. HV and BH test under ICG-NIRS is a useful tool for detection of hyperperfusion phenomenon in patients who underwent CAS.

Measurement of oxygen extraction fraction by blood sampling to estimate severe cerebral hemodynamic failure and anticipate cerebral hyperperfusion syndrome following carotid artery stenting

BACKGROUND

Cerebral hyperperfusion syndrome (CHS) is likely to occur after carotid revascularization in patients with stage 2 hemodynamic failure (st2HF), in whom the oxygen extraction fraction (OEF) increases.

OBJECTIVE

The purpose of our study was to investigate whether measurement of the global cerebral OEF (gcOEF) by blood sampling can be used to estimate st2HF and anticipate CHS following carotid artery stenting (CAS).

METHODS

The OEF was calculated by blood sampling just before and after elective CAS. Data were collected prospectively. Patients who underwent elective CAS and gcOEF calculation were included in the study. Patients' baseline features, pre-CAS gcOEF, post-CAS gcOEF, and incidence of CHS (defined as headache, seizure, focal neurologic deficits, and/or restlessness) were evaluated.

RESULTS

141 patients met the inclusion criteria and 134 patients were analyzed. Median pre-CAS gcOEF and post-CAS gcOEF were 0.41 and 0.42, respectively. Nine patients developed CHS. Median pre-CAS gcOEF was higher in patients with than in those without CHS (Mann-Whitney U test, P<0.05), but median post-CAS gcOEF was not significantly higher in patients with CHS (P=0.058). Scattergrams of patients with and without CHS showed that the cut-off values of the pre-CAS gcOEF and post-CAS gcOEF for anticipation of CHS were 0.46 (P<0.01) and 0.49 (P<0.001), respectively.

CONCLUSION

Elevation of the pre-CAS or post-CAS gcOEF by blood sampling allowed for anticipation of CHS following CAS. Elevation of the pre-CAS gcOEF might be associated with st2HF.

Can Arterial Spin-Labeling with Multiple Postlabeling Delays Predict Cerebrovascular Reserve?

BACKGROUND AND PURPOSE

The effect of delayed transit time is the main source of error in the quantitative measurement of CBF in arterial spin-labeling. In the present study, we evaluated the usefulness of the transit time-corrected CBF and arterial transit time delay from multiple postlabeling delays arterial spin-labeling compared with basal/acetazolamide stress technetium Tc99m-hexamethylpropylene amineoxime (Tc99m-HMPAO) SPECT in predicting impairment in the cerebrovascular reserve.

MATERIALS AND METHODS

Transit time-corrected CBF maps and arterial transit time maps were acquired in 30 consecutive patients with unilateral ICA or MCA steno-occlusive disease (severe stenosis or occlusion). Internal carotid artery territory-based ROIs were applied to both perfusion maps. Additionally, impairment in the cerebrovascular reserve was evaluated according to both qualitative and quantitative analyses of the ROIs on basal/acetazolamide stress Tc99m-HMPAO SPECT using a previously described method. The area under the receiver operating characteristic curve was used to evaluate the diagnostic accuracy of arterial spin-labeling in depicting impairment of the cerebrovascular reserve. The correlation between arterial spin-labeling and cerebrovascular reserve was evaluated.

RESULTS

The affected hemisphere had a decreased transit time-corrected CBF and increased arterial transit time compared with the corresponding values of the contralateral normal hemisphere, which were statistically significant (P < .001). The percentage change of transit time-corrected CBF and the percentage change of arterial transit time were independently differentiating variables (P < .001) for predicting cerebrovascular reserve impairment. The correlation coefficient between the arterial transit time and cerebrovascular reserve index ratio was -0.511.

CONCLUSIONS

Our results demonstrate that the transit time-corrected CBF and arterial transit time based on arterial spin-labeling perfusion MR imaging can predict cerebrovascular reserve impairment.

Correlation between Clinical Presentations and Hemodynamic Parameters Measured by Dynamic Susceptibility Contrast Magnetic Resonance Imaging in Adult Patients with Moyamoya Disease

BACKGROUND

The examination of cerebral hemodynamics is indispensable for the clinical management of patients with moyamoya disease (MMD). In this study, we examined the correlation between clinical presentations and hemodynamic parameters measured by dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in adult patients with MMD.

METHODS

One hundred fifty-seven hemispheres in 122 adult patients with MMD were examined by DSC-MRI to measure the regional relative cerebral blood volume (CBV) and relative mean transit time (MTT). The patients were divided into 4 groups based on their clinical presentations: a nonsymptomatic (NS), hemorrhagic (H), infarction (I), and transient ischemic attack (T) group. The regional CBV and MTT values were compared among the 4 groups.

RESULTS

The relative value of CBV was significantly higher in groups T and I than in the NS group (P < .01). The CBV of group H was higher than that of the NS group only in the frontal lobe cortex. There were no significant statistical differences among the 3 symptomatic groups. Prolongation of the MTT in comparison with the cerebellum (MTT delay) was significantly higher in groups T and I than in the NS group in all regions of the cerebral cortex (P < .05). The MTT delay was significantly lower in group H than in group T in the frontal lobe and the Rolandic area (P < .05).

CONCLUSIONS

Hemodynamic factors measured by DSC-MRI reflected the variable clinical presentations of patients with MMD. DSC-MRI is a useful modality for evaluating the clinical conditions of individual adult patients with MMD.

A case of non-cardiogenic pulmonary edema provoked by intravenous acetazolamide

Case

A 61‐year‐old man was diagnosed with severe chest trauma after a car accident and had had difficulty in weaning from a ventilator because of flail chest and dilated cardiomyopathy. On the 17th day in the intensive care unit, he received i.v. acetazolamide to increase urine output. One hour after the injection, he suddenly developed severe hypoxia. Chest radiography revealed a butterfly shadow. He received other diuretics and a vasodilator, which seemed slowly to resolve the respiratory failure. Five days later, acetazolamide was again given and he experienced the same deterioration.

Outcome

We concluded that the episodes were attributed to pulmonary edema provoked by acetazolamide.

Conclusion

Acute non‐cardiogenic pulmonary edema is an uncommon and lethal adverse effect of acetazolamide. Careful attention may be warranted when administering acetazolamide to critically ill patients.

Efficacy and safety of preoperative IOP reduction using a preservative-free fixed combination of dorzolamide/timolol eye drops versus oral acetazolamide and dexamethasone eye drops and assessment of the clinical outcome of trabeculectomy in glaucoma

Introduction

To demonstrate that preoperative treatment for 28 days with topical dorzolamide/timolol is non-inferior (Δ = 4 mm Hg) to oral acetazolamide and topical dexamethasone (standard therapy) in terms of intraocular pressure (IOP) reduction 3 and 6 months after trabeculectomy in glaucoma patients.

Materials and methods

Sixty-two eyes undergoing trabeculectomy with mitomycin C were included in this monocentric prospective randomized controlled study. IOP change between baseline and 3 months post-op was defined as the primary efficacy variable. Secondary efficacy variables included the number of 5-fluorouracil (5-FU) injections, needlings, suture lyses, preoperative IOP change, hypertension rate and change of conjunctival redness 3 and 6 months post-op. Safety was assessed based on the documentation of adverse events.

Results

Preoperative treatment with topical dorzolamide/timolol was non-inferior to oral acetazolamide and topical dexamethasone in terms of IOP reduction 3 months after trabeculectomy (adjusted means -8.12 mmHg versus -8.30 mmHg; Difference: 0.18; 95% CI -1.91 to 2.26, p = 0.8662). Similar results were found 6 months after trabeculectomy (-9.13 mmHg versus -9.06 mmHg; p = 0.9401). Comparable results were also shown for both groups concerning the classification of the filtering bleb, corneal staining, and numbers of treatments with 5-FU, needlings and suture lyses. More patients reported AEs in the acetazolamide/dexamethasone group than in the dorzolamide/timolol group.

Discussion

Preoperative, preservative-free, fixed-dose dorzolamide/timolol seems to be equally effective as preoperative acetazolamide and dexamethasone and has a favourable safety profile.

Assessment of Hemodynamic Compromise Using Computed Tomography Perfusion in Combination with 123I-IMP Single-Photon Emission Computed Tomography without Acetazolamide Challenge Test

OBJECTIVES

The acetazolamide challenge test in conjunction with ¹²³I-IMP single-photon emission computed tomography (SPECT) is a known method of assessing cerebrovascular reserve capacity. In this study, we investigated whether CT perfusion in combination with resting state ¹²³I-IMP SPECT could be used instead of the acetazolamide challenge test to evaluate hemodynamic compromise in patients with atherosclerotic occlusive disease.

METHODS

Twenty consecutive patients with unilateral internal carotid artery or middle cerebral artery steno-occlusive disease were enrolled. ¹²³I-IMP SPECT was performed with and without the acetazolamide challenge test, and with CT perfusion. Cerebral blood flow (CBF), cerebral blood volume, and mean transit time (MTT) obtained by CT perfusion were compared with CBF and cerebrovascular reactivity (CVR) obtained by ¹²³I-IMP SPECT.

RESULTS

The asymmetry ratio of MTT as measured by CT perfusion showed a strong correlation with the CVR to acetazolamide as measured by ¹²³I-IMP SPECT (ρ = -.780, P <.001). Based on the CBF obtained through ¹²³I-IMP SPECT and the MTT obtained through CT perfusion, hemodynamic compromise was detected with high sensitivity (1.000) and specificity (.929), and a cutoff value of 30% was found to be suitable for the asymmetry ratio of MTT. MTT prolongation was significantly improved after revascularization surgery in hemodynamic compromise (P = .028).

CONCLUSION

MTT as measured by CT perfusion in combination with CBF as measured by resting state ¹²³I-IMP SPECT may be useful for evaluating hemodynamic compromise as an alternative to the acetazolamide challenge test.

Assessment of cerebrovascular reserve in unilateral middle cerebral artery stenosis using perfusion CT and CO2 inhalation tests

Purpose/Aim of the study: Cerebrovascular reactivity (CVR) is an important marker for assessing cerebrovascular disease. This study assessed the CVR by perfusion computed tomography (CT) and CO₂ inhalation tests in patients with unilateral middle cerebral artery (MCA) stenosis disease.

MATERIALS AND METHODS

Thirty-one patients with unilateral MCA stenosis disease diagnosed by digital subtraction angiography were studied. Patients were divided into two groups according to the degree of stenosis: severe and moderate. The regional cerebral blood flow (CBF) before and after CO₂ inhalation was determined by perfusion CT. Regional CVR values were obtained by the following formula: increase (%) = (post-CBF) - (pre-CBF)/(pre-CBF) × 100%.

RESULTS

No significant differences in the mean CBF in the MCA stenosis region were found between the affected and contralateral sides before the CO₂ inhalation test; after the test, CBF was more significantly decreased on the affected side than on the contralateral side. The changes in CBF on the affected side were categorized into three types: increased CBF (17 cases), decreased CBF (12 cases) and no change in CBF (2 cases). The rate of CVR impairment among severe stenosis patients (13/19) was higher than that among moderate stenosis patients (3/12). CVR was significantly correlated with the degree of stenosis (r = 0.423, P = 0.018).

CONCLUSION

CVR impairment was found in approximately half of patients with unilateral MCA stenosis. Along with an increase in the degree of stenosis, patients with unilateral MCA stenosis were more likely to exhibit CVR impairment. It is important to assess the CVR in patients with unilateral MCA stenosis, especially those with severe stenosis.

Acute pulmonary oedema due to single dose acetazolamide taken after cataract surgery

An increase in intraocular pressure following cataract surgery is very common. The main reason for this condition is viscoelastic agent remaining in the eye, which leads to mechanical obstruction of the trabecular meshwork. Prophylaxis with oral acetazolamide is frequently practised to prevent this early rise in intraocular pressure in the preoperative and postoperative periods. We report a case of an 81-year-old man with acute pulmonary oedema due to prophylactic acetazolamide intake after cataract surgery. The case is presented in order to draw attention to this serious complication.

Acetazolamide reduces postoperative pain following laparoscopic inguinal herniorrhaphy

BACKGROUND

Carbonic acid accumulation, which results from CO2 insufflation, can produce visceral and referred pain in the postoperative setting. Acetazolamide inhibits carbonic anhydrase, an enzyme that accelerates carbonic acid formation. We hypothesized that preoperative administration of acetazolamide would decrease postoperative pain in patients undergoing laparoscopic inguinal herniorrhaphy.

METHODS

A retrospective review was conducted of patients who underwent laparoscopic preperitoneal inguinal herniorrhaphy at the Medical College of Wisconsin between October 2012 and September 2014. Beginning in January 2014, patients began receiving 250 mg of acetazolamide preoperatively; patients prior to that time did not. The visual analog scale (range 0-10) was used to assess both preoperative pain and postoperative pain.

RESULTS

A total of 66 patients underwent laparoscopic inguinal herniorrhaphy during the study interval. Of these, 22 (33 %) patients received acetazolamide preoperatively, and 44 (67 %) were included as controls. Overall mean pain scores were lower in the acetazolamide group (1.9 ± 1.45 vs 2.9 ± 1.5, p = 0.04). Specifically, patients who received acetazolamide reported lower pain scores immediately after surgery (0.6 ± 1.2 vs 1.9 ± 2.3, p = 0.01) and on post-op day one (2.3 ± 0.9 vs 4.0 ± 2.1, p = 0.04). Total morphine equivalents administered to manage postoperative pain were significantly less for the acetazolamide group (4.3 ± 4.8 mg) when compared to the control group (8.9 ± 8.4 mg), p = 0.04. Perioperative complications did not differ between the groups (p = 0.16).

CONCLUSIONS

Acetazolamide appears to reduce pain in the immediate postoperative setting. Patients who received acetazolamide had lower pain scores postoperatively and required fewer narcotics for pain management prior to discharge.

Hemodynamic stress distribution reflects ischemic clinical symptoms of patients with moyamoya disease

OBJECTIVE

Currently, the probability of diagnosing asymptomatic moyamoya disease is increasing. In this study, we consider a less invasive method for predicting future ischemic symptoms in patients with moyamoya disease.

METHODS

We reviewed cerebral blood flow (CBF)-related data obtained by xenon CT imaging (XeCT) in six patients with ischemic-type or asymptomatic moyamoya disease. The data were obtained as volume data using a 320-row CT, and applied to the automated region-of-interest-determining software (3DSRT) and converted to standardized images. Eight CBF-related parameters, including CBF value, cerebrovascular reserve capacity (CVRC), and hemodynamic distribution (hdSD), were compared between asymptomatic hemispheres and ischemic symptomatic hemispheres. A significant difference was determined by a two-sample t test. A difference with p<0.05 was considered significant. When statistically significant differences between parameters of asymptomatic hemispheres and ischemic symptomatic hemispheres were identified, cut-off points were calculated with receiver operating characteristic (ROC) curves. Change in the parameters before and after bypass surgery was also assessed.

RESULTS

Of the eight CBF-related parameters evaluated, statistically significant differences between the asymptomatic hemispheres and ischemic hemispheres were observed in the CBF value of the MCA region (CBF-MCA), both at rest and after acetazolamide loading, and in the hdSD, also both at rest and after acetazolamide loading. Of the four statistically significant parameters, ROC analysis revealed that the hdSD at rest and CBF-MCA after acetazolamide loading were the most sensitive and specific parameters (threshold 1.2, sensitivity 1, specificity 1 for hdSD at rest, and threshold 26.44mL/100g/min, sensitivity 1, specificity 1 for CBF-MCA after acetazolamide loading). From the CBF data obtained both before and after surgery from the three patients who had undergone direct bypass surgeries, the hdSD was higher than the threshold of 1.2 before surgery but decreased to lower than the threshold of 1.2 after surgery. Ischemic symptoms also resolved after surgery.

CONCLUSIONS

The data showed that hdSD at rest and CBF-MCA after acetazolamide loading reflects ischemic symptoms of patients with moyamoya disease. Thus, these parameters could be used as ischemic symptom markers for following patients with moyamoya disease. hdSD at rest is important because it is less invasive and can be performed without acetazolamide loading.