From darkness to light: Reversible bitemporal hemianopia

Pituitary tumors are the third most common primary intracranial neoplasm. Pathologic proliferation of the somatotrophs results as overproduction of growth hormone presenting as acromegaly. In pituitary adenomas typical visual field (VF) defect is bitemporal hemianopsia but tumor size and optic chiasmal position may cause variable VF defects and VF examination may remain normal. We retrospectively reviewed the medical records of 23 acromegalic patients with pituitary adenomas who received VF tests in the Department of Ophthalmology and Endocrinology, Ondokuz Mayis University Hospital, between 2000 and 2012. Pituitary tumor volume was calculated after performing measurements of tumor diameter in three orthogonal planes using Cavalieri's principle. VF test was performed with a Humphrey field analyzer 750 using a 4-mm² Goldmann size III stimulus. The mean age of the 23 patients (11 male/12 female) was 50.4 ± 11.9 years. 15 patients (65.2 %) had normal VF, two patients (9 %) had quadrantanopsia, three patients (13 %) had hemianopsia and three patients (13 %) had three quadrantanopsia. Among the patients with normal VF, four patients had a suprasellar mass that was elevating the chiasm and spreading along the optic tracts. We also observed VF defects typical of a chiasmal compression even though no suprasellar extension was detected in a few cases. Tumor volume of the patients with VF defects was significantly larger than tumor volume of patients with normal VF (p = 0.02). Tumor volume is an important parameter in VF defects. Advanced neuroimaging assesments should always be complemented in patients even with normal VF.

Introduction: Pituitary adenomas are benign tumours that can lead to visual loss through compression of the optic chiasm. Patients with pituitary adenomas often present with visual field defects (commonly bitemporal hemianopia), but some may be asymptomatic. In such cases, abnormalities may only be detected through visual field testing or optical coherence tomography (OCT) of the ganglion cell-inner plexiform layer (GCIPL), which may provide a more sensitive method for detecting such abnormalities. Case Presentation: A 72-year-old man was incidentally found to have binasal OCT-GCIPL thinning during a routine eye examination. Visual acuity was 20/20 in both eyes. Pupils were equal and reactive without a relative afferent pupillary defect. His Humphrey 24-2 SITA-Fast visual field test results were normal. A magnetic resonance imaging (MRI) revealed a nonenhancing (cystic) sellar/suprasellar mass measuring 1.7 cm craniocaudal by 2.1 cm anteroposteriorly, without associated optic chiasm compression. The lesion was suspected to be either a cystic pituitary adenoma or a Rathke’s cleft cyst. Follow-up examination 1 year later showed all findings remained stable, including an unchanged visual acuity, visual fields, OCT-GCIPL, and MRI. Conclusion: The binasal thinning observed on OCT-GCIPL in this case, despite the absence of chiasmal compression on MRI, is suggestive of previous compression of the optic chiasm. This case highlights the potential for spontaneous regression of pituitary adenomas and underscores the importance of OCT-GCIPL as a vital tool for detecting optic chiasmal damage.

BackgroundWe evaluated the accuracy of magnetic resonance imaging (MRI) computed tomography (CT)-like sequences compared to normal-resolution CT (NR-CT) and super-high-resolution CT (SHR-CT) for planning of cochlear implantation.MethodsSix cadaveric temporal bone specimens were used. 3-T MRI scans were performed using radial volumetric interpolated breath-hold (STARVIBE), pointwise-encoding time reduction with radial acquisition (PETRA), and ultrashort time of echo (UTE) sequences. CT scans were performed on two scanners for SHR-CT and NR-CT acquisitions. Two radiologists evaluated accuracy based on preimplantation metrics and the ability to identify various anatomical structures, particularly the facial recess and round window. Wilcoxon rank-sum test and intraclass correlation coefficient (ICC) were used.ResultsThe facial nerve was always clearly visible (score ≥ 2) in the MRI, NR-CT, and SHR-CT scans (p ≥ 0.621). However, the chorda tympani nerve (CTN) was clearly visualized in UTE, STARVIBE, and PETRA sequences in only 33% (2/6 specimens, p = 0.016), 50% (3/6 specimens, p = 0.038), and 83% (5/6 specimens, p = 0.017) of cases, respectively, whereas it was always clearly visualized in SHR and NR-CT (p = 0.426). The round window (RW) was never visualized in MRI sequences (p ≤ 0.010), whereas it was identified in all cases in SHR and NR-CT (p = 1.000). There was a strong correlation between measurements obtained from MRI and CT modalities (ICC ≥ 0.837).ConclusionMRI CT-like sequences assessed the facial nerve in all cases and the CTN in up to 87% of cases. However, the detection of the RW was insufficient for surgical planning. CT and MRI measurements were in agreement.Relevance statementCT-like MRI sequences can image the anatomy of the facial recess and the length of the basal turn of the cochlea with similar accuracy as conventional CT, although they cannot image the round window.Key PointsCT-like MRI sequences are not widely used in preoperative cochlear implantation imaging.CT-like sequences can image the facial recess as well as conventional CT.CT-like sequences can image the basal turn length of the cochlea as well as conventional CT.Round window depiction is not possible with CT-like MRI sequences.Graphical

The Chiasmal Compression Index: An Integrative Assessment Tool for Visual Disturbances in Patients with Pituitary Macroadenomas

In current clinical practice, head and neck (H&N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors' study is to investigate the relevance of using MRI in addition to CT for patient modeling in H&N HTP. CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H&N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRIdb). To quantify the relevance of MRI based segmentation for H&N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (Tmax) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRIdb. In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm). Patient models based on CT (Tmax: 38.0 °C) and CT and MRI (Tmax: 38.1 °C) result in similar simulated temperatures, while CT and MRIdb (Tmax: 38.5 °C) resulted in significantly higher temperatures. The SAR corresponding to these temperatures did not differ significantly. Although MR imaging reduces the interobserver variation in most tissues, it does not affect simulated local tissue temperatures. However, the improved soft-tissue contrast provided by MRI allows generating a detailed brain segmentation, which has a strong impact on the predicted local temperatures and hence may improve simulation guided hyperthermia.

Anecdotally, increasing number of patients are seen at Korle Bu Teaching Hospital (KBTH) with brain tumour. Neuro-ophthalmic symptoms and signs may help in timely diagnosis and intervention. To evaluate the neuro-ophthalmic and clinical characteristics of brain tumour in patients presenting at a tertiary hospital in Ghana. A prospective case series involving 36 consecutive patients newly diagnosed with brain tumour from November 2010 to October 2011, at the Ophthalmology, Neurosurgery and Endocrine units of KBTH, Ghana. All patients had clinical diagnosis of brain tumour with confirmation by computerized tomography (CT) or magnetic resonance imaging (MRI). Thirteen patients had histological confirmation of diagnosis. Presenting Visual acuity, Colour vision, Visual fields and Cranial nerve deficits. Data of 36 patients were analyzed. Ages ranged from 3 to 69 years, mean (SD) 42.56 (±16.6 years). Twenty-six (72%) were females. Tumours included pituitary adenoma (20, 55.5%), meningioma(10, 27.8%), choroid plexus tumour(1, 2.8%), medulloblastoma(1, 2.8%), craniopharyngioma(1, 2.8%), haemangioblastoma(1, 2.8%), thalamic tumour(1, 2.8%) and haemangioma(1, 2.8%). Histologically confirmed tumours included pituitary adenoma (9, 69.2%), meningioma (3, 23.1%), craniopharyngioma (1, 7.7%). One patient had both a pituitary adenoma and meningioma. Blurred vision (30, 83.3%), headache (28, 77.8%) and photophobia (13, 36.1%) were predominant symptoms. Commonest neuro-ophthalmic signs were impaired colour vision (62 eyes, 88.6%), optic atrophy (26, 74.3%), unilateral or bitemporal hemianopia (15, 41.5%) and relative afferent pupillary defect (12, 34.3%). Seven (19.4%) patients were visually impaired and nine (25%) blind. Thirty-three of 72 (45.8%) eyes had monocular blindness. Common neuro-ophthalmic characteristics were blurred vision, headache, impaired colour vision, optic atrophy, and relative afferent pupillary defect (RAPD). Significant numbers of patients were blind or visually impaired at presentation.

Hémianopsie bitemporale révélatrice d’une atteinte toxique sévère à l’éthambutol

The development of computed tomography (CT) and magnetic resonance imaging (MRI) has resulted in the discovery of unsuspected endocrinologically silent pituitary masses (pituitary incidentalomas). The aim of this study was to perform a national survey on pituitary incidentalomas in order to establish an appropriate approach to them. Five hundred and six patients with pituitary incidentalomas were obtained by questionnaire from March 1999 to May 2000 under the auspices of the Ministry of Health, Labor and Welfare in Japan. Two hundred and fifty-eight patients underwent surgery (surgical group), while 248 patients were followed up conservatively for a mean period of 26.9 Months (range 6-173 Months) (non-surgical group). Clinical and biochemical assessment, CT or MRI of the pituitary, and visual field testing by Goldman perimetry were assessed at baseline and 6 Months and Yearly thereafter. Thirty-three patients with pituitary incidentalomas (13.3%) developed tumor enlargement during the mean follow-up period of 45.5 Months. Of 115 estimated non-functioning adenomas, 23 tumors (20.0%) increased during a mean follow-up period of 50.7 Months (range 10-173 Months), while 5 of 94 (5.3%) estimated Rathke's cysts increased in size during follow-up. Pituitary apoplexy occurred in one of 248 patients (0.4%). Pituitary incidentalomas usually follow a benign course. We recommend transsphenoidal adenectomy for a solid mass attached to the optic chiasma estimated to be a pituitary adenoma by MRI. Other patients should be followed up by MRI every 6 Months for the first 2 Years, and then Yearly.

Purpose: To evaluate visual pathway tumor presenting as visual disturbances without extraocular signs and assess the usefulness of various examinations. Methods: Only 35 patients with intracranial tumors (22 males and 13 females) who were initially d iagnosed at our hospital and confirmed by magnetic resonance imaging were enrolled, and previously known intracranial tumor patients and patients with strabismus or proptosis were excluded. Best corrected visual acuity (BCVA), pupillary reflex test, fundus examination, color vision test and visual field test were done to evaluate visual impairments. We investigated the incidence of intracranial tumors and sensitivity of tests. Results: The most common tumors were pituitary tumors (60.0%), followed by meningioma (20.0%) and optic nerve glioma (5.7%). The BCVA ranged from 1.0 to no light perception and the visual acuity of 3 patients was 1.0 in both eyes. Positive relative afferent pupillary defect was seen in 71.4% and abnormal disc findings were found in 58.8% of patients. The color vision test was more specific (sensitivity: 76.6%), and all patients had abnormal visual field defects. Conclusions: Pituitary tumor is the most common intracranial tumor. Among tests, a visual field test is a more sensitive test than other tests for detecting compressive optic neuropathy.

Requests for computed tomography (CT) and magnetic resonance imaging (MRI) scans by doctors with different levels of experience have cost and risk implications globally. Evidence-based appropriateness criteria guide doctors to the suitable use of radiology imaging. There are few studies regarding appropriateness of CT requests in the South African (SA) context. Previous research in the Garden Route district of Western Cape Province, SA, evaluated the appropriateness of scans. To review the appropriateness of CT and MRI scans done in a 6-year follow-up study at one facility. This was a retrospective descriptive study. All CT and MRI scans performed during October 2018 at George Hospital were classified according to American College of Radiology guidelines as: usually appropriate (UA), might be appropriate (MBA), or not appropriate (NA). Stratified analysis allowed simple statistics and some comparison with the previous study. A total of 515 CT and MRI scans were included, of which 81.4% were UA, 7.4% MBA and 11.2% NA. Most scans were requested by medical officers (n=255), followed by consultants (n=126) and junior doctors (n=70). Medical officers made the majority of inappropriate requests. Second-year interns requested the lowest number of inappropriate scans, with registrars not requesting any inappropriate scans. Most of the inappropriate scans were requested after hours. Thirty-seven of the 123 (30.1%) after-hours scans were inappropriately requested compared with 21 of 392 (5.4%) scans during normal working hours, which were inappropriate. Although the majority of scans were being ordered appropriately, pre-authorisation by experienced physicians and incorporation of guidelines would make requests more complete and possibly more appropriate, especially after hours.

Cocaine use is associated with multiple neurovascular complications, including ischemic and hemorrhagic strokes. Intracerebral hemorrhage is especially prevalent in patients with acute cocaine intoxication as defined by positive urine toxin assays.1 In addition, intracerebral hemorrhage in patients with cocaine intoxication are more severe, often associated with intraventricular hemorrhage, and have a poorer prognosis than intracerebral hemorrhage from other causes.2 Still, the majority of patients with cocaine-associated strokes will present with ischemic strokes. Whether intravenous tissue-type plasminogen activator (tPA) can be safely used in patients presenting with ischemic strokes and recent cocaine use is unknown, and their risk toward hemorrhagic conversion is not fully characterized. We describe 2 cases of cocaine-associated ischemic stroke with immediate hemorrhagic transformation after intravenous tPA infusion. A 55-year-old man presented to the emergency department 20 minutes after the sudden onset of left arm weakness while using cocaine. Examination revealed left hemiparesis-hemiataxia and noncontrast head computed tomography (CT) was normal except for bilateral white matter hypointensities suggestive of leukoaraiosis and a nasal septum perforation indicative of chronic intranasal cocaine use (Figure 1). A bolus of intravenous tPA was administered for acute ischemic stroke, with a symptom onset to administration time of 45 minutes. During the intravenous tPA infusion, the systolic blood pressure remained below 170 mm Hg. Immediately after the tPA bolus infusion, a CT-angiogram and postcontrast CT were acquired (Figure 1B). While being transported to the neuro-ICU, the patient complained of new headache and right arm weakness before quickly progressing to coma requiring emergent intubation as tPA infusion completed. Review of initial studies revealed contrast extravasation in the dorsal pons during tPA infusion (Figure 1B, black arrow). A magnetic resonance imaging scan revealed multifocal infarcts and hemorrhages raising suspicion for …

The purpose of this study was to evaluate the use of gadolinium and barium-enhanced magnetic resonance (MR) imaging in detecting intestinal and extraintestinal Crohn's disease and compare MRI with contrast-enhanced helical computed tomography (CT). Twenty-six patients with Crohn's disease underwent imaging examinations, including gadolinium-enhanced, fat suppressed fast multiplanar spoiled gradient-recalled (FMPSPGR) MR imaging with oral 2% barium sulfate and rectal water and with helical CT using i.v. and positive (13) or negative (13) intestinal contrast material. MR images and CT scans were reviewed separately by two radiologists for bowel wall thickness and enhancement, presence of abscess, phlegmon, and fistula. MR images and CT scans were then compared side by side. Surgical, endoscopic, and histopathologic findings and results of barium studies were reviewed to determine the location and severity of involvement of intestinal Crohn's disease. Depiction of mural thickening and/or enhancement was superior on the MR images, which showed 55 (85%) and 52 (80%) of 65 abnormal bowel segments for the two observers, compared with helical CT, which showed 39 (60%) and 42 (65%; P < 0.001, P < 0.05) of bowel segments affected by Crohn's disease. Segments of bowel with moderate or marked mural thickening were depicted equally on MR imaging and helical CT. In mildly diseased segments of bowel, with only slight thickening and enhancement, MR imaging depicted 22 (79%) and 19 (68%) of 28 segments, compared with helical CT, which depicted 9 (32%; P < 0.01), and 13 (46%; P > 0.05) of 28 segments. In the side-by side comparison, MR imaging was preferred over helical CT for depicting normal bowel wall (MR 71%, CT 4%, equal 25%; P < 0.001), mural thickening (MR 41%, CT 11% equal 48%; P < 0.01), mural enhancement (MR 89%, equal 11%; P < 0.001), and overall GI tract evaluation (MR 52%, CT 10%, equal 38%; P < 0.001). Gadolinium-enhanced MR imaging with oral dilute barium sulfate and rectal water depicts intestinal and extraintestinal changes of Crohn's disease and shows promise as a clinically useful tool.

The Imperial Prostate 9 - Approaches To Long-term Active Surveillance: Regular MRI scans versus standard of care (IP9-ATLAS) randomised controlled trial.

Commentary: Rethinking 10-2 visual fields in early diagnosis of glaucoma for a glided glaucoma practice: The right choice to pick up a feeble noise?

The purpose of this study was to examine the relationship between extraprostatic seed placement and seed loss in a cohort of patients who had underwent both computed tomographic (CT) and magnetic resonance (MR) scans at day 0 and day 30 following brachytherapy. Twenty-two patients with 1997 AJC clinical stage T1-T2 prostatic carcinoma were implanted with nonstranded I 125. Patients were selected solely by having a prostate volume between 15 and 60 cc and a willingness to return for 30-day follow-up CT and MR scans. The total number of I-125 sources implanted on day 0 ranged from 50 to 104 (median: 70). Preplan treatment planning methods have been previously described in detail: a modified peripheral loading pattern and treatment margins of 5-10 mm were used. Noncontrast postimplantation CT and MR scans were obtained 1-4 hours after implantation on day 0. The total seed count on days 0 and 30 was verified by plain radiograph. Pelvic MR (T1) images were registered with the CT images in the Varian planning system, using bony landmarks. The number of extracapsular seeds in each quadrant of the circumference was then totaled for each patient. A second set of plain radiographs (for seed counting), as well as CT and MR scans, were obtained 30 days after implantation (day 30) and were similarly analyzed. The number of extraprostatic seeds at day 0 ranged from 13 to 35, making up 17%-48% (median: 34%) of the total number implanted. Of the 22 patients, 10 lost one or more seeds between the implantation day and the 1-month follow-up. The mean number of seeds lost was 1.1 (+/- 1.7). There was no apparent relationship between the percent of extraprostatic seeds and the number of seeds lost. There was no apparent relationship between seed loss and number of seeds less than 3 mm or greater than 3 mm from the prostatic capsule. We have shown here that with CT and MR seed localization, extraprostatic seed placement does not appear to substantially increase the likelihood of seed loss after the procedure.