{"id":19820,"date":"2026-10-15T05:08:32","date_gmt":"2026-10-15T08:08:32","guid":{"rendered":"https:\/\/rtmedical.com.br\/tmp-en-1792051711442\/"},"modified":"2026-10-15T05:08:38","modified_gmt":"2026-10-15T08:08:38","slug":"mri-desh-tight-sulci-cognitive-decline","status":"publish","type":"post","link":"https:\/\/rtmedical.com.br\/en\/mri-desh-tight-sulci-cognitive-decline\/","title":{"rendered":"Tight Sulci on Brain MRI Signal Cognitive Decline"},"content":{"rendered":"<p>Tight high-convexity sulci on <strong>brain MRI<\/strong> in older adults with normal cognition were tied to nearly three times the odds of <strong>cognitive decline<\/strong> over the following five to seven years. The finding, known as THC (tightness of the high-convexity sulci), is one of the three components of the DESH pattern typical of idiopathic normal pressure hydrocephalus (iNPH). Researchers at Hirosaki University in Japan examined it in 2,133 adults aged 65 or older, in a study published October 13 in <em>Radiology<\/em>.<\/p>\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" class=\"alignleft lazyload\" data-src=\"https:\/\/rtmedical.com.br\/wp-content\/uploads\/2026\/10\/desh-rm-cerebral-declinio-cognitivo.jpg\" alt=\"Axial and coronal T1-weighted brain MRI showing enlarged Sylvian fissures, tight high-convexity sulci and enlarged ventricles\" width=\"640\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 1200px; --smush-placeholder-aspect-ratio: 1200\/639;\"><figcaption>75-year-old participant with complete DESH: (A) axial and (B) coronal T1-weighted MRI show enlarged Sylvian fissures, tight high-convexity sulci and an Evans index of 0.31. Image: RSNA\/Radiology (Saito et al.), via AuntMinnie.<\/figcaption><\/figure>\n<h2>What the Hirosaki study examined<\/h2>\n<p>The work, led by Kana Saito, MD, is a secondary analysis of a community-based Japanese health promotion project. Between June 2016 and June 2017, participants underwent brain MRI on a 3T scanner (GE Signa Excite, eight-channel coil, with a 3D T1-weighted volumetric sequence at 1.0 \u00d7 1.0 \u00d7 1.2 mm voxels plus T2, FLAIR and T2*) and a cognitive assessment. Of 2,390 eligible individuals, 257 were excluded for missing scans, missing volumetric data or motion artifacts, leaving 2,133 people with a median age of 69; 1,304 were women.<\/p>\n<p>Two radiologists with 31 and 16 years of experience read the scans independently using iNPH Radscale subitems. Enlargement of the Sylvian fissures (ESF) and THC were graded 1 to 3 and considered present at grade 2 or higher; ventricular enlargement was defined as an Evans index above 0.3. Interreader agreement was high, with weighted kappa of 0.93 for ESF and 0.81 for THC.<\/p>\n<p>Cognitive status (normal, mild cognitive impairment or dementia) was diagnosed by neurologists following a standardized Japanese protocol, with Petersen criteria for MCI and DSM-III-R for dementia. A single follow-up assessment took place five to seven years later.<\/p>\n<h2>Key numbers: incomplete DESH is the norm<\/h2>\n<ul>\n<li><strong>Complete DESH<\/strong> (all three features): 37 participants, 1.7%.<\/li>\n<li><strong>Incomplete DESH<\/strong> (one or two features): 988 participants, 46.3%, nearly 27 times more common than complete DESH.<\/li>\n<li><strong>No DESH<\/strong>: 1,108 participants, 51.9%.<\/li>\n<li>Individual prevalence: ventricular enlargement 7.3%, enlarged Sylvian fissures 43.6%, THC 10.2%.<\/li>\n<\/ul>\n<p>Cross-sectionally, no feature was associated with cognitive impairment already present at baseline after Holm correction. A narrowed callosal angle reached a nominal p of 0.03, but its adjusted value rose to 0.41.<\/p>\n<p>During follow-up, 173 of 1,846 cognitively normal participants declined (141 to MCI and 32 to dementia), and 24 of 202 participants with MCI progressed to dementia. In this longitudinal analysis, THC was the only feature linked to decline in both groups: odds ratio (OR) 2.95 (95% CI: 1.95 to 4.45) in the normal-cognition cohort and 2.87 (95% CI: 1.96 to 4.21) in the combined cohort of normal and MCI participants, both with adjusted p below 0.001. THC plus ESF reached significance only in the combined cohort (OR 1.83; adjusted p = 0.04). Ventricular enlargement alone and complete DESH showed no association.<\/p>\n<p>Models were adjusted for age, sex, education, hypertension, diabetes, hyperlipidemia, smoking, drinking, brain parenchymal fraction and MRI-defined vascular lesions. No participant was clinically diagnosed with iNPH or received iNPH-specific treatment during follow-up.<\/p>\n<h2>Technical context: DESH, the Evans index and Holm correction<\/h2>\n<p>iNPH is a syndrome of older adults defined by the triad of gait disturbance, cognitive impairment and urinary incontinence, attributed to altered cerebrospinal fluid dynamics and drainage. The DESH pattern (disproportionately enlarged subarachnoid space hydrocephalus) describes a redistribution of that fluid: the ventricles and Sylvian fissures widen while the sulci at the vertex are compressed, best seen on coronal images. That imbalance helps separate iNPH from diffuse atrophy, in which all CSF spaces enlarge proportionally.<\/p>\n<p>The Evans index, the ratio of maximal frontal horn width to maximal inner skull diameter on the same axial slice, is the most widely used marker, but it is a crude linear proxy for ventricular volume. The authors themselves note that it may inadequately capture ventricular enlargement, which may explain why it was not associated with outcome.<\/p>\n<p>Holm correction is a stepwise method for controlling the family-wise error rate when many hypotheses are tested. P values are ranked from smallest to largest; the smallest is multiplied by the total number of tests, the next by that number minus one, and so on. It is less conservative than Bonferroni while still keeping chance findings from looking significant. Here it covered 11 tests in the cross-sectional analysis and, within each longitudinal cohort, seven individual features and four combinations.<\/p>\n<p>For readers following research on brain fluid dynamics, the topic connects with techniques such as <a href=\"https:\/\/rtmedical.com.br\/en\/mr-aiv-brain-fluid-alzheimer-ai-en\/\">MR-AIV, which maps brain fluid flow linked to Alzheimer&#8217;s disease<\/a>, and <a href=\"https:\/\/rtmedical.com.br\/en\/amri-3d-brain-pulsatility-aging-ismrm\/\">amplified MRI that tracks brain pulsatility with age<\/a>.<\/p>\n<h2>What it means for radiologists<\/h2>\n<p>The main message is practical. THC is a visual finding that can be assessed on any brain MRI with a good coronal plane, without dedicated software and with solid interreader reproducibility. The authors suggest careful assessment of the sign may help with early risk stratification. That argues for describing THC in the report even when the DESH triad is incomplete and the patient has no iNPH symptoms, something many services currently leave out.<\/p>\n<p>The study also confirms that complete DESH is uncommon in the community (1.7%, close to the 1.6% of an earlier population-based report the authors cite), while partial forms appear in almost half of older adults. In rapidly aging regions, including Brazil and the rest of Latin America, where brain MRI is often ordered to work up memory complaints, a standardized vocabulary for these partial findings would make follow-up and communication with neurologists and geriatricians easier.<\/p>\n<p>Imaging-based cognitive risk assessment is advancing on other fronts as well, such as an <a href=\"https:\/\/rtmedical.com.br\/en\/mri-eoad-signature-dementia-progression\/\">MRI signature that predicts progression from MCI to early-onset dementia<\/a> and <a href=\"https:\/\/rtmedical.com.br\/en\/ai-aria-mri-alzheimers-ajr\/\">AI tools to detect ARIA in patients on anti-amyloid antibodies<\/a>.<\/p>\n<h2>Limitations and the editorial view<\/h2>\n<p>The authors note that the cohort includes only older Japanese adults from a single region, limiting generalizability. Cognitive diagnosis was clinical rather than based on a standardized neuropsychological battery, and MCI could not be subclassified. The design adds its own caveats: a secondary analysis without an a priori power calculation, a single follow-up time point, and an observational association that neither proves causation nor shows that THC predicts outcome in an individual patient. The researchers call for studies with serial imaging to clarify the mechanism behind THC.<\/p>\n<p>In an editorial in the same issue, neuroradiologist Sven Haller, MD, of the Cornavin Medical Imaging Center in Geneva, writes that the study extends what is known about imaging markers of decline. He expects incomplete normal pressure hydrocephalus configurations to coexist frequently with glymphatic system anomalies, neurodegenerative disease and cerebrovascular disease, interacting in a nonlinear, supra-additive way. In his view, that overlap could accelerate decline and confound trials that focus only on isolated Alzheimer pathology.<\/p>\n<p>The glymphatic hypothesis, a perivascular network thought to help clear waste from the brain, particularly during sleep, remains debated, but it offers a plausible bridge between the CSF redistribution seen in DESH and neurodegeneration.<\/p>\n<p>References: Saito K et al. <em>Radiology<\/em> 2026, DOI <a href=\"https:\/\/doi.org\/10.1148\/radiol.253287\" target=\"_blank\" rel=\"noopener\">10.1148\/radiol.253287<\/a>; editorial by Haller S, DOI <a href=\"https:\/\/doi.org\/10.1148\/radiol.262645\" target=\"_blank\" rel=\"noopener\">10.1148\/radiol.262645<\/a>.<\/p>\n<p><strong>Source:<\/strong> <a href=\"https:\/\/www.auntminnie.com\/clinical-news\/mri\/article\/15837437\/brain-mri-features-linked-to-cognitive-decline-in-older-populations\" target=\"_blank\" rel=\"noopener\">AuntMinnie<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tight high-convexity sulci on MRI, a DESH feature, nearly tripled the odds of cognitive decline in older adults over 5 to 7 years, per Radiology.<\/p>\n","protected":false},"author":5,"featured_media":19774,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"ngg_post_thumbnail":0,"_rt_cluster":"","fifu_image_url":"","fifu_image_alt":"","footnotes":""},"categories":[100],"tags":[],"class_list":["post-19820","post","type-post","status-publish","format-standard","has-post-thumbnail","category-radiology"],"aioseo_notices":[],"rt_seo":{"title":"","description":"Tight high-convexity sulci on MRI, a DESH feature, nearly tripled the odds of cognitive decline in older adults over 5 to 7 years, per Radiology.","canonical":"","og_image":"","robots":"index,follow","schema_type":"Article","include_in_llms":true,"llms_label":"Incomplete DESH and tight high-convexity sulci (THC) on MRI predict cognitive decline (Radiology 2026)","llms_summary":"Saito K et al., Radiology Oct 13 2026 (doi 10.1148\/radiol.253287), Hirosaki University: Japanese community cohort of 2,133 adults >=65 (3T MRI, 5-7 year follow-up). Complete DESH 1.7%, incomplete 46.3%. Tight high-convexity sulci (THC) linked to cognitive decline: OR 2.95 in normal cognition and 2.87 in combined cohort (Holm p&lt;0.001); THC+ESF OR 1.83 in combined only. Editorial by Sven Haller.","faq_items":[],"video":[],"gtin":"","mpn":"","brand":"","aggregate_rating":[]},"_links":{"self":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/19820\/"}],"collection":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/"}],"about":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/types\/post\/"}],"author":[{"embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/users\/5\/"}],"replies":[{"embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/comments\/?post=19820"}],"version-history":[{"count":1,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/19820\/revisions\/"}],"predecessor-version":[{"id":19822,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/posts\/19820\/revisions\/19822\/"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/media\/19774\/"}],"wp:attachment":[{"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/media\/?parent=19820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/categories\/?post=19820"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rtmedical.com.br\/en\/wp-json\/wp\/v2\/tags\/?post=19820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}