Microvascular anatomy of the medial temporal region

OBJECTIVE The authors investigated the microvascular anatomy of the hippocampus and its implications for medial temporal tumor surgery. They aimed to reveal the anatomical variability of the arterial supply and venous drainage of the hippocampus, emphasizing its clinical implications for the removal of associated tumors. METHODS Forty-seven silicon-injected cerebral hemispheres were examined using microscopy. The origin, course, irrigation territory, spatial relationships, and anastomosis of the hippocampal arteries and veins were investigated. Illustrative cases of hippocampectomy for medial temporal tumor surgery are also provided. RESULTS The hippocampal arteries can be divided into 3 segments, the anterior (AHA), middle (MHA), and posterior (PHA) hippocampal artery complexes, which correspond to irrigation of the hippocampal head, body, and tail, respectively. The uncal hippocampal and anterior hippocampal-parahippocampal arteries contribute to the AHA complex, the posterior hippocampal-parahippocampal arteries serve as the MHA complex, and the PHA and splenial artery compose the PHA complex. Rich anastomoses between hippocampal arteries were observed, and in 11 (23%) hemispheres, anastomoses between each segment formed a complete vascular arcade at the hippocampal sulcus. Three veins were involved in hippocampal drainage—the anterior hippocampal, anterior longitudinal hippocampal, and posterior longitudinal hippocampal veins—which drain the hippocampal head, body, and tail, respectively, into the basal and internal cerebral veins. CONCLUSIONS An understanding of the vascular variability and network of the hippocampus is essential for medial temporal tumor surgery via anterior temporal lobectomy with amygdalohippocampectomy and transsylvian selective amygdalohippocampectomy. Stereotactic procedures in this region should also consider the anatomy of the vascular arcade at the hippocampal sulcus.

The contribution of the proximity of the retinal detachment to the fovea for postoperative metamorphopsia after 27-gauge pars plana vitrectomy for the primary rhegmatogenous retinal detachment

Purpose To investigate clinical factors contributing to metamorphopsia after 27-gauge pars plana vitrectomy (27GPPV) for primary rhegmatogenous retinal detachment (RRD) to reveal whether the proximity of the preoperative retinal detachment to the fovea is associated with postoperative metamorphopsia. Methods We retrospectively reviewed medical records of 77 eyes of 77 patients after 27GPPV for RRD. Patients were subdivided into three groups using optical coherence tomography findings: Group A, patients with RRD outside the vascular arcade; Group B, patients whose condition was present within the vascular arcade, but without foveal detachment; and Group C, patients with foveal detachment. Results The average metamorphopsia score (°) assessed with M-charts 12 months after surgery was 0.01 ± 0.04 in Group A (24 eyes), 0.08 ± 0.18 in Group B (20 eyes), and 0.49 ± 0.48 in Group C (33 eyes) (p<0.001). Logistic regression analysis revealed that metamorphopsia at 12 months after surgery significantly correlated with the proximity of the retinal detachment to the fovea (p = 0.007). Conclusion Metamorphopsia after 27GPPV for RRD correlated with the proximity of the preoperative retinal detachment to the fovea. Attention should be paid to the possibility of postoperative metamorphopsia development when retinal detachment is present within a vascular arcade even if the fovea is not involved.

Comparison of Retinal Vascular Arcade Trajectory Between Eyes with an Idiopathic Macular Hole and the Healthy Fellow Eye

Purpose: We aimed to present a method to evaluate the retinal arcade vascular trajectory by measuring the distance between the retinal veins in eyes with idiopathic macular hole (IMH) and compare this measurement with healthy fellow eyes.Methods: In this Cross-sectional study18 patients with unilateral IMH were enrolled. We used standard fundus photographs, which were obtained from each eye with a digital fundus camera using a 55-degree lens. The calculation of the retinal arcade vascular trajectories was done by drawing and measuring 5 vertical lines within the macular area. Results: The mean age of the patients was 65±9 years. The between-groups differences of each vertical line were not statistically significant, except for the differences between the most temporal line, which was greater in the diseased group (9388 vs. 8322 mm; P=0.034). The ratio between the 5th (most temporal) and the third (fovea-center) vertical lines was greater than 1 (V-shape) in 72% of eyes with a macular hole, whereas it was less than one (U-shape) in 78% of control eyes (P=0.003). Conclusions: We demonstrated that in eyes with an IMH the vascular arcade has more tendency to diverge on its path temporal to the fovea.

Factors associated with axial length elongation in high myopia in adults

AIM: To investigate the association of axial length (AL) and ocular factors on AL elongation. METHODS: A retrospective chart review of patients who underwent two or more AL examinations for more than two years. Totally 4 groups were divided according to initial AL (<24 mm, 24-26 mm, 26-28 mm, ≥28 mm). Initial fundus photograph was used to find risk factors associated AL elongation. RESULTS: The mean age of the patients was 47.21±7.79y. AL remained almost unchanged in the groups with AL<24 mm and 24≤AL<26 mm. On the contrary, AL increased by 0.011 mm/y in the group with 26≤AL<28 mm and 0.035 mm/y in the group with AL≥28 mm (P<0.001). In high myopia, AL elongation increased in eye with longer AL (r=0.003, P=0.024), female gender (r=0.014, P=0.019), eye with larger peripapillary chorioretinal atrophic area (r=0.002, P=0.019), and smaller vascular arcade angle (r=-0.004, P=0.006). The risk of elongation 0.03 mm/y in high myopia was increased in female gender (P=0.040), and gradually increased in eye with large peripapillary chorioretinal atrophy area (P<0.01). CONCLUSION: AL elongate significantly in the eye with longer AL, female gender, and the eye with larger atrophic area and smaller arcade angle on fundus photography.

Use of Polyamide (Nylon) Cable Ties for Vascular Ligation of Healthy Equine Jejunal Mesentery

Jejunal vascular ligation is an essential step in performing jejunojejunostomy. Hand sewn ligation is typically used and can increase operative time with long sections of bowel to be removed. Nylon cable ties (NCT) have been used for vascular ligation in horses but are yet to be investigated for application on the mesenteric vasculature of the gastrointestinal tract. Our objective was to evaluate the efficacy and short-term safety of NCT jejunal mesenteric vessel ligation in healthy horses. Eight healthy adult horses underwent midline celiotomy. A segment of jejunal mesentery was identified (≥4 arcades). Briefly, three fenestrations (proximal, middle, distal) were made 5–10 mm apart adjacent to the first and last vascular arcade to be ligated. Two sterilized NCT were passed to encircle the mesentery through the proximal and middle fenestrations, separated by intact mesentery. NCT were closed tightly and the vascular pedicle transected with Mayo scissors through the distal fenestration. Jejunojejunostomy was then performed and the mesentery sutured closed. The number of vascular arcades and time to ligate using NCT were recorded. At 2 weeks, horses underwent repeat celiotomy to assess the healing of the NCT ligation site and an equal number of vascular arcades were hand sewn double ligated using 2-0 Polyglactin 910 as a timed comparison. NCT mesenteric ligation was significantly faster than hand sewn methods (P &lt; 0.01). Effective hemostasis was achieved in all cases. There was no evidence of local infection or adhesions at 14 days post-operatively. Further investigation in the long-term effects in horses as well as horses with strangulating jejunal lesions are needed for clinical application.

Invasive Klebsiella syndrome with coexisting fungal endophthalmitis

Endogenous endophthalmitis accounts for approximately 5 – 10% of all endophthalmitis cases. We report a case of a middle-aged gentleman with underlying uncontrolled diabetes mellitus who presented with fever and generalised body weakness for one week. He was diagnosed with invasive Klebsiella syndrome based on blood culture with presence of bilateral pleural effusion, liver abscess, renal impairment and sphenoidal sinusitis. The patient developed sudden bilateral painless reduced vision on day two of admission. Ocular examination revealed bilateral severe anterior chamber reaction and severe vitritis that obscured the view of the fundus. Ocular B-scan ultrasonography showed multiple loculations in the posterior segment in both eyes. There was soft tissue density with calcification in the left sphenoid sinus on computed tomography of the orbit. He was treated for bilateral endogenous endophthalmitis with multiple intravitreal antibiotic injections, but showed no improvement. Functional endoscopic sinus surgery was performed and revealed that the left sphenoid sinus was filled with fungal balls. Following drainage of sphenoidal pus, there was resolution of vitritis and fundus examination showed features of underlying fungal infection with a “string of pearls” present along the vascular arcade of both eyes. The patient was diagnosed with bilateral endogenous endophthalmitis secondary to invasive Klebsiella syndrome with coexisting fungal endophthalmitis secondary to sphenoid mycetoma. In addition to repeated intravitreal antibiotic injections, he was also treated with systemic and topical antifungal therapy. At three months post treatment, the infection resolved and his vision improved from counting fingers to 6/36 bilaterally.

Presumed Retinal Metastasis from Lung Adenocarcinoma: A Case Report and Literature Review

A 63-year-old Caucasian man with metastatic lung adenocarcinoma undergoing chemotherapy and external radiotherapy was referred for routine eye examination. Although he was asymptomatic, ocular examination revealed a relatively well-circumscribed whitish retinal lesion measuring 0.5 × 0.5 × 0.5 mm located along the inferotemporal vascular arcade in the right eye. Optical coherence tomography (OCT) showed a hyperreflective dome-shaped lesion occupying the inner retinal layers with few hyperreflective dots overlying the retina in the posterior vitreous consistent with tumor cells. Fluorescein angiography revealed early hyperfluorescence and late staining without leakage at the lesion site. A diagnosis of presumed retinal metastasis from lung adenocarcinoma was made. At 2 months follow-up after completion of chemotherapy, the retinal lesion was found to have regressed completely leaving minor irregularities in the inner retinal layers on OCT. To date, there have been only 41 cases of carcinoma metastasis to the retina reported in the literature including the current case. Despite its rarity, retinal metastasis should be considered in the differential diagnosis of a white-yellow retinal mass with/without overlying vitreous cells especially in patients with a history of systemic cancer.

Idiopathic Dural Optic Nerve Sheath Calcification Associated with Sclerochoroidal Calcification: Case Report and Review of Literatures

We present a patient with idiopathic intracranial calcifications with simultaneous involvement of sclera, choroid, optic nerve, and trochlear apparatus. A 70-year-old woman with bilateral decreased vision was referred to our hospital. Ocular examinations revealed sclerochoroidal mass beneath superotemporal vascular arcade in macular area. Orbital CT scan shows bilateral calcification of dural optic nerve sheath and posterior wall of the globe as well as calcification in the trochlear apparatus and brain. Ultrasound showed highly reflective echogenic lesion with shadowing. OCT revealed rolling topography with thinning of the overlying choroid and outer nuclear layer as well as absence of the external limiting membrane and inner segment-outer segment junction. Slight irregular thickening of the retinal pigment epithelium is present. It is the first case of simultaneous bilateral dural optic nerve sheath and sclerochoroidal calcification.

Fundus autofluorescence in premature infants

To describe fundus autofluorescence (FAF) patterns in premature infants and to determine whether FAF increases gradually with increasing post-gestational age. This was a cross-sectional, observational and descriptive case series. FAF images were obtained from patients screened for Retinopathy of Prematurity. The presence of the following hypo-autofluorescence areas/structures was graded and ranked: macular pigment (foveal centre), optic nerve head, peripapillary vessels/vascular arcade (PP/VA), and equatorial vessels (EqV). Ranks were attributed to the number of structures visualized from the posterior pole towards the periphery. The rank of FAF could then be analysed by Spearman’s correlation against age. Additionally, patients were divided by age into group 1 (< 40 weeks of corrected gestational age (WCGA)) and group 2 (> 40 WCGA). Differences between groups were tested with the Mann–Whitney U test. Thirteen patients were analysed. The mean WCGA at examination was 47.85 weeks. Spearman’s correlation showed a strong positive correlation (r = 0.714) (P = 0.006) of FAF and WCGA. The Mann–Whitney U test revealed that the PP/VA and EqV were significantly more visible at > 40 WCGA than at < 40 WCGA (8.0 [P = 0.016] and 7.5 [P = 0.03], respectively). Patterns of FAF are described for the first time in premature infants. FAF increases gradually with age and centrifugally from the posterior pole towards the equator in premature infants.

Clinical Features and Treatment of Inactive Proliferative Diabetic Retinopathy

Background To investigate the clinical features and results after vitrectomy for inactive proliferative diabetic retinopathy (IPDR).Methods Retrospective review of 40 eyes of 21 IPDR patients who underwent 23G or 25G minimally invasive vitrectomy between January 2018 and December 2019 in Tianjin Medical University Eye Hospital.The average follow-up period was 8.7 months. Outcome measures were best-corrected visual acuity (BCVA), clinical features and intraoperative findings of IPDR.Results All eyes were performed with panretinal photocoagulation (PRP) for average 1.6 years before operation. Fundus examination showed the optic disc was pale, and a mass of yellowish-white fibroproliferative membrane was around the optic disc and vascular arcade. Thirty-three eyes (82.5%) were accompanied by tractional retinal detachment, and macula was involved in 9 eyes (22.5%). The vitreous adhered with the retina tightly. The mid-peripheral retina was thin. Thirty-one eyes (77.5%) were accompanied by small branch retinal artery and vein occlusion. Fourteen eyes (35.0%) occurred iatrogenic retinal break during vitrectomy. The median LogMAR of BCVA significantly improved from 1.0 (20/200)preoperatively to 0.92 (20/167) postoperatively (P = 0.000).Conclusions The fundus manifestation of IPDR was quiet and special. Vitrectomy could improve patients’ visual acuity, but the incidence of iatrogenic retinal break was high.Vitrectomy could be performed by well-skilled vitro-retinal surgeons according to the minimum quantitative principle.