3D ultrasound-guided resection of low-grade gliomas: principles and clinical examples.

3D ultrasound (US) is a convenient tool for guiding the resection of low-grade gliomas, seemingly without deterioration in patients' quality of life. This article offers an update of the intraoperative workflow and the general principles behind the 3D US acquisition of high-quality images.The authors also provide case examples illustrating the technique in two small mesial temporal lobe lesions and in one insular glioma. Due to the ease of acquiring new images for navigation, the operations can be guided by updated image volumes throughout the entire course of surgery. The high accuracy offered by 3D US systems, based on nearly real-time images, allows for precise and safe resections. This is especially useful when an operation is performed through very narrow transcortical corridors.

[Macular pathology as a cause of visual impairment?]. / Makulapathologie als Ursache einer Visusminderung?

This article reports a case of a pituitary adenoma as the cause of unilateral visual impairment and concomitant unilateral macular pathology. Pituitary adenomas can be classified into hormone-secreting and inactive tumors of the adenohypophysis and lead to typical symptoms in cases of hypersecretion of hormones or hypopituitarism. A pituitary adenoma classically presents with bitemporal hemianopia when compression occurs at the optic chiasm. Imaging is crucial in diagnosing pituitary adenomas. Microsurgical or endoscopic transsphenoidal surgery, hormone therapy and radiotherapy are the treatment options.

A case of IgG4-related hypophysitis without pituitary insufficiency.

CONTEXT: IgG4-related hypophysitis is a novel clinical disease entity, which is typically complicated by hypopituitarism. OBJECTIVE: The objective of the study was to describe a novel case of IgG4-related hypophysitis without pituitary insufficiency and summarize the current relevant literature. PATIENT AND METHODS: A 55-year-old Japanese man presented with an enlarged pituitary gland and bitemporal hemianopsia. Endocrine studies revealed normal pituitary function, although his serum IgG4 level was high. The patient underwent a transsphenoidal biopsy of the pituitary gland, and the pathological tissues were consistent with IgG4-related hypophysitis. Oral prednisolone therapy was started, and after 6 months, his serum IgG4 level decreased and visual field improved. CONCLUSION: We described the first case of IgG4-related hypophysitis without pituitary insufficiency. However, further case collection is needed to characterize the pathophysiology of IgG4-related hypophysitis.

Intraoperative subcortical electrical mapping of optic radiations in awake surgery for glioma involving visual pathways.

OBJECT: Preservation of the visual field in glioma surgery, especially avoidance of hemianopia, is crucial for patients' quality of life, particularly for driving. Recent studies used tractography or cortical occipital stimulation to try to avoid visual deficit. However, optic radiations have not been directly mapped intraoperatively. The authors present, for the first time to their knowledge, a consecutive series of awake surgeries for cerebral glioma with intrasurgical identification and preservation of visual pathways using subcortical electrical mapping. METHODS: Fourteen patients underwent awake resection of a glioma (1 WHO Grade I, 11 WHO Grade II, 2 WHO Grade III) involving the optic radiations. The patients had no presurgical visual field deficit. Intraoperatively, a picture-naming task was used, with presentation of 2 objects situated diagonally on a screen divided into 4 quadrants. An image was presented in the quadrant to be saved and another image was presented in the opposite quadrant. Direct subcortical electrostimulation was repeatedly performed without the patient's knowledge, until optic radiations were identified (transient visual disturbances). All patients underwent an objective visual field assessment 3 months after surgery. RESULTS: All patients experienced visual symptoms during stimulation. These disturbances led the authors to stop the tumor resection at that level. Postoperatively, only 1 patient had a permanent hemianopia, despite an expected quadrantanopia in 12 cases. The mean extent of resection was 93.6% (range 85%-100%). CONCLUSIONS: Online identification of optic radiations by direct subcortical electrostimulation is a reliable and effective method to avoid permanent hemianopia in surgery for gliomas involving visual pathways.

Endoscopic surgery of pituitary tumors.

Endoscopic pituitary surgery has been gaining wide acceptance as the first-line treatment of most functional pituitary adenomas. This technique has many advantages over traditional procedures, and growing evidence supports its use for endocrine control of functioning tumors. This article reviews data on the different modalities of treatment of functioning pituitary adenomas and compares the results. Endoscopic pituitary surgery controls tumor growth and endocrinopathy as well as or better than other treatment modalities. Complication rates are low and patient recovery is fast. Furthermore, surgery provides a means of achieving prompt decompression of neurologic structures and endocrine remission.

The use of diffusion tensor tractography to measure the distance between the anterior tip of the Meyer loop and the temporal pole in a cohort from Southern China.

OBJECT: Anterior temporal lobe resection plus amygdalohippocampectomy can cause damage to the anterior portion of the optic radiation, also known as the Meyer loop, resulting in homonymous superior quadrantanopia. Magnetic resonance diffusion tensor tractography (DTT) of the Meyer loop can help in surgical planning. In this study, the distance of the anterior tip of the Meyer loop to the temporal lobe pole (ML-TP) in the Southern Chinese population was assessed. METHODS: The authors studied 16 Southern Chinese individuals (8 men and 8 women; mean age 45.6 years, range 21-60 years). Diffusion tensor images were obtained with a 3-T MR imaging system using a single-shot spin echo echo planar imaging sequence. Two trained operators, one neurosurgeon (Operator A) and one radiologist (Operator B), carried out the DTT analysis with software iPlan (BrainLAB) and FiberTrak (Philips). RESULTS: For the 32 temporal lobes, the intraclass correlation coefficient (ICC) of the 2 operators' results using iPlan was 0.96, while that of Operator A using iPlan and Operator B using FiberTrak was 0.75. The ICC of Operator B using iPlan and FiberTrak was 0.81. The ML-TP distance of normal lobes (30 lobes [2 lobes that previously underwent surgery were excluded]) was 36.3±5.5 mm (range 26.6-48.9 mm), 36.3±5.3 mm (range 26.8-48.2 mm), and 35.9±6.4 mm (range 20.8-48.4 mm) for Operator A using iPlan, Operator B using iPlan, and Operator B using FiberTrak, respectively (p>0.05). CONCLUSIONS: The 2 operators reached good agreement on ML-TP distance measurement using DTT. The DDT results can be more software dependent than operator dependent. The measurement with FiberTrak demonstrated larger range and standard deviation than measurement with iPlan.

MR tractography predicts visual field defects following temporal lobe resection.

A superior homonymous quadrantanopia is a well recognized complication of anterior temporal lobe resection and occurs because of disruption of the Meyer loop, the anterior part of the optic radiation. The authors used diffusion tensor imaging tractography to visualize the optic radiation before and after surgery, demonstrating the disruption of Meyer loop in a patient who developed a quadrantanopia. Preoperative imaging of the optic radiation will be useful in predicting visual field defects following temporal lobe resection.

Intra-operative mapping of the subcortical visual pathways using direct electrical stimulations.

Despite the risk of postoperative visual field defect following surgery within the temporo-parieto-occipital region, visual mapping has rarely been described, in particular at the subcortical level. In this report, we successfully performed a subcortical mapping of the visual pathways using intra-operative electrical stimulations (IES), during surgery under local anesthesia for a low-grade glioma invading the whole temporal lobe and the temporo-occipital junction. The optic radiations then constituted the posterior and deep functional boundary of the resection, avoiding the occurrence of a post-operative hemianopsia, in spite of an asymptomatic quadrantanopsia. This preliminary experience illustrates the possibility to use intra-operative direct electrical stimulation during surgery of lesions involving the posterior afferent visual system, in order to identify and then preserve the visual pathways, as previously reported for sensorimotor and language subcortical fibers.

[Confrontation test using Bagolini striated glasses--a new screening method for detection of quandrantanopia and hemianopia]. / Konfrontationstest mit Hilfe der Streifengläser nach Bagolini--eine neue Screeningmethode zur Erkennung von Quadrantenausfällen und Hemianopsien.

BACKGROUND: To propose a quick test using striated lens according to Bagolini for detecting quadrantanopic and hemianopic visual field defects. PATIENTS AND METHODS: The results of this test are presented and compared with Goldmann perimetry in five patients suffering from quadrantanopic and hemianopic visual field defects in hypophyseal adenoma (2 x quadrantanopia, 1 x bitemporal hemianopia) and occipital process (2 x homonymous hemianopia). To examine the visual field the patient has to fixate a light at 50 cm distance. Due to the striated glasses two light stripes are generated along the 45 degrees diagonal, crossing in the fixated light in normal binocular vision. The temporal lower and nasal upper quadrants of both eyes and after switch the striated glasses around the horizontal axis, the nasal lower and temporal upper quadrant of both eyes can be tested along the 45 degrees axis. While fixating the lamp the patient is asked (in normal binocularity identical with the crossing point), if one or more of the four light stripes, beginning at the crossing point is shorter or weaker than the others, or interrupted or missing totally. RESULTS: Shortened or absent light stripe indicating quadrantanopic visual field defect agrees with the location of visual field defect in kinetic Goldmann Perimetry. An absent light stripe indicates a complete quadrantanopia, a shortened light stripe an incomplete quadrantanopia. Fixation is warranted easily by the crossing light stripes. CONCLUSION: The dissociation with the aid of striated glasses allows a simultaneous test of both eyes in the 45 degrees-axis of all four quadrants in combination with the location of the visual field defect in this axis. The proposed confrontation test is a simple and quick test without extensive equipment. This test seems to be a useful tool in detecting homonymous or heteronymous quadrantanopic and hemianopic visual field defects for quick screening purposes, especially in immobile patients.

Continuous administration of bromocriptine in the prevention of neurological complications in pregnant women with prolactinomas.

Continuous bromocriptine treatment was given throughout pregnancy to 10 pregnant women with prolactinomas. The dosage of bromocriptine was modified to reduce the serum prolactin level to below 20 ng/ml. Eight patients had continuous bromocriptine treatment started early in their pregnancies, and no tumor-related neurological complications were observed. Continuous bromocriptine treatment was not started at the onset of pregnancy in two patients, and bitemporal hemianopia occurred (at 5 and 7 months of pregnancy). With the start of continuous bromocriptine treatment, a normalization of the visual fields rapidly ensued. The course of the pregnancies and the condition of the newborn infants at birth were normal. The subsequent mental and physical development of the newborn infants (observed up to the age of 6 years) was also normal.