No abstract

Measurement of blood volume, both of its plasma and red cell portion, is a useful tool in clinical and experimental investigation. It provides basic data for the assay of the total quantity of individual blood components, as well as for the evaluation of observed hemodynamic changes in acute or chronic disturbances of the circulation. Blood volume determinations have proved of value in the study of congestive heart failure, the anemias, thyroid disorders, renal disease, and pregnancy; and they have been particularly useful-during the recent war years in the study of hemorrhage, burns and shock, and in the development of blood substitutes and blood cell preservatives.It seems reasonable to state that the dye method (1, 2) measures the circulating plasma volume with a high degree of accuracy both in normal and pathologic states, and in many clinical and experimentally induced abnormal circulatory conditions. This view appears to be shared by investigators who have had firsthand experience with the technique (3, 4).Perhaps the best experimental evidence that the method accurately measures changes in plasma volume was obtained in a series of experiments in which the increase in plasma volume following the intravenous injection of concentrated (25 per cent) human serum albumin was measured (5).The osmotic equivalent of 1 gram of this protein was found by Scatchard et al (6) to be 18 ml. of H20; the average increase in plasma volume in 11 male human subjects was 17.4 ml. of H20 (5) per gram of albumin.

Results of the propensity-matched retrospective analysis suggested that avoiding isoflurane significantly reduced the duration of hospitalization. In contrast, length-of-stay was comparable in our prospective trial. Volatile anesthetic choice should not be based on concerns about the duration of hospitalization. These studies illustrate the importance of following even the best retrospective analysis with a prospective trial.

The delayed-release tablet formulation of posaconazole (POS-tab) results in higher plasma POS trough concentrations (C min ) than the oral suspension (POS-susp), which raises the question of the utility of therapeutic drug monitoring (TDM). We aimed to compare the variability of the POS C min for the two formulations and identify determinants of the POS-tab C min and its variability. Demographic, biological, and clinical data from 77 allogeneic hematopoietic stem cell transplant patients (874 C min ) treated with POS-tab (n ϭ 41), POS-susp (n ϭ 29), or both (n ϭ 7) from January 2015 to December 2016 were collected retrospectively. Interpatient and within-subject coefficients of variation (CVs) of the C min adjusted to dose (D) were calculated for each formulation. Between-group comparisons were performed using a linear mixed effects model. The POS C min was higher for the tablet than for the suspension (median [25th-75th percentile]: 1.8 [1.2-2.4] mg/liter versus 1.2 [0.7-1.6] mg/liter, P Ͻ 0.0001). Interpatient CVs for the tablet and suspension were 60.8 versus 63.5% (P ϭ 0.7), whereas within-subject CVs were 39.7 and 44.9%, respectively (P ϭ 0.3). Univariate analysis showed that age and treatment by POS-tab were significantly and positively associated with the POS C min , whereas diarrhea was associated with a diminished POS C min . Multivariate analysis identified treatment with POS-tab and diarrhea as independent factors of the POS C min , with a trend toward a lower impact of diarrhea during treatment with POS-tab (P ϭ 0.07). Despite increased POS exposure with the tablet formulation, the variability of the POS C min was not significantly lower than that of the suspension. This suggests that TDM may still be useful to optimize tablet POS therapy.

Purpose: Choroidal nevus can cause overlying chronic retinal pigment epithelium (RPE) degenerative features, but frank retinal invasion is exquisitely rare. Procedures: This is a retrospective review of 8 cases of choroidal nevus with retinal invasion with evaluation of clinical and imaging features. Results: At the time of diagnosis of choroidal nevus with retinal invasion, mean patient age was 65 years. Mean tumor basal diameter was 7 mm, and mean thickness was 2.3 mm. Retinal invasion was ophthalmoscopically visible in all eyes. Related features included drusen (n = 4/8) and RPE fibrous metaplasia (n = 2/8). Overlying lipofuscin, subretinal fluid, RPE detachment, and retinal edema were absent. On B-scan ultrasonography, the lesion was dome-shaped (n = 7/7) and echo-dense (n = 6/7). Optical coherence tomography demonstrated outer retinal invasion (n = 8/8) with additional inner retinal invasion (n = 3/8). The tissue was hypoautofluorescent at the site of invasion (n = 6/7). Over a mean follow-up of 40 months, tumor enlargement was detected in 2 eyes and managed with observation (< 1 mm enlargement) or plaque radiotherapy (5 mm enlargement). Nevus hypoautofluorescence was correlated with nevus stability (p = 0.035). Conclusion: Retinal invasion of the choroidal nevus is rare. In this series of 8 cases, only 1 demonstrated transformation to melanoma over a mean interval of 40 months. Long-term monitoring of such lesions is warranted.

The proposed mechanism of Terson’s syndrome is increased intracranial pressure that leads to dilation of the retrobulbar optic nerve and compression of the central retinal vein. Terson’s syndrome has been associated with many conditions that increase intracranial pressure such as venous sinus thrombosis, Moyamoya disease, leukemia, direct head trauma, and intraocular hemorrhage related to shaken baby syndrome. We present a novel case of a patient with recent viral prodrome found to have papilledema and multilayered retinal hemorrhages consistent with Terson syndrome. Computed tomography and magnetic resonance venography of the brain did not reveal any subdural, subarachnoid, or intracranial hemorrhages. However, cerebrospinal fluid analyses were significant for increased opening pressure and elevated protein levels, which were suggestive of viral meningoencephalitis. We describe this case as a Terson-like syndrome because the etiology of intraocular hemorrhage is increased intracranial pressure. However, this case does not fit the traditional presentation of Terson’s syndrome as the intracranial pressure is secondary to meningeal inflammation instead of subdural, subarachnoid, or intracranial hemorrhage. We strongly feel that it is important for physicians to be aware of the link between viral meningoencephalitis and retinal conditions such as Terson-like syndrome because it can facilitate rapid diagnosis and treatment.

The authors describe a case of a previously unreported phenomenon of focal choroidal excavation (FCE) expansion, in absence of inflammation, due to treatment of an associated choroidal neovascular membrane (CNVM). A patient with new type 2 CNVM, treated during 43 months of follow-up with aflibercept, experienced significant expansion of an FCE with conversion from nonconforming to conforming type. FCE is part of the pachychoroid spectrum and the regression of an associated CNVM during aflibercept treatment as seen in the authors' patient may elucidate the pathogenesis of some forms of focal choroidal excavation and their evolution over time. [ Ophthalmic Surg Lasers Imaging Retina . 2020;51:54–57.]

AimsTo characterise and classify the morphological, clinical and tomographic characteristics of focal choroidal excavation (FCE) lesions to determine their prognostic implications.Methods36 eyes with FCE (32 patients) underwent multimodal imaging, including spectral domain optical coherence tomography and fundus autofluorescence. FCE lesions were classified into three subtypes: (1) type 1: myopic (central choroidal thickness: <100 µm), (2) type 2: suspected congenital (central choroidal thickness: 100–200 µm, without associated chorioretinal pathology) and (3) type 3: secondary or acquired (central choroidal thickness: >200 µm, with associated chorioretinal pathology).Results80.6% of eyes were followed longitudinally (26.8±18.8 months). There were 9 type 1 FCEs (myopic), 8 type 2 FCEs (U-shaped, congenital) and 19 type 3 FCEs (V-shaped, secondary). Type 2 FCEs trended towards larger maximum widths (p=0.0563). Type 3 FCEs were associated with central serous chorioretinopathy or pachyvessels (47.4%), but were also seen in pattern dystrophy, geographic atrophy, inactive choroiditis, torpedo maculopathy and adult-onset vitelliform dystrophy. Choroidal neovascular membranes (CNVMs) were more prevalent in type 3 FCE (41.2% compared with 11.1% for type 1 FCE, p=0.251, and 0% for type 2 FCE, p=0.043).ConclusionsThe FCE types, stratified by central choroidal thickness, demonstrated distinct morphological characteristics and associated findings. The classification scheme held prognostic implications as type 3 FCE with V shapes were associated with other chorioretinal conditions and were more likely to develop CNVM.